Image display apparatus

An image display apparatus of the present technology includes a first lens unit (70), a second lens unit (80), and a microlens array (50). The second lens unit (80) eccentrically faces the first lens unit (70). The microlens array (50) is disposed at a first conjugate position (K1) based on the first and second lens units (70, 80).

CROSS REFERENCE TO PRIOR APPLICATION

This application is a National Stage Patent Application of PCT International Patent Application No. PCT/JP2020/010289 (filed on Mar. 10, 2020) under 35 U.S.C. § 371, which claims priority to Japanese Patent Application No. 2019-052525 (filed on Mar. 20, 2019), which are all hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present technology relates to an image display apparatus.

BACKGROUND ART

In recent years, a technique of applying an optical system capable of enlarging the angle of view of an image has been proposed for a head part fitting type display such as a head-mounted display. For example, Patent Literature 1 discloses an optical system in which a diffusion optical element whose incident surface or emission surface serves as a diffusion surface is disposed between a transmissive display element and an eyepiece optical system, and the diffusion surface of the diffusion optical element has a shape along the field curvature of the eyepiece optical system.

In the above optical system, the image on the transmissive display element is converted into a display image for compensating the field curvature of the eyepiece optical system by the diffusion optical element. Thus, even if the eyepiece optical system for enlarging and observing the display image has the field curvature, an image of high resolution without blurring over the entire angle of view can be observed.

CITATION LIST

Patent Literature

DISCLOSURE OF INVENTION

Technical Problem

As described above, there is a need for a technique of presenting an enlarged image to a user in a head part fitting type display such as a head mounted display.

In view of the circumstances described above, the present technology provides, for example, an image display apparatus capable of presenting an enlarged image to a user.

Solution to Problem

In order to solve the above problem, an image display apparatus according to an embodiment of the present technology includes a first lens unit, a second lens unit, and a microlens array.

The second lens unit eccentrically faces the first lens unit.

The microlens array is disposed at a first conjugate position based on the first lens unit and the second lens unit.

An eye of a user may be placed at a second conjugate position different from the first conjugate position based on the first lens unit and the second lens unit.

The image display apparatus may further include a light emitting unit that emits light toward the microlens array, and the light emitting unit may control light that enters the microlens array.

The light emitting unit may control the light that enters the microlens array by changing an emission position or emission direction of the light.

The light emitting unit may be a spatial light modulator or a microdisplay and may change the emission position of the light that enters the microlens array.

The light emitting unit may be a MEMS array and may change the emission direction of the light that enters the microlens array.

The light emitting unit may control the light that enters the microlens array to be refracted by the microlens array and to be parallel light.

The second lens unit may convert light refracted by the first lens unit into divergent light.

The light emitting unit may control the light that enters the microlens array to be refracted by the microlens array and to be convergent light.

The second lens unit may convert light refracted by the first lens unit into substantially parallel light.

The image display apparatus may further include a diaphragm that is disposed between the microlens array and the light emitting unit and restricts the light that enters the microlens array.

The diaphragm may include an aperture and restrict the light that enters the microlens array on the basis of an arrangement of the aperture.

The first lens unit may be a transmissive or reflective hologram lens, and the second lens unit may be a reflective hologram lens.

The microlens array may include a plurality of lenses, and the light emitting unit may include a plurality of regions corresponding to the plurality of lenses and vary output amounts of light for each of the regions.

The second lens unit may be disposed at a position farther from the eye of the user than the first lens unit.

Each of the first lens unit and the second lens unit may have a central axis, and the central axis of the first lens unit may be disposed at a position farther from the eye of the user than the central axis of the second lens unit.

The first lens unit may be a transmissive or reflective eccentric lens, and the second lens unit may be a reflective eccentric lens.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present technology will be described with reference to the drawings.

First Embodiment

[Configuration of Image Display Apparatus]

FIG.1is a schematic diagram showing in a simplified manner a configuration example of an optical system of an image display apparatus according to an embodiment of the present technology, and is a diagram showing a light ray tracing result in the optical system. As shown inFIG.1, an image display apparatus100includes a light source10, a condenser lens20, a spatial light modulator (SLM)30, a first diaphragm40, a microlens array50, a second diaphragm60, a first lens unit70, and a second lens unit80. Note that X, Y and Z axes illustrated inFIG.1respectively represent directions of three axes orthogonal to each other. The same applies to subsequent figures.

