JP3460671B2 - Three-dimensional display method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional display method and device, and more particularly to a three-dimensional display method and device capable of electronically reproducing a three-dimensional stereoscopic image with a reduced amount of information.

[0002]

2. Description of the Related Art A liquid crystal shutter spectacle system shown in FIG. 29 is well known as a conventional device which is electrically rewritable, has a small amount of information, and enables stereoscopic display of moving images.
The principle of the liquid crystal shutter glasses system will be described below. In this liquid crystal shutter glasses system, a camera (6
02, 603), the three-dimensional object 601 is photographed from different directions, and an image (parallax image) obtained by photographing the three-dimensional object 601 from different directions is generated. Camera (602, 603)
The video image captured by the video signal conversion device 604 is combined into one video signal, and the two-dimensional display device (for example,
CRT display device) 605. The observer 607 is
Two-dimensional display device 605 wearing liquid crystal shutter glasses 606
Observe the image of.

Here, the two-dimensional display device 605 is the camera 6
03, the liquid crystal shutter glasses 60 are displayed.
6 has a non-transparent state on the left side and a transparent state on the right side.
When the two-dimensional display device 605 is displaying the image of the camera 602, the left side of the liquid crystal shutter glasses 606 is in a transparent state,
The right side is non-transparent. When the above operations are switched at high speed, a parallax image is felt by both eyes due to the afterimage effect of the eyes. Therefore, stereoscopic viewing by binocular parallax is possible. Further, as a conventional device which is electrically rewritable, has a small amount of information, and enables stereoscopic display of a moving image, FIG.
The volume type method shown in (1) is also proposed. Hereinafter, the principle of this volume type system will be described. In this volume type system, as shown in FIG. 30B, a three-dimensional object 611 is sampled in the depth direction when viewed from an observer to form a two-dimensional image group 612, and the two-dimensional image group 612 is Figure 30
Using the volumetric three-dimensional display device 613 shown in (a), for example, the three-dimensional redevelopment 614 is reconfigured by arranging again in the depth direction in time division.

[0004]

However, since the liquid crystal shutter glasses 606 shown in FIG. 29 requires the liquid crystal shutter glasses 606, it is very unnatural in the case of a video conference. was there. Also,
Among the physiological factors of stereoscopic vision, there is a great contradiction between binocular parallax, vergence and focus adjustment. That is, in the liquid crystal shutter spectacle system shown in FIG. 29, the binocular parallax and the convergence can be almost satisfied, but since the focusing surface is on the display surface, this contradiction causes a problem of eye strain.
Further, in the volume type method shown in FIG. 30, since the depth position of the three-dimensional object 611 to be reproduced is close to and sandwiched by the surface on which an image is actually displayed, the liquid crystal shutter shown in FIG. Unlike the spectacle method, it is possible to suppress the contradiction between binocular parallax, convergence, and focus adjustment. However, in this volume type method, since the positions are discrete in the depth direction, it is difficult to reproduce a three-dimensional object at an intermediate position or a three-dimensional object that greatly changes in the depth direction. there were.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a three-dimensional display method and apparatus capable of displaying a moving image without using glasses. It is in. Another object of the present invention is to provide a three-dimensional display method and device capable of suppressing a contradiction between physiological factors of stereoscopic vision. Another object of the present invention is to provide an electrically rewritable three-dimensional display method and apparatus. The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0006]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows. That is, the present invention generates a two-dimensional image obtained by projecting a display target object in the line-of-sight direction of the observer on a plurality of display surfaces at different depth positions as viewed from the observer, and A three-dimensional stereoscopic image is displayed by displaying a two-dimensional image on a plurality of display surfaces at different depth positions when viewed from the observer, and changing the brightness of the displayed two-dimensional image independently for each display surface. A three-dimensional display method for generating an image, wherein the transmittance of a two-dimensional image displayed on each display surface is changed independently for each display surface, and the two-dimensional image displayed on each display surface is changed. The feature is that the brightness of the three-dimensional image is changed independently.

Further, according to the present invention, a two-dimensional image obtained by projecting a display target object from a line-of-sight direction of the observer on a plurality of display surfaces at different depth positions from the observer's side is generated. The two-dimensional image is displayed on a plurality of display surfaces at different depth positions viewed from the observer,
A three-dimensional display method in which the brightness of the displayed two-dimensional image is changed independently for each of the display surfaces to generate a three-dimensional stereoscopic image. A three-dimensional display method characterized in that the polarization direction is changed independently for each display surface, and the brightness of the two-dimensional image displayed on each display surface is changed independently.

Further, according to the present invention, when the display target object is an object displayed at a depth position close to the observer, the display target object is displayed on the display surface close to the observer among the plurality of display surfaces. The transmittance of the two-dimensional image is low, the transmittance of the two-dimensional image displayed on the display surface far from the observer is high, and the display target object is displayed at a depth position far from the observer. In the case of an object, the two-dimensional image displayed on the display surface far from the viewer by increasing the transmittance of the two-dimensional image displayed on the display surface close to the viewer among the plurality of display surfaces. It is characterized by lowering the transparency of.

Further, according to the present invention, the two-dimensional images are displayed on the plurality of display surfaces so that the two-dimensional images overlap each other when viewed from one point on a line connecting the right eye and the left eye of the observer, In addition, the overall brightness seen by the observer is set to be equal to the brightness of the original display target object. Further, the present invention displays the two-dimensional image on the plurality of display surfaces so that the two-dimensional image overlaps when viewed from one point on a line connecting the right eye and the left eye of the observer, and a display target. When the depth position of the object is far from the observer, the transmittance of the two-dimensional image is higher than that when the depth position is close to the observer.

Further, the present invention is characterized in that one point on a line connecting the right eye and the left eye of the observer is one point between the right eye and the left eye. Further, the present invention is characterized in that a point on a line connecting the right eye and the left eye of the observer is a center point of the right eye and the left eye. In addition, the present invention, the two-dimensional image displayed on each of the display surface, so as to be overlapped when viewed from one point on the line connecting the right eye and the left eye of the observer, left and right when viewed from the observer. It is characterized by adding deformation of enlargement / reduction in the direction. Further, the present invention, the depth position between the display surfaces for displaying the two-dimensional image, a plurality of two-dimensional images displayed on those display surfaces for the same display target object, the right eye of the observer. It is characterized in that it is a range having a common region when viewed from the left eye position with a single eye.

Further, according to the present invention, the depth position between the display surfaces for displaying the two-dimensional images is determined by the observer when a plurality of two-dimensional images displayed on the display objects are displayed on the same display target object. It is characterized in that the focus on the depth position of the display target object is within a range in which the image is less blurred than the focus on the plurality of display surfaces. Also,
The present invention is characterized in that a three-dimensional moving image is displayed by sequentially switching the two-dimensional images according to a temporal change. Further, the present invention is the case where the two-dimensional image includes a plurality of object images moving in the depth direction, and when the moving direction of the object is a direction approaching the observer, switching of the two-dimensional image. In synchronism with the above, the transmittance of the object image displayed on the display surface closer to the viewer among the plurality of display surfaces is sequentially decreased, and the transmittance of the object image displayed on the display surface far from the viewer. Sequentially, and when the moving direction of the object is a direction away from the observer, in synchronization with the switching of the two-dimensional image, the display surface close to the observer of the plurality of display surfaces. The transmittance of the object image displayed on the display is sequentially increased, and the transmittance of the object image displayed on the display surface far from the observer is sequentially decreased .

