KR20030042616A - Light guided panel and manufacturing method thereof - Google Patents

Abstract

A light guide plate and a manufacturing method thereof are disclosed. The light guide plate according to an embodiment of the present invention is formed on the rear surface of the light guide plate and the light guide plate is installed at at least one end of the light guide plate, the curved light reflecting structure consisting of a predetermined portion of a semi-circle or semi-circle open to the light source The light guide plate according to another embodiment of the present invention includes: a curve formed on a rear surface of a light guide plate and a light guide plate having a light source installed at at least one end thereof, and formed of a predetermined portion of a semi-ellipse or a semi-ellipse open with respect to the light source. And light reflecting structures of the type. According to the present invention, it is possible to provide a light guide plate having improved light brightness and light uniformity by simply forming light reflection structures having curved irregularities, thereby making a great contribution to the surface light source device industry.

Description

Light guide plate and manufacturing method thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light guide plate and a manufacturing method thereof, and to a light guide plate used in a planar light source device and a manufacturing method thereof.

The light guide plate is increasing its utilization in each field, including liquid crystal display, advertising display panel, lighting.

FIG. 1A is a schematic view for explaining a planar light source device employing a light guide plate, and FIG. 1B is a schematic view showing a shape of a light reflection structure formed in a conventional light guide plate.

Referring to FIG. 1A, the planar light source device includes a light guide plate 20 including a light source 10 for emitting light, a light guide plate for converting linear light into a planar shape, and a light reflection structure for reflecting induced light; A diffusion sheet 30 for uniformly diffusing light diffused by the light reflection structure, a prism sheet 40 for converting a propagation path of the light emitted from the diffusion sheet 30, and a protective sheet for protecting the prism sheet 40. 50 and a reflective sheet 60 that reflects light under the light guide plate 20. At this time, the light source 10 is generally made of a fluorescent lamp or the like and is installed at at least one end of the light guide plate 20. As the light guide plate, an acrylic resin plate is mainly used.

Referring to FIG. 1B, the light reflection structure 22 is formed in a dot shape on the back surface of the acrylic resin plate 21.

As a method of forming the dot-shaped light reflection structure 22, a method of printing a dot-shaped light reflection material on the surface of the acrylic resin plate 21 using a printing screen printing machine and a light reflection structure (on the back surface of the light guide plate) There is a method of injecting the acrylic resin plate 21 by designing 22 to be integrally formed.

Although the formation of dots by printing is more productive than in the case of the injection method, light absorption phenomenon occurs in the printing ink in the light reflection structure 22 and a space is generated between the dots, resulting in a very low light utilization rate. There is a problem that the luminance and light uniformity is lowered due to the change in properties depending on time and environmental variables.

Formation of dots by injection is characterized by higher light utilization efficiency than the case of printing because light absorption does not occur in the light reflection structure 22, but a mold for manufacturing grooves for the light reflection structure 22 in the light guide plate itself Since this is necessary, there is a problem that the cost is high and the time required for manufacturing the mold compared to the printing method.

On the other hand, the above two methods have a common problem that takes a long time when modifying the pattern.

The technical problem to be achieved by the present invention is to provide a light guide plate and a method of manufacturing the same, which can achieve a uniform distribution of light on the entire back surface, and can improve productivity at a low cost.

1A is a schematic diagram for explaining a planar light source device employing a light guide plate;

1B is a schematic view showing the shape of a light reflection structure formed in a conventional light guide plate;

2A to 2D are schematic views for explaining a light guide plate according to Embodiment 1 of the present invention;

3A to 3C are schematic views for explaining a light guide plate according to Embodiment 2 of the present invention;

4A and 4B are schematic views for explaining a light guide plate according to Embodiment 3 of the present invention;

5A and 5B are schematic views for explaining a light guide plate according to Embodiment 4 of the present invention;

6A and 6B are schematic views for explaining a light guide plate according to Embodiment 5 of the present invention;

7A and 7B are schematic views for explaining a light guide plate according to Embodiment 6 of the present invention;

8A and 8B are schematic views for explaining a light guide plate according to Embodiment 7 of the present invention; And

9 is a schematic diagram illustrating a light guide plate according to Embodiment 8 of the present invention.

According to one aspect of the present invention, there is provided a light guide plate including: a light guide plate having a light source installed at at least one end thereof; It is formed on the rear surface of the light guide plate, characterized in that it comprises a semi-circle open to the light source or a curved light reflecting structure consisting of a predetermined portion of the semi-circle.

At this time, the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire rear surface of the light guide plate and have a radius of a length not smaller than a distance from the one end to which the light source is installed to the other end opposite to the one end, the predetermined radius of the semicircle or the semicircle. The light reflecting structure selected from the light reflecting structures intersects with the plurality of light reflecting structures, and the distance between the light reflecting structures and the light reflecting structures is increased so that the number of intersection points due to the crossing increases.

In addition, the light source is installed at one end and the other end of the optical guide plate facing each other; The rear surface of the light guide plate may include: a first light reflection portion where the light reflection structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflection portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflecting structures may comprise: a semicircle or a predetermined portion of the semicircle having a radius of a length not smaller than a distance from the one end or the other end to which the light source is installed, to the center portion, and from the light reflecting structures Any one of the selected light reflecting structures intersects with the plurality of light reflecting structures, and as the distance from the light source increases, the number of crossing points due to the crossing increases.

Here, fine light reflection structures may be further formed on the rear surface thereof.

Furthermore, the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire back surface of the light guide plate, and are composed of semicircles of the same origin having different radii or predetermined portions of the semicircles, wherein the semicircles located at the outermost sides of the semicircles are the one end. The radius of the length not smaller than the distance from the other end to the one end opposite to the other end, and any one of the light reflection structure selected from the light reflection structures intersect with a plurality of the light reflection structures to form intersection points.

In addition, the light source is installed at one end and the other end of the optical guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflecting structures may be composed of semicircles of the same origin having different radii or predetermined portions of the semicircles, wherein the semicircle located at the outermost part of the semicircles is the distance from the one end or the other end to the center portion. A length not smaller than a radius is used, and one light reflection structure selected from the light reflection structures intersects with the plurality of light reflection structures to form intersection points.