The light source10is typically a coherent light source such as a laser, but is not limited thereto. The light source10may be a point light source or a collimated light source. Light of the light source10is emitted toward the condenser lens20.

The condenser lens20is a lens used to collect light emitted by the light source10. Light collected by the condenser lens20is emitted toward the SLM30. The condenser lens20may be a single lens or lenses in combination. The condenser lens20is arranged on a light entrance side of the SLM30to face the light source10.

The SLM30is a device that modulates light from the light source10by electrically controlling a spatial distribution of the light (for example, amplitude, phase, and polarization). The light modulated and emitted by the SLM30enters the microlens array50. The SLM30is an example of “light emitting unit” in the claims.

The SLM30diffracts light emitted from the condenser lens20. The diffracted light thus generated is emitted toward the microlens array50. The SLM30of this embodiment is typically a transmissive spatial light modulator, but is not limited thereto. The SLM30may be, for example, a reflective spatial light modulator.

The first diaphragm40is a shield for adjusting the light amount of the diffracted light diffracted by the SLM30and is provided between the SLM30and the microlens array50. The first diaphragm40has apertures H1, H2, and H3that allow the passage of the diffracted light from the SLM30(seeFIG.2). The apertures H1, H2, and H3are provided in the first diaphragm40at predetermined intervals separate from each other.

The first diaphragm40restricts the light that enters the microlens array50in the diffracted light diffracted by the SLM30. This suppresses disturbance of a reproduced image (hologram image) reproduced by the SLM30.

The microlens array50is provided between the first diaphragm40and the second diaphragm60and is disposed at a conjugate position K1based on the first lens unit70and the second lens unit80(position at which the diffracted light diffracted by the SLM30is emitted toward the first lens unit70). The conjugate position K1is an example of a “first conjugate position” in the claims. The microlens array50includes a plurality of convex lenses50adisposed along a uniaxial direction. Note that the above-mentioned word “conjugate” means that the relationship between two having an arbitrary relationship does not change even if both of them are interchanged, and the “conjugate position” means the positions thereof. This meaning also applies to the following description.

The convex lens50ahas a curved surface of a predetermined radius of curvature on the first lens unit70side and has a curved surface of a smaller radius of curvature than the above radius of curvature on the light source10side.

The convex lens50ais typically a biconvex lens, but is not limited thereto. The convex lens50amay be, for example, a plano-convex lens or a convex meniscus lens. The convex lens50amay be made of, for example, glass, plastic, quartz, or fluorite, but is not limited to these materials.

The number of convex lenses50ais not particularly limited. However, if the number of lenses is too small, this will result in a small number of light rays and in poor visibility of a reproduced image. If the number of lenses is too large, this will result in a local minimum radius of curvature of the convex lens50aand may cause deterioration of a reproduced image due to design errors during lens manufacturing. Thus, for example, the number of convex lenses50ais favorably not less than 5 and not greater than 50. In this case, the number of rows of the convex lenses50aarranged in the Z-axis direction orthogonal to a direction in which the convex lenses50aare arranged is favorably not less than 5 and not greater than 50. The convex lens50ahas a function of refracting the diffracted light diffracted by the interference fringes displayed on the SLM30and of guiding the light to the first lens unit70.

The second diaphragm60is a shield for adjusting the light amount of the diffracted light refracted by the microlens array50and is disposed between the first lens unit70and the microlens array50. The second diaphragm60is disposed at a position near the surface of the microlens array50(convex lenses50a) on the first lens unit70side.

The second diaphragm60has apertures that allow the passage of the refracted light from the microlens array50. The plurality of apertures is provided in the second diaphragm60at predetermined intervals in a direction in which the plurality of convex lenses50ais arranged. Note that the second diaphragm60may be omitted as necessary.

The first lens unit70is a lens for converging the diffracted light refracted by the microlens array50. The first lens unit70has a central axis X1. The central axis X1is the axis of the first lens unit70that passes through the center of the first lens unit70in the longitudinal direction.

