JP2004029236A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To observe an enlarged image by a single eye and also to observe a normal image by both eyes. <P>SOLUTION: Light from a surface light source 502 reaches pupils 106 by passing through a picture display element 107 after passing through the aperture part B of a barrier element 501. The enlarged image is observed by the single eye in the case of reducing the aperture area of the aperture part B, and also the normal image is observed by both eyes in the case of increasing the aperture area of the aperture part B. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image display device that is arranged near an eyeball of an observer and displays an enlarged virtual image.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a head-mounted display device (hereinafter, referred to as an HMD) to be mounted on a head has been configured so that an enlarged virtual image can be visually recognized by a single eye.
[0003]
For example, FIG. 8 is a diagram showing the structure of an HMD described in Japanese Patent Application Laid-Open No. H10-170860, in which an enlarged virtual image can be visually recognized by a flat backlight 800, a transmissive LCD 801 and an eyepiece 802. FIG. 9 is a diagram showing the structure of an HMD described in JP-A-5-328261 or JP-A-6-43391. An enlarged virtual image is formed by a video display element 900, a micro lens 901 and a condenser lens 902. Can be visually recognized.
[0004]
[Problems to be solved by the invention]
However, the above-described HMD has a problem that, although it is possible to observe an enlarged image with a single eye, it is not possible to observe a normal image with both eyes from a distant distance. For example, in the HMD described in JP-A-10-170860, a normal image cannot be observed with both eyes (although the light use efficiency is improved and the device is thin). In the HMDs described in JP-A-5-328261 and JP-A-6-43391, although a compact and high-resolution image can be displayed, a field lens is used, so that observation at a distant distance is not possible. In other words, in these HMDs, since the microlenses are arranged at the positions shown in the figure, moiré occurs at the boundary between the microlens and the boundary between the pixels, which makes it difficult to observe from a distant image with both eyes. Not suitable.
[0005]
Accordingly, it is an object of the present invention to provide an image display device that enables both enlarged image observation with a single eye and normal image observation with both eyes.
[0006]
[Means for Solving the Problems]
The present invention has been made in consideration of the above circumstances, and has a first illuminating unit configured by two-dimensionally arranging a plurality of minute point light sources, and bending light from each minute point light source toward an eyeball. A first optical member, a second optical member that converges light from each minute point light source and converts it into a substantially parallel light beam, and selectively blocks light from each minute point light source as a whole. An image display element for displaying an image,
Based on the fact that light from each of the minute point light sources is guided to the eyeball, an enlarged virtual image is formed at a position separated by more than the clear vision distance of the eyeball.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0008]
The present invention enables observation of an enlarged virtual image (at a close position) by looking into an image display device, and also enables screen observation at a position remote from the device. is there. In other words, the illumination method from the back of the device can be switched between a micro spotlight illumination method and a uniform illumination method over the entire surface. In the case of a microspotlight illumination method (for example, see FIG. 5A), By looking into the image display device with a single eye, it becomes possible to observe an enlarged virtual image of a rectangular aperture,
In the case where the entire surface is uniformly illuminated (for example, see FIG. 5B), the display screen can be observed with a binocular vision from a distant distance, and the distance between the microlens and the pixel of the display element can be increased. It is possible to suppress occurrence of moiré and occurrence of crosstalk and congestion due to binocular vision.
[0009]
The image display apparatus according to the present invention, for example as shown in FIG. 1, the first illumination means (barrier elements) 101 in which a plurality of minute point light sources A ₁ is constituted by two-dimensionally arranged, each of the minute point light source second converting light from a ₁ and the first optical member 102 that bends in the direction of the eye 106 as indicated by reference numeral 103, into a substantially parallel light beam 105 on which converges the light from the minute point light sources a ₁ an optical member 104, provided with an image display device 107 to each of the micro light source based to selectively block light to a pixel, and displaying an image as a whole from the minute point light sources a _1, and each micro Based on the fact that the light from the point light source is converted into a substantially parallel light flux and then guided to the eyeball 106, an enlarged virtual image is formed at a position that is at least as far as the clear vision of the eyeball.
[0010]
In this case, a prism can be used for the first optical member 102, and a convex lens can be used for the second optical member 104. Further, as shown in FIG. 2, convex lenses may be used for the first optical member (see reference numeral 201) and the second optical member (see reference numeral 203). Further, a color filter may be arranged as shown by reference numeral 108.
