CN115857265A - Projector Optical System - Google Patents

Abstract

The application discloses projector optical system, this projector optical system includes: light source, first compensating element, second compensating element and curtain, wherein: the first compensation element is arranged on the light emitting side of the light source and used for compensating the phase difference of emergent light of the light source in a first direction, wherein the first direction is the direction in which the emergent light of the light source penetrates through the first compensation element; the second compensation element is arranged on the light emitting side of the first compensation element and used for compensating the phase difference of emergent light of the first compensation element in a second direction, wherein the second direction is a direction perpendicular to the first direction; the emergent light of the second compensation element is projected to the curtain.

Description

Projector Optical System

technical field

The present application relates to the technical field of projection display, in particular to a projector optical system.

Background technique

As people's demands for entertainment change, projectors as large-screen projection devices are more and more widely used in daily life. In the related art, the light is compensated by setting a quarter-wave plate (QWP) in the optical system of the projector. However, since the QWP can only partially compensate the light, the projection in the related art The machine optical system has the problem of light leakage at large viewing angles.

Contents of the invention

The present application discloses an optical system of a projector, which can solve the problem of light leakage at a large viewing angle existing in the optical system of the projector.

In order to solve the above problems, the application adopts the following technical solutions:

The embodiment of the present application discloses a projector optical system, including: a light source, a first compensating element, a second compensating element, and a screen, wherein: the first compensating element is arranged on the light output side of the light source for The phase difference of the outgoing light of the light source in the first direction is compensated, wherein the first direction is the direction in which the outgoing light of the light source passes through the first compensation element; the second compensation element is arranged on the The light exit side of the first compensation element is used to compensate the phase difference of the exit light of the first compensation element in the second direction, wherein the second direction is a direction perpendicular to the first direction; The outgoing light of the second compensating element is projected onto the screen.

An embodiment of the present application provides an optical system for a projector, by arranging a first phase difference on the light output side of the light source for compensating the phase difference A compensation element, a second compensation element for compensating the phase difference in a second direction perpendicular to the first direction is arranged on the light output side of the first compensation element, and the light emitted by the light source passes through the first compensation element, the second compensation element, and the second compensation element in sequence. The components are projected onto the screen, which can avoid light leakage from the large viewing angle of the projector optical system.

Description of drawings

FIG. 1 is a schematic structural diagram of a projector optical system disclosed in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a projector optical system disclosed in an embodiment of the present application.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

The terms "first", "second" and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific sequence or sequence. It should be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application can be practiced in sequences other than those illustrated or described herein, and that references to "first," "second," etc. distinguish Objects are generally of one type, and the number of objects is not limited. For example, there may be one or more first objects. In addition, "and/or" in the specification and claims means at least one of the connected objects, and the character "/" generally means that the related objects are an "or" relationship.

FIG. 1 is a schematic structural diagram of a projector optical system disclosed in an embodiment of the present application, and FIG. 2 is a structural schematic diagram of a projector optical system disclosed in an embodiment of the present application.

As shown in Figures 1 and 2, the projector optical system disclosed in the embodiment of the present application includes: a light source 110, a first compensating element 120, a second compensating element 130, and a screen 140, wherein: the first compensating element 120 is set On the light output side of the light source 110, it is used for compensating the phase difference of the outgoing light of the light source 110 in the first direction, wherein the first direction is that the outgoing light of the light source 110 passes through the first The direction of the compensating element 120; the second compensating element 130 is arranged on the light exit side of the first compensating element 120, and is used to compensate the phase difference of the outgoing light of the first compensating element 120 in the second direction, Wherein, the second direction is a direction perpendicular to the first direction; the outgoing light of the second compensating element 130 is projected onto the screen 140 .

In this application, the first direction is the direction in which the light emitted from the light source 110 passes through the first compensation element 120, that is to say, the first direction is the thickness direction of the first compensation element 120, and the second direction is the The thickness direction of 120 is perpendicular to the direction.

In this application, the light emitted by the light source 110 sequentially passes through the first compensating element 120 for compensating the phase difference of the outgoing light of the light source 110 in the first direction, and for compensating the outgoing light of the first compensating element 120 in the The second compensating element 130 that compensates the phase difference in the second direction perpendicular to the first direction is then projected onto the screen 140 , which can solve the problem of light leakage at a large viewing angle in the optical system of the projector.

The embodiment of the present application provides an optical system for a projector, by setting a device on the light output side of the light source 110 for adjusting the phase difference of the output light of the light source 110 in the first direction in which the output light of the light source 110 passes through the first compensating element 120 The first compensating element 120 for compensation, the second compensating element 130 for compensating the phase difference in the second direction perpendicular to the first direction is arranged on the light output side of the first compensating element 120, and the light emitted by the light source 110 passes through the The first compensating element 120 and the second compensating element 130 are projected onto the screen 140, which can avoid light leakage at a large viewing angle of the optical system of the projector.

