JPH04106541A - Three-dimensional display device - Google Patents

Abstract

PURPOSE:To display an image, which has resolution corresponding to the performance of microlenses, in air by forming erect unmagnified images of a two-dimensional graphic on a screen surface at plane-symmetrical positions at all times through individual element lenses of a directional screen made of three lens array plates. CONSTITUTION:The distance bl1 between the intermediate lens array 12 of the directional screen DS, consisting of three lens array plates 11 - 13 provided in an optical path in series arrangement, and the front and rear array plates 11 and 13 is so determined that the erect unmagnified images of the two-dimensional graphic formed on a display surface through the individual element lenses of the directional screen DS consisting of the array plates are formed on the directional screen surfaces at the plane-symmetrical positions at all times. Then control is so performed by actuators 14 - 17 that the two-dimensional figure consisting of picture elements smaller than the diameter of many element lenses constituting the lens array plates is formed in air on the image plane of the two-dimensional graphic on the display surface of the two-dimensional graphic formed in air symmetrically with respect to the directional screen surface.

Description

[Detailed description of the invention]

[Industrial application field 1 The present invention relates to a three-dimensional display device.

[Prior Art] When the display portion of a two-dimensional figure is driven and displaced in a direction substantially perpendicular to the display surface of the two-dimensional figure, when it is displaced to different predetermined spatial positions, the display section corresponds to each spatial position. A three-dimensional display device in which a three-dimensional image is drawn in space by displaying a two-dimensional figure prepared in advance on the two-dimensional figure display section is, for example, X1iC.
T (X-ray computed tomography) display device. It is suitable as a three-dimensional image display device for many other uses, and various types of three-dimensional display devices have been proposed in the past. By the way, in the above-mentioned three-dimensional display device, a three-dimensional image is displayed in the air by moving the display section of the two-dimensional figure, which is the cross-sectional figure of the three-dimensional image, in space.
As a display section for two-dimensional figures, it is necessary to move within a movement range that is greater than the depth of the three-dimensional image, so if you want to display a large three-dimensional image, it is natural to use the display section for two-dimensional figures. The movement range of the 2-dimensional figure must also be increased, and therefore the acceleration applied to the two-dimensional figure display and other moving components becomes large, and if the limit is exceeded, the components may be destroyed. There are problems in that there is a limit to the size of the three-dimensional image that can be displayed, and a device with a sturdy structure is required if a large three-dimensional image is to be displayed. As disclosed in Japanese Patent Publication No. 63-52518 as a three-dimensional display device that does not suffer from the above-mentioned problems, the directions of incident light and transmitted light at each point on the screen are mirror-symmetrical with respect to the screen surface. A directional screen having the following properties is driven and displaced in the front and back direction with respect to its surface, and a plurality of two-dimensional objects corresponding to different predetermined positions occupying the space of the directional screen are By sequentially displaying the figures on a fixed surface near one side of the directional screen, the stroke of the moving component is half of the three-dimensional image to be displayed in the air. A three-dimensional display device, as illustrated in FIG. In FIG. 9, CRT is a cathode ray tube used as a display section for two-dimensional figures, and in this cathode ray tube CRT,
DS is a directional screen that displays two-dimensional figures representing cross-sections of a three-dimensional image to be displayed in the air one after another on a fluorescent screen by scanning an electron beam; It is configured to have a characteristic that it can emit incident light rays in a mirror-symmetrical manner, and is driven and displaced in the direction of arrow Y in the figure by a reciprocating linear motion drive device. In the three-dimensional display device shown in FIG. 9, one end of a slider 4 slidably supported by a sleeve 3 is connected to a crank 1 rotated by a motor M via a rod 2. Directional screen DS on the other end of 4
In addition, sleeve 5 is attached to the directional screen DS.
One end of a slider 6 that is slidably supported by the slider 6 is fixed, and the other end of the slider 6 is provided with a generator 7 for generating a position signal for the directional screen DS, so that the motor M described above is rotated. The directional screen DS is configured to perform reciprocating linear motion in the direction of the arrow Y in the figure, and
By displaying a two-dimensional figure required for each position in space on the fluorescent screen of the cathode ray tube CRT in accordance with the position signal generated from the position signal generator 7 of the directional screen DS, the cathode ray tube Due to the function of the directional screen DS, the two-dimensional figure on the fluorescent screen of the CRT forms a real image at a mirror-symmetrical position with respect to the screen surface, and three-dimensional images are formed in space.