[0011]
The image display apparatus according to the present invention, as shown in FIG. 3, a second illumination means 301 in which a plurality of minute point light source A ₂ is constituted by two-dimensionally arranged substantially emits the parallel light beams, each the image display device 107 for displaying the third optical member 102 for bending the light from the minute point light source a ₂ in the direction of the eye, an image as a whole on the basis of selectively blocking the light from the minute point light sources a ₂ Based on the fact that the light from each minute point light source is guided to the eyeball, an enlarged virtual image is formed at a place separated by more than the clear vision distance of the eyeball.
[0012]
In this case, as shown in FIGS. 6A and 6B, a scattering control element 601 is arranged along the image display element 107, and when the scattering control element 601 is made to be in a completely transmitting state, it is enlarged by one eye. It is possible to enable observation of a virtual image (observation at a close position), and to enable observation of an image with both eyes (observation at a distant position) when the scattering control element 601 is in the entire scattering state. good.
[0013]
Here, as the third optical member, a prism (see reference numeral 102 in FIG. 3), a convex lens (see reference numeral 201 in FIG. 4A) and a concave lens (see reference numeral 401 in FIG. 4A), or a combination thereof (See reference numeral 403 in FIG. 4B).
[0014]
Further, as shown in FIG. 5A, the image display device according to the present invention is provided with a third lighting means 502 for emitting light from a two-dimensional plane, and is arranged along the third lighting means 502. Light amount control means 501 having a plurality of openings B arranged two-dimensionally, a first optical member (see reference numeral 201) for bending light passing through each opening B toward the eyeball 106, and each opening A second optical member (see reference numeral 203) for converging the light passing through the portion B and converting the light into a substantially parallel light beam; and opening each light by selectively blocking the light passing through each opening B. And an image display element 107 for displaying an image as a whole. The light amount control means 501 changes the opening area of the opening B (for example, as shown in FIG. Large aperture shown in Fig. 3 (b) The light amount is controlled by switching the state of the opening. When the opening area of the opening is reduced (in the case of the minute opening state shown in FIG. 3A), the light passes through each opening. When an enlarged virtual image is formed at a place separated by more than the clear vision distance of the eyeball based on the converted light being converted into a substantially parallel light flux and guided to the eyeball, and the opening area of the opening is increased ( In the case of the large aperture state shown in FIG. 2B, there can be mentioned an example in which the screen can be observed at a remote position by binocular vision. That is, in the case of the minute aperture state, the divergent light from each minute point light source is converted into substantially parallel light, and the optical axis of the light passes through each pixel of the corresponding image display element and the back of each color filter, and the image display element Can be adjusted to approximately one point on the pupil plane of a single eye that is brought close to a close distance where it cannot be focused physiologically from the display surface of. Therefore, the pixels corresponding to the microlenses corresponding to the minute apertures are arranged so that the optical axis coincides with one point on the pupil plane. At this time, it is desirable that the pixels of the image display element be accurately aligned in order to effectively use the illumination light. Since the opening is to be magnified and observed, it is desirable that the minute opening has a rectangular shape.
[0015]
By setting the focal point of the illumination optical system including the microlens in the vicinity of the minute opening, a virtual image of the opening can be formed at a distance (250 mm∞) at which the eye can be focused. At this time, since the pupil is too close to the display screen, the surface of the screen cannot be observed, and a virtual image is observed, so that an enlarged screen can be observed.
[0016]
The size of the virtual image (display screen) determined by the distance between the display screen and the pupil plane is determined by the maximum incident angle of the outermost ray bundle to the pupil.
[0017]
The enlargement ratio of each pixel (small aperture) and the enlargement ratio of the display screen by the illumination optical system including the microlens are independent of each other, but the size of the aperture is determined so as not to overlap with the adjacent pixels. Therefore, if the distance between the pupil plane and the display screen is L, the diagonal length of the microlens is D, the focal length of the illumination optical system including the microlens is f, and the diagonal length of the aperture is W, If the distance from the pupil plane to the virtual image plane is sufficiently large, W ≦ μxfxD / L may be satisfied.
[0018]
Here, μ is a coefficient indicating an allowable value of pixel overlap determined from the visibility of the observation screen.
[0019]
Also, when observing the screen with binocular vision from a distant position, the barrier element is switched to the transmissive state, eliminating the directivity function of the illumination light, and the liquid crystal display element is viewed from the back as almost uniform backlight light. Irradiate.
[0020]
For this reason, when the microlens is disposed on the front side as in Japanese Patent Application Laid-Open No. H10-170860, the lens action of the microlens causes the convergence of both eyes to intersect at the display element surface from the element surface. Since the screen is displayed at a distant position, the screens overlap and the display screen cannot be observed from a distant distance. Since the overlap between the microlens and the pixel is decentered, crosstalk in which light from the adjacent aperture enters is caused to deteriorate the screen. In addition, moire occurs due to the boundary between the microlenses and the pixel boundary between the display elements, and deteriorates the screen.