The first lens unit70is disposed so as to eccentrically face the second lens unit80on the light entrance side relative to the second lens unit80. The “eccentrically” means that the central axis X1of the first lens unit70and the central axis X2of the second lens unit80, which will be described later, are not coaxially positioned.

Here, in this embodiment, the central axis X1and the light source10are disposed at positions farther from the user's eye than the central axis X2of the second lens unit80. Here, the first diaphragm40, the microlens array50, and the second diaphragm60may be disposed on the central axis X1.

The first lens unit70further refracts the diffracted light refracted by the convex lenses50a, to image the diffracted light between the first lens unit70and the second lens unit80. As a result, imaging points P1, P2, and P3are formed on an image plane S1. Here, the image plane S1is conjugate to a retina S3of the user.

Here, in this embodiment, the first lens unit70and the second lens unit80have a point-symmetrical relationship with each other, with the imaging point P2formed by the first lens unit70as the center.

The first lens unit70is favorably a transmissive eccentric convex lens. As a result, as shown inFIG.1, the light source10can be disposed on the side on which the eyes of the user are placed, and when the image display apparatus100is applied to eyewear such as a head mounted display (hereinafter, referred to as “HMD”) or the like, the apparatus configuration of the eyewear can be made compact as compared to the configuration shown inFIG.6to be described later.

The first lens unit70is typically a transmissive eccentric convex lens, but it is not limited thereto. For example, the first lens unit70may be a transmissive or reflective hologram lens or may be a diffractive lens. Note that the “eccentric” described above means a deviation between the central axis X1of the first lens unit70and the imaging point P2.

The first lens unit70may be made of, for example, glass, plastic, quartz, or fluorite, but is not limited to these materials.

The first lens unit70of this embodiment has, for example, a function of correcting the chromatic dispersion of the diffracted light diffracted by the interference fringes displayed on the SLM30, and the chromatic dispersion of the diffracted light caused by the second lens unit80. Thus, the image quality deterioration of the reproduced image (hologram image) to be presented to the user is suppressed.

As shown inFIG.1, the second lens unit80is disposed so as to face the user's eye at a predetermined interval. The second lens unit80has the central axis X2. The central axis X2is the axis of the second lens unit80that passes through the center of the second lens unit80in the longitudinal direction.

In this embodiment, the second lens unit80may be disposed at a position farther from the user's eye than the first lens unit70. In this case, the user's eye is disposed at the conjugate position K2different from the conjugate position K1, which is based on the first lens unit70and the second lens unit80(a position at which the diffracted light reflected by the second lens unit80enters the user's eye). The conjugate position K2is an example of a “second conjugate position” in the claims. The distance between the second lens unit80and the user's eye is, for example, 15 mm or more and 50 mm or less.

The second lens unit80converts the diffracted light, which is refracted by the first lens unit70and imaged at the imaging points P1, P2, and P3, into substantially parallel light. As a result, imaging points P4, P5, and P6are formed on the retina S3of the user's eye. The imaging points P4, P5, and P6and the imaging points P1, P2, and P3are conjugate to each other, respectively.

The second lens unit80is typically a reflective eccentric convex lens, but it is not limited thereto. For example, the second lens unit80may be a reflective hologram lens or may be a diffractive lens. Note that the “eccentric” described above means a deviation between the central axis X2of the second lens unit80and the imaging point P2.

The second lens unit80may be made of, for example, glass, plastic, quartz, or fluorite, but is not limited to these materials.

The second lens unit80of this embodiment has a function of correcting the aberration caused by the fact that the first lens unit70is eccentric. Thus, the eccentric aberration by the first lens unit70is canceled by the second lens unit80, so that a magnification optical system of small aberration is achieved.

The configuration example of the optical system of the image display apparatus100has been described above in a simplified manner. Each of the constituent elements described above may be configured using a general-purpose member or configured using a member specialized for a function of each constituent element. Such a configuration may be changed as appropriate according to a technical level necessary every time the present technology is practiced.

[Operation of Image Display Apparatus]

Next, the operation of the optical system of the image display apparatus100will be described as appropriate with reference to the drawings.