According to another aspect of the present invention, there is provided a light guide plate including a light guide plate having a light source installed at at least one end thereof; It is formed on the back of the light guide plate, characterized in that it comprises a curved light reflecting structure consisting of a semi-ellipse or a predetermined portion of the semi-ellipse open with respect to the light source.

At this time, the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire rear surface of the light guide plate, the length of which is not smaller than the distance from the one end to which the light source is installed to the other end opposite to the one end is half the length of the short axis and has a constant long axis length. The semi-ellipse having a portion or a predetermined portion of the semi-ellipse, and any one of the light reflecting structure selected from the light reflecting structure intersects the plurality of light reflecting structures, the farther away from the light source It is formed so that the number of intersection points by intersection increases.

In addition, the light source is provided at one end and the other end of the light guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the central portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflection structures may include a half ellipse having a predetermined long axis length or a predetermined portion of the semi ellipse having a length not smaller than a distance from the one end or the other end to which the light source is installed to the center. The light reflecting structure selected from the light reflecting structures intersects with the plurality of light reflecting structures, and as the distance from the light source increases, the number of intersection points due to the crossing increases.

Here, fine light reflection structures are further formed on the rear surface thereof.

Furthermore, the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire back surface of the light guide plate, and are composed of semi-ellips or predetermined portions of the semi-ellips having different lengths and constant sizes of short axis and long axis at the same origin. The semi-ellipse positioned at the outermost side has a length that is not smaller than the distance from the one end to the other end facing the one end, and the half length of the short axis length, and any one light reflection structure selected from the light reflection structures Intersections are formed by crossing the light reflection structures.

In addition, the light source is installed at one end and the other end of the optical guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflecting structures may include: semi-ellips having a constant ratio of short axis and long axis at the same origin and having different sizes, or predetermined portions of the semi-ellips, wherein the semi-ellipse positioned at the outermost of the semi-ellipses is the one side. A length that is not smaller than the distance from the end to the other end is shortened, and any light reflection structure selected from the light reflection structures intersects with the plurality of light reflection structures to form intersection points.

According to an aspect of the present invention, there is provided a method of manufacturing a light guide plate, including: providing a light guide plate on which a light source is installed at at least one end thereof; At least one rotator having a sanding pad provided with abrasive particles on the rear surface of the optical induction plate, the rotational movement and the progressing operation that proceeds in parallel with the light source are repeatedly performed at a constant speed to form a semicircle or a predetermined portion of the semicircle. Forming curved light reflecting structures.

At this time, the light source is installed on only one end of the light guide plate; The sanding pad of the rotor has a donut-shaped shape whose length is not smaller than a distance from the one end to the other end facing the one end.

In addition, the light source is installed on only one end of the light guide plate; The sanding pad of the rotator has a radius of a length not smaller than a distance from the one end to the other end facing the one end.

In addition, the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator has a radius of a length not smaller than the distance from the one end to the center of the rear surface.

Furthermore, the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator has a donut shape having a radius of the outer circumference of a length not smaller than the distance from the one end to the center of the rear surface.

In addition, the light source is installed on one side end and the other end of the light guide plate facing each other; The rotor is provided with two, and the sanding pad of each of the rotors is positioned symmetrically about the center of the back to operate the rotors simultaneously.

Furthermore, the method may further include forming a fine light reflection structure on the back surface of the light guide plate using a blaster or a sander.

According to another aspect of the present invention, there is provided a method of manufacturing a light guide plate including: providing a light guide plate on which a light source is installed at at least one end thereof; At least one rotator provided with sanding pads provided with abrasive particles on the rear surface of the light guide plate, and simultaneously performs a rotation operation and a traveling operation that proceeds in parallel with the light source at a constant speed, and thus a half ellipse or a predetermined portion of the semi ellipse. Characterized in that it comprises the step of forming a curved light reflecting structure consisting of.

At this time, the light source is installed on only one end of the light guide plate; The sanding pad of the rotor has a donut-shaped shape whose length is not smaller than a distance from the one end to the other end facing the one end.

In addition, the light source is installed on only one end of the light guide plate; The sanding pad of the rotator has a radius of a length not smaller than a distance from the one end to the other end facing the one end.

In addition, the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator has a radius of a length not smaller than the distance from the one end to the center of the rear surface.

Furthermore, the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator has a donut shape whose length is not smaller than the distance from the one end to the center of the rear surface.

In addition, the light source is installed on one side end and the other end of the light guide plate facing each other; The rotor is provided with two, and the sanding pad of each of the rotors is positioned symmetrically about the center of the back to operate the rotors simultaneously.

Furthermore, the method may further include forming a fine light reflection structure on the back surface of the light guide plate using a blaster or a sander.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Example 1

2A is a schematic diagram illustrating a light guide plate according to Embodiment 1 of the present invention. This represents a light guide plate used in a planar light source device employing one light source.

Referring to FIG. 2A, one light source 10 is provided at one end of the light guide plate 100, and the light reflection structure is formed on the entire rear surface of the light guide plate 100 as a plurality of semicircles or predetermined portions of semicircles. Curved recesses and recesses are formed. At this time, the light reflecting structure forming the unevenness becomes smaller as the tangential line with respect to the light source 10 becomes farther away from the light source 10, that is, the light source 10 is installed in an open shape with respect to the light source 10. It is formed by a semicircle or a predetermined portion of a semicircle whose radius is the distance from one end to the other end facing the one end. At this time, the radius of the semi-circle is equal to the distance from one end to the other end, but may be smaller than the distance from one end to the other end.

Here, the shape of the rear surface of the light guide plate 100 formed of the light reflection structures as described above forms an overlapping arrangement such that any one of the light reflection structures selected from the light reflection structures and the plurality of light reflection structures cross each other. At this time, the number of intersection points at which the light reflection structures intersect increases as the distance from the light source 10 increases, so that the density of the entire pattern on the rear surface becomes dense in a coarse state as the distance from the light source 10 increases. It is changing. Therefore, it is possible to distribute the light evenly over the entire backside due to the increase in the amount of light reflected from the light reflection structures with the distance from the light source 10. In addition, the ratio of the pattern area of the front surface of the light guide plate 100 is high, so that the light brightness of the light guide plate is also improved.