In one implementation, as shown in Figures 1 and 2, the projector optical system may further include a reflective optical cup 150, a first lens 160, a reflective polarizer 170, a polarizer 180, and a display 190, wherein: The reflective optical cup 150 is disposed on the light emitting side of the light source 110, the first lens 160 is disposed on the light emitting side of the reflective optical cup 150, and the first compensation element 120 is disposed on the first lens 160. On the light exit side, the reflective polarizer 170 is arranged on the light exit side of the second compensation element 130, the polarizer 180 is arranged on the light exit side of the reflective polarizer 170, and the display 190 is arranged on the On the light output side of the polarizer 180 , the output light of the display 190 is projected onto the screen 140 .

The outgoing light of the light source 110 diverges to the first lens 160 through the reflective light cup 150, and the first lens 160 collimates the outgoing light of the light source 110 into multiple beams of parallel light, and the multiple beams of parallel light The light sequentially passes through the first compensation element 120, the second compensation element 130 and the reflective polarizer 170 to reach the polarizer 180, and the polarizer 180 decomposes the multiple beams of parallel light into P light and S light, the P light passes through the display 190 and is projected to the screen 140, the S light is reflected back to the second compensation element 130 by the reflective polarizer 170, because the second compensation element 130 is also used to rotate the transmission axis of the S light by 90° so that the S light is converted into right-handed circularly polarized light, therefore, the S light passes through the second compensation element 130 and is converted into right-handed circularly polarized light, and then The right-handed circularly polarized light sequentially passes through the first compensation element 120 and the first lens 160 to reach the reflective optical cup 150, and is reflected and converted into left-handed circularly polarized light by the reflective optical cup 150, the The left-handed circularly polarized light sequentially passes through the first lens 160 and the first compensation element 120 to reach the second compensation element 130, since the second compensation element 130 is also used to convert the left-handed circularly polarized light into P light, therefore , the left-handed circularly polarized light passes through the second compensation element 130 and is converted into P light. Since the transmission axis of the converted P light is consistent with the transmission axis of the reflective polarizer 170, the converted P light can pass through The reflective polarizer 170 then continues to pass through the display 190 and project to the screen 140 , which can effectively improve the utilization rate of the light efficiency of the light source 110 .

In another possible solution, the reflective light cup 150 is arranged on the light emitting side of the light source 110, the first compensation element 120 is arranged on the light emitting side of the reflective light cup 150, and the reflective polarized light The element 170 is disposed on the light exit side of the second compensation element 130, the polarizer 180 is disposed on the light exit side of the reflective polarizer 170, and the first lens 160 is disposed on the light exit side of the polarizer 180. On the side, the display 190 is disposed on the light emitting side of the first lens 160 , and the outgoing light of the display 190 is projected onto the screen 140 . In this case, the processing of light by the polarizer 180 , the reflective polarizer 170 , the second compensation element 130 and the reflective optical cup 150 is consistent with the above, and will not be repeated in this application.

In the embodiment of the present application, as shown in FIG. 2 , the above-mentioned projector optical system may further include a second lens 1110, a mirror 1120, and a lens 1130. The second lens 1110 is arranged on the light-emitting side of the display 190. The outgoing light is reflected by the mirror 1120 to the lens 1130 , and finally projected to the curtain 140 , where the image is formed. It should be noted that both the first lens 160 and the second lens 1110 are used to change the divergent light into a collimated light beam, so that the outgoing light is uniform.

In an implementation manner, the reflective cup 150 may be a prism-shaped or circular-truncated reflective cup.

In an implementation manner, both the first lens 160 and the second lens 1110 can be Fresnel lenses to reduce costs, wherein the surface of the first lens 160 away from the reflective cup 150 is a flat surface, and the surface of the second lens 1110 close to The surface of the display 190 is a flat surface. Further, the first anti-reflection anti-reflection element can also be arranged on the flat surface of the Fresnel lens. Exemplarily, the first anti-reflection anti-reflection element can be an anti-reflection anti-reflection film, that is, on the Fresnel lens Add anti-reflection and anti-reflection coating to the flat surface of the Fresnel lens, that is, to perform AR surface treatment on the flat surface of the Fresnel lens to improve the light efficiency of the projector optical system. In addition, the first lens 160 and the second lens 1110 may also be other lenses capable of realizing corresponding functions, which is not specifically limited in this application.

In an implementation manner, the reflective polarizer 170 may be a reflective polarizer (Reflective Polarizer, RP) or a brightness enhancement reflective polarizer (dual brightness enhancement film, DBEF). The reflective polarizer 170 described herein may also be other reflective polarizer structures, which are not specifically limited in this application.

In one implementation manner, the polarizer 180 may be a polarizer (polarizer, POL).

In an implementation manner, the display 190 may be a liquid crystal display (Liquid Crystal Display, LCD).

In the embodiment of the present application, the projector optical system described above may further include a heat insulating glass 1100 disposed between the light source 110 and the first compensating element 120 . By arranging the heat insulating glass 1100 on the light emitting side of the light source 110, the heat generated by the light source 110 can be avoided from affecting the entire optical system of the projector.

