JP3103986B2 - Direct-view image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a 3-order by using a laser beam
The present invention relates to a direct-view image display device that displays an original image .

[0002]

2. Description of the Related Art Various technologies for displaying an image giving a three-dimensional effect or a three-dimensional image are known as "three-dimensional display" (Sangyo Tosho) (Chihiro Masuda) and "Trial development of three-dimensional display so far and future. Of the Future ”(“ Video Information ”1985/8). Gives a three-dimensional feeling
An image referred to as an obtained image or a three-dimensional image is classified as follows. (1) Binocular type. In terms of the information amount, it is the information amount for the left and right two eyes. It is called a stereoscopic image. (2) An image in which a reproduced image of an object appears in a space. In other words, if you move the viewpoint, you can see the side that wraps around, and the amount of information is for multiple eyes or more. It is called a three-dimensional image in a narrow sense. (3) Those utilizing psychological effects .

[0003] Factors for recognizing an image as a three-dimensional image are as follows.
As shown in Table 1, in monocular vision, focus adjustment, image size, motion parallax, and visual field are factors. In binocular vision, binocular convergence and binocular disparity are factors. This is described, for example, in the Journal of the Institute of Television Engineers of Japan, Vol. 43, no. 8
(1989).

The conventional technique disclosed in the above-mentioned documents and the like
The classification of the three-dimensional image perception factors of the three- dimensional image display device is as shown in Table 2.

[0005] Patents relating to stereoscopic images are also disclosed in, for example, JP-A-64-42998 and JP-A-62-77794.
JP-A-56-69612, U.S. Pat.
799, 103, etc.

[0006]

However, in the apparatus described in, for example, Japanese Patent Application Laid-Open No. Sho 64-42998, the luminous body must emit light with divergent light, and both high resolution and sufficient brightness are required. Is difficult.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. Sho 62-77794, a varifocal lens array having a fine shape must be prepared, and its realization is difficult.

Further, the apparatus described in Japanese Patent Application Laid-Open No. 56-69612 is of a moving screen type, so that it is difficult to move the screen at a high speed, and the deterioration of the image quality due to speckle noise is avoided. There are also issues that cannot be met.

Further, the apparatus described in US Pat. No. 4,799,103 employs a variable focus mirror system, so that a so-called phantom image phenomenon occurs in which an object being displayed can be seen inside or on the opposite side, and raster scanning is performed. It is not suitable for displaying an image of an image signal based on a television broadcast or the like being performed.

Furthermore, what can be said in common with any of these devices is that since a three-dimensional image is displayed as a real image, not only the configuration becomes complicated, but also the problem is that the device becomes large.

The present invention has been made in view of such a situation, and has an object to enable a three-dimensional image to be displayed with a simple configuration and a small device.

[0012]

According to the present invention, there is provided a direct-view image display apparatus comprising: a light source for emitting laser light; a modulating means for optically modulating a laser light emitted from the light source or the light source with a video signal; Depending on the corresponding depth signal,
A variable focus optical system for changing the focus of the laser light modulated by the adjusting means, a scanning means for scanning the laser light with a scanning signal, and a projection optical system for forming an image of the scanned laser light on a retina of an eye. It is characterized by the following.

[0013]

In the direct-view image display device having the above-mentioned structure, the variable focus optical system controls the depth signal corresponding to the video signal.
The focus is changed accordingly and the laser light scanned by the scanning means is directly imaged on the retina of the eye. Therefore, a three-dimensional image can be displayed by a small device having a simple configuration.

[0014]

FIG. 2 shows a basic configuration of an embodiment of a direct-view image display apparatus according to the present invention. The direct-view image display device of this embodiment includes a laser light source 61 for generating laser light, a light modulator 62 for optically modulating laser light in accordance with a video signal supplied from a video signal supply circuit 63, and a depth signal supply circuit. A variable focus optical system 64 for changing the focal point according to the depth signal supplied from the scanning signal supply circuit 65;
A horizontal scanning device 68 for scanning the laser beam in the horizontal direction in accordance with the scanning signal supplied from 7, and a vertical scanning for the laser beam.
It comprises a scanning device system 66 having a vertical scanning device 69 and a projection optical system 70 for projecting a laser beam to the eye 71.

In the embodiment of FIG. 2A, the scanning device system 66 is
After scanning in the horizontal direction in the horizontal scanning unit 68, a vertical
While the scanning device 69 is configured to scan in the vertical direction, in the embodiment of FIG.
After being scanned in the vertical direction by the vertical scanning device 69, water
The flat scanning device 68 scans in the horizontal direction. That is, only the order of scanning is different, and other configurations are basically the same.