Display dimensional image. That is, in FIG. 9, point A forms a real image at point A1, and point B forms a real image at point 81 on the phosphor screen of the cathode ray tube CRT, and the positions where the above real images are formed are on the directional screen DS and the cathode ray tube CRT. changes in response to the movement of. FIG. 12 is a diagram for specifically clarifying the above operation. In FIG. 12, pt indicates the position when the directional screen DS is closest to the fluorescent screen of the cathode ray tube CRT, and P2 indicates the position when the directional screen DS is most separated from the fluorescent screen of the cathode ray tube CRT. shows. Directional screen D when the directional screen DS is at position P1 when it is closest to the fluorescent screen of the cathode ray tube CRT
If the distance between S and the fluorescent screen of the cathode ray tube CRT is di, then the real image A generated in space by the directional screen DS is
', B' are cathode ray tube C in directional screen DS
The directional screen occupies a position dl at a distance from the directional screen DS on the side opposite to the RT side, and is at a position P2 when the directional screen DS is farthest away from the fluorescent screen of the cathode ray tube CRT. If the distance between DS and the fluorescent screen of the cathode ray tube CRT is dl, a real image As is generated in space by the directional screen DS. Since the distance between the directional screen DS and the fluorescent screen of the cathode ray tube CRT is dl, "B" is a real image A produced in space by the directional screen DS. occupies a position at a distance dl from the directional screen DS on the opposite side. The distance between the positions of the real images A' and B' is based on the position of the fluorescent screen of the cathode ray tube CRT. Also, the maximum amplitude S of the directional screen DS is 5=d2-di... (2) Since it is expressed by the above equation (2), the real image A'' in the figure. The position of B'' is at a distance of 28 points from the position of real images A' and B'.
The depth of the projection range IZ of the three-dimensional image that can be displayed at a distance is from the plane A'B' in Figure 1 to A jjB in Figure 1.
The three-dimensional image displayed in the air by the three-dimensional display device has a depth equivalent to twice the maximum amplitude S of the directional screen DS. [Problem to be Solved by the Invention] By the way, in the three-dimensional image display device described with reference to FIGS. 9 and 12, two-dimensional images corresponding to each cross section of the three-dimensional image are displayed in space. The directional screen DS used in For example, as illustrated in FIGS. 10 and 11, a lens array plate composed of a plurality of lens array plates arranged in series in the optical path has been used. The directional screen DS illustrated in FIG. 10 includes two lens array plates 4 on which a large number of convex lenses (element lenses) ε, ξ... each having the same focal length are arranged.
2.43 is arranged so that the optical axes and focal planes of the corresponding convex lenses in each of the lens array plates 42.43 coincide with each other, and the light diffusing surface 44 is disposed on the focal plane. In addition, the directional screen DS illustrated in FIG. 11 has convex lenses LL and L3 having the same focal lengths fl and f3, and a focal length f2 that is 1/2 of the focal length of the convex lenses L1 and L3 described above, i.e. , f
Lens arrays 8 and 10.9, each constructed using convex lenses L2 and the like with 2=fl/2=f3/2 as element lenses, are arranged in series as shown in FIG. It was structured in such a way that
The above-mentioned directional screen DS is an optical system having a function of allowing parallel light incident thereon to exit from the directional screen DS as parallel light, that is, a function of forming an image of an object at an infinite distance. It consisted of However, the objects handled by the directional screen DS are two-dimensional graphic boards Kl, K2, etc. placed at a finite distance from the directional screen DS, and the objects handled by the directional screen DS are the two-dimensional graphic boards Kl, K2... Real image position A'
, B'(A'',B'') are also generated at a finite distance from the directional screen DS, so the size of the pixel of the image emitted from the directional screen DS and formed in the air is directional. Since the diameter cannot be smaller than the diameter of the element lenses used in the lens arrays 8 to 10 constituting the digital screen DS, it has been difficult to display a high-resolution image in the air.