First, light emitted from the light source10is collected by the condenser lens20, and the collected light is emitted onto the SLM30. The light emitted onto the SLM30is diffracted by the interference fringes, part of which is displayed on the SLM30, and enters the microlens array50.

At this time, the intensity distribution (intensity ratio) of the light emitted to the light source10may be different for each of regions30a,30b, and30cof the SLM30corresponding to each of the plurality of convex lenses50a. Thus, it is possible to equalize the intensity distribution of the diffracted light diffracted in each of the regions30a,30b, and30cand to reduce unevenness in the light amount and a decrease in luminance. Note that, in the following description, the diffracted light diffracted by the SLM30will be referred to as light rays r1, r2, and r3for convenience of description.

The light rays r1, r2, and r3traveling straight toward the microlens array50form focal points F1by the first diaphragm40in the respective apertures H1, H2, and H3provided in the first diaphragm40, and further form focal points F2by passing through the convex lenses50a(seeFIG.2).

Here, the convex lens50ahas a curved surface of a predetermined radius of curvature on the light source10side, and has a curved surface of a larger radius of curvature than the above radius of curvature on the first lens unit70side. Thus, an angle θ2formed by the light rays r1and r3refracted by the convex lens50ais larger than an angle θ1formed by the light rays r1and r3incident on the convex lens50a.

Thus, the focal length of the focal point F2(the distance between the convex lens50aand the focal point F2) is shorter than the focal length of the focal point F1(the distance between SLM30and the focal point F1). Therefore, the light rays r1and r3will form an image at a position farther from the SLM30as compared with the case where there is no microlens array50, and the angle of view of the image is significantly larger than that of the image at the focal point F1. That is, an enlarged image in which the angle of view of the image drawn by the SLM30is enlarged by the microlens array50is presented to the user.

FIGS.2to5are diagrams each showing a light ray tracing result of the optical system of the image display apparatus100.FIGS.2and4are schematic diagrams each showing the periphery of the microlens array50of the optical system in an enlarged manner. Further,FIGS.3and5are schematic diagrams each showing a configuration example of the periphery of the first and second lens units70and80of the optical system.

Control Example 1

The SLM30is configured to be capable of controlling the emission positions of the light rays r1, r2, and r3such that only the light rays r1, r2, and r3having predetermined angular components pass through the apertures H1, H2, and H3of the first diaphragm40. Here, as shown inFIG.2, the SLM30of this embodiment controls the light rays r1, r2, and r3such that only the light rays r1and r3, which will become parallel light after being refracted by the microlens array50, and the light rays r2, which will pass through the center of the convex lenses50awhile being parallel, pass through the apertures H1, H2, and H3.

Thus, as shown inFIG.3, the light rays r1and r3refracted by the microlens array50and the light rays r2passing through the microlens array50are projected at infinity positions by the first lens unit70. The light rays r1, r2, and r3projected at the infinity positions with respect to the first lens unit70are then refracted by the first lens unit70to form an image at a position closer to the second lens unit80than to the image plane S1. In the control example 1, the focal length of the first lens unit70is set such that the imaging points P1, P2, and P3are formed at positions closer to the second lens unit80than to the image plane S1. Note that the image surface S1is a virtual surface that forms imaging points at which the light rays r1, r2, and r3refracted by the first lens unit70and converted into substantially parallel light rays by the second lens unit80are imaged. The same applies to the following description.

Here, if the SLM30controls the light rays r1, r2, and r3as in the control example 1, the forming positions of the imaging points P1, P2, and P3are closer to the second lens unit80than to the image plane S1, and the light rays r1, r2, and r3to be reflected on the user's eye by the second lens unit80are delivered to the user's eye as divergent light rather than substantially parallel light. As a result, an image plane S2is virtually formed, on which a virtual image is projected at a position at a finite distance from the user's eye (for example, a position separated from the second lens unit80by approximately 1 m).

Control Example 2

Further, as shown inFIG.4, the SLM30of this embodiment is also capable of controlling the light rays r1, r2, and r3such that only the light rays r1, r2, and r3that become convergent light after being refracted by the microlens array50pass through the apertures H1, H2, and H3.