The present invention is also a three-dimensional display device, wherein an object to be displayed is projected from a line-of-sight direction of the observer on a plurality of display surfaces at different depth positions as seen by the observer. First means for generating a two-dimensional image, and a plurality of transmissive display devices arranged at different depth positions as viewed by the observer and displaying the two-dimensional images generated by the first means, respectively. A second means for independently changing the transmittance of the two-dimensional image generated by the first means and displayed on each of the transmissive display devices for each of the transmissive display devices. And

The present invention further includes a first light source disposed behind the plurality of transmissive display devices as viewed by the observer, wherein each transmissive display device is arranged from the first light source. It is characterized by changing the light transmittance of the. Further, the present invention has at least one second light source arranged in front of the plurality of transmissive display devices, and each transmissive display device includes at least one second light source. It is characterized in that the degree of light scattering or the rate of change is changed, and the degree of light transmitted from a transmission type display device located behind is changed.

According to the present invention, the plurality of transmissive display devices change the transmissivity of red in the light from the light source and transmit almost all of the green and blue lights, and the transmissive display device of green. It is characterized by having a device that changes the degree of light and transmits almost all of the red and blue light, and a device that changes the degree of transmission of blue and that transmits almost all of the red and green light. Further, the present invention is characterized in that the plurality of transmissive display devices have a uniform display device in which the transmittance of light from a light source is changed uniformly over substantially the entire visible light range, and a luminescent color.
It is characterized in that it includes a light source that changes rapidly in red, green, and blue in a time division manner, and a synchronizing device that synchronizes the color change of the light source and the display of the uniform display device.

Further, according to the present invention, the plurality of transmission type display devices include a plurality of polarization changing devices capable of changing a polarization direction of light, and further a polarizing plate sandwiching all or a part of the plurality of polarization changing devices. It is characterized by having. In the present invention, the plurality of transmissive display devices change the polarization direction of red in the light from the light source, and the device in which the polarization directions of green and blue hardly change, and change the polarization direction of green. However, it includes a device that hardly changes the polarization directions of red and blue, and a device that changes the polarization directions of blue and hardly changes the polarization directions of red and green. It is characterized by having a plate.

Further, the present invention is characterized in that each of the transmission type display devices has a polarization variable device and an emission side polarization plate provided on the emission side from the polarization variable device.
Further, the present invention is characterized by further including an incident side polarization plate provided on the incident side from the polarization variable device. In the invention, at least one of the plurality of transmissive display devices is a twisted nematic liquid crystal display, an in-plane liquid crystal display, a homogeneous liquid crystal display, a ferroelectric liquid crystal display, a guest-host liquid crystal display, It is characterized by being a polymer dispersed liquid crystal display or a holographic polymer dispersed liquid crystal display.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for explaining the embodiments, the same reference numerals are given to those having the same function, and the repeated description thereof will be omitted. It should be noted that in the following embodiments, a case will be described in which a three-dimensional object to be presented is mainly displayed as a two-dimensional image on two transmissive display devices, but the same effect can be obtained by using two or more transmissive display devices. It is clear that can be expected. [First Embodiment] FIGS. 1 to 6 show a first embodiment of the present invention.
FIG. 3 is a diagram for explaining the principle of the three-dimensional display device of FIG. In the present embodiment, as shown in FIG. 1, a plurality of transmissive display devices, for example, transmissive display devices (101, 102) (transmissive display device 101 is a transmissive display device 102 is provided on the front surface of observer 100. (Closer to the observer 100), various optical elements, and the light source 110 are used to construct the optical system 103.
As the transmissive display device (101, 102), for example, a twisted nematic liquid crystal display,
A plain type liquid crystal display, a homogeneous type liquid crystal display, a ferroelectric liquid crystal display, a guest-host type liquid crystal display, a polymer dispersed liquid crystal display, a holographic polymer dispersed liquid crystal display, or a combination thereof is used. As the optical element, for example, a lens, a total reflection mirror, a partial reflection mirror, a curved mirror, a prism, a polarizing element, a wave plate, or the like is used. In the present embodiment, as an example, the case where light source 110 is arranged at the rearmost side when viewed from observer 100 is shown.

Next, as shown in FIG. 2, an image of a three-dimensional object 104 to be presented to the observer 100 viewed from the observer 100 onto the transmissive display device (101, 102) (hereinafter, referred to as " 2D image (1) which is a 2D image.
05, 106) is generated. As a method of generating this 2D image, for example, a method of using a two-dimensional image of the three-dimensional object 104 taken by a camera from the line-of-sight direction of the observer 100 or a method of combining two-dimensional images taken from different directions is used. There are various methods such as a method or a method using a computer graphic synthesis technique or modeling. The 2D image (105, 106) is shown in FIG.
A 2D image (107, 108) is displayed on each of the transmissive display device 101 and the transmissive display device 102 so as to overlap with each other when viewed from a point on the line connecting the right eye and the left eye of the observer 100. This is, for example, a 2D image (105, 10
This can be achieved by controlling the center position and the position of the center of gravity of each of 6) and the enlargement / reduction ratio of each image. The image viewed by the observer 100 on the apparatus having the above-described configuration is a 2D image 1
It is generated by the light that transmits 08 and further transmits the 2D image 107.

An important point in the present invention is that the brightness of the image viewed by the observer 100 is kept constant so as to be the same as the brightness of the three-dimensional object 104 to be displayed, while the 2D image is displayed.
This is to change the depth position of the image that the observer 100 feels by changing the distribution of the transmittance of the image 107 and the 2D image 108. An example of how to change it will be described below. Since the drawing is a black and white drawing, the one with lower transparency is shown darker for easier understanding. For example, when the three-dimensional object 104 is on the transmissive display device 101, as shown in FIG. 3, the transmissivity on the transmissive display device 101 is calculated as follows: the brightness of the 2D image 107 is the brightness of the three-dimensional object 104. And the transmittance of the portion of the 2D image 108 on the transmissive display device 102 is set to, for example, the maximum value of the transmissive display device 102. Next, for example, when the three-dimensional object 104 is a little farther from the observer 100 and is slightly closer to the transmissive display device 102 than the transmissive display device 101, as shown in FIG. The transmittance of the portion of the 2D image 107 on the display device 101 is slightly increased, and the transmittance of the portion of the 2D image 108 on the transmission display device 102 is slightly decreased.

Further, for example, the three-dimensional object 104 is moved further away from the observer 100, and the transmissive display device 101 is displayed.
In the case of a position further closer to the transmissive display device 102 side, as shown in FIG. 5, the transmissivity of the portion of the 2D image 107 on the transmissive display device 101 is further increased, and the transmissive display device is displayed. The transmittance of the portion of the 2D image 108 on 102 is further reduced. Finally, for example, the three-dimensional object 104
6 is on the transmissive display device 102, the transmissivity on the transmissive display device 102 is set so that the brightness of the 2D image 108 is equal to the brightness of the three-dimensional object 104, as shown in FIG. 2D image 107 on the transmissive display device 101.
The transmissivity of the portion is set to, for example, the maximum value of the transmissive display device 101. By displaying in this manner, even if a 2D image (107, 108) is displayed due to a physiological or psychological factor or illusion of a person, it is as if the transmissive display device ( 101, 102)
It is felt that the three-dimensional object 104 is located in the middle of.

That is, for example, a transmissive display device (101,
When the transmissivity of the 2D image portions (107, 108) of (102) is set to be substantially the same, the transmissive display device (10
3D object 10 near the middle of the depth position of
It feels like there is a 4. In the present embodiment, when the 2D image is displayed so as to overlap with each other when viewed from a point on the line connecting the right eye and the left eye of the observer 100, in particular, the right eye and the left eye of the observer 100 are When one point between the right eye and the left eye is used as one point on the connecting line, the three-dimensional perception of the three-dimensional perception at the intermediate position of the plurality of surfaces (that is, the arrangement positions of the transmissive display devices (101, 102)) is performed. Greater credibility for the benefits (briefly, it works for many people, or in many cases). Furthermore, if the center positions of the left and right eyes of the observer 100 are used as the one point,
It becomes easier to obtain the effect, and in the left and right eyes,
For example, it has an advantage that the size of a double image generated from a transmission two-dimensional image displayed on the transmission type display device (101, 102) can be reduced.