[Means for Solving the Problems] The present invention provides a two-dimensional image in which two-dimensional figures representing the cross-sectional figures are sequentially displayed in correspondence with each of a plurality of cross-sectional positions in a three-dimensional image to be displayed in the air. Relative displacement of the distance between the figure display surface and a directional screen that has a property that the directions of incident light and transmitted light at each point on the screen are mirror symmetrical with respect to the screen surface. In a three-dimensional display device that displays a three-dimensional image in the air, the above-mentioned directional screen includes three sets of lens array plates, each of which is constructed by two-dimensionally arranging minute element lenses. are arranged in series in the optical path, and in response to the change in the display surface of the two-dimensional figure, the finger, and the tiJ star screen interval, the orientation consisting of the three sets of lens array plates described above is used. The above-mentioned three sets of lens array plates are arranged so that an erect equal-magnification image of the above-mentioned two-dimensional figure display surface by each element lens in the directional screen is always formed at a position symmetrical with respect to the directional screen surface. a three-dimensional display device configured to control the interval between the three-dimensional images, and two-dimensional figures representing the cross-sectional figures individually corresponding to each of the plurality of cross-sectional positions in the three-dimensional image to be displayed in the air are sequentially displayed. The distance between the display surface of a two-dimensional figure and a directional screen that has a property that the directions of incident light and transmitted light at each point on the screen are mirror symmetrical with respect to the screen surface. In a three-dimensional display device that displays a three-dimensional image in the air by displacing the directional screen to In addition to using a configuration in which the lenses are arranged in series in the optical path, the lens array plate is made up of the two sets of lens array plates, corresponding to the change in the distance between the display surface of the two-dimensional figure and the directional screen. The three coarse lenses described above are arranged so that the erect equal-magnification image of the display surface of the two-dimensional figure formed by the element lenses in the directional screen is always formed at a position symmetrical to the surface of the directional screen. The spacing between array plates was controlled 3.
Provides a dimensional display device. [Operation] Three sets of lens array plates each consisting of a two-dimensional arrangement of minute element lenses are arranged in series in the optical path.
Distance between a directional screen configured such that the directions of incident light and transmitted light at each point on the screen exhibit mirror symmetry with respect to the screen surface, and the display surface of a two-dimensional figure In response to changes in The intervals between the three sets of lens array plates described above are controlled so that images are formed at plane-symmetrical positions. In addition, two sets of lens array plates, each consisting of a two-dimensional arrangement of minute element lenses, are arranged in series in the optical path, so that the direction of incident light and transmitted light at each point on the screen is adjusted. a directional screen configured to exhibit mirror symmetry with respect to the screen surface;
In response to changes in the distance between the dimensional figure and the display surface, the above 3.
In such a way that an erect equal-magnification image of the display surface of the two-dimensional figure formed by each element lens in a directional screen consisting of a set of lens array plates is always formed at a position symmetrical to the directional screen surface. The distance between the two sets of lens array plates described above is controlled. Thereby, it is possible to display in space an image having a resolution that corresponds to the performance of the microlenses used in the configuration of the lens array plate. [Embodiments] Hereinafter, specific details of the three-dimensional display device of the present invention will be explained in detail with reference to the accompanying drawings. FIG. 1 is a side sectional view showing the configuration of an embodiment of the three-dimensional display device of the present invention, and FIGS. 2 and 3 show the directivity used in the three-dimensional display device shown in FIG. FIG. 4 is a side sectional view used to explain the principle of construction and operation of the screen, and FIG. 4 is a diagram used to explain the directional screen used in the three-dimensional display device shown in FIG. 1. , FIGS. 5 to 8 are side sectional views showing other configurations of the directional screen. In Figure 1, a CRT is a cathode ray tube used as a display unit for two-dimensional figures, and in this cathode ray tube, two-dimensional figures corresponding to the cross section of a three-dimensional image to be displayed in the air are sequentially displayed by scanning an electron beam. It performs the operation of displaying on a fluorescent screen. The two-dimensional figure display unit described above may be of any configuration as long as it has the function of sequentially displaying two-dimensional figures corresponding to a plurality of cross sections of a three-dimensional image to be displayed in the air. Needless to say, it can be used. DS is a directional screen in which the direction of incident light and transmitted light at each point on the screen is mirror symmetrical with respect to the screen surface. Although the configuration is such that multiple sets of lens array plates each consisting of two-dimensionally arranged element lenses are arranged in series in the optical path, the specific configuration of this directional screen DS is Example is man 2
3, and 5 to 8, the directional screen DS is moved in the direction perpendicular to the screen surface by an arrow Y in FIG.
direction). The driving device for reciprocating linear movement of the directional screen DS used in the three-dimensional display device shown in FIG. 1 is used in the conventional three-dimensional display device already described with reference to FIG. One end of a slider 4, which is similar to the drive device for reciprocating linear motion of the directional screen DS, is slidably supported by a sleeve 3 via a rod 2 on a crank 1 rotated by a motor M. and a directional screen DS is fixed to the other end of the slider 4,
Furthermore, one end of a slider 6 that is slidably supported by the sleeve 5 is fixed to the directional screen DS, and a generator 7 for generating a position signal for the directional screen DS is provided at the other end of the slider 6. By rotating the aforementioned motor M, the directional screen DS is configured to perform reciprocating linear motion in the direction of the arrow Y in the figure. The position signal generator 7 of the above-mentioned directional screen DS may have any configuration from among optical position sensors, electrostatic position sensors, electrodynamic position sensors, electromagnetic position sensors, etc. Needless to say, it can be used. When the directional screen DS is displaced to different predetermined spatial positions, the two-dimensional figure display surface (cathode ray tube CRT) is By displaying the two-dimensional figures required for each position in space on the fluorescent screen, the two-dimensional figures on the fluorescent screen of the cathode ray tube CRT are displayed on the directional screen DS by the function of the directional screen DS. In order to display a three-dimensional image in space by forming a real image at a mirror-symmetrical position with respect to the central plane of the three-dimensional display device of the present invention, the cathode ray tube CR described above is used.