Subsequently, a method of forming a curved recessed portion consisting of a semicircle or a predetermined portion of a semicircle in the light guide plate according to FIG. 2A will be described with reference to the drawings.

2B and 2C are schematic views showing the rotor forming the curved recessed portion according to FIG. 2A. At this time, Figure 2b is a side view of the rotor placed on the optical guide plate, Figure 2c is a plan view showing the progress operation and the rotation operation of the rotor operating in the optical guide plate. Here, the arrow of FIG. 2C shows the advancing direction and rotating direction of a rotating machine.

First, an acrylic resin plate is provided as the light guide plate 100 in which the light source 10 is installed only at one end of the above-described one.

Subsequently, referring to FIG. 2B, the rear surface of the light guide plate 100 is set as an upper surface, and a circular rotator 200 having a sanding pad attached thereto is placed on the lower surface thereof.

Next, referring to FIG. 2C, as shown in FIG. 2C, light reflection is performed by curved convex and convex portions formed by semicircles or predetermined portions of semicircles by rotating the rotor 200 in close contact with the rear surface of the light guide plate in the direction of the arrow. After forming the structure, as shown in (b) of FIG. 2C, the rotational motion is stopped and the rotor close to the rear surface is removed, and the movement is performed in parallel with the light source 10 to move by a predetermined distance. Subsequently, as shown in FIG. 2C, the rotating machine 200 is brought into close contact with each other to perform a rotating operation. By repeatedly performing the rotation operation and the advancing operation as described above, the curved light reflection structures of the semicircle or the predetermined portion of the semicircle are formed to overlap each other. In this way, the light guide plate is changed from the coarse state to the dense state as the density of the entire pattern of the light guide plate is farther from the light source.

According to the formation method of this embodiment, the shape of the curved irregularities formed on the rear surface of the light guide plate 100 is to be made of a predetermined portion of a semi-circle or semi-circle satisfying the equation (1).

Figure 2d is a plan view showing the shape of the sanding pad attached to the rotor according to the first embodiment of the present invention.

Referring to FIG. 2D, the sanding pad 210 attached to the rotator has a donut-shaped shape having a radius of the outer circumference not smaller than a distance from one end of the light guide plate to the other end facing the light guide plate. The closer it is, the better the better, and it is better to have one linear cylindrical shape with no gap between the outer and inner circumferences. Therefore, the sanding pad 210 is preferably smaller than the size of the rotor.

Example 2

3A is a schematic diagram illustrating a light guide plate according to Embodiment 2 of the present invention. This represents a light guide plate used in a planar light source device in which two light sources are employed so that light sources face each other.

Referring to FIG. 3A, the light source 10 is provided at one end of the light guide plate 100 and the other end opposite to the one end, and the light source 10 is installed at the entire rear surface of the light guide plate 100. Concave portions and convex portions are formed as curved light reflection structures composed of semicircles or predetermined portions of semicircles having a radius from the one end or the other end to the center portion A as a radius.

At this time, the back surface of the light guide plate on which the light reflection structures are formed is the first light reflection portion 110 and the first light reflection portion 110 formed on the back portion from the one end to the center portion A. ) Is divided into a second light reflecting portion 120 formed on the rear surface from the other end to the center portion A so as to be symmetrical to the same. Here, the shape of the pattern formed in the first light reflecting unit 110 and the second light reflecting unit, the light reflecting structure selected from the above-described curved light reflecting structures intersect the plurality of light reflecting structures and the light source As the distance from (10) increases, the number of intersection points due to the intersection increases. In this case, each of the light reflection structures formed in the first light reflection portion 110 and the second light reflection portion 120 is also symmetrical in the central portion (A).

Therefore, the shape of the entire rear surface of the light guide plate 100 including the first light reflecting unit 110 and the second light reflecting unit 120 is one side end of the light guide plate 100 on which the respective light sources 10 are installed. Alternatively, since the density of the pattern increases from the other end, that is, from the both ends to the center portion A, the light distribution of the entire back surface of the light guide plate can be uniform even when the light sources 10 are installed at both ends.

In addition, since the pattern of the regular arrangement made on the front surface of the light guide plate 100 increases the area ratio of the entire pattern, the brightness of the light guide plate is also improved.

Subsequently, a method of forming the main portion of the light reflection structure in the light guide plate according to FIG. 3A will be described with reference to the drawings.

3B and 3C are schematic views showing the rotors forming the first light reflecting portion and the second light reflecting portion according to FIG. 3A. In this case, Figure 3b is a side view of the position of the two rotors in the optical guide plate, Figure 3c is a plan view showing the operation and the rotation of the two rotors operating in the optical guide plate. Here, the arrows of FIG. 3C indicate the traveling direction and the rotating direction of the rotors.

First, an acrylic resin plate is provided as the light guide plate 100 in which the light source 10 is respectively installed at one side end and the other side end thereof.

Subsequently, referring to FIG. 3B, two circular rotators 200 of the same size are positioned on the rear surface of the light guide plate 100 so as to be in close contact with the rear surface while facing the center portion A of the rear surface. At this time, the sanding pad is attached to the lower surface of the circular rotor 200 as in Example 1 having uniform abrasive particles to form light reflection structures. The shape of the sanding pad is substantially the same as the outer circumference and the inner circumference. It is formed in a shape and the radius of the outer circumference is formed at least equal to the length from one side end of the light guide plate 100 to the central portion (A). At this time, the shape of the rotator 200 in this embodiment is circular to easily attach the outer periphery of the sanding pad, but may be formed into a donut shape such as a sanding pad.