In the embodiment shown in FIG. 2, the variable focus optical system 64 is inserted between the light modulator 62 and the scanning device system 66. This variable focus optical system 64 is shown in FIG. 3, for example. It is also possible to insert and arrange inside the scanning device system 66 as described above. In the embodiment of FIG. 3 (a), the horizontal
The laser beam scanned in the horizontal direction by the scanning device 68 is
The data is input to the vertical scanning device 69 via the variable focus optical system 64. In the embodiment shown in FIG. 3B, the laser beam scanned in the vertical direction by the vertical scanning device 69 is applied to the horizontal scanning device via the variable focus optical system 64.
The data is input to the device 68.

Further, the variable focus optical system 64 can be arranged inside the projection optical system 70 as shown in FIG. In the embodiment of FIG. 4 (a), the scanning instrumentation 置系 66
Horizontal scanning device 68, while being arranged in order of the vertical scanning unit 69, in the embodiment of FIG. 4 (b), vertical
Scanning device 69, they are arranged in the order of horizontal scanning equipment 68.

[0018] As shown in FIGS. 2 to 4, but variable focus optical system 64 is capable of inserting disposed at various locations, a light modulation device 62 as shown in FIG. 2 scanner system 66
In this case, it is possible to obtain the advantage that the diameter of the lens of the variable focal length optical system can be small and the size of the image does not change even if the focal length changes.

FIG. 1 shows a more specific configuration of the embodiment shown in FIG. In this embodiment, the laser light source 61 is constituted by the RGB laser 1.
The light modulator 62 is an acousto-optic modulator (AOM) 4R, 4R.
G, 4B, and the video signal supply circuit 63 corresponds to the video signal supply circuits 5R, 5G, 5B, respectively. Variable focus optical system 64 is constituted by a variable focus lens 9, the depth signal supplying circuit 65 corresponds the depth signal supplying circuit 10, also, the horizontal scanning unit 68, Porigonmi
This is constituted by a lens 11. The vertical scanning device 69
It is constituted by a galvanometer mirror 12. The scanning signal supply circuit 67 corresponds to the scanning signal supply circuit 13.
Further, the projection optical system 70 includes the relay lenses 14 and 15, and the eye 71 corresponds to the eye 16.

Next, the operation of the embodiment shown in FIG. 1 will be described. When laser light having red (R), green (G), and blue (B) wavelengths is output from the RGB laser 1, the dichroic mirror 2R reflects a red wavelength component from the laser light, and outputs green and blue light. Permeate the components. The dichroic mirror 2G reflects a green component of the incident laser light and transmits a blue component. The blue component laser light is reflected by the mirror 2B. Thus, R, G,
After the laser light of each wavelength B is adjusted by the lenses 3R, 3G, and 3B into a beam shape suitable for the modulation operation of the acousto-optic modulators 4R, 4G, and 4B, the corresponding acousto-optic modulators 4R, 4G, and 4B respectively. Is input to These acousto-optic modulators 4R, 4G, 4B are supplied with red, green, or blue video signals from video signal supply circuits 5R, 5G, 5B, respectively. Acousto-optic modulators 4R, 4G, 4
B optically modulates the input laser light in accordance with the supplied video signal.

The laser beams emitted from the acousto-optic modulators 4R, 4G, 4B are adjusted into beams by the lenses 6R, 6G, 6B, respectively, and then enter the dichroic mirrors 7R, 7G or the mirror 7B. And reflected there. The blue component laser light reflected by the mirror 7B is
The light enters the dichroic mirror 7G, passes therethrough, and is synthesized with the green component laser light supplied from the lens 6G. The laser light of the blue and green components is incident on the dichroic mirror 7R, and is combined with the laser light of the red component supplied from the lens 6R. In this way, the laser light that has been returned to the original one beam is reflected by the mirror 8 and is incident on the varifocal lens 9. The focal length of the varifocal lens 9 changes according to the depth signal supplied from the depth signal supply circuit 10.

The laser light emitted from the variable focus lens 9 enters the polygon mirror 11 and is scanned in the horizontal direction in accordance with a horizontal scanning signal supplied from a scanning signal supply circuit 13. The laser light reflected by the polygon mirror 11 is incident on the galvano mirror 12 and is scanned in the vertical scanning direction according to the vertical scanning signal supplied from the scanning signal supply circuit 13. In this manner, the laser light scanned in the horizontal and vertical directions passes through the lenses 14 and 15.
Through the eye 16.

Next, the operation principle of FIG. 1 will be described with reference to FIGS. For convenience of explanation, the lens 14,
The projection optical system 70 having an ideal lens 21,
Thereby constitute an afocal optical system. That is, the ideal lenses 21 and 22 share a focal plane 23 as shown in FIG. Now, assuming that the variable focus lens 9 is not inserted, a real image is formed on the focal plane 23 and the real image is projected on the fundus 24 of the eye 16. Therefore, as shown in FIG. 5B, all the scanned laser beams form an image on the fundus oculi 24, and the eye 16 sees a virtual image at infinity.