[0021]
Note that a convex lens can be used for the first optical member 201 and the second optical member 203 described above.
[0022]
Further, as shown in FIG. 7A, the image display device according to the present invention has a fourth illuminating means configured by two-dimensionally arranging a plurality of small point light sources A3 that emit light according to image information. 701, a first optical member 201 that bends the light from each minute point light source A3 toward the eyeball 106, and a second optical member 203 that converges the light from each minute point light source and converts it into a substantially parallel light flux And a scattering control element 601 arranged along the second optical member 203. When the scattering control element 601 is in the entire transmission state, observation of an enlarged virtual image with one eye (at a close position) Observation) is possible, and when the scattering control element 601 is in the entire scattering state, an image can be observed (observation at a remote position) with both eyes. That is, the fourth illumination unit 701 is configured to display an image as a whole based on the light amount of each minute point light source A3 being independently controlled.
[0023]
Next, effects of the present embodiment will be described.
[0024]
According to the present invention, it is possible to observe an enlarged virtual image (at a close position) by looking into an image display device, and further, to observe a screen at a position distant from the device (by binocular vision at the same magnification). Observation).
[0025]
Further, simple enlargement of a small screen, conversion to another content display, conversion of display direction, and the like are also possible.
[0026]
As a result, a large amount of information that could not be displayed on a small screen of a portable device or the like can be observed in an enlarged display, and the convenience of the portable device has been greatly increased.
[0027]
【Example】
Hereinafter, the present invention will be described in more detail by way of examples.
[0028]
(Example 1)
FIG. 1 is a diagram showing an embodiment of the image display device according to the present invention. In the present embodiment, as shown in the figure, a barrier element (first illuminating means) 101 in which a large number of minute point light sources A1 are arranged in a two-dimensional matrix, and light from each minute point light source A1 A microprism element (first optical member) 102 that bends in the direction, a microconvex lens element (second optical member) 104 that converges light from each minute point light source and converts it into a substantially parallel light beam, and displays an image. The image display device is constituted by the image display element 107 and the color filter 108, and the light emitted from the minute point light source A1 of the barrier element 101 is bent by the micro prism element 102 (see reference numeral 103), and the micro convex lens After being converted into substantially parallel light by the element 104 and passing through the image display element 107 and the color filter 108, they intersect at substantially one point at the position of the pupil 106. It will form the enlarged virtual image from the pupil on one side apart distance above the distinct vision.
[0029]
(Example 2)
FIG. 2A is a diagram showing an embodiment of the image display device according to the present invention. In the present embodiment, as shown in the figure, a barrier element (first illuminating means) 101 in which a large number of minute point light sources A1 are arranged in a two-dimensional matrix, and light from each minute point light source A1 A convex lens 201 that bends in the direction, a micro-convex lens element 203 that converges light from each minute point light source and converts it into a substantially parallel light beam, an image display element 107 that displays an image, and a color filter 108. After forming the display device, light emitted from the minute point light source A1 of the barrier element 101 is bent by the convex lens 201, converted into substantially parallel light by the micro convex lens element 203, and transmitted through the image display element 107 and the color filter 108. At the position of the pupil 106, they intersect at substantially one point, and an enlarged virtual image is formed on one surface that is separated from the pupil by a distance equal to or longer than the clear vision.
[0030]
Reference numeral 204 in FIG. 2 (b) indicates that the above-described convex lens 201 and micro-convex lens 203 are integrated, but the same effect can be obtained by using the member 204 instead of the convex lens 201 or the micro-convex lens 203. Can be obtained.
[0031]
(Example 3)
FIG. 3 is a diagram showing an embodiment of the image display device according to the present invention. In this embodiment, as shown in the figure, a large number of minute light sources A2 that emit a substantially parallel light beam in a direction perpendicular to the surface (that is, in the horizontal direction as indicated by reference numeral 302) are arranged in a two-dimensional matrix. Barrier element (second illumination means) 301, a microprism element (third optical member) 102 for bending light from each minute light source in the direction of the pupil, an image display element 107 for displaying an image, and a color filter 108 The light emitted from the minute point light source A2 of the barrier element 301 is bent by the microprism element 102, intersects at substantially one point at the position of the pupil 106, and the enlarged virtual image is clearly seen from the pupil. Is formed on one surface separated by more than the distance.
[0032]
Note that the small point light source A2 in this embodiment emits a parallel light beam (instead of irradiating divergent light as in the first and second embodiments), so the distance between the barrier element 301 and the microprism element 102 is small. Can be set arbitrarily, but it is preferable to reduce the distance because the apparatus can be downsized.
