JP2009020251A - Three-dimensional display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient three-dimensional display, providing a smooth control parallax. <P>SOLUTION: This three-dimensional display includes: optical systems S1, L1, L2, 4, Ls for generating a plurality of convergent light beams B1, B2 individually converted to a plurality of points P1, P2 separated from each other on the pupil of an observation eye 1; and a plurality of spatial light modulation elements 31, 32 for applying amplitude distribution equal to each of the plurality of light beams directed toward the plurality of points P1, P2 to the plurality of convergent light beams B1, B2, respectively, when a solid is disposed in front of the observation eye 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stereoscopic display.

  The binocular stereoscopic display displays an image with a parallax (parallax image) on both eyes of the observer. The observer can recognize a solid by observing different parallax images with each eye.

  However, since it is a light beam emitted from a planar parallax image that enters each eye, even if the observer tries to adjust the eye, the monocular cannot sense the depth of the solid (adjustment parallax). For this reason, the stereoscopic display position and the focus of the eye do not match, and the user feels uncomfortable.

In order to solve this problem, the binocular stereoscopic display described in Patent Document 1 displays parallax images side by side not only in the horizontal direction but also in the depth direction as viewed from the observer.
JP 2000-350237 A

  However, if a smooth adjustment parallax is to be obtained with this stereoscopic display, the number of parallax images to be arranged in the depth direction increases. If the number of parallax images is increased, it becomes difficult to save space and increase the definition of the display, which is inefficient.

  Accordingly, an object of the present invention is to provide an efficient stereoscopic display capable of obtaining a smooth adjustment parallax.

  The stereoscopic display according to the present invention includes an optical system that generates a plurality of condensed light beams that individually collect light at a plurality of points on the pupil of the observation eye, and the observation eye for each of the plurality of condensed light beams. And a spatial light modulator that provides an amplitude distribution equivalent to each of the plurality of light fluxes directed to the plurality of points when a solid is arranged in front of the light source.

  The optical system condenses a plurality of point light sources, an integrated optical system that superimposes a plurality of light beams emitted from the plurality of point light sources, and a plurality of light beams emitted from the integrated optical system on the plurality of points. And a condensing optical system.

  The spatial light modulator may be disposed at each of a plurality of optical paths between the plurality of point light sources and the integrated optical system.

  The spatial light modulation element is disposed at an optical path between the integrated optical system and the condensing optical system, and the plurality of point light sources and the spatial light modulation element include a plurality of different amplitude distributions. The condensed light beam may be generated by time division.

  The optical system includes a point light source, and a separation and condensing optical system that separates a light beam emitted from the point light source into a plurality of light beams superimposed on each other and condenses the plurality of light beams at the plurality of points. May be.

  The spatial light modulation element is disposed at an optical path between the separation and collection optical system and the point light source, and the spatial light modulation element and the separation and collection optical system include a plurality of different amplitude distributions. May be generated by space division.

  The separation and condensing optical system may be a microprism array.

  Further, the separation condensing optical system may be a micro mirror array.

  The arrangement direction of the plurality of points may be a left-right direction of the observer, and may further include diverging means for extending the condensing points of the plurality of condensed light beams in the up-down direction of the observer.

  In addition, any one of the three-dimensional displays passes the plurality of condensed light fluxes through corresponding light restricting units, and the above-described observation eye is arranged on the observation eye by a condensing optical system different from the plurality of condensing optical systems. A real image of the light limiting portion may be formed.

  Moreover, you may further provide the control means which makes the position of the condensing point of these several condensing light beams track the position of the said pupil.

  Further, the control means may have an optical deflection function in which the deflection direction is variable in order to change the positions of the condensing points of the plurality of condensed light beams.

  Further, the control means may use a camera capable of photographing the periphery of the observation eye in order to detect the position of the pupil.

  The control means projects a reference pattern via the optical system, and the light condensing is performed so that the positional relationship between the image of the reference pattern and the image of the pupil in the image acquired by the camera is maintained. You may control the position of the condensing point of a light beam.

  Further, the control means may change the modulation pattern of the spatial light modulation element according to the position of the pupil.

  According to the present invention, an efficient stereoscopic display capable of obtaining a smooth adjustment parallax is realized.

[Principle of Embodiment]
The principle of the three-dimensional display of this embodiment is demonstrated based on FIG.1, FIG.2, FIG.3.

  FIG. 1 is a diagram illustrating how the observation eye observes a solid. As shown in FIG. 1, the light beams BA, BB, BC,... Emitted from the points QA, QB, QC,. Each of the luminous fluxes BA, BB, BC,... Is individually collected near the retina of the observation eye 1 to form images QA ′, QB ′, QC ′,.

  Here, focusing on the two representative points QA and QB of the solid 2, since the points QA and QB are displaced in the front-rear direction, the formation positions of the images QA 'and QB' are also deviated in the front-rear direction. In this specification, each direction of the three-dimensional display is expressed as “vertical direction”, “horizontal direction”, “front-rear direction”, and the like depending on each direction viewed from the observer.

  Therefore, when the observation eye 1 performs adjustment (a lens thickness adjustment) to stare at the point QA, the image QA ′ is formed on the retina, but the image QB ′ is formed on a plane deviated from the retina. At this time, the image QA ′ looks sharp but the image QB ′ looks blurred to the observation eye 1.

  On the other hand, when the observation eye 1 performs adjustment (a lens thickness adjustment) in order to stare at the point QB, the image QB ′ is formed on the retina, but the image QA ′ is formed on a plane deviated from the retina. The At this time, the image QB ′ looks sharp to the observation eye 1, but the image QA ′ looks blurred.