Change in the distance between the phosphor screen of T and a directional screen having a configuration in which multiple sets of lens array plates, each consisting of a two-dimensional arrangement of minute element lenses, are arranged in series in the optical path. Correspondingly, the erect equal-magnification image of the display surface of the two-dimensional figure formed by each element lens on the directional screen made up of the plurality of lens array plates is always plane-symmetrical with respect to the directional screen surface. The distance between the lens array plates in the directional screen is changed based on the position signal of the directional screen DS generated from the position signal generator 7 of the directional screen DS so that the image is formed at the position of , 2 of the display surface of the two-dimensional figure formed in the air with the center plane of the directional screen DS as the plane of symmetry.
The structure is such that a two-dimensional figure consisting of pixels smaller than the diameter of the many element lenses constituting the lens array plate is always formed in the air on the image plane of the dimensional figure. ', In the three-dimensional display device shown in the figure, the above-mentioned configuration generates a position signal (position signal in the form of an analog signal) of the directional screen DS generated from the position signal generator 7 of the directional screen DS. , is converted into a position signal in the form of a digital signal by the analog-to-digital converter 38, and the position signal in the form of a digital signal is used as an address signal to be sent from the conversion table 39 to the directional screen DS.
Then, the digital-to-analog converter 40 converts the signal output from the conversion table 39 into a displacement signal in the form of an analog signal, and converts the displacement signal in the form of the analog signal to the displacement signal in the form of an analog signal. is supplied to the drive device t41, and the drive device 41
By applying a drive signal to an actuator that displaces a plurality of lens array plates constituting a directional screen from The distance between the lens array plates in the directional screen consisting of a plurality of lens array plates arranged in series in the optical path is generated from the position signal generator 7 of the directional screen DS. It is adapted to be displaced based on the position signal of the directional screen DS. The directional screen DS used in the three-dimensional display device shown in FIG. A lens array plate 12 in which actuators 14, 15 and a large number of minute element lenses L2 (hereinafter, sometimes simply referred to as lenses L2) are arranged.
, the actuator 16, 17, and a lens array plate 13 in which a large number of minute element lenses L3 (hereinafter sometimes simply referred to as lenses L3) are arranged. The specific structure thereof is shown in FIGS. 2 and 3. The actuators 14 and 15 described above are cathode ray tube CRTs.
The two-dimensional figure displayed on the fluorescent screen of each lens L1 on the lens array plate 11 on the directional screen DS
As shown in FIG.
The driving bag described above is designed to perform an operation that changes according to the distance 11aQ1 between the phosphor screen and the directional screen DS! ! The actuators 16 and 17 are controlled by drive signals supplied from the cathode ray tube CR whose image is formed at the position of the principal plane of each lens L2 on the lens array plate 12 in the directional screen DS.
The two-dimensional figure on the fluorescent screen of T is the lens array plate 13
By each lens L3 in the directional screen DS
With the position of the principal plane of each lens L2 on the lens array plate 12 as the plane of symmetry, the lens array plates 11 to 13 A large number of minute element lenses L 1. The distance between the lens array plates 12 and 13 is set so that a two-dimensional figure consisting of pixels smaller than the diameter of L2 and L3 is formed.
The driving bag described above is designed to perform an operation of changing the distance aQi between the phosphor screen of the cathode ray tube CRT and the directional screen DS! ! It is controlled by a drive signal supplied from 41. 41st i! i is aQ1=a, bQ1=b, f==Lmm
1 is a diagram showing the relationship between a and b when In FIGS. 2 and 3, CRT is a cathode ray tube equipped with a fluorescent screen that serves as a display surface for two-dimensional figures, and this cathode ray tube CRT is similar to the cathode ray tube CRT shown in FIG.
It corresponds to Figure 2 shows the fluorescent screen and directional screen D of a cathode ray tube CRT.