In an implementation manner, the projector optical system described above may further include a second anti-reflection and anti-reflection element, and the second anti-reflection and anti-reflection element is disposed on the surface of the insulating glass 1100 . Exemplarily, the second anti-reflection and anti-reflection component may be an anti-reflection and anti-reflection film, that is, an anti-reflection and anti-reflection film is added to the surface of the heat insulating glass 1100, that is, AR surface treatment is performed on the surface of the heat insulating glass 1100, To improve the light efficiency of the projector optical system.

In a possible implementation solution, the first compensation element 120 is a C plate, and the second compensation element 130 is a quarter-wave plate.

Exemplarily, a quarter-wave plate (quarter-wave plate, QWP) can be a reverse dispersion (reversewavelength dispersion, RWD) QWP, and the QWP is a retardation film coated by liquid crystal, and the pretilt angle of the liquid crystal is 0 °, the refractive index of the film is nx<ny=nz. It should be noted that QWP is a retardation film whose optical axis is parallel to the surface of the film, that is, A plate.

Exemplarily, C plate can be RWD C plate, and this C plate is the retardation film coated by liquid crystal, and the pretilt angle of its liquid crystal is 90 °, and the refractive index of this film is nx=ny>nz, because C plate can Compensate oblique light leakage in the dark state to expand the viewing angle. Therefore, by using the C plate as a compensation film for the quarter-wave plate, the problem of light leakage at large viewing angles in the projector optical system can be solved. It should be noted that the optical axis of C plate is perpendicular to the surface of the film.

In an implementation manner, the quarter-wave plate may be a wide-band quarter-wave plate, which can allow more light to pass through and improve the light efficiency of the optical system of the projector. Certainly, the QWP may also be a QWP in a narrow wave domain, which is not specifically limited in this application.

In the embodiment of the present application, the light source 110 may be a light-emitting diode (Light-Emitting Diode, LED) light source. The LED light source includes a heat-conducting substrate. In one implementation, a plurality of reflectors can be arranged between multiple light-emitting chips, and the light from the gaps between multiple light-emitting chips can be reflected to the reflective light cup 150 through the reflectors, so as to improve the lighting efficiency of the light source 110 and save power consumption. Exemplarily, the reflective member may be a reflective film.

The above-mentioned embodiments of this application focus on the differences between the various embodiments. As long as the different optimization features of the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, here No longer.

The above descriptions are only examples of the present application, and are not intended to limit the present application. For those skilled in the art, various modifications and changes may occur in this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims (10)

1. A projector optical system, comprising: light source, first compensation element, second compensation element and curtain, wherein:

the first compensation element is arranged on the light emitting side of the light source and used for compensating the phase difference of emergent light of the light source in a first direction, wherein the first direction is the direction in which the emergent light of the light source penetrates through the first compensation element;

the second compensation element is arranged on the light emitting side of the first compensation element and used for compensating the phase difference of emergent light of the first compensation element in a second direction, wherein the second direction is a direction perpendicular to the first direction;

the emergent light of the second compensation element is projected to the curtain.

2. The projector optical system as set forth in claim 1 further comprising a reflective cup, a first lens, a reflective polarizer, a polarizer, and a display, wherein:

emergent light of the light source is diffused to the first lens through the reflecting light cup, the first lens is used for collimating the emergent light of the light source into multiple beams of parallel light, the multiple beams of parallel light sequentially penetrate through the first compensating element, the second compensating element and the reflecting type polarizing piece to reach the polarizer, the polarizer is used for decomposing the multiple beams of parallel light into P light and S light, the P light penetrates through the display to be projected to the curtain, the S light is reflected back to the second compensating element through the reflecting type polarizing piece, the S light penetrates through the second compensating element to be converted into right-handed circularly polarized light, the right-handed circularly polarized light sequentially penetrates through the first compensating element and the first lens to reach the reflecting light cup and is reflected and converted into left-handed circularly polarized light through the reflecting light cup, the left-handed circularly polarized light sequentially penetrates through the first lens and the first compensating element to reach the second compensating element, and the left-handed circularly polarized light penetrates through the second compensating element to be converted into the P light.

3. The projector optical system as defined in claim 2 wherein the first lens is a fresnel lens.

4. The projector optical system as recited in claim 3, further comprising a first anti-reflection component disposed on a flat surface of the Fresnel lens.

5. The projector optical system as defined in claim 1 further comprising a heat insulating glass disposed between the light source and the first compensation element.

6. The projector optical system as recited in claim 5, further comprising a second anti-reflection material disposed on a surface of the insulating glass.

7. The projector optical system as defined in claim 1 wherein the first compensation element is a C-plate.

8. The projector optical system as set forth in claim 1 wherein said second compensation element is a quarter wave plate.

9. The projector optical system as set forth in claim 1 wherein said quarter-wave plate is a wide-band quarter-wave plate.

10. The projector optical system as defined in claim 1 further comprising a reflector disposed in a gap between the light emitting chips of the light source.

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