  Therefore, a blur distribution is generated in the entire image QA ′, QB ′, QC ′,..., And the blur distribution changes when the observation eye 1 adjusts. Thereby, the observation eye 1 can feel the depth (adjustment parallax) of the solid 2. In addition, since the change in the blur distribution when the observation eye 1 performs adjustment is continuous, the adjustment parallax is smooth.

  FIG. 2 is a diagram illustrating a state in which a pinhole plate is disposed immediately before the pupil P of the observation eye. At this time, the single rays bA, bB, bC,... Emitted from the points QA, QB, QC,. In this case, each of the images QA ′, QB ′, QC ′... Is formed by a single light beam rather than a condensed light beam.

  Therefore, in this case, no blur distribution is generated in the entire images QA ′, QB ′, QC ′,..., And all the images QA ′, QB ′, QC ′,. Therefore, the observation eye 1 cannot feel the depth (adjustment parallax) of the solid 2.

  Based on the above, the following can be said.

  First, as shown in FIG. 3A, the observation eye 1 can feel the adjustment parallax when the whole area of the pupil P is open, but a pinhole plate is placed in front of the pupil P as shown in FIG. When placed, the observation eye 1 cannot feel the adjustment parallax.

  However, even if the pinhole plate is arranged, if the number of pinholes is made plural as shown in FIGS. 3B, 3C, and 3D, the images QA ′, QB ′, QC ′, .. Are formed by a plurality of light rays rather than a single light ray, so that a blur distribution is generated in the entire image QA ′, QB ′, QC ′,... To do. Therefore, the observation eye 1 can feel the adjustment parallax.

  Further, as shown in FIG. 3D, if the number of pinholes is small, the number of light rays representing each of the images QA ′, QB ′, QC ′,... Decreases, so that the images QA ′, QB ′, QC. Although the brightness of ',... Is lowered, the degree of blur distribution occurring in the entire image QA ′, QB ′, QC ′,. Since the amount of change in the distribution due to is sufficiently large, the adjusted parallax can be reliably obtained.

  Further, even if the number of light rays representing each of the images QA ′, QB ′, QC ′,... Is small, the blur distribution change accompanying the adjustment of the observation eye 1 becomes continuous, so that the adjustment parallax is smooth. Will not be damaged.

  Therefore, the stereoscopic display according to the present embodiment artificially creates the same situation as when the pinhole plate (the number of pinholes is 2) shown in FIG. 3D is arranged in front of the pupil P of the observation eye 1. It was supposed to be.

  That is, the stereoscopic display according to the present embodiment includes a light beam B1 that is focused on a point at one end of the pupil of the observation eye 1 as shown in FIG. 4A and a pupil of the observation eye 1 as shown in FIG. Is generated at the other end of the beam, and an amplitude distribution equivalent to that of the light beam from the solid 2 toward the light condensing point P1 of the light beam B1 is given to the light beam B1. An amplitude distribution equivalent to the light beam from 2 toward the condensing point P2 of the light beam B2 is given. This gives a smooth adjustment parallax to the observation eye 1.

  Further, since there is no degree of freedom in the position of the observation eye 1 with only this, the stereoscopic display of the present embodiment causes the positions of the condensing points P1 and P2 to follow the position of the pupil of the observation eye 1 and accordingly the light beam B1. , B2 is time-modulated. Thereby, motion parallax is given to the observation eye 1.

[First Embodiment]
A first embodiment of a three-dimensional display will be described with reference to FIGS. 5, 6, and 7. FIG.

  The three-dimensional display has a right eye system that faces the viewer's right eye and a left eye system that faces the viewer's left eye, but the configuration of both is the same (symmetrical). The eye system will be described.

  FIG. 5 is a diagram showing the right eye system of the present embodiment. As shown in FIG. 5, the right eye system includes two point light sources S1, S2, two lenses L1, L2, two transmissive spatial light modulators 31, 32, one half mirror 4, and one And a lens Ls.

  The light beam B1 emitted from the point light source S1 is converted into a parallel light beam by the lens L1. The light beam B1 that has become a parallel light beam passes through the transmissive spatial light modulator 31 and is amplitude-modulated in the spatial direction. The light beam B1 after amplitude modulation passes through the half mirror 4 and is then collected by the lens Ls. Hereinafter, the condensing point of the light beam B1 is referred to as a “condensing point P1”.

  The light beam B2 emitted from the point light source S2 is converted into a parallel light beam by the lens L2. The light beam B <b> 2 that has become a parallel light beam passes through the transmissive spatial light modulator 32 and is amplitude-modulated in the spatial direction. The light beam B2 after amplitude modulation is reflected by the half mirror 4 and then condensed by the lens Ls. Hereinafter, the condensing point of the light beam B2 is referred to as a “condensing point P2”.

  That is, the two light beams B1 and B2 individually emitted from the point light sources S1 and S2 are superimposed in front of the observation eye 1 by the half mirror 4.

  However, the optical axis of the optical system from the point light source S1 to the transmissive spatial light modulator 31 is tilted to the left of the optical axis of the lens Ls, and the optical from the point light source S2 to the transmissive spatial light modulator 32 is optical. The optical axis of the system is inclined at an equal angle to the right side of the optical axis of the lens Ls. Due to this inclination, the condensing points P1 and P2 are shifted in the left-right direction.