Directional screen DS when the distance aQ1 from S is large
FIG. 3 is a diagram showing the states of three lens array plates 11 to 13 and actuators 14 to 17 in FIG.
It is a figure showing the state of three lens array plates 11-13 and actuators 14-17 in directional screen DS when distance aQ1 with is small. As described above, in the three-dimensional display device of the present invention, in response to changes in the distance aQ1 between the display surface of the two-dimensional figure (the fluorescent screen of the cathode ray tube CRT) and the directional screen, the arrangement mode is arranged in series in the optical path. Three sets of lens array plates 11~
The distance bQ1 between the intermediate lens array plate 12 and the front and rear lens array plates 11. The central plane of the directional screen DS is moved to a symmetrical plane by displacing the directional screen DS so that the erect equal-size image of the display surface of the two-dimensional figure always forms an image at a position symmetrical to the directional screen plane. A two-dimensional figure is always formed in the air on the image plane of the two-dimensional figure on the display surface of the two-dimensional figure formed in the air as It is clear that since the actuators 14 to 17 are controlled so that the state is such that the conventional interlayer point can be solved satisfactorily. As mentioned above, the actuator used to change the spacing between the plurality of lens array plates that make up the directional screen DS is piezoelectric (electrostrictive).
Type, electrodynamic type, electromagnetic type, and other arbitrary configurations can also be used. The action of the lenses L2 of the lens array plate 12 in the above-mentioned directional screen DS is such that even when the interval bQ1 between each lens array plate changes as described above, the light that has passed through the lens L1 of the lens array plate 11 is directed to the lens array. Board 13
This is to allow the light to enter the lens L3 effectively. That is, the distance bQ1 between the plurality of lens array plates 11 to 13 constituting the directional screen DS is such that the distance between the plurality of lens array plates of the directional screen DS described with reference to FIG. 11 is always kept constant. In this case, the directional screen DS can be configured such that the light that has passed through the optical axis of the lens Ll always passes through the optical axis of the lens L2 and the optical axis of the lens L3. In the dimensional display device, the distance between the plurality of lens array plates constituting the directional screen DS changes depending on the change in the distance a121 between the display surface of the two-dimensional figure (the fluorescent screen of the cathode ray tube CRT) and the directional screen DS. However, since the element lenses used in the plurality of lens array plates constituting the directional screen DS each have a constant focal length, When the distance between the plurality of lens array plates constituting the directional screen DS changes as described above, the light passing through the optical axis of the lens Ll is always aligned between the optical axis of the lens L2 and the lens L3. It is impossible to construct the directional screen DS in such a way that the optical axis passes through the lens array, and some vignetting is inevitable. It cannot be made incident on the lens L3 of the plate 13. Therefore, it is desirable to configure the directional screen DS in a state where the light utilization rate is as high as possible. Now, the focal length of the lens L1 of the lens array plate 11 is fl, and the focal length of the lens L2 of the lens array plate 12 is f2. The focal length of the lens L3 of the lens array plate 13 is f3, and in FIG. 4, a (= a Q 1) is 20 mm to 70 mm.
If it changes to 1mm, for example, the lens array plate 12
The focal length of the lens L2 corresponds to the change in the distance b21 between the lens array plates, that is, 8220 in FIG.
b = 1.053 corresponding to mm and a in Fig. 4
= approximately an intermediate value of b = 1.014 corresponding to 70 mm (the arithmetic mean value of 1.053 and 1.014 described above).
034) and 1.034fl=1°034f3=2f2 from the viewpoint of reducing vignetting caused by the lens. As in the case of the above example, the distance aQl=a between the directional screen DS and the display surface of the two-dimensional figure is 20 mm to 70 mm.
4, the change in the distance bλ1 between the lens array plates in the directional screen DS is very small, about 39 microns, so that the occurrence of vignetting due to the lenses can be ignored in practical terms. 5 and 6 show examples of the configuration of a directional screen DS constructed using a flat microlens array as three lens array plates, and 18 to 21 in each figure are glass substrates; In the figure, γ, γ, etc. are hemispherical refractive index distribution regions that have a lens effect formed on each of the flat glass substrates described above. It is well known that a lens array including a large number of distributed index lenses can be constructed by constructing a large number of hemispherical refractive index distribution regions having a gradient index by applying means such as an ion exchange method. 22, 23 shown in FIG. 5 and 28 shown in FIG. 6 are voids, and 24 to 27 shown in FIG. 5 and 28 shown in FIG. 29a
, 29b are actuators. Even if the directional screen DS configured as illustrated in FIGS. 5 and 6 described above is used in place of the directional screen DS shown in FIG. Similar to the three-dimensional display device shown, in response to changes in the distance between the two-dimensional figure display surface and the directional screen DS,
The erect equal-magnification image of the display surface of the above-mentioned two-dimensional figure by the individual element lenses γ, γ, etc. in the directional screen DS consisting of the plurality of lens array plates is always aligned with respect to the directional screen surface. An intermediate lens array plate and front and rear lens array plates in a directional screen DS consisting of three sets of lens array plates arranged in series in the optical path so that images are formed at plane-symmetrical positions. By changing the distance from The actuators 24 to 27 (shown in FIG. case), actuator 2
9a, 29b (in the case of FIG. 6), etc., to prevent the conventional gap from occurring. Next, FIGS. 7 and 81 show two sets of lens array plates 30 arranged in series in the optical path in response to changes in the distance between the two-dimensional figure display surface and the directional screen. 3
1 in the directional screen DS (in the case of FIG. 7) and two sets of lens array plates 34.3 arranged in series in the optical path.