Next, referring to FIG. 3C, as shown in FIG. 3C, two semi-circles or semi-circles on both sides of the two circular rotators 200 closely contacted on the light guide plate 100 are rotated together in the direction of the arrow. After forming the light reflection structures with the curved irregularities of the predetermined portion of the, as shown in (b) of FIG. 3c, the rotation operation is stopped and the rotator 200 in close contact with the rear surface is removed to perform a traveling operation in parallel with the light source. Move a certain distance. Thereafter, as shown in (c) of FIG. 3C, the rotating machines 200 are brought into close contact with each other to perform a rotating operation. By repeating the rotational motion and the advancing motion in this manner, the entire pattern of the regular array is formed on the light guide plate by the curved light reflection structures of the semicircle or the predetermined portion of the semicircle. In this case, one rotor 200 forms a pattern on the first light reflection unit 110 and the other rotor 200 forms a pattern on the second light reflection unit 120.

Here, the first light reflecting unit 110 and the second light reflecting unit 120 are each symmetrical with respect to the center portion A, and the density of the patterns formed in each of them is far from each light source. As the closer to the center portion (A) of the light guide plate 100, the two rotating parts 200 perform the rotational operation and the moving operation at the same speed so as to change from the coarse state to the dense state. In addition, in the present embodiment, two rotors 200 having the same shape and the same size are provided at the same time so that each of the rotors 200 may simultaneously form the respective light reflection parts, but only one rotor 200 is provided. The first light reflecting unit 110 and the second light reflecting unit 120 may be formed respectively.

At this time, also in this embodiment, the semicircle or the predetermined portion of the semicircle, which is the shape of the curved light reflecting structure, is a curve satisfying the above expression (1). In addition, the sanding pad may be formed only less than the length from one side end of the light guide plate 100 to the center portion A. Although the rotor 200 itself is formed in a circular shape as described above, any means for rotating may be used. Since only the sanding pads of various sizes are formed to be detachable, the size of the curve according to the size of the light guide plate can be freely adjusted by the sanding pad.

Hereinafter, embodiments of forming fine unevenness in the light guide plate according to Embodiment 1 or Embodiment 2 described above will be described with reference to the drawings.

Example 3

The present embodiment is characterized in that the fine recesses are further formed on the rear surface of the light guide plate formed in the first embodiment.

4A and 4B are schematic diagrams for describing a light guide plate according to Embodiment 3 of the present invention. 4A illustrates a light guide plate in which fine light reflection structures, that is, fine recesses are further formed on a rear surface of a light guide plate having only one light source as in Embodiment 1, and FIG. 4B illustrates a light source only on one side as in Embodiment 1 described above. It shows a method for further forming a fine light reflection structure with a blaster on the back of the light guide plate having a.

Referring to FIG. 4A, in the light guide plate 100 of the present embodiment, fine unevennesses are further formed as a fine light reflection structure on the rear surface of the light guide plate formed as shown in FIG. 2A. At this time, fine unevenness | corrugation is distributed uniformly in the whole back surface.

Referring to FIG. 4B, on the light guide plate on which the curved light reflection structures are formed in the same manner as in Example 1, the blasters 310, 320, and 330 move in parallel with the light source 10 installed at one end thereof. Spray the toner 400 to the (100). In FIG. 4B, the arrows indicate the moving directions of the blasters 310, 320, and 330.

Example 4

The present embodiment is characterized in that the fine light reflecting structures are further formed on the rear surface of the light guide plate formed in Example 2 described above.

5A and 5B are schematic diagrams for describing a light guide plate according to Embodiment 4 of the present invention. FIG. 5A illustrates a light guide plate in which fine light reflection structures are further formed on a rear surface of a light guide plate having light sources at both ends as in Embodiment 2 described above, and FIG. 5B is a light guide plate having light sources at both ends as in Embodiment 2 described above. It shows how to further form the fine light reflecting structures with the blaster on the back of.

Referring to FIG. 5A, the light guide plate 100 of the present embodiment has a rear surface of the light guide plate having light sources 10 at both ends thereof, that is, the first light reflecting unit 110 and the second light reflecting unit 120 as shown in FIG. 3A. After the curved light reflecting structures are formed in, fine irregularities are further formed as the light reflecting structure. At this time, the fine irregularities are uniformly distributed over the entire back surface.

Referring to FIG. 5B, the blasters 310, 320, and 330 move in parallel with the light source 10 installed at one end and the other end on the light guide plate on which the curved light reflection structures are formed in the same manner as in the second embodiment. While injecting the duct 400 to the light guide plate (100).

In Examples 3 and 4, the density of the fine light reflecting structures formed by the blasting agent of the blaster is formed to be uniform throughout, but the density of the fine light reflecting structures is far from the light source 10. It may change from a sparse state to a dense state.

At this time, in the third and fourth embodiments, the movement of the blasters is moving in a direction parallel to the light source, but may be moved in the vertical direction.

In addition, although the blaster is used as a method of forming fine light reflection structures in Example 3 and Example 4, sanders with abrasive grains may be used.

Example 5

6A is a schematic diagram illustrating a light guide plate according to Embodiment 5 of the present invention. This represents a light guide plate used in a planar light source device employing one light source.

Referring to FIG. 6A, one light source 10 is provided at one end of the light guide plate 100, and the light reflection structure is formed on the entire rear surface of the light guide plate 100 as a semi-ellipse or a semi-ellipse. Curved recesses and recesses are formed. At this time, the light reflecting structure forming the unevenness becomes smaller as the tangential line with respect to the light source 10 becomes farther away from the light source 10, that is, the light source 10 is installed in an open shape with respect to the light source 10. The distance from one side end to the other end opposite to the one end is half the length of the short axis and is formed of a predetermined portion of a semi-ellipse or semi-ellipse having a constant long axis length. In addition, although half of the short axis length is made into the distance from one end to the other end in this embodiment, it is not necessary to be smaller than the distance from one end to the other end.

Here, the shape of the rear surface of the light guide plate 100 formed of the light reflection structures as described above forms an overlapping arrangement such that any one of the light reflection structures selected from the light reflection structures and the plurality of light reflection structures cross each other. At this time, since the number of intersection points at which the light reflection structures cross is increased as the distance from the light source increases, the density of the entire pattern of the rear surface is changed from a coarse state to a dense state as the distance from the light source 10 increases. . This increases the amount of light reflected by the light reflecting structures according to the distance from the light source 10, so that the light can be uniformly distributed on the entire back surface, and the pattern area ratio of the front surface of the light guide plate 100 is also increased. It becomes high and the light brightness as a light guide plate also improves.