  The amount of deviation between the condensing points P1 and P2 is set to be slightly smaller than the pupil diameter of the observation eye 1. Since the pupil diameter of the observation eye 1 is about 7 mm in the dark place and about 2 mm in the bright place, when the emission intensity of the point light sources S1 and S2 is weak, the deviation amount of the condensing points P1 and P2 should be set to be less than 7 mm. When the light emission intensity of the point light sources S1 and S2 is strong, the amount of deviation between the condensing points P1 and P2 can be set to less than 2 mm. Thereby, the condensing point P1 is located at the right end of the pupil of the observation eye 1, and the condensing point P2 is located at the left end of the pupil of the observation eye 1.

  The transmissive spatial light modulators 31 and 32 are elements that can modulate the amplitude of the incident light beam spatially and temporally. The modulation pattern is controlled by an electric circuit (not shown). A two-dimensional transmissive liquid crystal display panel can be applied to the transmissive spatial light modulation elements 31 and 32. However, if the transmissive spatial light modulation elements 31 and 32 in the stereoscopic display diffuse light, a problem occurs. Therefore, when a transmissive liquid crystal display panel is applied, the diffusion plate provided in the liquid crystal display panel is removed. And

  Each modulation pattern (transmittance distribution) of each of the transmissive spatial light modulation elements 31 and 32 is set so that a solid is visually recognized in front of the observation eye 1. That is, the modulation pattern (transmittance distribution) of the transmissive spatial light modulator 31 is set to be the same as the amplitude distribution of the light beam from the solid toward the point P1, and the modulation pattern (transmittance distribution) of the transmissive spatial light modulator 32 is set. ) Is set to be the same as the amplitude distribution of the light beam from the solid toward the point P2. Thereby, the adjustment parallax is given to the observation eye 1.

  Furthermore, the right eye system described above is provided with a tracking mechanism (not shown) that causes the positions of the condensing points P1 and P2 to follow the position of the pupil of the observation eye 1. The tracking mechanism basically includes a Z tracking mechanism that displaces the condensing points P1 and P2 in the front-rear direction and an XY tracking mechanism that displaces the condensing points P1 and P2 in the vertical and horizontal directions. Regardless of the position of the eye 1, it functions to maintain the positional relationship between the condensing points P1 and P2 and the pupil.

  FIG. 6 is a diagram for explaining the operation of the Z following mechanism of the present embodiment.

  As shown in FIG. 6, when the observation eye 1 is displaced in the front-rear direction Aa, the Z tracking mechanism individually displaces the point light sources S1, S2 in the optical axis directions Aa'1, Aa'2. Thereby, the condensing points P1 and P2 are displaced in the front-rear direction.

  FIG. 7 is a diagram for explaining the operation of the XY tracking mechanism of the present embodiment.

  As shown in FIG. 7, when the observation eye 1 is displaced in the left-right direction Ah, the XY tracking mechanism causes the entire elements (from the point light sources S1, S2 to the half mirror 4) within the dotted line frame to be near the center of the lens Ls. And turn around a straight line extending in the vertical direction (direction Ah ′). Thereby, the condensing points P1 and P2 are displaced in the left-right direction.

  When the observation eye 1 is displaced in the vertical direction Av, the XY tracking mechanism moves the entire element (from the point light sources S1, S2 to the half mirror 4) in the dotted frame in the horizontal direction through the vicinity of the center of the lens Ls. It is rotated around the extending straight line (direction Av ′). Thereby, the condensing points P1 and P2 are displaced in the vertical direction.

  The transmissive spatial light modulation elements 31 and 32 change the modulation pattern according to the position of the pupil so that motion parallax is given to the observation eye 1 when the position of the pupil of the observation eye 1 changes.

  In addition, the configuration of the left eye system is the same as the configuration of the right eye system described above (symmetric), but the left-eye transmission spatial light modulation element and the right-eye transmission spatial light modulation element are: In order to give binocular parallax to the observation eye 1, a difference is provided between the two modulation patterns.

  In the Z follow-up mechanism (FIG. 6) of the present embodiment, the point light sources S1 and S2 are displaced in the optical axis direction, but the entire right eye system may be displaced in the front-rear direction. Moreover, although the XY tracking mechanism (FIG. 7) of this embodiment rotated the element in a dotted-line frame, you may displace the whole right eye system to an up-down and left-right direction.

[Second Embodiment]
A second embodiment of the stereoscopic display will be described with reference to FIG.

  This embodiment is a modification of the first embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, differences from the first embodiment of the right eye system of this embodiment will be described here.

  FIG. 8 is a diagram showing the right eye system of the present embodiment. As shown in FIG. 8, in the right eye system of the present embodiment, two light beams B1 and B2 are superimposed in front of the transmissive spatial light modulation element 31, and the transmissive spatial light modulation element 31 is combined with the two light beams B1, B1. Also used for B2.

  The light beam B1 emitted from the point light source S1 is converted into a parallel light beam via the lens L1 ', the reflecting mirror 6, and the lens Ls'. The light beam B1 that has become a parallel light beam passes through the transmissive spatial light modulator 31 and is amplitude-modulated in the spatial direction. The light beam B1 after amplitude modulation is condensed by the lens Ls.

  The light beam B2 emitted from the point light source S2 is converted into a parallel light beam through the lens L2 ', the reflecting mirror 6, and the lens Ls'. The light beam B2 that has become a parallel light beam passes through the transmissive spatial light modulator 31 and is amplitude-modulated in the spatial direction. The light beam B2 after amplitude modulation is condensed by the lens Ls.

  That is, the two light beams B1 and B2 individually emitted from the point light sources S1 and S2 are superimposed by the reflecting mirror 6 before the lens Ls ′.