The erect equal-magnification image of the display surface of the above-mentioned two-dimensional figure by the individual element lenses δ, δ... (in the case of FIG. 8) in the directional screen DS consisting of So that the image is formed at a plane-symmetrical position,
Arranged in series in the optical path! On the image plane of the two-dimensional figure of the display surface of the two-dimensional figure formed in the air with the center plane of the directional screen DS made up of two sets of lens array plates provided in the same manner as the plane of symmetry. A state in which a two-dimensional figure consisting of pixels smaller than the diameter of each element lens α, α, etc. of each of the many element lenses constituting the lens array plate 30, 31 is always formed in the air (in the case of Fig. 7). ), a state in which a two-dimensional figure consisting of pixels smaller than the diameter of each of the many element lenses δ, δ . Used in a three-dimensional display device configured to be controlled by actuators 32, 33 (in the case of Fig. 7) and actuators 36, 37 (in the case of Fig. 8), as in the case of Fig. 8). FIG. 2 is a diagram showing an example of the configuration of a directional screen DS. First, in the directional screen DS shown in FIG. 7, 30.31 and 32.3 are lens array plates, respectively.
3 is an actuator, and one lens array plate 30, 31 used in the configuration of the directional screen DS shown in FIG. This is a lens array plate constructed by applying the well-known so-called crystallized glass method. β and β· inside are the crystallized glass portions (light-shielding layers) after shrinkage. A concave lens-shaped space is formed in the portion where the spherical surfaces of each element lens α, α, etc. of the two lens array plates 32, 33 of the directional screen DS shown in FIG. 7 face each other. However, since each of the concave lens-shaped spaces described above can be considered to have an effect equivalent to a convex field lens, the directional screen DS shown in FIG. 7 has two lens array plates 32 and 33. . The lens array plate is composed of three lens array plates, including a large number of concave lens-shaped spaces formed in the spaces between the two lens array plates 32 and 33, and a lens array plate formed by field lenses of a large number of convex lenses. It can be considered that it has the same functions as the directional screen DS described above. Next, in the directional screen DS shown in FIG. 8, 34.35 and 36.3 are lens array plates, respectively.
7 is an actuator, and the configuration of the directional screen DS shown in FIG. It is constructed by arranging rod lenses δ, δ... that are configured to decrease.
Each rod lens δ, δ... used in the configuration of each lens array plate 34.35 described above is a 1/4 pitch lens, and the two lens array plates 34.35
Rod lenses δ, δ, . . . are configured as 72-pitch lenses (third quadrant lenses) that satisfy the 1:1 erect equal-magnification imaging condition. Even if the directional screen DS configured as illustrated in FIGS. 7 and 8 above is used in place of the directional screen DS shown in FIG. In response to the change in the distance between the display surface of the two-dimensional figure and the directional screen DS, as in the case of the three-dimensional display device,
The distance between the front and rear lens array plates in the directional screen DS, which is made up of two sets of lens array plates arranged in series in the optical path, is determined using the center plane in the thickness direction of the directional screen DS as a plane of symmetry. Formed into the air 2
On the image plane of the two-dimensional figure on the display surface of the dimensional figure, there are a large number of element lenses α, α, and
The lens array plate 3 is controlled by an actuator so that a two-dimensional figure consisting of pixels smaller than the diameter of
A large number of element lenses δ, δ... constitute 4, 35.
