JP2002287077A - Video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a see-through type video display device which can be composed of a small-sized, thin optical system, is applicable to actual spectacle lenses having various curved-surface shapes, and can form excellent video with a wide angle of view. SOLUTION: In a lens 3, a combiner part 4 composed of a translucent reflecting surface is provided and its shape looks like a Fresnel lens formed by connecting discontinuous reflecting surfaces as shown in the figure; and the angles of the reflecting surfaces are so determined that a virtual image of an LCD 2 is correctly formed on the opposite side of the lens 3 from a pupil 6 when viewed from the pupil 6. The power of this virtual image can be varied by varying the shape of the reflecting surface of the combiner part 4. The reflecting surface of the combiner part 4 is formed by connecting the discontinuous reflecting surfaces, so its axis along the optical axis is reducible as well as the Fresnel lens.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device used in front of an observer's eyes, and more particularly to a virtual image of an image displayed on a display device and an external image such as a natural scene in a front view. The present invention relates to a video display device which is provided to an observer while being spatially superimposed.

[0002]

Conventionally, are mounted on the head, there is a video display device for use in observer before eyes, altitude for the aircraft, from which displays flight information such as speed, as a personal theater, Movies, video games, and those that display virtual reality have been developed and commercialized.

[0003] Such video display devices include a see-through type in which the outside world can be seen and a closed type in which the outside world cannot be seen. Closed type is mainly personal theater has been used for, see-through is used to observe by superimposing images formed on the outside of the image. See-through image display apparatus, in addition to the observation optical system be provided as a virtual image to see easily accessible to the observer an image displayed on the video display unit and the image display unit, a beam combiner for polymerizing a video light and external light Is provided. As a beam combiner, a half mirror, a polarization beam splitter, a hologram, or the like is used.

[0004] Among them, a hologram is used, and the paper "Actually wearable see-thorough display u"
sing HOE: ODF 2000, Tokyo, Nov. 16, 2000. P.11
7-120 "shows an example of what is shown in FIG. LCD
Irradiation light 22 emitted from 21 is multiple-reflected in a prism 23 having a curved surface to form a hologram image on the surface of a hologram combiner 24, and the image is observed by eyes 25. On the other hand, light from the outside passes through the hologram combiner 24 and is observed overlapping with the formed hologram image.

[0005]

Generally [0008], a half mirror, a polarizing beam splitter, a hologram or the like, in see-through image display apparatus using a conventional combiner, in order to obtain an image of wide angle of view, the image at the combiner unit Since it is necessary to take in the spread of the luminous flux, a large member is required, which requires a large space in terms of weight and space.

The technique described in the above-mentioned article is intended to save space by transmitting image light using total reflection, but has a curved shape like a spectacle lens actually used. A large amount of aberration is generated on the curved surface, and it can hardly be used for personal purposes having various curved surfaces according to the degree of myopia and hyperopia. Further, the hologram of the combiner size increases even in this case, in order that, thicker lens incorporating a hologram combiner, there is a problem that is not practical.

[0007] Further, even when provided in a separate member from the lens hologram combiner, member becomes thicker with hologram combiner has the problem that before the eyes of the arrangement becomes difficult.

The present invention has been made in view of such circumstances, and can be configured with a compact and thin optical system, can be applied to actual spectacle lenses having various curved shapes, and has a good and wide range. An object of the present invention is to provide a see-through type video display device capable of forming an image with an angle of view.

[0009]

According to a first aspect of the present invention, there is provided an image display apparatus arranged in front of an observer to provide a displayed image and an image of an external object to the observer. Te, comprising: a combiner unit having a reflecting surface, and the outside world object light guiding means for guiding light from the outside to the eye of the observer, and the image forming means for guiding the formed image to the external object light guiding means, wherein the combiner unit Wherein the reflection surface is formed of a plurality of discontinuous surfaces, and has a function of reflecting image light emitted from the image forming means and guiding the image light to an observer's pupil. Item 1).

In this means, light from the image formed by the image forming means is reflected by the combiner and guided to the pupil of the observer. Therefore, for the observer, the image of the external object and the image formed by the image forming means are synthesized and observed.

The reflecting surface of the combiner section in this means is
It is formed from a surface which is discontinuous shape Ruishi the surface of the Fresnel lens. Therefore, the thickness of the combiner portion does not increase, and accordingly, the thickness of the external object light guide unit can be reduced.

The combiner section may be formed inside the external object light guiding means. In this case, even if the combiner section is formed in a discontinuous shape, the surface shape of the external object light guiding means is continuous and its curvature is constant. Can also be designed freely. Therefore, it is possible to manufacture a spectacle that can be used in the same manner as ordinary glasses and can be used even by people with myopia and hyperopia.