  However, the optical axis of the optical system composed of the point light source S1 and the lens L1 ′ is tilted to the left of the optical axis of the lens Ls ′, and the optical axis of the optical system composed of the point light source S2 and the lens L2 ′ is the lens. It is inclined at an equal angle to the right side of the optical axis of Ls ′. Due to this inclination, the condensing point P1 of the light beam B1 and the condensing point P2 of the light beam B2 are shifted in the left-right direction. The positional relationship between these condensing points P1 and P2 and the pupil of the observation eye 1 is the same as that in the first embodiment.

  Therefore, in the present embodiment, the number of spatial light modulation elements can be suppressed, but the same effect as in the first embodiment can be obtained.

  In the present embodiment, since one transmissive spatial light modulator 31 is also used for the light beams B1 and B2, different amplitude distributions cannot be simultaneously applied to the light beams B1 and B2.

  For this reason, the electric circuit of the present embodiment switches the light fluxes B1 and B2 having different amplitude distributions in a time-sharing manner by switching the modulation pattern of the transmissive spatial light modulator 31 while turning on the point light sources S1 and S2 alternately. Need to be generated.

[Third Embodiment]
A third embodiment of the three-dimensional display will be described with reference to FIGS. 9, 10, 11, and 12.

  This embodiment is a modification of the first embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, differences from the first embodiment of the right eye system of this embodiment will be described here.

  FIG. 9 is a diagram showing the right eye system of the present embodiment. FIG. 9 also shows the left eye system as well as the right eye system. As shown in FIG. 9, in the right-eye system of the present embodiment, two condensing points P1 and P2 are one point light source S1, one lens L1, one transmissive spatial light modulator 31, and 1 And two microprism arrays 9. The arrangement destination of the microprism array 9 is a position close to the emission side of the transmissive spatial light modulator 31.

  The light beam B emitted from the point light source S1 is converted into a parallel light beam by the lens L1. The light beam B that has become a parallel light beam passes through the transmissive spatial light modulator 31 and is amplitude-modulated in the spatial direction. The amplitude-modulated light beam B is separated by the microprism array 9 into two light beams B1 and B2 that are condensed at different points P1 and P2. The positional relationship between the condensing point P1 of the light beam B1, the condensing point P2 of the light beam B2, and the pupil of the observation eye 1 is the same as that of the first embodiment.

  FIG. 10 is an enlarged view in a dotted circle in FIG. However, in FIG. 10, the distance between the microprism array 9 and the focal points P1 and P2 is drawn closer to that of FIG. As shown in FIG. 10, the shape of each microprism MP constituting the microprism array 9 is adjusted in advance so as to deflect the incident light beam toward the observation eye 1.

  However, one of the two microprisms MP adjacent in the left-right direction deflects incident light toward the point P1, while the other deflects incident light toward the point P2.

  That is, as shown in FIG. 11, in the left-right direction of the microprism array 9, the microprism MP1 for generating the light beam B1 and the microprism MP2 for generating the light beam B2 are alternately arranged. Thereby, the microprism array 9 is provided with a function of separating the light beam B into two light beams and a function of condensing each of the separated two light beams.

  The modulation pattern of the transmissive spatial light modulation element 31 is given the same amplitude distribution as the light beam from the solid to the point P1 for the light beam B1, and the same as the light beam from the solid to the point P2 for the light beam B2. It is set so that an amplitude distribution is given. As a result, the transmissive spatial light modulator 31 and the microprism array 9 generate light beams B1 and B2 having different amplitude distributions by space division.

  Therefore, in this embodiment, the number of spatial light modulation elements and the number of other optical elements can be suppressed, but the same effect as that of the first embodiment can be obtained. Since such a three-dimensional display can be reduced in size and weight, it is suitable for a head-mounted type three-dimensional display, for example.

  In the microprism array 9 of the present embodiment, the microprisms MP1 and MP2 are alternately arranged in the left-right direction as shown in FIG. 11, but may be alternately arranged in the up-down direction as shown in FIG. Good. Alternatively, the microprisms MP1 and MP2 may be alternately arranged in both the left-right direction and the up-down direction.

  Further, the follow-up mechanism of the present embodiment can displace the condensing points P1 and P2 in the front-rear direction, the up-down direction, and the left-right direction only by moving the point light source S1 in the front-rear direction, the up-down direction, and the left-right direction.

  In the present embodiment, the left eye system and the right eye system are prepared separately. However, the microprism array 9 has a function of separating the light beam B into four light beams and condenses each of the light beams. If the function is added, the right eye system and the left eye system can be integrated.

[Fourth Embodiment]
A fourth embodiment of a three-dimensional display will be described with reference to FIGS.

  This embodiment is a modification of the third embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, here, differences from the third embodiment (FIG. 9) of the right eye system of this embodiment will be described.

  FIG. 13 is a diagram showing the right eye system of the present embodiment. As shown in FIG. 13, the right-eye system of this embodiment includes a micromirror array MA instead of the microprism array 9, a light source unit Sf instead of the point light source S1, and a light guide plate instead of the lens L1. 10 is provided. The micromirror array MA is disposed behind the transmissive spatial light modulator 31, and the light guide plate 10 is disposed in front of the transmissive spatial light modulator 31.

  The light source unit Sf converts the light beam emitted from the point light source into a parallel light beam having a slit-like cross section (sheet-like parallel light beam). The light beam Bf emitted from the light source unit Sf enters the light guide plate 10 from its side surface.