[0024] In contrast, insertion of variable focus lens 9 as in the embodiment of FIG 1, the laser light output from the ideal lens 21 as shown in FIG. 6 (a), the variable focus lens
Since the focal length of the lens 9 changes according to the depth signal,
An image is not formed on the focal plane 23 but a real image is formed on the curved surface 25. As a result, all of the laser light incident on the eye 16 via the ideal lens 22 does not form an image on the fundus 24, and only the laser light corresponding to the distance at which the eye 16 is focused is on the fundus 24. Will be imaged. Therefore,
At this time, the virtual image viewed from the eye 16 is an image at a position indicated by the curved surface 26 as shown in FIG.
That is, the light emitted from the curved surface 26 appears to be incident on the eye 16.

[0025] It is found, in response to the focusing function of the human eye as actually see a three-dimensional object, the focus differences occur in the vicinity of those and a distant, to obtain a stereoscopic effect Can be.

In the above, the embodiment in the case of observing the image with a single eye has been described. However, in the case of observing the image with both eyes, the embodiment can be configured as shown in FIG.

In the case of this embodiment, the RGB laser 31
The emitted laser light is split by a beam splitter (half prism) 32 into a right-eye laser light and a left-eye laser light. The laser light for the right eye is emitted by dichroic mirrors 33aR, 33aG, and mirror 33aB.
Each of the lenses 34aR and 34a is divided into three components of RGB.
G, after the shape of the beam is adjusted by 34ab, acousto-optic modulator 35aR, 35aG, enter each 35aB
It is elevation. These acousto-optic modulators 35aR, 35a
G and 35aB include video signal supply circuits 49aR and 49a.
R, G, and B video signals are supplied from G and 49aB, respectively, and the incident laser light is optically modulated in accordance with these video signals. Acousto-optic modulators 35aR, 35
The laser light emitted from aG and 35aB is
After the beam shape is adjusted by aR, 36aG and 36aB, mirror 37aR and dichroic mirror 37a
After being combined into one laser beam again by G and 37aB, the laser beam is incident on the varifocal lens 38a. The varifocal lens 38a changes its focal length in response to the right-eye depth signal emitted by the depth signal generation circuit 39a.
The laser light emitted from the varifocal lens 38a enters the polarization beam splitter 41 and passes therethrough.

On the other hand, the laser light for the left eye split by the beam splitter 32 is applied to a dichroic mirror 33b.
The laser beam is divided into three RGB laser beams by R, 33bG and mirror 33bB. These laser beams are adjusted to a predetermined cross-sectional shape by lenses 34bR, 34bG, 34bB, and then acousto-optic modulators 35bR, 35bG, 3
They are respectively incident on 5bb. These acousto-optic modulators 35bR, 35bG, 35bB are connected to the video signal supply circuit 4
The incident laser light is modulated in accordance with the RGB video signals supplied from 9bR, 49bG, and 49bB. The light-modulated laser light is supplied to lenses 36bR, 36bG, 3
After its cross-sectional shape is adjusted by 6bB, it is combined into one laser beam by dichroic mirrors 37bR and 37bG and mirror 37bB.

This one laser beam is applied to the varifocal lens 3
8b. The focal length of the varifocal lens 38b is changed in accordance with the left-eye depth signal supplied from the depth signal supply circuit 39b. Variable focus lens 38
The laser beam emitted from b is incident <br/> to 1/2-wavelength plate 40. The laser light emitted from the RGB laser 31 is
It is in a linear polarization state, and its polarization plane is rotated by 90 degrees by transmitting through the half-wave plate 40. As a result, the laser light incident from the varifocal lens 38a passes through the polarization beam splitter 41, but the laser light incident from the varifocal lens 38b via the half-wave plate 40 is reflected by the polarization beam splitter 41. Then, it is combined with the laser light incident from the variable focus lens 38a.

The laser beam emitted from the polarizing beam splitter 41 is incident on a polygon mirror 42 and is scanned in the horizontal direction in accordance with a horizontal scanning signal supplied from a scanning signal supply circuit 50. The laser light reflected by the polygon mirror 42 is incident on the galvano mirror 43 and is scanned in the vertical scanning direction according to the vertical scanning signal emitted from the scanning signal supply circuit 50.