[0022] Moreover, before describing the 2D of image observer 100
To scale the left-right direction of the size as seen from the front
As described above, the 2D image is taken from the right eye and the left eye of the observer 100.
Display so that they overlap when viewed from one point on the line connecting the eyes
Not only it is effective, it is also effective to vary the depth to be perceived. Further, the depth distance between the surfaces displaying the transmission two-dimensional image (that is, the distance between the transmission type display device 101 and the transmission type display device 102) for obtaining the above-mentioned effect is the same as the display target object ( Three-dimensional object 104)
, The two-dimensional images (2
A D-image) is a range having a common region when viewed from the positions of the right eye and the left eye of the observer 100 with a single eye. That is, in the state where there is no common region, this effect disappears and the observer 100 feels that the surface is separated in the depth direction.

In the present embodiment, unlike the conventional method shown in FIG. 29, there are at least two surfaces for actually displaying an image with the illusionary position sandwiched therebetween. It is considered that the contradiction between parallax and vergence and focus adjustment can be greatly suppressed, and eye strain and the like can be suppressed. In addition, the focus adjustment itself means that the observer 100 views two or more surfaces at the same time, and thus positions both images so that they can be viewed with the least blurring, which is a drawback of the conventional method. Can be greatly improved. In this case, the depth distances of the plurality of surfaces displaying the plurality of 2D images (107, 108) are focused on the plurality of surfaces when the depth position of the display target object is seen by the observer 100. It is necessary to set it within the range in which the blur of the image is smaller than that of.

Also, unlike the conventional method shown in FIG. 30, a three-dimensional object existing in the middle position of the surface (that is, a three-dimensional object between a plurality of transmissive display devices) is not observed by the observer 100. Since it looks three-dimensional, it has an advantage that it is not a conventional three-dimensional effect like a book split. Furthermore, in the present embodiment, since a three-dimensional object between a plurality of transmissive display devices can be represented, there is an advantage that the amount of data when performing three-dimensional display can be greatly reduced. Further, in the present embodiment, since the physiological or psychological factor of human being or the illusion is utilized only by controlling the transmittance, a coherent light source such as a laser is not particularly required as a light source, and It also has the advantage of being easy to implement. In addition, since the present embodiment does not include a mechanical drive unit, it has an advantage that it is suitable for weight reduction and reliability improvement.

In the above description, a plurality of 2D images (1
07, 108), the case where the transmittance of the portion is changed has been described. For example, a plurality of 2D images (107, 10)
The change in the transmittance of 8) is as described above, and within the range that does not change the overall color viewed from the observer 100, 2
Even if the colors of the D-images (107, 108) are changed, the same effects as the effects of the present invention can be obtained. In this embodiment,
The apparent depth position is changed by the luminance ratio of the front and rear 2D images (107, 108). Therefore, the observer 10
The color (eg, red) of the 2D image 107 on the front transmissive display device 101 is set so that 0 becomes the same as the color (eg, yellow) of the three-dimensional stereoscopic image to be presented when these are overlapped. And a 2D image 10 on the rear transmissive display device 102.
The eight colors (eg, green) can be changed. For example, the color of the contour portion is different from that of the middle color and causes a feeling of discomfort in a normal case. However, in some cases, an effect can be obtained in terms of color matching with the background.

In the present embodiment, among the transmission type display devices for displaying 2D images, only two transmission type display devices are mainly described, and the three-dimensional object presented to the observer 100 is two. Although the case where it is between two transmissive display devices has been described, the same is true even when the number of transmissive display devices that display a 2D image is larger than this or when the position of a three-dimensional object to be presented is different. Obviously, various configurations are possible. Further, the display surface of the two-dimensional image in the present embodiment does not necessarily have to be a flat surface from the point of view of the present invention, and the same applies to a spherical surface, an elliptic surface, a quadric surface, or another complicated curved surface. It is clear that various effects can be obtained.

[Embodiment 2] In the above embodiment, for example, the depth position of the entire three-dimensional object 104 is
Although the method and the device for expressing by using the 2D image displayed on the transmissive display device (101, 102) have been mainly described, the present invention is, for example, as a method and a device for expressing the depth of the three-dimensional object itself. It is clear that can also be used. An important point in this embodiment is that a 2D image (107, 10) is displayed on an apparatus having the same configuration as in FIG.
8) The transmittance of each part is changed according to the depth position of each part of the three-dimensional object 104 while keeping the overall brightness as viewed from the observer 100 constant. An example of how to change it will be described below with reference to FIGS. 7 and 8, taking a case of using two transmissive display devices (for example, 101 and 102 in FIG. 1) as an example. Here, since it is a black-and-white drawing, in FIG. 7 and FIG. 8, the higher brightness is shown darker for easier understanding.

FIG. 7 is an example of a 2D image displayed on a transmissive display device close to the observer (eg 101 in FIG. 1), and FIG. 8 is a transmissive display device far away from the observer (eg FIG. 1).
102) is an example of a 2D image displayed in FIG. For example, when a cake as shown in FIGS. 7 and 8 is taken as an example of the three-dimensional object, the upper surface and the lower surface of the three-dimensional object (for example, cake) are, for example, substantially flat, except for the candle that stands up. It is assumed that the side surface thereof is, for example, a cylindrical shape, and the candle is arranged, for example, near the circumference of the upper surface.
In the 2D image in this case, the upper side is located deeper on the upper and lower surfaces, and the middle is located deeper toward the end on the side, and the hidden upper middle is deeper. Will be located in. In this case, in the transmissive display device (eg, 101 in FIG. 1) close to the observer, as shown in FIG. 7, the change in luminance on the upper surface and the lower surface is a region close to the observer (in a 2D image, for example, The transmittance is gradually changed corresponding to the depth position such that the lower portion has low transmittance and the far portion (for example, upper portion in the 2D image) has higher transmittance.

Further, in the transmissive display device (for example, 102 in FIG. 1) far from the observer, as shown in FIG. 8, the portion near the observer (for example, in the lower part in the 2D image) has the transmittance. It is gradually changed corresponding to the depth position so that the high and far part (for example, the upper part in the 2D image) has low transmittance. Next, in the transmissive display device (for example, 101 in FIG. 1) close to the viewer, the change in the transmittance of the cylindrical portion also corresponds to the depth position, and as shown in FIG. The transmittance is gradually changed so that (for example, the vicinity of the center) has low transmittance, and distant portions (for example, the left and right ends) have high transmittance. Further, in the transmissive display device (eg, 102 in FIG. 1) far from the observer, as shown in FIG.
A part with high transparency near the center and a place far away (for example,
Gradually change so that the transmittance becomes low at the left and right edges. By displaying in this manner, even if a 2D image is displayed due to a physiological or psychological factor of human, or an illusion, an observer (for example, 10 in FIG.
In 0), it seems as if there is a cylindrical cake whose upper and lower surfaces are almost flat.

In this embodiment, a cylindrical object whose upper and lower surfaces are substantially flat is taken as an example, but it is obvious that the same can be applied to objects having other shapes.
In the present embodiment, a case has been described in which the transmittance of the portions of the 2D image displayed on the plurality of surfaces is changed while keeping the overall brightness of the viewer constant. However, it is a technique that is often used in computer graphics to increase the stereoscopic effect by gradually decreasing the overall brightness as seen by the observer, and this is also used in this embodiment. It is clear that adoption can further enhance the effect,
An example thereof will be described below with reference to FIGS. 9 and 10. It is to be noted that, since it is a black-and-white drawing here, in FIG. 9 and FIG. 10, the higher brightness is shown darker for easier understanding.