  FIG. 14 is a partially enlarged view of FIG. As shown in FIG. 14, a plurality of micro beam splitters BS are arranged inside the light guide plate 10. Each microbeam splitter BS forms an angle of 45 ° with respect to the light beam Bf. For such a light guide plate 10, for example, SBG (Switchable Bragg Grating) using Bragg reflection as disclosed in US Pat. No. 6,894,814 can be used.

  The light beam Bf incident on the light guide plate 10 is gradually reflected in the direction of the transmissive spatial light modulator 31 by the plurality of microbeam splitters BS, and converted into a parallel light beam incident on the entire transmissive spatial light modulator 31. The The parallel light flux is amplitude-modulated in the spatial direction in the transmissive spatial light modulator 31 and then enters the entire micromirror array MA.

  The postures of the individual micromirrors MM of the micromirror array MA are adjusted so as to deflect the incident light beam toward the observation eye 1. However, one of the two micromirrors MM adjacent in the left-right direction deflects incident light toward the point P1, while the other deflects incident light toward the point P2.

  That is, in the left-right direction of the micromirror array MA, micromirrors for generating the light beam B1 and micromirrors for generating the light beam B2 are alternately arranged. Thereby, the micromirror array MA is provided with a function of separating the incident light beam into two light beams and a function of condensing each of the separated two light beams.

  Therefore, in this embodiment, a micromirror array is used instead of the microprism array, but the same effect as in the third embodiment can be obtained.

  In the micromirror array MA of the present embodiment, the micromirrors for generating the light beam B1 and the micromirrors for generating the light beam B2 are alternately arranged in the left-right direction. You may arrange | position alternately. Or you may arrange | position those micromirrors alternately in both the left-right direction and an up-down direction.

  In addition, when a micromirror array having a variable micromirror orientation distribution is used as the micromirror array MA of the present embodiment, the micromirror array MA itself can freely change the position of the condensing point. The two light beams B1 and B2 may be generated by time division.

  In addition, when a micromirror array having a variable micromirror orientation distribution is used as the micromirror array MA of the present embodiment, the micromirror array MA itself can freely change the position of the condensing point. The function of the tracking mechanism may be given to the micromirror array MA, and the tracking mechanism may be omitted instead.

  In the present embodiment, the right eye system and the left eye system are prepared separately. However, if the function of generating four light beams by space division or time division is added to one micromirror array MA, the right eye system is provided. The system and the left eye system can also be integrated.

[Fifth Embodiment]
A fifth embodiment of a stereoscopic display will be described with reference to FIG.

  This embodiment is a modification of the fourth embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, here, differences from the fourth embodiment of the right eye system of this embodiment will be described.

  FIG. 15 is a diagram illustrating the right eye system of the present embodiment. As shown in FIG. 15, in the right eye system of the present embodiment, a deflector array 5A is provided instead of the micromirror array MA. The deflector array 5 </ b> A is disposed in front of the transmissive spatial light modulator 31, and the light guide plate 10 is disposed behind the transmissive spatial light modulator 31.

  The individual deflectors constituting the deflector array 5A change the traveling direction of incident light, and the amount of change is controlled by an electric circuit (not shown). For example, a refractive index distribution type optical deflector as disclosed in JP-A-7-64123 is applicable to each polarizer.

  The light beam Bf emitted from the light source unit Sf enters the side surface of the light guide plate 10. The light beam Bf incident on the light guide plate 10 is gradually reflected in the direction of the transmissive spatial light modulator 31 and converted into a parallel light beam incident on the entire transmissive spatial light modulator 31. The parallel light beam is amplitude-modulated in the spatial direction by the transmissive spatial light modulator 31 and then enters the entire deflector array 5A and is separated into two light beams B1 and B2 that are condensed at different points P1 and P2. Is done.

  In the left-right direction of the deflector array 5A, deflectors for generating the light beam B1 and deflectors for generating the light beam B2 are alternately arranged. Thereby, the deflector array 5A is provided with a function of separating the light beam into two light beams and a function of individually condensing the separated two light beams.

  Therefore, in this embodiment, a polarizer array is used instead of the micromirror array, but the same effect as in the fourth embodiment can be obtained.

  In the deflector array 5A of the present embodiment, the deflector for generating the light beam B1 and the deflector for generating the light beam M2 are alternately arranged in the left-right direction, but alternately in the vertical direction. You may arrange in. Or you may arrange | position those deflectors alternately over both the left-right direction and the up-down direction.

  Moreover, since the deflector array 5A of this embodiment can change the position of a condensing point freely, you may produce | generate two light beams B1 and B2 by a time division.

  Further, since the deflector array 5A of the present embodiment can freely change the position of the condensing point, the function of the tracking mechanism can be given to the deflector array 5A, and the tracking mechanism can be omitted instead. Good.

  In the present embodiment, the right eye system and the left eye system are prepared separately. However, if the function of generating four light beams by space division or time division is added to one deflector array 5A, the right eye system is provided. The system and the left eye system can also be integrated.

[Sixth Embodiment]
A sixth embodiment of the stereoscopic display will be described with reference to FIG.

  This embodiment is a modification of the first embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, differences from the first embodiment of the right eye system of this embodiment will be described here.

  FIG. 16 is a diagram showing the right eye system of the present embodiment. As shown in FIG. 16, a deflector 5 is added to the right eye system of the present embodiment. The placement destination of the deflector 5 is a position close to the lens Ls on the emission side of the lens Ls. The deflector 5 changes the traveling direction of the light beams B1 and B2, and the amount of change is controlled by an electric circuit (not shown). Thereby, the condensing points P1 and P2 can be displaced vertically and horizontally. Therefore, in this embodiment, the XY tracking mechanism can be omitted.