Subsequently, a method of forming a main portion consisting of a semi-elliptic curve or a predetermined portion of the semi-ellipse in the light guide plate according to FIG. 6A which is the present embodiment will be described with reference to the drawings.

FIG. 6B is a schematic diagram illustrating a rotator forming the curved recesses according to FIG. 6A. This is a plan view showing the advancing and rotating operation of the rotator operating in the light guide plate. Here, the arrow of FIG. 6B shows the advancing direction and rotational direction of a rotating machine.

First, an acrylic resin plate is provided as the light guide plate 100 in which the light source 10 is installed only at one end of the above-described one.

Subsequently, as shown in FIG. 2B of Embodiment 1, the back surface of the light guide plate 100 is set as an upper surface, and a circular rotator 200 having a sanding pad attached thereto is placed on the lower surface thereof. At this time, the sanding pad has a donut shape as shown in FIG. 2D.

Next, referring to FIG. 6B, as shown in FIG. 6B (a), the rotating operation 200 closely attached to the rear surface of the light guide plate 100 may be rotated in the direction of an arrow and the moving operation may be performed at a constant speed in parallel with the light source, respectively. At the same time, as shown in (b) of FIG. 6B, one light reflection structure is formed by curved irregularities formed by a semi-ellipse or a predetermined portion of the semi-ellipse by moving by a predetermined interval in a progressive operation performed during one rotation. will be. Subsequently, as shown in FIG. 6B, the next rotational operation is performed at a constant speed and the advancing operation is performed at a constant speed to form a curved light reflection structure having the same shape so as to overlap the formed light reflection structure. .

As described above, the rotation progressing operation and the progressing operation are continuously performed at the same time, thereby forming a shape in which the curved light reflection structures of the semi-ellipse or the predetermined portion of the semi-ellipse are overlapped constantly. The shape of the entire pattern changes the pattern density from the coarse state to the dense state as the distance from the light source 10 increases, thereby forming a light guide plate capable of achieving a uniform light distribution.

Here, the shape of the curved concavo-convex formed in the light guide plate 100 according to the method of the present embodiment is made of a predetermined portion of the semi-ellipse or semi-ellipse satisfying the equation (2) by simultaneously performing the rotation operation and the advance operation. At this time, the faster the speed of the advance operation than the speed of the rotation operation, the longer the long axis.

Example 6

7A is a schematic view illustrating a light guide plate according to Embodiment 6 of the present invention. This represents a light guide plate used in a planar light source device in which two light sources are employed so that the light sources face each other.

Referring to FIG. 7A, the light source 10 is provided at one end of the light guide plate 100 and the other end opposite to the one end, and the light source 10 is installed at the entire rear surface of the light guide plate 100. The recessed portion and the convex portion are formed as curved light reflection structures composed of semi-ellipse or a predetermined portion of a semi-ellipse having a distance from one side end or the other end to half of the short axis length and having a constant major axis length. Here, half of the short axis length may be made smaller than the distance from the one end or the other end to the center portion A. In other words, it is good if the shortened length is not smaller than the distance from one end to the other end.

At this time, the back surface of the light guide plate 100 on which the light reflection structures are formed is a first light reflection unit 110 and a first light reflection centering around the center portion A and the first light reflection portion 110 formed at the back side from the one end to the center portion A. FIG. It is divided into a second light reflecting portion 120 formed on the rear surface from the other end to the central portion (A) to be symmetrical with the portion (110). Here, the shape of the pattern formed in the first light reflecting unit 110 and the second light reflecting unit, the light reflecting structure selected from the above-described curved light reflecting structures intersect the plurality of light reflecting structures and the light source As the distance from (10) increases, the number of intersection points due to the intersection increases. In this case, each of the light reflection structures formed in the first light reflection portion 110 and the second light reflection portion 120 is also symmetrical in the central portion (A).

Therefore, the shape of the entire rear surface of the light guide plate 100 including the first light reflecting unit 110 and the second light reflecting unit 120 is one side end of the light guide plate 100 on which the respective light sources 10 are installed. Alternatively, since the density of the pattern increases from the other end, that is, from both ends to the center portion A, the light distribution of the entire back surface of the light guide plate can be made uniform even when the light sources 10 are installed at both ends. In addition, since the pattern of the regular arrangement made on the front surface of the light guide plate 100 increases the area ratio of the entire pattern, the brightness of the light guide plate is also improved.

Subsequently, a method of forming the main portion of the light reflection structure composed of a semi-ellipse or a predetermined portion of the semi-ellipse in the light guide plate according to FIG. 7A will be described with reference to the drawings.

FIG. 7B is a schematic diagram illustrating the rotators forming the first light reflecting portion and the second light reflecting portion according to FIG. 7A. This is a plan view showing the advancing and rotating motions of the two rotors operating in the light guide plate. Here, the arrows in FIG. 7B indicate the traveling direction and the rotating direction of the rotors.

First, an acrylic resin plate is provided as the light guide plate 100 in which the light source 10 is respectively installed at one side end and the other side end thereof.

Subsequently, as shown in FIG. 3B of Embodiment 2, two circular rotators 200 of the same size are mounted on the rear surface of the optical guide plate 100 so as to be in close contact with the rear surface while facing the center portion A of the rear surface. Position it. At this time, the bottom surface of the circular rotor 200 is attached to a sanding pad, such as used in Example 1 having a uniform abrasive particles to form light reflection structures, the shape of the sanding pad is almost identical to the outer circumference It is made of a donut-shaped as shown in Figure 2d and the radius of the outer circumference is formed to be at least the length from one side end of the light guide plate 100 to the central portion (A). At this time, the shape of the rotator 200 in this embodiment is circular to easily attach the outer periphery of the sanding pad, but may be formed into a donut shape such as a sanding pad.