In FIG. 9, by gradually lowering the brightness of the lower floor portion upward, it is as if the upper floor is deep in the depth direction. Further, in FIG. 10, as in FIG. 9, not only in the floor portion, but also in the chain (object on the ring), the brightness of the left portion is gradually reduced to the left so that the chain in the left portion is deep in the depth direction. You can get an effect that feels like it is. As a method of calculating the degree of such a decrease in brightness, as brightness B ′ for obtaining the above-mentioned effect with respect to the brightness B of the three-dimensional object, for example, B ′ = B × T0 / T (T: distance from the viewpoint) , T
It is obvious that there are many methods such as the calculation formula of 0: distance from the viewpoint to the reference plane).

[Embodiment 3] In each of the above-mentioned embodiments, the case where the 2D image moves three-dimensionally has not been described, but the movement of the observer in the left-right and up-down directions is not limited to the normal two-dimensional movement. This is possible by reproducing a moving image in the transmissive display device as in the case of the three-dimensional display device, and with respect to the movement in the depth direction, it is possible to temporally change the transmissivity of a plurality of transmissive display devices from the contents described above. Then, it is clear that a moving image of a three-dimensional image can be expressed.
An example thereof will be described below with reference to FIG. The main point of the present embodiment is that the transmittance of each part of the 2D image (107, 108) on the device having the same configuration as that of the first embodiment is the overall luminance as seen by the observer 100. Is kept constant, and the depth position of the three-dimensional object is changed corresponding to the temporal change.

As an example thereof, a case where a three-dimensional object moves temporally from the transmissive display device 101 to the transmissive display device 102 will be described. For example, when the three-dimensional object is at the depth position of the transmissive display device 101,
As shown in FIG. 3, the transmittance on the transmissive display device 101 is set so that the luminance of the 2D image 107 is equal to the luminance of the three-dimensional object, and the transmissivity of the 2D image 108 on the transmissive display device 102 is set. The transmissivity of the portion is set to, for example, the maximum value of the transmissive display device. Gradually, for example, the three-dimensional object becomes
In the case where the distance is a little farther than 0 and the transmission type display device 101 side is slightly closer to the transmission type display device 102 side in time, as shown in FIG. , 2D image 1 on transmissive display device 101
The transmittance of the 07 portion is gradually increased with time, and the transmittance of the portion of the 2D image 108 on the transmissive display device 102 is gradually decreased with time.

Further, for example, if the three-dimensional object is the observer 10,
When moving to a position closer to the transmissive display device 102 side than the transmissive display device 101 with time further away from 0, as shown in FIG. 5, it is necessary to move the depth position of the three-dimensional object. Correspondingly, the transmissive display device 101
The transmittance of the portion of the upper 2D image 107 is further increased with time, and the 2D image 108 on the transmissive display device 102 is increased.
The transmittance of the part of is further reduced with time. Finally, for example, when the three-dimensional object has temporally moved to the depth position of the transmissive display device 102, as shown in FIG. 6, the transmissive display is performed corresponding to the movement of the depth position of the three-dimensional object. The transmittance on the device 102 is temporally changed until the brightness of the 2D image 108 becomes equal to the brightness of the three-dimensional object,
In addition, the transmittance of the portion of the 2D image 107 on the transmissive display device 101 is changed, for example, until it reaches the maximum value of the transmissive display device. By displaying in this way, even if the 2D image (107, 108) is displayed due to a physiological or psychological factor of human being, or an illusion, it is as if it is a transmissive display to the observer 100. Device (10
1, 102), the three-dimensional object 104 feels from the transmissive display device 101 to the transmissive display device 102 in the depth direction.

In the present embodiment, the three-dimensional object 104 changes from the transmissive display device 101 to the transmissive display device 1.
The case of moving to 02 is described. However, when moving from a depth position in the middle between the transmissive display devices (101, 102) to the transmissive display device 102, or from the transmissive display device 101 to the transmissive display device ( 101, 102)
When moving to a depth position on the way between the transmissive display devices (101, 102) to another depth position on the way between the transmissive display devices (101, 102). It is clear that the same thing can be done even if it does. In addition, in the present embodiment, only two transmissive display devices (101, 102) among the transmissive display devices for arranging a 2D image (two-dimensional image) will be mainly described, and the observer 100 2 objects to present
The case of moving between two transmissive display devices (101, 102) has been described, but the number of transmissive display devices for arranging a 2D image is larger than this, or three-dimensional objects to be presented are plural transmissive display devices. Even when the display device is moved across, it is obvious that the same configuration is possible and the same effect can be expected.

[Embodiment 4] In each of the above embodiments,
When viewed from an observer (for example, 100 in FIG. 1), a light source (for example, 110 in FIG. 1) is arranged behind the plurality of transmissive display devices (for example, 101 and 102 in FIG. 1), and Although the case of utilizing the change is described, the effect of the present invention can be obtained even when the change of the transmittance and the change of the scattering degree are used by using a device capable of changing the transmittance and the scattering degree in a plurality of transmissive display devices. be able to. 11 to 13,
An example is shown below. First, as shown in FIG.
A plurality of transmissive display devices (401, 4
It is conceivable that the light source (403, 404) is arranged in each of 02). For example, two transmissive display devices (40
1, 402) and a light source (403, 404) are used as an example, the effect of the present invention brought about by the change in the transmittance described in FIG.
03 from the front of the transmissive display device 401, and from the rear transmissive display device 402 the change of the transmissivity of the front transmissive display device 401.

That is, the 2D image 407 displayed on the front transmissive display device 401 is a scattering degree from the light source 403, the intensity of light from the rear transmissive display device 402 and the front transmissive display device 401. Determined by the transparency at
2D image 40 displayed on the rear transmissive display device 402
8 is determined by the light intensity of the light source 404. As a result, the control of the depth position is somewhat complicated as compared with the above-described embodiments, but there are advantages such as the degree of freedom in the device configuration such as the degree of freedom in the arrangement of the light sources. In this case, as shown in FIG. 12, it is conceivable that a light source is further added and a light source 405 is provided behind the transmissive display device 402 at the rear. In this case, the front transmissive display device 401
Since the rear transmissive display device 402 and the rear transmissive display device 402 can be handled almost equally, there is an advantage that the device can be easily controlled. further,
As shown in FIG. 13, illuminating the front and rear transmissive display devices (401, 402) with the respective light sources (403, 404) is also beneficial from the effective use of light from the light sources. In addition,
In this embodiment, as an example, two transmissive display devices (4
01, 402) is used, but it is clear that the same effect can be expected even if the number is increased. Further, from the viewpoint of optics, it is possible to increase the degree of freedom of arrangement and freely change the depth position of an image by combining a plurality of transmissive display devices (401, 402) with lenses and mirrors in the present embodiment. it is obvious.

[Fifth Embodiment] A transmissive display device usable in each of the above-described embodiments will be described below. FIG. 14 is a perspective view showing an example of the transmissive display device in each of the embodiments. The transmissive display device shown in FIG. 14 changes the transmissivity of red in the light from the light source, and the transmissive display device 301 in which almost all the green and blue light is transmitted, and the transmissivity of green is changed. However, it is formed by stacking a green transmissive display device 302 that transmits almost all red and blue light and a blue transmissive display device 303 that changes the transmittance of blue and transmits almost all red and green light. It Such a display device can be realized by, for example, a display device using various liquid crystals described in detail later. Also, as a transmissive display device,
A uniform display device that uniformly changes the transmittance of light from the light source over the entire visible light range is used, and the light source is changed, for example, in red, green, and blue in a time-division manner, and a synchronization device is used. Even if the change in the color of the light source and the display image displayed on the uniform display device are synchronized with each other, as shown in FIG.
It is possible to obtain an effect similar to that shown in.