  Examples of such a deflector 5 include a refractive index distribution type optical deflector as disclosed in JP-A-7-64123 and liquid crystal light as disclosed in JP-A-2005-352257. A beam deflector or the like is applicable.

  When a liquid crystal light beam deflector is used as the deflector 5, not only the traveling direction of the light beams B1 and B2 but also the curvature of the wavefront can be changed. That is, the condensing points P1 and P2 can be displaced not only in the vertical and horizontal directions but also in the longitudinal direction. Therefore, when a liquid crystal light beam deflector is used as the deflector 5, both the XY tracking mechanism and the Z tracking mechanism can be omitted.

  Although this embodiment is a modification of the first embodiment, any of the second to third embodiments may be similarly modified. Incidentally, since the deflector array 5A of the fifth embodiment can freely change the position of the condensing point, it does not need to be deformed in this way. Further, when the attitude distribution of the micromirrors of the micromirror array MA of the fourth embodiment is variable, the position of the condensing point can be freely changed, and thus there is no need for such deformation.

[Seventh Embodiment]
A seventh embodiment of a stereoscopic display will be described with reference to FIG.

  This embodiment is a modification of the sixth embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, here, differences from the sixth embodiment of the left eye system of this embodiment will be described.

  FIG. 17 is a diagram illustrating the left eye system of the present embodiment. As shown in FIG. 17, a deflection optical system 5G is arranged instead of the deflector 5 in the left eye system of the present embodiment. The arrangement destination of the deflection optical system 5G is between the condensing points P1 and P2 and the observation eye 1.

  The deflecting optical system 5G includes two lenses Ls1 and Ls2 constituting a relay lens, and a variable angle plane mirror M disposed between the two lenses Ls1 and Ls2.

  The light beam B1 emitted from the condensing point P1 forms a condensing point P1 'on the pupil of the observation eye 1 via the lens Ls1, the plane mirror M, and the lens Ls2. The light beam B2 emitted from the condensing point P2 forms a condensing point P2 'on the pupil of the observation eye 1 via the lens Ls1, the plane mirror M, and the lens Ls2. The positional relationship between the condensing points P1 'and P2' and the pupil is the same as the positional relationship between the condensing points P1 and P2 and the pupil in the first embodiment.

  The plane mirror M is rotatable around a straight line extending in the vertical direction through the vicinity of the center of the reflecting surface (direction Ah ′). The rotation angle of the plane mirror M is controlled by an electric circuit (not shown). As a result, the condensing points P1 'and P2' are displaced in the left-right direction while maintaining the positional relationship between them.

  When the focal point is displaced in the vertical and horizontal directions, two sets of deflection optical systems are arranged by arranging two sets of relay lenses in series and individually arranging two plane mirrors on each of the relay lenses. One of these deflection optical systems may have a function of displacing the condensing point in the left-right direction, and the other may have a function of displacing the condensing point in the up-down direction.

[Eighth Embodiment]
An eighth embodiment of a three-dimensional display will be described with reference to FIGS.

  This embodiment is a modification of the first embodiment. Also in this embodiment, the right eye system and the left eye system are the same. Therefore, differences from the first embodiment of the right eye system of this embodiment will be described here.

  18 is a diagram showing the right eye system of the present embodiment (viewed from above the observation eye 1), and FIG. 19 is a diagram of the right eye system viewed from the left (however, FIG. 19). (The half mirror 4 is represented by a dotted line.)

  As shown in FIGS. 18 and 19, in the right eye system of the present embodiment, a cylindrical lens Lc is arranged instead of the lens Ls, and the one-dimensional diffusion plate 7 is arranged at a position close to the exit side of the cylindrical lens Lc. Is done. The generatrix direction of the cylindrical lens Lc is the vertical direction, and the diffusion direction of the one-dimensional diffusion plate 7 is also the vertical direction. In this case, as shown in FIG. 20, the condensing points P1 and P2 of the light beams B1 and B2 are extended in the vertical direction. Therefore, in this embodiment, even if the pupil of the observation eye 1 is displaced in the vertical direction, it is not necessary to displace the condensing points P1 and P2 in the vertical direction.

  However, the transmissive spatial light modulation elements 31 and 32 need to change the modulation pattern so that motion parallax is given to the observation eye 1 when the pupil of the observation eye 1 moves in the vertical direction.

  In addition, although this embodiment is a modification of 1st Embodiment, you may deform | transform 2nd Embodiment similarly.

[Ninth Embodiment]
A ninth embodiment of a three-dimensional display will be described with reference to FIGS.

  This embodiment is a modification of the fourth embodiment (FIG. 13). Also in this embodiment, the right eye system and the left eye system are the same. Therefore, here, differences from the fourth embodiment of the right eye system of this embodiment will be described.

  FIG. 21 is a diagram showing the right eye system of the present embodiment (viewed from above the observation eye 1), and FIG. 22 is a diagram of the right eye system viewed from the left.

  As shown in FIGS. 21 and 22, the one-dimensional diffusion plate 7 is disposed on the observation eye side of the light guide plate 10 in the right eye system of the present embodiment. The diffusion direction of the one-dimensional diffusion plate 7 is the vertical direction. And it is not necessary to give the up-and-down condensing function to micromirror array MA.

  Also in this case, as shown in FIG. 20, the same effect as that obtained by extending each of the condensing points P1 and P2 in the vertical direction can be obtained. Therefore, even in this embodiment, even if the pupil of the observation eye 1 is displaced in the vertical direction, it is not necessary to displace the condensing points P1 and P2 in the vertical direction.