Specifically, for example, if the configuration around the microlens array50in the optical system of the image display apparatus100is as shown inFIG.4, the SLM30moves, as shown in the figure, the light ray trajectories of the light rays r2and r3passing through the aperture H1from the left side toward the inside, and moves the light ray trajectories of the light rays r1and r3passing through the aperture H2toward the inside. Further, the SLM30moves the light ray trajectories of the light rays r1and r2passing through the aperture H3from the right side toward the inside.

Thus, the light rays r1, r2, and r3refracted by the microlens array50are projected at positions at finite distances by the first lens unit70. The light rays r1, r2, and r3projected at the positions at finite distances with respect to the first lens unit70are then refracted by the first lens unit70and form an image on the image plane S1. In the control example 2, a projection distance in which the light rays r1, r2, and r3are projected (finite distance D from the first lens unit70shown inFIG.5) is set such that the imaging points P1, P2, and P3are formed on the image plane S1.

That is, if the SLM30controls the light rays r1, r2, and r3as in the control example 2, the forming positions of the imaging points P1, P2, and P3are moved from the positions shown inFIG.3to the first lens unit70side, and the imaging points P1, P2, and P3coincide with the image plane S1as shown inFIG.5. As a result, the light rays r1, r2, and r3to be reflected on the user's eye by the second lens unit80are converted into substantially parallel light by the second lens unit80and then delivered to the user's eye. Thus, an image plane S2is virtually formed, on which a virtual image is projected at an infinity position with respect to the user's eye (for example, a position separated from the second lens unit80by approximately 10 m).

From the above description, the SLM30of this embodiment is capable of controlling the light rays r1, r2, and r3to move the forming positions of the imaging points P1, P2, and P3between the first lens70and the second lens unit80. That is, the SLM30is capable of setting any position for a virtual image distance of a virtual image to be presented to the user.

Note that the control examples 1 and 2 have been described assuming that the SLM30moves all of the imaging points P1, P2, and P3, but the present technology is not limited thereto. The SLM30may vary the forming positions of the imaging points P1, P2, and P3. Thus, for example, the depth of the virtual image projected on the image plane S2is expressed, and a three-dimensional image of the virtual image can be obtained. This makes it possible to solve the so-called “vergence-accommodation conflict” indicating an imbalance in eye function between vergence and accommodation.

In the first embodiment, the diffracted light that enters the microlens array50is controlled by the SLM30, but the present technology is not limited thereto. For example, the diffracted light that enters the microlens array50may be restricted on the basis of the diameter of each of the apertures H1, H2, and H3of the first diaphragm40or the arrangement of each of the apertures H1, H2, and H3. In this case, for example, the apertures H1, H2, and H3formed in the first diaphragm40are arranged at positions through which only the light rays r1, r2, and r3that will become parallel light or convergent light after being refracted by the microlens array50pass, so that the virtual image distance of a virtual image to be presented to the user can be set to any position.

FIG.6is a schematic diagram showing in a simplified manner a configuration example of an optical system of an image display apparatus according to a modified example of the first embodiment. In the optical system of the image display apparatus100, the first lens unit70is a transmissive eccentric convex lens, but is not limited thereto. For example, as shown inFIG.6, the first lens unit70may be a reflective eccentric convex lens. Note that, inFIG.6, the components similar to those inFIG.1will be denoted by similar reference symbols, and description thereof will be omitted.

Second Embodiment

FIG.7is a diagram showing a light ray tracing result of an optical system of an image display apparatus according to a second embodiment of the present technology and is a diagram showing the periphery of a microlens array50of the optical system in an enlarged manner. Hereinafter, the components similar to those in the first embodiment will be omitted from the drawings or will be denoted by similar reference symbols and description thereof will be omitted.

[Configuration of Image Display Apparatus]

The second embodiment of the present technology is different from the first embodiment in that a microdisplay90is employed instead of the light source10and the SLM30of the first embodiment. This configuration provides an optical engine having a light ray width corresponding to the size of the microdisplay90. The microdisplay90is an example of a “light emitting unit” in the claims.