Conventional problems can be avoided by controlling the actuator so that a two-dimensional figure consisting of pixels smaller than the diameter of . Effects of the Invention 1 As is clear from the above detailed explanation, the three-dimensional display device of the present invention has three sets of lens array plates each consisting of a two-dimensional array of minute element lenses. A directional screen configured such that the directions of incident light and transmitted light at each point on the screen are mirror symmetrical with respect to the screen surface by arranging them in series in the optical path. , corresponding to the change in the distance from the display surface of the two-dimensional figure, an erect equal-magnification image of the display surface of the two-dimensional figure is created by each element lens in the directional screen consisting of the three sets of lens array plates. However, the spacing between the three sets of lens array plates described above is controlled so that the image is always formed at a plane-symmetrical position with respect to the directional screen surface, and minute element lenses are arranged two-dimensionally. Two sets of lens array plates are arranged in series in the optical path so that the direction of incident light and transmitted light at each point on the screen is mirror symmetrical with respect to the screen surface. In response to changes in the distance between the directional screen configured as a directional screen and the display surface of the two-dimensional figure, the above two-dimensional figure can be displayed by the individual element lenses in the directional screen consisting of the three sets of lens array plates. The distance between the two sets of lens array plates described above is controlled so that the erect equal-magnification image on the display surface is always formed in a plane-symmetrical position with respect to the directional screen surface. The three-dimensional display device of the invention can spatially display an image having a resolution corresponding to the performance of the microlenses used in the configuration of the lens array plate. In response to changes in the distance between the surface and the directional screen, the distance between the lens array plates in the directional screen DS, which is composed of multiple sets of lens array plates arranged in series in the optical path, is determined as the directional screen. On the image plane of a two-dimensional figure on the display surface of a two-dimensional figure formed in the air with the center plane in the thickness direction as the plane of symmetry in the DS, pixels smaller than the diameters of the many element lenses constituting the lens array plate are formed. More 2
Since dimensional figures are always formed in the air,
According to the present invention, the problems in the conventional three-dimensional display device described above can be satisfactorily solved.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the configuration of an embodiment of the three-dimensional display device of the present invention, and FIGS. 2 and 3 show the directivity used in the three-dimensional display device shown in FIG. FIG. 4 is a side sectional view used to explain the principle of construction and operation of the screen, and FIG. 4 is a diagram used to explain the directional screen used in the three-dimensional display device shown in FIG. 1. , and FIGS. 5 to 8 are diagrams for explaining directional screens having other configurations that have been used for indicating haze. CRT...Cathode ray tube, DS...Directional screen. M...Motor, Kl, K2...2D graphic board,
Ll-L3゜α~δ...Lens, 1...Crank,
2...Rod, 3゜5...Sleeve, 4.6...
Slider, 7...DS position signal generator, 8 to 10
~13.18~21°30.31,34,35...Lens array, 14~17.29a, 29b, 32,33
, 36.37...Actuator, 38...Analog-digital converter, 39...Conversion table, 40...
-Digital-analog converter, 41...drive device. = a (mm) Relationship with the case of the person making the amendment Patent Applicant Address 3-12 Moriya-cho, Kanayō-ku, Yokohama-shi, Kanagawa Prefecture Name (432) Victor Company of Japan Co., Ltd. 4, Agent 6, Details of the invention in the specification subject to amendment Explanation column 7, Correction details page 27, line 3 to page 30, line 12 "Figures 5 and 6 show a directional screen with three lenses..." The description is amended as follows. "Figure 5 shows an example of the configuration of a directional screen DS constructed using a flat microlens array as three lens array plates, 18 to 21 are glass substrates, and γ, γ... - is a hemispherical refractive index distribution region having a lens effect formed on each of the flat glass substrates described above; It is well known that a lens array comprising a large number of distributed index lenses can be constructed by constructing a gradient index region by applying means such as ion exchange, for example. .23 is a gap, and 24 to 27 are actuators.A directional screen DS having the configuration as illustrated in FIG. 5 is used instead of the directional screen DS shown in FIG. Even if it is used, the 2D display device shown in FIG.
In response to changes in the distance between the display surface of the dimensional figure and the directional screen DS, the individual element lenses γ, γ in the directional screen DS consisting of the plurality of lens array plates are adjusted.