[0013] A second means for solving the above-mentioned problems is as follows.
A first means that, image light reflected by the combiner unit, viewed from the observer's pupil, and forms a virtual image of the image to the outside the object side of the external object beam guide means (Claim 2).

In the present means, the light from the image formed by the image forming means, is reflected by the combiner unit guided to the observer's pupil, as seen from the observer's pupil, outside of the external object beam guide means A virtual image of the image is formed on the object side. Therefore, for example, LCD as an image forming means
If a (liquid crystal) display device or the like is used, the first means can be realized by a simple optical system.

[0015] A third means for solving the above problems is as follows.
The first means, wherein the image forming means forms a real image between itself and the combiner section,
Image light reflected by the combiner unit, viewed from the observer's pupil, which is characterized in that forms a virtual image of the real image to the outside the object side of the external object beam guide means (claim 3 ).

In this means, unlike the second means, the intermediate image formed by the image forming means is reflected by the combiner and guided to the pupil of the observer. wherein the external object side of Hikarishirubeko means are so as to form a virtual image of the image. Therefore, so as not to aberration when the intermediate image is reflected by the combiner unit, by forming an intermediate image by the image forming unit, since the aberration is not necessary to correct the at combiner unit, facilitates the design of the combiner unit Become.

A fourth means for solving the above-mentioned problem is:
The second means or the third means, wherein the virtual image formed by the combiner section is formed on an image formed on the surface of the image forming section, or formed between the image forming section and the combiner section. has been a real image, is such that an enlarged or reduced, which is characterized in that the shape of the reflective surface of the combiner unit is selected (claims 4).

In the present means, by the shape of the reflecting surface of the combiner section shaped like a surface of a Fresnel lens for example, to have the effect of the concave mirror and convex mirror combiner unit, the magnification of the original image and the virtual image I try to change it. Therefore, the size of the observed image can be changed according to the design value.

A fifth means for solving the above-mentioned problem is:
Any one of the second to fourth means, wherein the image is emitted from an image formed on the surface of the image forming means, or a real image formed between the image forming means and the combiner section. The optical path length of the principal ray reflected by the combiner and guided to the pupil of the observer is substantially the same for the principal ray emitted from any part of the image or the real image (claim) Item 5).

In the present means, the optical path length of a principal ray emitted from the image or intermediate image, because it is substantially the same irrespective of the portion of the image, aberration is not generated virtual image to be observed. Here, “almost” means within the allowable range of aberration,
It means that there may be a difference in the optical path length. Be the same optical path length may be performed by adjusting the shape of the reflective film of the combiner unit may be performed by adjusting the shape of the image or intermediate image.

A sixth means for solving the above-mentioned problem is as follows.
Be any of the fifth means from said first means, said external object beam guide means is a those characterized by (claim 6) is a lens.

In this means, since the external object light guiding means is constituted by a lens, even when a person with myopia or hyperopia is used, it is possible to compose an image of an external object and a video to clearly see both. it can.

A seventh means for solving the above problem is as follows.
Any one of the first means to the sixth means, which is formed in a spectacle shape (claim 7).

In the present means, since the image display means is formed in the shape of glasses, it can be used in the same way as wearing glasses, and there is no discomfort in wearing. Since all of the first to sixth means are small and lightweight,
This means can be easily realized.

Eighth means for solving the above-mentioned problem is:
Be any of the seventh means from said first means, attached to the eyeglasses, a which is characterized in that it is a structure which can be removed (claim 8).

In the present means, since the structure is such that it can be attached to and detached from the glasses, it can be used only when necessary, and can be used in common, regardless of the frequency of the human glasses used. Can be used.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing an image display device as an example of an embodiment of the present invention, which is formed in a shape of glasses. An LCD 2 as an image display device is attached to the vine unit 1, and an image is formed by the LCD 2. Light from the LCD 2 is applied to a combiner section 4 formed in a lens 3 serving as an external object light guiding means and formed of a translucent reflecting surface, and is reflected there to enter a human pupil.

[0028] That is, the human eye, the image is visible in the outside world was transmitted through the lens 3, a virtual image of LCD2 reflected by the reflecting surface of the combiner unit 4 is observed overlap. In FIG. 1, reference numeral 5 denotes a frame of glasses.

FIG. 2 is a diagram showing a main part of the example of the embodiment shown in FIG. Some lens 3 is combiner unit 4 consisting of semi-transparent reflective surface is provided, the shape is formed is joined together discontinuous reflecting surface, as shown in FIG., As a Fresnel lens has the shape, the angle of each reflective surface, when viewed from the pupil 6, LCD 2
Is correctly formed on the opposite side of the pupil 6 of the lens 3. By changing the shape of the reflective surface of the combiner unit 4, it is possible to change the magnification of the virtual image.