Next, FIGS. 15 to 23 show a variable polarization device capable of changing the polarization direction in each pixel unit, and a transmission type display device having a structure in which a polarizing plate is arranged on the light emitting side of the variable polarization device. An example is shown. Since the polarization changing device can change the polarization direction, the intensity of the emitted light can be changed depending on the polarization direction of the outgoing light and the polarization direction of the polarizing plate on the outgoing side.
The light transmittance can be changed as a whole. Here, for example, red, green, and blue filters are alternately arranged in each pixel, and the light source is changed in a time-sharing manner, for example, red, green, and blue, so that full-color transmission is achieved. It is clear that the degree can be controlled. Further, for example, it is clear that using a polarizing light source or disposing a polarizing plate on the incident side is also effective for improving controllability.

FIG. 15 is a cross-sectional view of an essential part showing an example of a twisted nematic liquid crystal display which can be used in the transmissive display device of each of the above embodiments. The basic structure of the twisted nematic liquid crystal display is, for example, ITO.
Or a transparent conductive film (503, 50) formed of SnOx or the like.
4) sandwiches the liquid crystal 501, and a polarizing plate (50
7, 508) are arranged. Here, an alignment film (505, 506) for aligning the liquid crystal 501 is arranged on the transparent conductive film (503, 504), and the alignment direction of the alignment film (505, 506) is, for example, up and down. It is orthogonalized. When no voltage is applied to the transparent conductive films (503, 504), the liquid crystal molecules of the liquid crystal 501 are aligned by the alignment regulating force of the alignment films (505, 506).
5, 506) near the transparent conductive film (50
3, 504) parallel to the alignment direction. In this case, as shown in FIG. 16A, the liquid crystal molecules have a twisted structure, and the polarization direction of the incident light changes by 90 degrees, for example, according to this structure. On the other hand, as shown in FIG. 16B, a sufficient voltage V5a is applied to the transparent conductive films (503, 504).
When is applied, the liquid crystal molecules are aligned vertically by the electric field in the electric field direction, for example, the transparent conductive films (503, 504), and the polarization of the transmitted light does not change. When the voltage is V5a or less, the polarization direction continuously changes according to the voltage. As described above, in the twisted nematic liquid crystal display, the polarization direction of the emitted light can be changed by the voltage applied to the transparent conductive film (503, 504).
Since the intensity of the emitted light can be changed by the polarizing plate 507 provided on the light emitting side, it is possible to change the light transmittance as a whole.

FIG. 17 is a cross-sectional view of essential parts showing an example of an in-plane type liquid crystal display usable in the transmissive display device of each of the above-mentioned embodiments. The basic configuration of the in-plane type liquid crystal display is such that the liquid crystal 513 is sandwiched between the alignment films (512, 514) and the liquid crystal 513 is placed outside the alignment film 514, for example
A transparent conductive film (511, formed of TO, SnOx, etc.)
515), and a polarizing plate (507,
508) is arranged. Here, the transparent conductive films (511, 515) are in the same plane, and the alignment directions of the alignment film 512 and the alignment film 514 are parallel. Figure 1
As shown in FIG. 8A, the transparent conductive film (511, 515)
When no voltage is applied between them, the liquid crystal molecules of the liquid crystal 513 are aligned in the alignment direction of the alignment films (512, 514) by the alignment regulating force of the alignment films (512, 514). On the other hand, as shown in FIG. 18B, the transparent conductive film (51
1, 515), a sufficient voltage V5b higher than the threshold voltage is applied, and the liquid crystal molecules are aligned in the applied voltage direction. In this way, the direction in which the liquid crystal molecules having birefringence are aligned changes, so that the polarization state of the emitted light can be changed. Further, when the voltage applied between the transparent conductive films (511, 515) is V5b or less, a change in the polarization direction according to the voltage is continuously obtained. As described above, in the in-plane type liquid crystal display, the transparent conductive film (511, 515) is used.
The polarization direction of the outgoing light can be changed by the voltage applied between the polarizing plates 507 and 507, which are provided on the outgoing side of the light.
Thus, the intensity of the emitted light can be changed, so that the light transmittance as a whole can be changed.

FIG. 19 is a cross-sectional view of essential parts showing an example of a homogeneous type liquid crystal display which can be used in the transmissive display device of each of the embodiments. The basic structure of the homogeneous liquid crystal display is, for example, a transparent conductive film (521, 525) formed of ITO, SnOx, or the like, with a liquid crystal (for example, nematic liquid crystal) 523 sandwiched between the polarizing plates (507, 508). ) Is arranged. Here, the liquid crystal 523 is formed on the transparent conductive film (521, 525).
Alignment films (522, 524) for orienting the are arranged. Note that since the liquid crystal of homogeneous alignment is used in the transmissive display device illustrated in FIG. 19, the alignment direction of the alignment film 522 and the alignment direction of the alignment film 524 are the same (parallel).
Further, in the homogeneous type liquid crystal display, as shown in FIG.
As shown in FIG.
2,524) and the incident direction is shifted. For example,
In the case of linearly polarized light, it is an intermediate direction between the 0-degree direction and the 90-degree direction, and for example, it is incident with a shift of 45 degrees, or is circularly polarized light or elliptically polarized light. As shown in FIG. 21B, when a sufficient voltage V5c equal to or higher than the threshold voltage is applied between the transparent conductive films (521, 525), the liquid crystal molecules of the liquid crystal 523 are aligned in the applied voltage direction. Therefore, the polarization direction of the incident light is emitted with almost no change. On the other hand, as shown in FIG. 21A, the transparent conductive film (521,
If no voltage is applied between 525), the alignment film (52
2, 524), the liquid crystal molecules are oriented in the alignment direction of the alignment film (522, 524) and the alignment film (5
22, 524). Therefore, the incident light is emitted with its polarization direction changed due to the birefringence of the liquid crystal molecules. When the voltage applied between the transparent conductive films (521, 525) is V5c or less, a change in the polarization direction corresponding to the voltage is continuously obtained. As described above, in the homogeneous liquid crystal display, the transparent conductive film (521, 52
5) The polarization direction of the emitted light can be changed by the voltage applied between the polarizing plates 50 provided on the light emitting side.
7, the intensity of the emitted light can be changed, so that the light transmittance as a whole can be changed.

FIG. 22 is a cross-sectional view of an essential part showing an example of a ferroelectric or antiferroelectric liquid crystal display that can be used in the transmissive display device of each of the above embodiments. The basic structure of a ferroelectric or antiferroelectric liquid crystal display is, for example, I
Transparent conductive film (533, formed of TO, SnOx, etc.)
534), a liquid crystal (for example, ferroelectric liquid crystal or antiferroelectric liquid crystal) 531 is sandwiched, and a polarizing plate (50
7, 508) are arranged. Here, an alignment film (535, 536) for aligning the liquid crystal 531 is disposed on the transparent conductive film (533, 534). As shown in FIG. 23, the direction of spontaneous polarization of the liquid crystal 531 changes according to the direction of the electric field applied between the transparent conductive films (533, 534), so that the liquid crystal 531 (ferroelectric liquid crystal or anti-ferroelectric liquid crystal) Make the thickness sufficiently thin (for example, 1 μm to 2
If it is set to about μm), the spontaneous polarization of the liquid crystal 531 changes in the same plane as the transparent conductive film (533, 534).
As described above, in the ferroelectric or antiferroelectric liquid crystal display, the alignment direction of the liquid crystal molecules having birefringence changes depending on the voltage applied between the transparent conductive films (533, 534), so that the polarization of the emitted light is changed. The state can be changed, whereby the intensity of the emitted light can be changed by the polarizing plate 507 provided on the light emitting side, and the light transmittance as a whole can be changed.