The microdisplay90is, for example, an ultra-compact display of less than one inch having a resolution of a predetermined pixel or more. The microdisplay90may be a self-luminous microdisplay or may be a transmissive or reflective microdisplay with a light source block. Note that in the following description the light emitted from the microdisplay90will be referred to as light rays r4to r7for convenience of description.

[Operation of Image Display Apparatus]

As shown inFIG.7, the microdisplay90is configured to be capable of controlling the light ray trajectories of the light rays corresponding to respective pixels G by changing the display positions of the pixels G. Therefore, the microdisplay90of this embodiment is capable of controlling the emission positions of the respective light rays r4, r5, r6, and r7such that only the light rays r4, r5, r6, and r7that become parallel light or convergent light after being refracted by the microlens array50pass through the apertures H.

As a result, each of the light rays r4, r5, r6, and r7is controlled by the microdisplay90in a manner similar to that in the first embodiment described above (paragraphs [0062] to [0068]), so that the microdisplay90exhibits operations and effects similar to those in the first embodiment (paragraph [0069]).

FIGS.8and9are schematic diagrams each showing a configuration example of an optical system of an image display apparatus according to a modified example of the second embodiment in a simplified manner. The optical system of the image display apparatus of the second embodiment may have a configuration including a prism array120as shown inFIG.8. The prism array120reflects light emitted from the microdisplay90toward the microlens array50. With this configuration, the luminance unevenness of each convex lens50aof the microlens array50is suppressed.

Further, in the optical system of the image display apparatus of the second embodiment, if the first and second lens units70and80are hologram lenses, the microdisplay90may have different output amounts of light for each of regions90a,90b,90c,90d, and90ecorresponding to the respective convex lenses50a.

Thus, for example, if the light emitted from the region90cis most reflected on the first lens unit70or the second lens unit80among the regions90ato90e, the output amounts of light in the regions90a,90b,90d, and90eare increased more than in the region90c, so that the reflection efficiency of the first lens unit70or the second lens unit80corresponding to the regions90a,90b,90d, and90ecan be supplemented, and the intensity distribution of the light reflected by the first lens unit70or the second lens unit80can be made uniform.

Third Embodiment

FIG.10is a diagram showing a light ray tracing result of an optical system of an image display apparatus according to a third embodiment of the present technology and is a diagram showing the periphery of a microlens array50of the optical system in an enlarged manner. Hereinafter, the components similar to those in the first embodiment will be omitted from the drawings or will be denoted by similar reference symbols and description thereof will be omitted.

[Configuration of Image Display Apparatus]

The third embodiment of the present technology is different from the first embodiment in that a micro electro mechanical systems (MEMS) array110is employed instead of the SLM30of the first embodiment. With this configuration, the light utilization efficiency is improved, and an image in which the angle of view is further enlarged by enlarging the scannable range (rotation range) of MEMSs111is also obtained. The MEMS array110is an example of a “light emitting unit” in the claims.

The MEMS array110includes the MEMSs111corresponding to the respective convex lenses50a. The MEMS111is, for example, a MEMS mirror in which various sensors, actuators, electronic circuits, or the like are mounted on a silicon substrate, a glass substrate, an organic material, or the like of a semiconductor.

The MEMS array110of this embodiment includes a plurality of MEMSs111regularly arranged and is configured to be capable of rotating the MEMSs111about the Z-axis as shown inFIG.10. Note that in the following description the light emitted from the light source10will be referred to as light rays r8to r11for convenience of description.

[Operation of Image Display Apparatus]

As shown inFIG.10, the MEMS array110is configured to be capable of controlling the light ray trajectories of the light rays r8, r9, r10, and r11corresponding to the respective MEMSs111by rotating the MEMSs111about the Z-axis. Therefore, the MEMS array110of this embodiment is capable of controlling the emission directions of the respective light rays r8, r9, r10, and r11such that the light rays r8, r9, r10, and r11become parallel light or convergent light after being refracted by the microlens array50.

As a result, each of the light rays r8, r9, r10, and r11is controlled by the MEMS array110in a manner similar to that in the first embodiment described above (paragraphs [0062] to [0068]), so that the MEMS array110exhibits operations and effects similar to those in the first embodiment (paragraph [0069]).