[0033]
Even in the case where the parallel light beam is like a laser beam, it can be observed as a pixel having a certain size by slightly diffusing the parallel light beam when passing through the optical element on the optical path.
[0034]
(Example 4)
FIG. 4A is a diagram showing an embodiment of the image display device according to the present invention. In the present embodiment, as shown in the figure, the barrier element (second illumination means) 301 used in the third embodiment, a convex lens 201 and a micro concave lens 401 that bend light from each minute point light source in the direction of the pupil are provided. , An image display device including an image display element 107 for displaying an image and a color filter 108, the light emitted from the minute point light source A2 of the barrier element 301 is bent by the convex lens 201, and The positions intersect at approximately one point, and an enlarged virtual image is formed on one surface that is at least as far as clear vision from the pupil.
[0035]
The reference numeral 403 in FIG. 4B indicates that the above-mentioned convex lens 201 and micro concave lens 401 are integrated, but the same effect can be obtained by using the above-mentioned member 403 instead of the convex lens 201 or micro concave lens 401. Can be obtained.
[0036]
(Example 5)
FIG. 5A is a diagram showing an embodiment of the image display device according to the present invention. In the present embodiment, as shown in the figure, a barrier element (light quantity control means) 501 having a large number of openings B arranged two-dimensionally is provided. The light amount is controlled by changing the opening area. On the back of the barrier element 501, a surface light source (third lighting means) 502 is arranged. In addition, a convex lens (first optical member) 201 is arranged along the barrier element 501 so that light that has passed through each opening B is converged and then bent toward the pupil. Further, a micro convex lens (second optical member) 203 is arranged along the convex lens 201, and converts the light passing through each opening B into a substantially parallel light beam.
[0037]
According to this apparatus, when the barrier element 501 is in a minute aperture state as shown in FIG. 5A, the light from the surface light source 502 emits the minute aperture when one eye is brought close as in the second embodiment. Enables observation of an enlarged virtual image. In addition, when the barrier element 501 is in an open state as shown in FIG. 5B, it is possible to observe the screen at a distant position by binocular vision.
[0038]
(Example 6)
FIG. 6A is a diagram showing an embodiment of the image display device according to the present invention. The image display device according to the present embodiment has substantially the same structure as the image display device shown in FIG. 4A, but a scattering control element 601 is arranged on the back of the image display element 107. The scattering control element 601 makes it possible to switch between a full scattering state and a full transmission state, so that an enlarged virtual image can be observed in a full transmission state when one side of the pupil is brought close, and a scattering state at a remote position. Thus, it was possible to observe the screen with binocular vision using scattered light (see FIG. 3B).
[0039]
(Example 7)
In the case where the barrier element has a self-luminous image display function capable of independently controlling the amount of light, a two-dimensional matrix color filter element is disposed on the surface side of the illumination optical system including the microlens, and the color filter is disposed in close proximity to the color filter. A scattering control element may be arranged on the pupil side or on the side opposite to the pupil to switch between the full scattering state and the full transmission state. The details will be described below.
[0040]
FIG. 7A is a diagram showing an embodiment of the image display device according to the present invention. In the present embodiment, the barrier element 701 is configured by two-dimensionally arranging a large number of minute point light sources A3 that emit light according to image information. Further, a convex lens (first optical member) 201 is arranged along the barrier element 701 so that the emitted light is bent in the direction of the pupil, and a micro convex lens (second optical member) 203 is arranged. Is converged and then converted into a substantially parallel light beam. Furthermore, when the scattering control element 601 is arranged along the micro convex lens 203, and the scattering control element 601 is in the entire transmission state, it is possible to observe an enlarged virtual image with one eye. In this case, the image can be observed with both eyes. Note that a color filter 108 is provided so that color display is possible.
[0041]
Although a color filter is used in FIG. 7A, a barrier element (that is, a small point light source A4 that emits each color light including image information) is used instead, as shown in FIG. 7B. (A device having a self-luminous image display function including color information) 710 may be configured.
[0042]
【The invention's effect】
As described above, according to the present invention, it becomes possible to observe an enlarged virtual image (at a close position) by looking into an image display device, and further, to observe a screen at a position distant from the device (1: 1 magnification). Observation with binocular).
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of an image display device according to the present invention.
FIG. 2 is a diagram showing one embodiment of an image display device according to the present invention.
FIG. 3 is a diagram showing one embodiment of an image display device according to the present invention.
FIG. 4 is a diagram showing an embodiment of the image display device according to the present invention.