[Sixth Embodiment] FIG. 24 is a perspective view showing an example of the transmissive display device of each of the foregoing embodiments. In the transmissive display device using the variable polarization device as described above, when a plurality of the display devices are stacked in series, a large number of polarizing plates are required, so that the transmittance is low as a whole and the display is dark. . Therefore, as shown in FIG. 24, a polarization variable device (for example, the twisted nematic liquid crystal display, the in-plane liquid crystal display device, the homogeneous liquid crystal display device, the ferroelectric liquid crystal display device, the anti-ferroelectric liquid crystal display device described above) is used. (Device without the polarized sheet) (3
It is possible to prevent the display from becoming dark by arranging a plurality of (11 to 31n) and sandwiching the whole between two polarizing plates (321, 322). However, in the present embodiment, the polarization direction is changed by each of the polarization variable devices (311 to 311).
It is necessary to control the polarization direction of each polarization variable device (311 to 31n) in consideration of the change while passing a plurality of n). The polarization variable device (311 to 31n) of the present embodiment also has an advantage that the brightness of each device can be controlled with a substantially large degree of freedom. That is, in the above-described transmissive display device, the light from the light source does not change or decreases while passing through each device,
The brightness in each device remains unchanged or has only a degree of freedom to decrease.

On the other hand, in the present embodiment,
The amount of light hardly changes up to the polarizing plate 321 on the exit side, and only the polarization direction of each polarization variable device (311 to 31n) changes. Moreover, the polarization directions are almost added and rotated by the respective polarization variable devices (311 to 31n), but when observed from the outside of the emission side polarization plate 321, the transmission polarization direction of the emission side polarization plate 321 is changed. As a reference, the brightness of each polarization variable device (311 to 31n) decreases from 0 to 90 degrees, the brightness increases from 90 to 180 degrees, and
The brightness decreases up to 80 to 270 degrees, and increases up to 270 to 360 degrees, so that the brightness can be repeatedly increased and decreased. Therefore, each polarization variable device (311 to 311)
The brightness of 1n) can be increased, unchanged, or decreased as compared with the brightness of the polarization variable device immediately before that. Here, for example, by arranging red, green, and blue filters alternately in each pixel, or by changing the light source, for example, red, green, and blue in a time division manner,
It is clear that full-color brightness control is possible.

FIG. 25 is a perspective view showing an example of the transmissive display device of each of the above embodiments. The transmissive display device shown in FIG. 25 is obtained by applying the present embodiment to the device shown in FIG. The transmissive display device shown in FIG. 25 includes, for example, a red polarization variable device 331 that changes the polarization direction of red in the light from the light source, and transmits the light without changing the polarization directions of green and blue. The green polarization variable device 332 that changes the polarization direction of the light and transmits the red and blue polarization directions with almost no change.
And a blue polarization changing device 333 which changes the polarization direction of blue and transmits the polarization directions of red and green with almost no change. Such a display device can be easily realized, for example, by a configuration in which a polarizing plate is removed from a display device using various liquid crystals.

One of the great merits in this embodiment is that the entire display can be brightened, as described above, and the other is that the addition / subtraction of the luminance can be freely performed. For example, when the brightness of the two-dimensional image displayed on each display surface is changed by changing the transparency described above, basically only the subtraction of the brightness is possible. That is, it is difficult to increase the brightness of the subsequent two-dimensional display device again when the transmittance is lowered and the brightness is reduced in a certain two-dimensional display device. To do this, light must be replenished from outside the two-dimensional display device along the way. For example, it is necessary to newly provide a device that is provided with illumination for each display surface and sequentially controls the illumination degree, or that is capable of controlling illumination for each pixel.

On the other hand, when the polarization direction is changed, the same brightness is given if the angles of the polarization directions of the polarizing plates on the emission side (observer side) measured from the vertical direction are the same. That is, for example, even when angles are sequentially added clockwise in the polarization direction, there are four points having the same brightness, for example, 0 to 360 degrees. Of course, since the polarized light is a target of rotation, it will be the same if it is rotated 360 degrees, and this is also the case when the angles are added counterclockwise. Therefore, even if the rotation angle of the polarization direction is one direction, the brightness can be effectively added or subtracted unlike the case of the transmittance. actually,
For example, in a twisted nematic liquid crystal display device, the maximum angle change is often 90 degrees, and therefore it is necessary to design in consideration of this.

[Embodiment 7] Another transmissive display device usable in each of the above embodiments will be described below. FIG. 26 is a main-portion cross-sectional view showing an example of a guest-host liquid crystal display which can be used for the transmissive display device of each of the embodiments. The basic constitution of the guest-host type liquid crystal display is a mixture containing a liquid crystal 541 and a dichroic dye 542 (a dye that emits different colors depending on the direction of the molecule, especially when one of the dyes becomes nearly colorless). , For example,
A transparent conductive film formed of ITO, SnOx, or the like (54
3, 544), and the transparent conductive film (543,
544), alignment films (545, 546) are arranged to align the liquid crystal 541 in one direction. In a guest-host type liquid crystal display, a transparent conductive film (5
43,544) when no voltage is applied to the liquid crystal 54
1 is aligned in parallel with the transparent conductive film (543, 544) by the alignment regulating force of the alignment film (545, 546). Then, the dichroic dye 542 is also aligned in parallel by being dragged by the liquid crystal 541, and the transmitted light emits a color different from colorless, for example. On the other hand, when a voltage is applied between the transparent conductive films (543, 544), the liquid crystal 541 is aligned by the electric field in the electric field direction, for example, perpendicular to the transparent conductive films (543, 544). Then, the dichroic dye 5 is attracted to the liquid crystal 541.
42 is also arranged vertically, and the transmitted light becomes colorless, for example. As described above, according to the guest-host type liquid crystal display, the light transmittance can be changed. Here, it is apparent that the transmittance of full color can be controlled by arranging the guest-host type liquid crystal display having three colors of yellow, magenta and cyan in series with the dichroic dye 542. It is also apparent that black is used for the dichroic dye 542 and the transmittance of full color can be controlled in a time-division manner.

FIG. 27 is a cross-sectional view of essential parts showing an example of a polymer dispersed liquid crystal display usable in the transmissive display device of each of the above-mentioned embodiments. The basic structure of a polymer dispersed liquid crystal display is that a polymer dispersed liquid crystal layer in which liquid crystals 552 are dispersed in a polymer 551 in a granular form is used as a transparent conductive film (55).
3, 554). For example, when no voltage is applied to the transparent conductive film (553, 554), the liquid crystal 552 is oriented in a random direction, and thus has a refractive index different from that of the polymer 551. Are scattered and their intensity is reduced. On the other hand, when a voltage is applied to the transparent conductive film (553, 554), the liquid crystal 552 faces the electric field direction and has, for example, a refractive index almost the same as that of the polymer 551, so that the incident light is transmitted as it is and its intensity is does not change. As described above, according to the polymer-dispersed liquid crystal display, the light transmittance can be changed. Here, it is clear that the refractive index may be equal to that of the polymer 551 when the liquid crystal 552 is oriented in a random direction, and may be different from that of the polymer 551 when oriented in the direction of the electric field. is there. In addition, for each pixel, for example, red, green, and blue filters are alternately arranged, and the light source is changed in a time-sharing manner, for example, red, green, and blue, so that full-color transmittance control can be performed. It is clear that you can do it. Furthermore, it is apparent that the same effect can be obtained by dispersing the liquid crystal and the dichroic dye in the polymer in a granular form in combination with the guest-host type shown in FIG.

FIG. 28 is a cross-sectional view of an essential part showing an example of a holographic polymer dispersion type liquid crystal display which can be used in the transmission type display device of the above respective embodiments. The basic structure of a holographic polymer-dispersed liquid crystal display is a holographic polymer-dispersed liquid crystal layer in which liquid crystals 562 are dispersed in a polymer 561 in a granular form, and a transparent conductive film (56
3,564). Here, the liquid crystal 562
The particles are smaller than the wavelength used and are arranged in layers as shown in FIG. 28. For example, when no voltage is applied to the transparent conductive films (563, 564), the liquid crystal 562 is oriented randomly, and therefore has a refractive index different from that of the polymer 561. Are scattered and cause Bragg reflection due to the layered arrangement, the direction of which is greatly changed, and the intensity thereof is reduced. On the other hand, when a voltage is applied to the transparent conductive films (563, 564), the liquid crystal 562 is oriented in the direction of the electric field and has, for example, a refractive index almost the same as that of the polymer 561, so that Bragg reflection does not occur and the incident light remains unchanged. It penetrates and its intensity does not change. As described above, according to the holographic polymer-dispersed liquid crystal display, the light transmittance can be changed. Here, it is clear that the refractive index may be equal to that of the polymer 561 when the liquid crystal 562 is oriented in a random direction, and may be different from that of the polymer 561 when oriented in the direction of the electric field. .