  However, the transmissive spatial light modulator 31 needs to change the modulation pattern so that motion parallax is given to the observation eye 1 when the pupil of the observation eye 1 moves in the vertical direction.

  In addition, although this embodiment is a modification of 4th Embodiment, you may deform | transform similarly 3rd Embodiment or 5th Embodiment.

[Effect of each embodiment]
The three-dimensional display of each embodiment described above generates only several types of light beams (here, two light beams per observation eye) in order to display a solid. In addition, these light fluxes are necessary for obtaining smoothness of the adjustment parallax.

  On the other hand, the stereoscopic display of each embodiment uses a tracking mechanism and an optical element in combination instead of increasing the number of spatial light modulation elements in order to give motion parallax to the observation eye 1.

  Therefore, in the stereoscopic display of this embodiment, although both the adjustment parallax and the motion parallax can be obtained, the number of spatial light modulation elements can be suppressed to a small number (at least four per observer). Further, since all the light beams modulated by the spatial light modulation element are guided to the pupil of the observation eye, no unnecessary light beams are generated. Therefore, the size, manufacturing cost, and energy consumption during use of the 3D display can all be kept low.

[Ninth Embodiment]
A ninth embodiment of a stereoscopic display will be described with reference to FIG.

  The present embodiment is a modification of the first embodiment, and also in the present embodiment, the right eye system and the left eye system are the same. Therefore, differences from the first embodiment of the right eye system of this embodiment will be described here.

  FIG. 25 is a diagram showing the right eye system of the present embodiment. As shown in FIG. 25, in the right eye system of the present embodiment, the light beam B1 collected by the lens Ls is passed through the pinhole Ph1, and is further condensed by the lens Lr at the condensing point P1. Similarly, the light beam B2 collected by the lens Ls is passed through the pinhole Ph2 and condensed at the condensing point P2 by the lens Lr.

  In the present embodiment, when the light beams B1 and B2 are passed through the pinhole Ph1 and the pinhole Ph2, respectively, the point light sources S1 and S2 are spread, or the light beams B1 and B2 are transmissive spatial light modulation. Even when diffraction spread is caused by passing through the elements 31 and 32, the light beams B1 and B2 can be accurately collected with respect to the condensing points P1 and P2.

[Embodiment of detection system]
Although not described in each of the above embodiments, the three-dimensional display of each embodiment includes a detection system that detects a deviation between the pupil of the observation eye 1 and the condensing points P1 and P2.

  Therefore, here, the detection system applied to the right eye system of the first embodiment will be described as a representative.

  FIG. 23 is a diagram of the right eye system of the first embodiment viewed from the left (however, in FIG. 23, the half mirror 4 is represented by a dotted line). As shown in FIG. 23, the detection system includes a camera 8 that captures the observation eye 1 and its peripheral part, and a detection light source Sm. Although not shown, the detection system includes a signal generation circuit.

  The camera 8 is fixed and has a field of view that is wide enough to capture the observation eye 1 and its periphery. The detection light source Sm is arranged at a position away from the point light source S1 by a predetermined distance, and emits detection light Bm. The light Bm forms a beam spot Bs through the lens L1, the transmissive spatial light modulator 31, the half mirror 4, and the lens Ls. Since the detection light source Sm and the point light source S1 are separated from each other, the beam spot Bs is formed at a position away from the condensing points P1 and P2.

  Here, the detection light source Sm of the detection system is fixed with respect to the point light source S1 of the right eye system. Therefore, the positional relationship between the condensing points P1 and P2 generated by the right eye system and the beam spot Bs generated by the detection system is also fixed.

  FIG. 24 is a diagram illustrating an image captured by the camera 8. As shown in FIG. 24, the periphery of the observation eye 1 is shown in this image. An image captured by the camera 8 is taken into a signal generation circuit. The signal generation circuit recognizes the image Bs ′ of the beam spot Bs and the image P ′ of the pupil P from the image, and calculates the positional relationship between the two images Bs ′ and P ′.

For example, as shown in FIG. 24A, when the positional relationship between the images Bs ′ and P ′ is V, the positional relationship between the pupil P and the condensing points P1 and P2 is inappropriate, and FIG. When the positional relationship between the images Bs ′ and P ′ is V ₀ , it is assumed that the positional relationship between the pupil P and the condensing points P1 and P2 is appropriate, and this positional relationship V ₀ is set as the target positional relationship V _{0. Set} to ₀ .

In this case, the detection-system signal generation circuit calculates the actual positional relationship V between the images Bs ′ and P ′ based on the image captured by the detection-system camera 8, and the positional relationship V and the target positional relationship V ₀ . A signal (V−V ₀ ) indicating the difference is generated. This signal is a shift signal indicating a shift between the pupil P and the focal points P1 and P2. The signal generation circuit generates this shift signal in real time every time the camera 8 captures an image (usually every 1/30 seconds).

  Therefore, the three-dimensional display of each embodiment controls the position of the condensing points P1 and P2 so that the deviation signal generated in real time becomes zero, and thereby the positional relationship between the condensing points P1 and P2 and the pupil P. Can be kept in an appropriate positional relationship.

  The example of the use of the three-dimensional display of this embodiment is shown below.