FIG.11is a schematic diagram showing a configuration example of an optical system of an image display apparatus according to a modified example of the third embodiment in a simplified manner. As shown inFIG.11, the optical system of the image display apparatus of the third embodiment may have a configuration including the MEMS111and a prism array120instead of the SLM30. The prism array120further reflects light from the light source10reflected by the MEMS111toward the microlens array50. With this configuration, for example, an effect of enlarging the light ray width can be obtained.

Although the embodiments of the present technology have been described above, the present technology is not limited to the first to third embodiments described above, and of course various modifications may be made thereto.

Further, the image display apparatus of the present technology is typically applied to eyewear such as an HMD, but the application is not limited thereto. The image display apparatus of the present technology may be applied to various apparatuses capable of displaying an image.

In addition, the effects described herein are not limitative, but are merely descriptive or illustrative. In other words, the present technology may provide other effects apparent to those skilled in the art from the description herein, in addition to, or instead of the effects described above.

The favorable embodiments of the present technology have been described above in detail with reference to the accompanying drawings. However, the present technology is not limited to these examples. It is clear that persons who have common knowledge in the technical field of the present technology could conceive various alternations or modifications within the scope of the technical idea described in the claims. It is understood that of course such alternations or modifications also fall under the technical scope of the present technology.

Note that the present technology may also take the following configurations.

a first lens unit;

a second lens unit eccentrically facing the first lens unit; and

a microlens array disposed at a first conjugate position based on the first lens unit and the second lens unit.

(2) The image display apparatus according to (1), in which

an eye of a user is placed at a second conjugate position different from the first conjugate position based on the first lens unit and the second lens unit.

(3) The image display apparatus according to (1) or (2), further including

a light emitting unit that emits light toward the microlens array, in which

the light emitting unit controls light that enters the microlens array.

(4) The image display apparatus according to (3), in which

the light emitting unit controls the light that enters the microlens array by changing an emission position or emission direction of the light.

(5) The image display apparatus according to (3) or (4), in which

the light emitting unit is a spatial light modulator or a microdisplay and changes the emission position of the light that enters the microlens array.

(6) The image display apparatus according to (3) or (4), in which

the light emitting unit is a MEMS array and changes the emission direction of the light that enters the microlens array.

(7) The image display apparatus according to any one of (3) to (6), in which

the light emitting unit controls the light that enters the microlens array to be refracted by the microlens array and to be parallel light.

(8) The image display apparatus according to any one of (3) to (7), in which

the second lens unit converts light refracted by the first lens unit into divergent light.

(9) The image display apparatus according to any one of (3) to (8), in which

the light emitting unit controls the light that enters the microlens array to be refracted by the microlens array and to be convergent light.

(10) The image display apparatus according to any one of (3) to (9), in which

the second lens unit converts light refracted by the first lens unit into substantially parallel light.

(11) The image display apparatus according to any one of (3) to (10), further including

a diaphragm that is disposed between the microlens array and the light emitting unit and restricts the light that enters the microlens array.

(12) The image display apparatus according to (11), in which

the diaphragm includes an aperture and restricts the light that enters the microlens array on the basis of an arrangement of the aperture.

(13) The image display apparatus according to any one of (3) to (12), in which

the first lens unit is a transmissive or reflective hologram lens, and

the second lens unit is a reflective hologram lens.

(14) The image display apparatus according to (13), in which

the microlens array includes a plurality of lenses, and

the light emitting unit includes a plurality of regions corresponding to the plurality of lenses and varies output amounts of light for each of the regions.

(15) The image display apparatus according to any one of (2) to (14), in which

the second lens unit is disposed at a position farther from the eye of the user than the first lens unit.

(16) The image display apparatus according to any one of (2) to (15), in which

each of the first lens unit and the second lens unit has a central axis, and

the central axis of the first lens unit is disposed at a position farther from the eye of the user than the central axis of the second lens unit.

(17) The image display apparatus according to any one of (1) to (16), in which

the first lens unit is a transmissive or reflective eccentric lens, and

the second lens unit is a reflective eccentric lens.

REFERENCE SIGNS LIST