At this time, since the reflecting surface of the combiner section 4 is formed by joining discontinuous reflecting surfaces, the size in the optical axis direction can be reduced similarly to the Fresnel lens. Therefore, the thickness of the lens 3 does not need to be increased, and the lens 3 can be reduced in size and weight, and can be used with almost the same feeling as ordinary glasses. Light 7 from the outside world
Is transmitted through the portion of the lens 3 where the combiner portion 4 is not formed and through the combiner portion 4 to enter the pupil 6.

FIG. 3 is a diagram showing an outline of another embodiment of the present invention. Light emitted from the LCD2 via the relay optical system composed if a reflection type Fresnel lens 8 and reflecting mirror 9, forms an intermediate image 10 to the pupil 6 side of the lens 3. The light emitted from the intermediate image 10 is transmitted to the combiner unit 4.
And a virtual image of the intermediate image 10 is formed on the outside of the lens 3 when viewed from the pupil 6. The configuration and operation of the combiner unit 4 and other configurations and operations are the same as those shown in FIG. A reflection type Fresnel lens 8 becomes if the reflecting mirror 9 relay optical system is placed in a housing together with LCD 2, is fixed to the vine portion 1 of the glasses.

[0032] The reflective surface of the combiner unit 4 may not necessarily be the total reflection surface, it may have a reflectivity which can be reflected with a practically sufficient amount of light from the LCD 2. Further, in the present embodiment, an image is formed on the surface of the LCD 2, and the image is incident on the pupil 6 by the reflection surface of the combiner unit 4. However, the image forming method is not limited thereto, for example, instead of the LCD 2, modulated while scanning the light beam at high speed in accordance with the form image desired, be incident the beam to the pupil 6 by the reflecting surface of the combiner unit 4 This allows the user to recognize the image.

Incidentally, when an LCD is used for image formation, there is a problem of occurrence of aberration as a problematic matter in the optical system as shown in FIGS. Aberration is LCD2
This is caused by the fact that the optical path lengths of the chief rays coming out of the respective portions of the surface or the intermediate image 10 and entering the pupil are different for each of the portions. To prevent this, the inclination and position of each reflection surface of the combiner unit 4, and by changing the curved shape, or the same optical path length of the principal ray,
By changing the shape of the intermediate image 10 by the relay optical system, a method of making the optical path lengths of the principal rays the same can be adopted.

[0034] Further, it is possible to reduce the thickness required on the reflecting surface of the combiner unit 4, and so that to reduce the aberrations, the surface intermediate image is formed is a desired inclination relative to the optical axis of the pupil 6 It is also preferable to change it with a relay optical system so as to have it. Any of these is a matter that can be easily realized by those skilled in the art by the calculation of geometrical optics.

In an actual design, the principal ray spread at a certain angle is emitted from the pupil 6 and is reflected on each reflecting surface of the combiner section 4 to trace the reflecting mirror 9 and the reflective Fresnel lens 8 in reverse. It is easier to design the optical system by finding the conditions that form an image on the surface of the optical system.

FIG. 4 is a schematic diagram showing a mounted state of a video display device according to another embodiment of the present invention as viewed from above. L
The light from the CD 2 is applied to the combiner unit 4 in the lens 3 via the lens 11 and the reflecting mirrors 12 and 8 to form a virtual image of the image formed by the LCD 2. The diopter of the observer can be corrected by moving the lens 11 back and forth or by using a toric lens.

[0037] FIG. 5 shows an outline of an example of another embodiment of the present invention. In this embodiment, the spectacles and the video display device are separate components, and can be mounted on the spectacles and used as needed. That is, the combiner unit 4 is formed inside the flat glass 13 which is an external object light guide unit different from the lens 3 of the glasses.
Irradiating light from the LCD2 is an intermediate image 10 formed by the relay optical system 14, light emitted from the intermediate image 10 is reflected by the reflecting surface of the combiner unit 4 is incident on the pupil 6.

The LCD 2, the flat glass 13, and the relay optical system 14 are mounted on one housing, and can be mounted on and removed from the vine 1 of the glasses. In this way, since the lens 3 of the eyeglasses and the outside object beam guide means can and another, regardless of the degree of myopia or hyperopia, can use a common image display device.