Next, referring to FIG. 7B, as shown in (a) of FIG. 7B, the two circular rotators 200 closely contacted on the light guide plate 100 may be rotated together at a constant speed in a direction of an arrow and a constant speed may be advanced. The operation is performed, and as shown in (b) of FIG. 7B, the traveling operation is performed in parallel with the light source during one rotation operation in each of the rotors 200, thereby forming light reflection structures that are symmetrical to each other. Subsequently, as shown in (c) of FIG. 7B, the next light reflecting structures are formed to overlap with the first light reflecting structures when the next rotational and traveling operations are performed.

As described above, by simultaneously performing the rotation operation and the progress operation, the entire pattern is formed on the rear surface of the light guide plate 100 in a shape in which the curved light reflection structures of the semi-ellipse or the predetermined portion of the semi-ellipse are overlapped regularly. At this time, one rotating machine 200 forms the first light reflecting unit 110 and the other rotating unit 200 forms the second light reflecting unit 120.

Here, each of the first light reflecting unit 110 and the second light reflecting unit 120 is symmetrical with respect to the center portion A, so that the density of the patterns formed in each of them is a distance from each light source 10. The farther away and closer to the central portion (A) of the light guide plate 100, so that the two rotors 200 perform the rotational operation and the moving operation at the same speed so as to change from a coarse state to a dense state. In addition, in the present embodiment, two rotors 200 having the same shape and the same size are provided at the same time so that each of the rotors 200 may simultaneously form the respective light reflection parts, but one rotor 200 is operated. The first light reflecting unit 110 and the second light reflecting unit 120 may be formed respectively.

At this time, the semi-ellipse or the predetermined portion of the ellipse which is the shape of the curved light reflection structure is a curve satisfying the above expression (2). In addition, the sanding pad may be formed only less than the length from one side end of the light guide plate 100 to the center portion A. Although the rotor 200 itself is formed in a circular shape as described above, any means for rotating may be used. Since only the sanding pads of various sizes are formed to be detachable, the size of the curve according to the size of the light guide plate can be freely adjusted by the sanding pad.

As described above, the embodiments of the present invention have a shape in which the first light reflecting unit 110 and the second light reflecting unit 120 have extreme shapes so that the fluorescent reflecting structures may be formed. Since the intersections do not meet at the center portion A, the phenomenon in which the first light reflection portion 110 and the second light reflection portion 120 overlap at the center does not occur. Therefore, even if the distance from the light source 10 is far, the amount of scattered and reflected light in the light guide plate is made uniform.

Example 7

8A is a schematic diagram illustrating a light guide plate according to Embodiment 7 of the present invention. This represents a light guide plate used in a planar light source device employing one light source.

Referring to FIG. 8A, one light source 10 is provided at one end of the light guide plate 100, and as a light reflection structure on the entire rear surface of the light guide plate 100, a plurality of semicircles or predetermined portions of the semicircles are provided. The formed curved recesses and convex portions are formed. At this time, the light reflecting structure forming the unevenness becomes smaller in the tangent line with respect to the light source 10 as the further away from the light source 10, that is, open to the light source 10, the same origin having different radii Are formed of semicircles or portions of the semicircles. At this time, the radius of the semi-circle located in the outermost of the above-described semicircles has a length not less than the distance from one side end to the other end facing the one end.

Here, the number of intersection points at which one of the outermost light reflecting structures selected from the outermost light reflecting structures intersects the plurality of reflecting structures increases as the distance from the light source 10 increases, so that the density of the entire pattern of the rear surface is increased. As the distance from the light source 10 increases, it changes from a sparse state to a dense state. This makes it possible to distribute the light evenly over the entire back surface with an increase in the amount of light reflected from the light reflection structures according to the distance from the light source 10. In addition, between the outermost light reflection structures, a light pattern forms an overlapping arrangement such that any one of the light reflection structures selected from the light reflection structures and the plurality of light reflection structures cross each other. For this reason, the pattern area ratio of the front surface of the light guide plate 100 is high, and the light brightness as a light guide plate is also improved.

Subsequently, a method of forming the main portion of the light reflection structure in the light guide plate according to FIG. 8A will be described.

In this case, the light reflection structure forming method of Example 1, but is carried out by replacing the sanding pad as follows. Here, the shape of the sanding pad attached to the rotor will be described with reference to the drawings.

8B is a plan view illustrating the shape of the sanding pad according to the seventh embodiment.

Referring to FIG. 8B, the sanding pad 210 is circular in which uniform abrasive particles are formed. Here, the size of the sanding pad 210 should not be less than the size of the rotator, the radius should be a length not smaller than the distance from one end of the light guide plate to the other end.

In this embodiment, the outermost peripheral portion of the circular sanding pad is further forced to perform a rotation operation. Then, the pattern etching of the outermost curved light reflection structures is made deeper. In this case, thin fine curved light reflecting structures are formed in the remaining part of the rear surface of the light guide plate, thereby improving the uniformity of the light and at the same time, forming a pattern in which the brightness is also improved, as in Example 3 or Example 4 It is not necessary to form more reflective structures.

Example 8

9 is a schematic diagram illustrating a light guide plate according to Embodiment 8 of the present invention. This represents a light guide plate used in a planar light source device in which two light sources are employed so that the light sources face each other.

9, light sources 10 are provided at one end of the light guide plate 100 and the other end opposite to the one end, respectively, and have the same origin having different radii on the entire rear surface of the light guide plate 100. Concave and convex portions are formed as curved light reflecting structures consisting of semicircles of or predetermined portions of the semicircles. Here, the radius of the semicircle located at the outermost of the semicircles has a length not smaller than the distance from one end or the other end to the center portion, and is formed with a deeper vertical etching than the other light reflecting structures.

At this time, the back surface of the light guide plate 100 on which the light reflection structures are formed is a first light reflection unit 110 and a first light reflection centering around the center portion A and the first light reflection portion 110 formed at the back side from the one end to the center portion A. FIG. It is divided into a second light reflecting portion 120 formed on the rear surface from the other end to the central portion (A) to be symmetrical with the portion (110). Here, the shape of the pattern formed by the first light reflecting unit 110 and the second light reflecting unit, the outermost light reflecting structure selected from the above-mentioned curved outermost light reflecting structure is a plurality of light reflecting structures Intersecting with and forming an array in which the number of intersection points due to the intersection increases as the distance from the light source 10 increases. At this time, the remaining light reflecting structures are also finely formed between the outermost light reflecting structures at which one light reflecting structure selected from the light reflecting structures intersects with the plurality of light reflecting structures to form intersection points. At this time, each of the light reflection structures formed in the first light reflection portion and the second light reflection portion 120 is also symmetrical in the center portion (A).