[0031] In this way, the laser beam scanned in the horizontal and vertical scanning direction is incident on the polarization beam splitter 46 through the lenses 44 and 45. As described above, the directions of the polarization planes of the laser light for the right eye and the laser light for the left eye are different from each other by 90 degrees. Accordingly, the laser light for the right eye passes through the polarizing beam splitter 46, enters the mirror 47a, is reflected there, and enters the right eye 48a. The laser light for the left eye is reflected by the polarization beam splitter 46, further reflected by the mirror 47b, and made incident on the left eye 48b.

Thus, in the embodiment of FIG.
A three-dimensional image can be observed with both eyes.

In the embodiment shown in FIG. 1, a three-dimensional image is viewed only by the function of adjusting the focus of the human eye. However, in the embodiment of FIG. 7, in addition to the focus adjustment function, a three-dimensional image can be observed by binocular parallax and convergence.

In each of the embodiments, a virtual image is observed without passing through a screen or the like. Therefore, when the virtual images are observed according to the classification in Table 2, the images are classified into aerial image display. .

The variable focus lenses 9 and 38 described above
a and 38b can be constituted by a liquid crystal lens or an EO lens. In addition, a one-dimensional variable focus cylindrical lens can be used in combination. Of course, a combination lens with an ordinary lens may be used. For the liquid crystal lens, for example, "Research on liquid crystal lens"
(“Optics,” Vol. 18, No. 12, December 1989). Regarding the EO lens, “Prototype EO lens using EO material and transparent electrode” (“OplusE” (1)
March 990)).

The depth signal given to the variable focus lens includes aberrations such as spherical aberration and field curvature of the lens of the optical system.
It is also possible to make corrections based on information relating to image distortion and focus adjustment (diopter adjustment) due to differences in the visual acuity of the observer.

As the variable focus optical system, it is possible to use a variable focus mirror in addition to the variable focus lens.

In the above system, the raster scan system has been described as an embodiment, but the present invention can be applied to a vector system.

Further, in the above embodiment, the laser light
Source 61 is red, green, to the wavelength or Ranaru RGB laser 1 of the blue
The laser that outputs one wavelength
It is also possible to display a single color image by using the light source
Possible Ru Der. The wavelength of the laser light source is red, green, and blue.
Not limited to this, the color reproduction range can be increased by using multiple wavelengths.
Can be spread.

Further, in the above embodiment, the laser
Although the light source 61 and the light modulation device 62 are provided separately,
Use a laser source that can be directly modulated, such as a conductor laser
It is also possible to combine those configurations into one
It is.

[0041]

As described above, according to the direct-view image display apparatus of the present invention, the depth corresponding to the video signal is obtained by the variable focus optical system.
Since the focal point is changed according to the going signal and the laser beam scanned by the scanning means is directly imaged on the retina of the eye, the following effects are obtained. (1) The configuration is simple. (2) The size of the three-dimensional image is determined only by the viewing angle up to the previous stage of the projection optical system, and there is no need to increase the size of the apparatus even when displaying a large three-dimensional image. (3) It is possible to display current television systems such as NTSC, PAL, SECAM, and HDTV. (4) Compared with other depth sampling type displays, a high-quality three-dimensional image can be obtained without generating a phantom image. (5) If a variable-focus optical system capable of high-speed driving is used, a three-dimensional television signal can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a more specific configuration of the embodiment shown in FIG.

FIG. 2 is a block diagram illustrating a configuration of an embodiment of a direct-view image display device according to the present invention.

FIG. 3 is a block diagram showing the configuration of another embodiment of the direct-view image display device of the present invention.

FIG. 4 is a block diagram showing the configuration of still another embodiment of the direct-view image display device of the present invention.

FIG. 5 is a diagram for explaining the operation of the embodiment in FIG. 1;

FIG. 6 is a diagram for explaining the operation of the embodiment in FIG. 1;

FIG. 7 is a diagram showing a configuration of an embodiment obtained by developing the embodiment of FIG. 1 into a binocular system.

[Explanation of symbols]

Reference Signs List 1 RGB laser 4R, 4G, 4B Acousto-optic modulator 5R, 5G, 5B Video signal supply circuit 9 Variable focus lens 10 Depth signal supply circuit 11 Polygon mirror 12 Galvano mirror 13 Scanning signal supply circuit 14, 15 lens 16 eyes

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-90153 (JP, A) JP-A-2-251927 (JP, A) JP-A-3-2790 (JP, A) JP-A 62-90 77794 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G09G 3/02 G02B 26/10 H04N 13/04

Claims (1)

(57) [Claims] A light source that emits laser light; a modulating unit that optically modulates the light source or the laser light emitted from the light source with a video signal; and a modulation unit that responds to a depth signal corresponding to the video signal.
A variable focus optical system for changing the focus of the laser light modulated by the adjusting means; a scanning means for scanning the laser light with a scanning signal; and a projection optical system for forming an image of the scanned laser light on a retina of an eye. And a direct-view image display device.