A serial arrangement in the optical path so that the erect equal-magnification image of the display surface of the two-dimensional figure described above is always formed at a position symmetrical to the directional screen surface. By changing the distance between the middle lens array plate and the front and rear lens array plates in the directional screen DS consisting of three sets of lens array plates provided in the directional screen DS,
A large number of element lenses γ constituting the lens array plate are placed on the image plane of the two-dimensional figure on the display surface of the two-dimensional figure formed in the air with the center plane in the thickness direction of the intermediate lens array plate as the plane of symmetry. , γ... can be controlled by the actuators 24 to 27 so that a two-dimensional figure consisting of pixels smaller than the diameter of the pixels is always formed in the air, thereby avoiding the problems of the conventional method. can. Next, FIGS. 6 to 8 show two sets of lens array plates ( A set of lens array plates made up of two flat microlens arrays having glass substrates 18 and 19, and a pair of lens array plates made up of a flat microlens array having glass substrates 20 and 21. (in the case of Fig. 6), and two sets of lenses arranged in series in the optical path. Individual element lenses α in a directional screen DS consisting of lens array plates 30 and 31. α... (in the case of FIG. 7) and the individual element lenses δ, δ... (in the case of Fig. 8), so that the erect life-size image of the display surface of the two-dimensional figure described above is always imaged at a position symmetrical to the directional screen surface. A flat plate micrometer is placed on the image plane of the two-dimensional figure display plane formed in the air with the central plane of the directional screen DS made up of two sets of lens array plates arranged in a symmetrical manner. A shape M in which a two-dimensional figure consisting of pixels smaller than the diameter of each element lens γ, γ, etc. in the lens array is always formed in the air (in the case of FIG. 6), and the lens array plates 30, 31 are configured. A state in which a two-dimensional figure consisting of pixels smaller than the diameter of each element lens α, α, etc. of a large number of element lenses is always formed in the air (in the case of Fig. 7), the lens array plate 34, 35
The individual element lenses δ of the many element lenses that make up
, δ..., the actuators 29a, 29b (in the case of FIG. 6), the actuators 29a and 29b (in the case of FIG. 6), so that a two-dimensional figure consisting of pixels smaller than the diameter of . 32.33 (in the case of FIG. 7), an example of the configuration of a directional screen DS used in a three-dimensional display device configured to be controlled to change by an actuator 36.37 (in the case of FIG. 8) FIG. First, in the directional screen DS shown in FIG. 6, the flat microlens arrays used to construct the two sets of lens array plates are constructed on each of the flat glass substrates 18 to 21. A hemispherical refractive index distribution region γ having a lens effect. γ..., a gap 28 is provided between the two sets of lens array plates, and an actuator 29a
, 29b. In the directional screen DS configured as illustrated in FIG. 6, the directional screen composed of the plurality of lens array plates is The erect equal-magnification image of the display surface of the two-dimensional figure formed by the individual element lenses γ, γ, etc. on the directional screen DS is always formed at a position symmetrical to the directional screen surface. As shown in FIG. On the image plane of the two-dimensional figure on the display surface of the two-dimensional figure formed in the air as a surface, there is a two-dimensional image consisting of pixels smaller than the diameter of the many element lenses γ, γ, etc. that make up the lens array plate. The conventional problems can be avoided by controlling the actuators 29a and 29b so that the figure is always formed in the air.

Claims (1)

[Claims] 1. A two-dimensional figure display surface on which two-dimensional figures representing the above-mentioned cross-sectional figures are sequentially displayed in correspondence with each of a plurality of cross-sectional positions in a three-dimensional image to be displayed in the air. and a directional screen that has the property that the directions of incident light and transmitted light at each point on the screen are mirror symmetrical with respect to the screen surface, and In a three-dimensional display device that displays a three-dimensional image, three sets of lens array plates, each consisting of a two-dimensional arrangement of minute element lenses, are arranged in series in the optical path as the above-mentioned directional screen. In addition, in response to the change in the distance between the two-dimensional figure display surface and the directional screen, each of the directional screens made of the three sets of lens array plates is used. The spacing between the three sets of lens array plates is controlled so that an erect equal-magnification image of the display surface of the two-dimensional figure formed by the element lens is always formed at a position symmetrical to the directional screen surface. A three-dimensional display device 2 characterized in that two-dimensional figures representing the cross-sectional figures are sequentially displayed in correspondence with each of a plurality of cross-sectional positions in a three-dimensional image to be displayed in the air. The distance between the display surface of a two-dimensional figure and a directional screen that has a property that the directions of incident light and transmitted light at each point on the screen are mirror symmetrical with respect to the screen surface. In a three-dimensional display device that displays a three-dimensional image in the air by displacing the directional screen to In addition to using a configuration in which the lenses are arranged in series in the optical path, the lens array plate is made up of the two sets of lens array plates, corresponding to the change in the distance between the display surface of the two-dimensional figure and the directional screen. The above-mentioned three sets of lens arrays are arranged so that an erect equal-magnification image of the above-mentioned two-dimensional figure display surface by each element lens in the directional screen is always formed at a position symmetrical to the directional screen surface. A three-dimensional display device characterized by controlling the interval between plates.