Therefore, the shape of the entire rear surface of the light guide plate 100 including the first light reflecting unit 110 and the second light reflecting unit 120 is one side end of the light guide plate 100 on which the respective light sources 10 are installed. Alternatively, since the density of the pattern increases due to the outermost light reflecting structure from the other end, that is, from the both ends to the center portion A, fine curved light reflecting structures are formed between the outermost light reflecting structures, Also in the case where 10) is provided, the brightness of the light is also improved in addition to making the light distribution of the entire back surface of the light guide plate uniform. At this time, it is not necessary to further form the fine light reflection structure as in Example 4.

Subsequently, a method of forming the main portion of the light reflection structure in the light guide plate according to the ninth embodiment will be described.

At this time, it is formed by the forming method of the second embodiment using the rotary sanders attached to the circular sanding pad as shown in Figure 8c of the seventh embodiment. Here, as in the seventh embodiment, the rotational operation should be performed by applying more force to the outermost peripheral portion of the circular sanding pad.

Further, the light reflection structures as curves composed of semicircles or predetermined portions of semicircles of Examples 7 and 8 satisfy Equation (1).

Example 9

In the present embodiment, patterns on the back surface of the light guide plate are made up of predetermined portions of semi-ellips or semi-ellipses having a constant ratio of lengths of short axis and long axis at the same origin and different sizes. At this time, half of the length of the short axis of the semi-ellipse positioned at the outermost of the semi-ellips is formed so as not to be less than the distance from one end to the other end facing the one end. As in Example 7, the outermost light reflection structures and the remaining light reflection structures form a plurality of intersection points.

In addition, the light guide plate formation method in this Example is performed by the light reflection structure formation method of Example 5, but replaces the sanding pad with the shape like FIG. 8B. Here, the outer and outer peripheral portion of the circular sanding pad should be given more force to perform the rotation operation and the operation.

Example 10

In the present embodiment, patterns on the rear surface of the light guide plate are made of semi-ellips or predetermined portions of the semi-ellips having different lengths and constant sizes of short axis and long axis at the same origin. The length of the short axis of the semi-ellipse positioned at the outermost of the semi-ellips is not less than the distance from one end to the other end, and as shown in Example 8, the outermost light reflection structures and the remaining light reflection structures It will form an intersection.

In addition, the light guide plate formation method in this Example is implemented by the light reflection structure formation method of Example 6, but replaces the sanding pad with the shape like FIG. 8B. Here, the outer and outer peripheral portion of the circular sanding pad should be given more force to perform the rotation operation and the operation.

The light reflection structures as the curve consisting of the semi-ellipse or the semi-ellipse of the above-described Embodiments 9 and 10 satisfy the equation (2).

[Examples 11 and 12]

Example 11 is to form a fine light reflecting structure on the back of the light guide plate according to Example 5 as in Example 3, Example 12 is a fine light reflecting structure as in Example 4 on the back of the light guide plate according to Example 6 To form more.

According to the light guide plate and the manufacturing method according to the present invention as described above, by simply forming a light reflection structure having a semi-circular curve or a predetermined curved irregularities of the semi-circle on the light guide plate, it is possible to provide a light guide plate with improved light brightness and light uniformity. Therefore, it can make a big contribution to the surface light source device industry.

Further, when the fine concave portion is further formed on the light guide plate to form the curved concave-convex light reflecting structure and the fine concave-convex light reflecting structure in combination, the area ratio of the pattern is increased, so that the improved light brightness and light uniformity can be obtained, and the conventional ink pattern The light guide plate without shape deformation in the light reflection structure as in the above can be easily obtained.

The present invention is not limited to the above embodiments, and it is apparent that many modifications are possible by those skilled in the art within the technical spirit of the present invention.

Claims (26)