・ Microscope display (If the horizontal and vertical magnifications are matched, the entire magnified image can be seen naturally.)
・ Surgery observation display ・ Surgery simulation display ・ Air traffic controller 3D display ・ CADAM design data display ・ Amusement display ・ Car display (car navigation system information output, safety display)
・ Video phone display ・ Mobile phone display ・ Personal computer display ・ TV monitor

It is a figure which shows a mode that an observation eye observes a solid. It is a figure which shows a mode that the pinhole board has been arrange | positioned just before the pupil P of an observation eye. It is a figure explaining the relationship between the number of pinholes, and adjustment parallax. It is a figure explaining the principle of embodiment. It is a figure which shows the right eye system of 1st Embodiment. It is a figure explaining operation | movement of Z tracking mechanism. It is a figure explaining operation | movement of an XY tracking mechanism. It is a figure which shows the right eye system of 2nd Embodiment. It is a figure which shows the right eye system (and left eye system) of 3rd Embodiment. FIG. 10 is a partially enlarged view of FIG. 9. It is a figure explaining the effect | action of the microprism array. It is a figure which shows the modification of the microprism array. It is a figure which shows the right eye system of 4th Embodiment. It is the elements on larger scale of FIG. It is a figure which shows the right eye system of 5th Embodiment. It is a figure which shows the right eye system of 6th Embodiment. It is a figure which shows the left eye system of 7th Embodiment. It is the figure which looked at the right eye system of an 8th embodiment from the top. It is the figure which looked at the right eye system of an 8th embodiment from the left. It is a figure explaining the effect | action of the one-dimensional diffusion plate. It is the figure which looked at the right eye system of a 9th embodiment from the top. It is the figure which looked at the right eye system of a 9th embodiment from the left. It is a figure which shows embodiment of a detection system. It is a figure which shows the image which the camera 8 image | photographed. It is a figure which shows the right eye system of 9th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Observation eye, 2 ... Solid, 31, 32 ... Transmission type two-dimensional spatial light modulator, 4 ... Half mirror, 5 ... Deflector, 6 ... Reflector, 7 ... One-dimensional diffuser plate, 8 ... Camera, 9 ... Micro prism array, 10 ... light guide plate, P ... pupil, B1, B2 ... light beam, P1, P2 ... condensing point, S1, S2 ... point light source, Sf ... light source unit, Sm ... light source for detection, Lc ... cylindrical lens, MA ... Micromirror array

Claims (15)

An optical system that generates a plurality of condensed light beams that individually collect light at a plurality of points on the pupil of the observation eye that are separated from each other;
A spatial light modulation element that provides an amplitude distribution equivalent to each of the plurality of light beams directed to the plurality of points when a solid is arranged in front of the observation eye for each of the plurality of collected light beams. A three-dimensional display. The three-dimensional display according to claim 1,
The optical system is
Multiple point sources,
An integrated optical system for superimposing a plurality of light beams emitted from the plurality of point light sources;
A three-dimensional display comprising: a condensing optical system that condenses a plurality of light beams emitted from the integrated optical system at the plurality of points. The three-dimensional display according to claim 2,
The location of the spatial light modulator is
The three-dimensional display, which is each of a plurality of optical paths between the plurality of point light sources and the integrated optical system. The three-dimensional display according to claim 2,
The location of the spatial light modulator is
An optical path between the integrated optical system and the condensing optical system;
The plurality of point light sources and the spatial light modulator are:
A three-dimensional display characterized in that a plurality of condensed light fluxes having different amplitude distributions are generated in a time division manner. The three-dimensional display according to claim 1,
The optical system is
A point light source,
A three-dimensional display comprising: a separation and condensing optical system that separates a light beam emitted from the point light source into a plurality of light beams superimposed on each other, and collects the plurality of light beams at the plurality of points. The three-dimensional display according to claim 5,
The location of the spatial light modulator is
An optical path between the separated condensing optical system and the point light source;
The spatial light modulation element and the separation condensing optical system are:
A three-dimensional display characterized in that a plurality of condensed light beams having different amplitude distributions are generated by space division. The three-dimensional display according to claim 6,
The separation condensing optical system is
A three-dimensional display characterized by being a microprism array. The three-dimensional display according to claim 6,
The separation condensing optical system is
A three-dimensional display characterized by being a micromirror array. In the three-dimensional display as described in any one of Claims 1-8,
The arrangement direction of the plurality of points is
The left-right direction of the observer,
A three-dimensional display characterized by further comprising diverging means for extending a condensing point of the plurality of condensed light beams in a vertical direction of the observer. In the three-dimensional display as described in any one of Claims 1-9,
The plurality of condensed light fluxes are passed through corresponding light restricting portions, and a real image of the light restricting portion is formed on the observation eye by a condensing optical system different from the plurality of condensing optical systems. A featured 3D display. In the three-dimensional display as described in any one of Claims 1-10,
A three-dimensional display, further comprising control means for causing the positions of the condensing points of the plurality of condensed light beams to follow the position of the pupil. The three-dimensional display according to claim 11,
The control means includes
A three-dimensional display characterized by having a light deflection function in which a deflection direction is variable in order to change a position of a condensing point of the plurality of condensed light beams. The three-dimensional display according to claim 11 or 12,
The control means includes
In order to detect the position of the pupil, a camera capable of photographing the periphery of the observation eye is used. The three-dimensional display according to claim 13,
The control means includes
Projecting a reference pattern via the optical system, the position of the condensing point of the condensed light flux so that the positional relationship between the image of the reference pattern and the image of the pupil in the image acquired by the camera is maintained A three-dimensional display characterized by controlling. In the three-dimensional display as described in any one of Claims 12-14,
The control means includes
A three-dimensional display, wherein a modulation pattern of the spatial light modulation element is changed according to the position of the pupil.

Images