Further, for each pixel, for example, red, green, and blue filters are alternately arranged, and a light source is, for example, red,
It is clear that full-color transparency control can be performed by changing the time division between green and blue. Further, it is apparent that the same effect can be obtained by dispersing the liquid crystal and the dichroic dye in the polymer in a granular form in combination with the guest-host type shown in FIG. Although the invention made by the present inventor has been specifically described based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Of course,

[0053]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows. (1) According to the present invention, it becomes possible to display a three-dimensional moving image without using glasses. (2) According to the present invention, it is possible to suppress the contradiction between the physiological factors of stereoscopic vision. (3) According to the present invention, the amount of information can be reduced and an electrically rewritable three-dimensional moving image can be displayed.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of a three-dimensional display device according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the principle of the three-dimensional display device according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining the principle of the three-dimensional display device according to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining the principle of the three-dimensional display device according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining the principle of the three-dimensional display device according to the first embodiment of the present invention.

FIG. 6 is a diagram for explaining the principle of the three-dimensional display device according to the first embodiment of the present invention.

FIG. 7 is a diagram showing an example of a 2D image displayed on a transmissive display device in front of the three-dimensional display device according to the second embodiment of the present invention.

FIG. 8 is a diagram showing an example of a 2D image displayed on the transmissive display device behind the three-dimensional display device according to the second embodiment of the present invention.

FIG. 9 is a diagram showing an example of a three-dimensional stereoscopic image displayed on the three-dimensional display device according to the second embodiment of the present invention.

FIG. 10 is a diagram showing an example of a three-dimensional stereoscopic image displayed on the three-dimensional display device according to the second embodiment of the present invention.

FIG. 11 is a diagram showing a schematic configuration of a three-dimensional display device according to a fourth embodiment of the present invention.

FIG. 12 is a diagram showing a schematic configuration of another example of the three-dimensional display device according to the fourth embodiment of the present invention.

FIG. 13 is a diagram showing a schematic configuration of another example of the three-dimensional display device according to the fourth embodiment of the present invention.

FIG. 14 is a perspective view showing an example of the transmissive display device of each of the embodiments.

FIG. 15 is a cross-sectional view of essential parts showing an example of a twisted nematic liquid crystal display that can be used in the transmissive display device of each of the embodiments.

FIG. 16 is a diagram for explaining the operation of the twisted nematic liquid crystal display.

FIG. 17 is a cross-sectional view of an essential part showing an example of an in-plane type liquid crystal display usable in the transmissive display device of each of the embodiments.

FIG. 18 is a diagram for explaining the operation of the in-plane type liquid crystal display.

FIG. 19 is a main-portion cross-sectional view showing an example of a homogeneous liquid crystal display which can be used for the transmissive display device of each of the embodiments.

FIG. 20 is a diagram for explaining the operation of the homogeneous liquid crystal display.

FIG. 21 is a diagram for explaining the operation of the homogeneous liquid crystal display.

FIG. 22 is a cross-sectional view of essential parts showing an example of a ferroelectric or antiferroelectric liquid crystal display usable in the transmissive display device of each of the above-described embodiments.

FIG. 23 is a diagram for explaining the operation of the ferroelectric or antiferroelectric liquid crystal display.

FIG. 24 is a perspective view showing an example of the transmissive display device of each of the embodiments.

FIG. 25 is a perspective view showing an example of the transmissive display device of each of the embodiments.

FIG. 26 is a main-portion cross-sectional view showing an example of a guest-host liquid crystal display which can be used for the transmissive display device in each of the above embodiments.

FIG. 27 is a main-portion cross-sectional view showing an example of a polymer-dispersed liquid crystal display which can be used for the transmissive display device of each of the embodiments.

FIG. 28 is a main-portion cross-sectional view showing an example of a holographic polymer-dispersed liquid crystal display which can be used in the transmissive display device of each of the embodiments.

FIG. 29 is a diagram showing a schematic configuration of an example of a conventional three-dimensional display device.

FIG. 30 is a diagram showing a schematic configuration of another example of a conventional three-dimensional display device.

[Explanation of symbols]

100, 400, 607 ... Observer, 101, 102, 4
01, 402 ... Transmissive display device, 103 ... Optical system, 10
4, 601, 611 ... Three-dimensional object, 105, 106, 1
07,108,407,408 ... 2D image, 110,4
03, 404, 405 ... Light source, 301 ... Red transmissive display device, 302 ... Green transmissive display device, 303 ... Blue transmissive display device, 311 to 31n ... Polarization variable device, 321, 32
2, 507, 508 ... Polarizing plate, 331 ... Red polarization changing device, 332 ... Green polarization changing device, 333 ... Blue polarization changing device, 501, 513, 523, 531, 541, 55
2,562 ... liquid crystal, 503, 504, 511, 515
521, 525, 533, 534, 543, 544, 5
53, 554, 563, 564 ... Transparent conductive film, 505
506, 512, 514, 522, 524, 535, 5
36, 545, 546 ... Alignment film, 542 ... Dichroic dye,
551, 561 ... Polymer, 602, 603 ... Camera, 6
04 ... video signal conversion device, 605 ... CRT display device, 6
06 ... Liquid crystal shutter glasses, 612 ... Collection of depth sampled images, 613 ... Volume display device, 614 ... Three-dimensional redevelopment.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Munekazu Date 3-3-1 Otemachi, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (56) References JP 2000-214413 (JP, A) (58) ) Fields surveyed (Int.Cl. ⁷ , DB name) H04N 13/00

Claims (33)