FIG. 6 is a diagram showing an example of a method of manufacturing the external object light guiding means used in the present invention. First, a metal body is prepared (a), and a mold having a shape in which the reflection surface of the combiner portion is inverted on the surface is manufactured by precision cutting (b). Then, this mold is pressed against a substrate material constituting an optical component such as a lens (c), and a base material having a shape of a reflection surface of a combiner portion is formed on the surface, and a semi-permeable membrane is formed on a portion to be a reflection surface. Is deposited (d).

Similarly, using the same substrate material,
A substrate material having a surface shape so as to be in close contact with the base material shown in (d) is manufactured (a semi-permeable film is not deposited), and the two are overlapped and joined (e). At this time,
After filling the reflective surface shape of the base material with an adhesive such as a photocurable resin, the base material may be joined to the same substrate material having a planar shape. Thereafter, the bonded substrate material is polished to complete the external object light guiding means having the desired curvature on the front and back surfaces (f).

In some embodiments of the present invention, the combiner is installed inside the lens of the spectacles. At this time, there is a chromatic aberration as a problem to be considered. When the light from the LCD has several wavelengths, it is better to reduce the distance between the reflecting surface of the combiner and the surface of the lens on the pupil side. Therefore, the problem of chromatic aberration is reduced by making the distance between the reflecting surface of the combiner portion and the surface of the lens on the pupil side smaller than the distance between the reflecting surface of the combiner portion and the object-side surface of the lens.

[0042] In the case where the angle between the plane of the reflecting surface and the pupil side of the lens of the combiner unit may be very small, it got to form a reflective surface of the combiner unit to a surface of the pupil side of the lens It doesn't matter.

[0043]

As described above, according to the present invention,
It is possible to obtain a see-through type image display device which can be configured with a small and thin optical system, can be applied to actual spectacle lenses having various curved surface shapes, and can form a good image with a wide angle of view.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an image display device as an example of an embodiment of the present invention, which is formed in an eyeglass-like shape.

2 is a diagram showing a main part of an example of embodiment shown in FIG.

3 is a diagram showing an example of a schematic of another embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a mounted state of a video display device according to another embodiment of the present invention as viewed from above.

FIG. 5 is a diagram showing an outline of an example of another embodiment of the present invention in which the glasses and the image display device are separated.

FIG. 6 is a diagram showing an example of a method of manufacturing the external object light guide means used in the present invention.

FIG. 7

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... vine part, 2 ... LCD, 3 ... lens, 4 ... Combiner part, 5 ... Frame, 6 ... Pupil, 7 ... Light from the outside, 8 ... Reflection type Fresnel lens, 9 ... Reflection mirror, 10 ... Intermediate image, 11
... Lens, 12 ... Reflection mirror, 13 ... Plate glass, 14 ... Relay optical system

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02C 7/14 G02C 7/14 G02F 1/13 505 G02F 1/13 505 H04N 5/64 511 H04N 5/64 511A

Claims (8)

[Claims] 1. A are arranged in front of the eyes of the observer, the indicated A video display device for providing the viewer with an image of the image and the outside object, a combiner unit having a reflecting surface, the observer with light from the outside comprising a external object light guiding means for guiding the eye, the formed and image forming means for guiding the external object light guiding means a video, the combiner section, the reflecting surface is formed by a plurality of discontinuous surfaces An image display device having a function of reflecting image light emitted from the image forming means and guiding the image light to an observer's pupil. 2. A video display apparatus according to claim 1, image light reflected by the combiner unit, viewed from the observer's pupil, the image on the external object side of the external object beam guide means A video display device for forming a virtual image of the image. 3. A video display apparatus according to claim 1, the image forming means serves to form an intermediate in the real image with itself and the combiner section, image light reflected by the combiner unit An image display device for forming a virtual image of the real image on an external object side of the external object light guide means when viewed from an observer's pupil. 4. The image display device according to claim 2, wherein the virtual image formed by the combiner unit is an image formed on a surface of the image forming unit, or an image formed by the image forming unit. A video display device, wherein a shape of a reflection surface of the combiner is selected so that a real image formed in the middle of the combiner is enlarged or reduced. 5. The either one of claims 2 4 1
Item, the image formed on the surface of the image forming means, or emitted from a real image formed between the image forming means and the combiner section and reflected by the combiner section And an optical path length of a principal ray guided to an observer's pupil is substantially the same for principal rays emitted from any part of the image or the real image. 6. One of claims 1 to 5
Item 4. The image display device according to Item 1, wherein the external object light guiding means is a lens. 7. One of claims 1 to 6
A video display apparatus according to claim, the video display apparatus characterized by being formed in a spectacle shape. 8. One of claims 1 to 6
The video display device according to the above item, wherein the video display device has a structure that can be attached to and detached from eyeglasses.