FIG. 5 is a diagram showing an embodiment of an image display device according to the present invention.
FIG. 6 is a diagram showing an embodiment of the image display device according to the present invention.
FIG. 7 is a diagram showing an embodiment of an image display device according to the present invention.
FIG. 8 is a diagram showing a structure of an HMD described in Japanese Patent Application Laid-Open No. 10-170860.
FIG. 9 is a diagram showing the structure of an HMD described in JP-A-5-328261 and JP-A-6-43391.
[Explanation of symbols]
101 barrier element (first lighting means)
102 Micro prism element (first optical member)
104 Micro convex lens (second optical member)
107 Image display element 201 Convex lens (first optical member)
203 Micro convex lens (second optical member)
301 Barrier element (second lighting means)
501 Barrier element (light quantity control means)
502 Surface light source (third lighting means)
601 scattering control element 701 barrier element (fourth illumination means)
A ₁ minute point light source A ₂ minute point light source A ₃ minute point light source A ₄ minute point light source

Claims (11)

A first illuminating means in which a plurality of minute point light sources are arranged two-dimensionally; a first optical member for bending light from each minute point light source toward an eyeball; and a light from each minute point light source. A second optical member that converts the light into a substantially parallel light beam after being converged, and an image in which each minute point light source is turned into a pixel based on selectively blocking light from each minute point light source, and an image is displayed as a whole. And a display element,
Based on the light from each minute point light source being guided to the eyeball, an enlarged virtual image is formed at a distance greater than or equal to the clear vision distance of the eyeball,
An image display device, characterized in that: The image display device according to claim 1, wherein the first optical member is a prism, and the second optical member is a convex lens. The image display device according to claim 1, wherein the first optical member is a convex lens, and the second optical member is a convex lens. A second illuminating unit configured by two-dimensionally arranging a plurality of minute light sources that emit substantially parallel light beams, a third optical member that bends light from each minute light source toward an eyeball, and An image display element for displaying an image as a whole, with each minute light source as a pixel based on selectively blocking the light of
Based on the light from each minute point light source being guided to the eyeball, an enlarged virtual image is formed at a distance greater than or equal to the clear vision distance of the eyeball,
An image display device, characterized in that: A scattering control element is arranged along the image display element, enabling observation of an enlarged virtual image with one eye when the scattering control element is in the entire transmission state, and when the scattering control element is in the entire scattering state. 5. The image display device according to claim 4, wherein the device enables observation of an image by both eyes. The image display device according to claim 4, wherein the third optical member is a prism. The image display device according to claim 4, wherein the third optical member is a combination of a convex lens and a concave lens. Third illumination means for emitting light from a two-dimensional surface, light quantity control means having a plurality of two-dimensionally arranged openings arranged along the third illumination means, and passing through each of the openings A first optical member that bends incoming light in the direction of the eyeball, a second optical member that converts light that has passed through each opening into a substantially parallel light beam, and selectively blocks light that has passed through each opening. And an image display element for displaying an image as a whole with each opening as a pixel based on the
The light amount control unit is configured to control the light amount by changing the opening area of the opening,
If the opening area of the opening is reduced, based on the light that has passed through each opening being guided to the eyeball, an enlarged virtual image is formed at a distance that is greater than or equal to the clear vision distance of the eyeball,
When the opening area of the opening is increased, it is possible to observe the screen at a distant position by binocular vision,
An image display device, characterized in that: The image display device according to claim 8, wherein the first optical member is a convex lens, and the second optical member is a convex lens. A fourth illuminating unit configured by two-dimensionally arranging a plurality of minute point light sources that emit light corresponding to image information, a first optical member that bends light from each minute point light source toward an eyeball, A second optical member that converges light from each minute point light source and converts the light into a substantially parallel light beam, and a scattering control element arranged along the second optical member,
When the scattering control element is in the entire transmission state, it is possible to observe an enlarged virtual image with one eye, and when the scattering control element is in the entire scattering state, it is possible to observe an image with both eyes,
An image display device, characterized in that: A first illuminating means in which a plurality of minute point light sources are arranged two-dimensionally; a first optical member for bending light from each minute point light source toward an eyeball; and a light from each minute point light source. A second optical member that converts the light into a substantially parallel light beam after being converged, and an image in which each minute point light source is turned into a pixel based on selectively blocking light from each minute point light source, and an image is displayed as a whole. And a display element,
The first optical member is a micro prism, the second optical member is a micro convex lens, and
Based on the light from each minute point light source being guided to the eyeball, an enlarged virtual image is formed at a distance greater than or equal to the clear vision distance of the eyeball,
An image display device, characterized in that:

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