A light guide plate having a light source installed at at least one end thereof; And a curved light reflecting structure formed on a rear surface of the light guide plate, the curved light reflecting structures comprising a semicircle open to the light source or a predetermined portion of the semicircle. The light source of claim 1, wherein the light source is installed at only one end of the light guide plate; The light reflecting structures are formed on the entire rear surface of the light guide plate and have a radius of a length not smaller than a distance from the one end to which the light source is installed to the other end opposite to the one end, the predetermined radius of the semicircle or the semicircle. And a light reflecting structure selected from the light reflecting structures to intersect with the plurality of light reflecting structures, and as the distance from the light source increases, the number of intersection points due to the crossing increases. Light guide plate characterized in that. The light source of claim 1, wherein the light sources are provided at one end and the other end of the light guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the central portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflecting structures may comprise: a semicircle or a predetermined portion of the semicircle having a radius of a length not smaller than a distance from the one end or the other end to which the light source is installed, to the center portion, and from the light reflecting structures The selected light reflecting structure intersects with the plurality of light reflecting structures, wherein the light guide plate is formed such that the number of intersection points due to the crossing increases as the distance from the light source increases. The light guide plate according to any one of claims 1 to 3, wherein fine light reflection structures are further formed on the rear surface thereof. The light source of claim 1, wherein the light source is installed at only one end of the light guide plate; The light reflecting structures are formed on the entire back surface of the light guide plate, and are composed of semicircles of the same origin having different radii or predetermined portions of the semicircles, wherein the semicircles located at the outermost sides of the semicircles are the one end. A radius of a length not smaller than a distance from the other end to the one end opposite to the other end, wherein any one of the light reflecting structure selected from the light reflecting structures intersects with the plurality of light reflecting structures to form intersection points. Light guide plate made with. The light source of claim 1, wherein the light sources are provided at one end and the other end of the light guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflecting structures may comprise: semicircles of the same origin having different radii, or predetermined portions of the semicircles, wherein the semicircle located at the outermost part of the semicircles is the distance from the one end or the other end to the center portion. A light guide plate having a length less than a radius, wherein any one of the light reflection structures selected from the light reflection structures intersects with the plurality of light reflection structures to form intersection points. A light guide plate having a light source installed at at least one end thereof; And a curved light reflecting structure formed on a rear surface of the light guide plate, the curved light reflecting structures comprising a half ellipse or a predetermined portion of the half ellipse. The light source of claim 7, wherein the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire rear surface of the light guide plate, the length of which is not smaller than the distance from the one end to which the light source is installed to the other end opposite to the one end is half the length of the short axis and has a constant long axis length. The semi-ellipse having a portion or a predetermined portion of the semi-ellipse, and any one of the light reflecting structure selected from the light reflecting structure intersects the plurality of light reflecting structures, the farther away from the light source A light guide plate, characterized in that formed to increase the number of intersections due to intersection. 8. The light emitting apparatus according to claim 7, wherein the light sources are respectively provided at one end and the other end of the light guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflection structures may include a half ellipse having a predetermined long axis length or a predetermined portion of the semi ellipse having a length not smaller than a distance from the one end or the other end to which the light source is installed to the center. The light reflecting structure selected from the light reflecting structures intersects with the plurality of light reflecting structures, and as the distance from the light source increases, the number of intersection points due to the crossing increases. Light guide plate made with. The light guide plate according to any one of claims 7 to 9, wherein fine light reflection structures are further formed on the rear surface thereof. The light source of claim 7, wherein the light source is installed only at one end of the light guide plate; The light reflecting structures are formed on the entire back surface of the light guide plate, and are composed of semi-ellips or predetermined portions of the semi-ellips having different lengths and constant sizes of short axis and long axis at the same origin. The semi-ellipse positioned at the outermost side has a length that is not smaller than the distance from the one end to the other end facing the one end, and the half length of the short axis length, and any one light reflection structure selected from the light reflection structures Light guide plate, characterized in that the intersection with the light reflecting structures are formed. 8. The light emitting apparatus according to claim 7, wherein the light sources are respectively provided at one end and the other end of the light guide plate facing each other; The rear surface of the light guide plate may include: a first light reflecting portion where the light reflecting structures are formed on the back surface from the one end to the center portion, and the other end so as to be symmetrical with the first light reflecting portion with respect to the center portion; A second light reflecting portion in which the light reflecting structures are formed on the back side to the center portion of the light reflecting member; The light reflection structures include: semi-ellips having a constant ratio of short axis and long axis at the same origin and having different sizes or predetermined portions of the semi-ellips, wherein the semi-ellipse positioned at the outermost of the semi-ellipses is the one side. A length of not smaller than the distance from the end to the other end is a shortened length, and any one of the light reflection structures selected from the light reflection structures intersects with the plurality of light reflection structures to form intersection points. Light guide plate. Providing a light guide plate on which at least one end of the light source is installed; At least one rotator having a sanding pad provided with abrasive particles on the rear surface of the optical induction plate, the rotational movement and the progressing operation that proceeds in parallel with the light source are repeatedly performed at a constant speed to form a semicircle or a predetermined portion of the semicircle. A method of manufacturing a light guide plate comprising forming curved light reflection structures. The light source of claim 13, wherein the light source is installed at only one end of the light guide plate; The sanding pad of the rotator, the method of manufacturing a light guide plate, characterized in that the donut-shaped shape having a radius of the outer circumference of a length not smaller than the distance from the one end to the other end facing the one end. The light source of claim 13, wherein the light source is installed at only one end of the light guide plate; The sanding pad of the rotator is a manufacturing method of the light guide plate, characterized in that the circular shape having a radius of not less than the distance from the one end to the other end facing the one end. The method of claim 13, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator is a manufacturing method of the light guide plate, characterized in that the circular shape having a radius of not less than the distance from the one end to the center of the rear surface. The method of claim 13, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator is a method of manufacturing a light guide plate, characterized in that the donut shape having a radius of the outer circumference of a length not smaller than the distance from the one end to the center portion of the back. The method of claim 13, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; Wherein the rotor is provided with two, the sanding pad of each of the rotor is positioned to be symmetrical about the central portion of the rear surface of the manufacturing method of the light guide plate, characterized in that for operating the rotor at the same time. The method of claim 13, further comprising forming a fine light reflection structure on the back surface of the light guide plate using a blaster or a sander. Providing a light guide plate on which at least one end of the light source is installed; At least one rotator provided with sanding pads provided with abrasive particles on the rear surface of the light guide plate, and simultaneously performs a rotation operation and a traveling operation that proceeds in parallel with the light source at a constant speed, and thus a half ellipse or a predetermined portion of the semi ellipse. Method of manufacturing a light guide plate comprising the step of forming a curved light reflecting structure consisting of. 21. The method of claim 20, wherein the light source is installed on only one end of the light guide plate; The sanding pad of the rotator, the method of manufacturing a light guide plate, characterized in that the donut-shaped shape having a radius of the outer circumference of a length not smaller than the distance from the one end to the other end facing the one end. 21. The method of claim 20, wherein the light source is installed on only one end of the light guide plate; The sanding pad of the rotator is a manufacturing method of the light guide plate, characterized in that the circular shape having a radius of not less than the distance from the one end to the other end facing the one end. 21. The method of claim 20, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator is a manufacturing method of the light guide plate, characterized in that the circular shape having a radius of not less than the distance from the one end to the center of the rear surface. 21. The method of claim 20, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; The sanding pad of the rotator is a method of manufacturing a light guide plate, characterized in that the donut shape having a radius of the outer circumference of a length not smaller than the distance from the one end to the center portion of the back. 21. The method of claim 20, wherein the light source is installed on one side end and the other end of the light guide plate facing each other; Wherein the rotor is provided with two, the sanding pad of each of the rotor is positioned to be symmetrical about the central portion of the rear surface of the manufacturing method of the light guide plate, characterized in that for operating the rotor at the same time. 21. The method of claim 20, further comprising forming a fine light reflection structure on the back surface of the light guide plate with a blaster or a sander.