(57) [Claims] 1. A two-dimensional image generated by projecting a display target object from a line-of-sight direction of the observer on a plurality of display surfaces at different depth positions as viewed from the observer, and the generated two-dimensional image An image is displayed on each of a plurality of display surfaces at different depth positions viewed from the observer, and the brightness of the displayed two-dimensional image is changed independently for each of the display surfaces to obtain a three-dimensional stereoscopic image. A three-dimensional display method for generating, wherein the transmittance of a two-dimensional image displayed on each display surface is independently changed for each display surface, and the two-dimensional display on each display surface is performed. A three-dimensional display method characterized by independently changing the brightness of an image. 2. A two-dimensional image generated by projecting a display target object from a line-of-sight direction of the observer on a plurality of display surfaces at different depth positions as viewed from the observer, and the generated two-dimensional image An image is displayed on each of a plurality of display surfaces at different depth positions viewed from the observer, and the brightness of the displayed two-dimensional image is changed independently for each of the display surfaces to obtain a three-dimensional stereoscopic image. A three-dimensional display method for generating, wherein the polarization direction of a two-dimensional image displayed on each of the display surfaces is independently changed for each of the display surfaces, and the two-dimensional image is displayed on each of the display surfaces. A three-dimensional display method characterized by independently changing the brightness of an image. 3. The two-dimensional image displayed on a display surface of the plurality of display surfaces close to the observer when the display target object is an object displayed at a depth position close to the observer. The transmittance of the two-dimensional image displayed on the display surface far from the observer is high, and the display target object is an object displayed at a depth position far from the observer. In this case, the transmittance of the two-dimensional image displayed on the display surface closer to the observer among the plurality of display surfaces is increased, and the transmittance of the two-dimensional image displayed on the display face far from the observer is increased. 3. The three-dimensional display method according to claim 1, wherein the three-dimensional display method is set to be low. 4. The two-dimensional images are displayed on the plurality of display surfaces so that the two-dimensional images overlap each other when viewed from a point on a line connecting the right eye and the left eye of the observer, and the observer also The three-dimensional display method according to any one of claims 1 to 3, characterized in that the overall brightness viewed by is equal to the brightness of the original display target object. 5. The two-dimensional images are displayed on the plurality of display surfaces so that the two-dimensional images overlap with each other when viewed from a point on a line connecting the right eye and the left eye of the observer, and a display target object is displayed. The three-dimensional display according to any one of claims 1 to 3, wherein the depth position of the two-dimensional image is higher when the depth position is far from the observer than when the depth position is near. Method. 6. The tertiary according to claim 4 or 5, wherein one point on a line connecting the right eye and the left eye of the observer is set between the right eye and the left eye. Original display method. 7. The three-dimensional display according to claim 4, wherein a point on a line connecting the right eye and the left eye of the observer is set as a center point of the right eye and the left eye. Method. 8. A left-right direction viewed from the observer with respect to a two-dimensional image displayed on each display surface so that the two-dimensional images are overlapped when viewed from a point on a line connecting the right eye and the left eye of the observer. The three-dimensional display method according to any one of claims 4 to 7, characterized in that a modification of enlargement / reduction is added to. 9. The depth position between the display surfaces for displaying the two-dimensional image is determined such that a plurality of two-dimensional images displayed on the same display target object on the display surfaces are the right eye and the left eye of the observer. The three-dimensional display method according to any one of claims 1 to 8, wherein the range is a range having a common region when viewed from the eye position with a single eye. 10. The depth position between the display surfaces displaying the two-dimensional images is displayed on the same display target object when a plurality of two-dimensional images displayed on those display surfaces are viewed by the observer. 10. The image focusing apparatus according to claim 1, wherein focusing on a depth position of an object is within a range in which an image is less blurred than focusing on the plurality of display surfaces. 3D display method. 11. The three-dimensional moving image is displayed by sequentially switching the two-dimensional image according to a temporal change, and the three-dimensional moving image is displayed.
The three-dimensional display method described in the item. 12. The switching of the two-dimensional images when the two-dimensional image includes a plurality of object images moving in the depth direction and the moving direction of the objects is a direction approaching the observer. In synchronism, the transmittance of the object image displayed on the display surface closer to the viewer among the plurality of display surfaces is sequentially decreased, and the transmittance of the object image displayed on the display surface far from the viewer is reduced. sequentially high and, when the moving direction of the object is a direction away from the observer in synchronism with the switching of the two-dimensional image,
Of the plurality of display surfaces, the transmittance of the object image displayed on the display surface closer to the viewer is sequentially increased, and the transmittance of the object image displayed on the display surface distant from the viewer is sequentially decreased. The three-dimensional display method according to claim 11, further comprising: 13. A first means for generating a two-dimensional image in which a display target object is projected from a line-of-sight direction of the observer on a plurality of display surfaces at different depth positions when viewed from the observer, A plurality of transmissive display devices which are arranged at different depth positions as viewed from the observer and which respectively display the two-dimensional images generated by the first means; and the transmissive display devices which are displayed on the transmissive display devices. A three-dimensional display device comprising: second means for independently changing the transmittance of the two-dimensional image generated by the first means for each transmission type display device. 14. Each of the transmissive display devices displays the two-dimensional image generated by the first means so as to overlap with each other when viewed from a point on a line connecting the right eye and the left eye of the observer. The three-dimensional display device according to claim 13, wherein: 15. The transmissive display device displays the two-dimensional image generated by the first means by enlarging or reducing the image in the left-right direction when viewed from the observer. The three-dimensional display device according to claim 14. 16. A first light source is disposed behind the plurality of transmissive display devices as viewed from the observer, wherein each transmissive display device transmits light from the first light source. The three-dimensional display device according to any one of claims 13 to 15, wherein the degree is changed. 17. At least one second light source arranged in front of the plurality of transmissive display devices, wherein each transmissive display device includes light from the at least one second light source. 13. The scattering degree or the rate of change of light is changed, and the transmittance of light from a transmission type display device located behind is changed.
The three-dimensional display device according to any one of 6 above. 18. A small number of the plurality of transmissive display devices .
At least one is a device that changes the transmittance of red in the light from the light source and transmits almost all of the green and blue light, and a device that changes the transmittance of green and changes the transmittance of red and blue to almost the same. 17. The three-dimensional structure according to claim 13, further comprising: a device that transmits all light and a device that changes the transmittance of blue light and transmits almost all red and green light. Display device. 19. A small number of the plurality of transmissive display devices .
At least one is a uniform display device that uniformly changes the transmittance of light from the light source over almost the entire visible light range, and a light source that changes the emission color at high speed, such as red, green, and blue in a time division manner. The three-dimensional display device according to any one of claims 13 to 16, further comprising: a synchronization device that synchronizes a color change of the light source with a display of the uniform display device. 20. The plurality of transmissive display devices include a plurality of polarization changing devices capable of changing a polarization direction of light, and further have polarizing plates sandwiching all or a part of the plurality of polarization changing devices. The three-dimensional display device according to any one of claims 13 to 15. 21. A light source that changes its emission color at high speed, such as red, green, and blue in a time-division manner, and a synchronization device that synchronizes the color change of the light source with the display of the plurality of transmissive display devices. The three-dimensional display device according to claim 20, further comprising: 22. The plurality of transmissive display devices change the polarization direction of red in the light from the light source, and change the polarization directions of green and blue little, and change the polarization direction of green. , A device that hardly changes the polarization directions of red and blue, and a device that changes the polarization directions of blue and hardly change the polarization directions of red and green. Furthermore, a polarizing plate that sandwiches these devices in whole or in part. The three-dimensional display device according to any one of claims 13 to 15, further comprising: 23. Each of the transmissive display devices comprises a polarization variable device, and an emission-side polarization plate provided on the emission side from the polarization variable device. The three-dimensional display device according to item 1. 24. The three-dimensional display device according to claim 23, further comprising an incident side polarization plate provided on the incident side from the polarization changing device. 25. The liquid crystal display according to claim 13, wherein at least one of the plurality of transmissive display devices is a twisted nematic liquid crystal display.
The three-dimensional display device according to any one of 1. 26. The three-dimensional structure according to claim 13, wherein at least one of the plurality of transmissive display devices is an in-plane type liquid crystal display. Display device. 27. The three-dimensional display device according to claim 13, wherein at least one of the plurality of transmissive display devices is a homogeneous liquid crystal display. . 28. The three-dimensional display device according to claim 13, wherein at least one of the plurality of transmissive display devices is a ferroelectric liquid crystal display. . 29. The three-dimensional structure according to claim 13, wherein at least one of the plurality of transmissive display devices is a guest-host type liquid crystal display. Display device. 30. The three-dimensional structure according to claim 13, wherein at least one of the plurality of transmissive display devices is a polymer dispersed liquid crystal display. Display device. 31. The holographic polymer dispersed liquid crystal display according to claim 13, wherein at least one of the plurality of transmissive display devices is a holographic polymer dispersed liquid crystal display. Three-dimensional display device. 32. Each of the transmissive display devices sequentially switches and displays the two-dimensional image generated by the first means according to a temporal change, and displays a three-dimensional moving image. The three-dimensional display device according to any one of claims 13 to 31. 33. In each of the transmissive display devices, the two-dimensional image generated by the first means includes a plurality of object images moving in a depth direction, and the moving direction of the object is the When the direction of approaching the observer, in synchronization with the switching of the two-dimensional image, the transmittance of the object image to be displayed on the display surface of the plurality of display surfaces close to the viewer is sequentially lowered, The transmittance of the object image displayed on the display surface far from the observer is sequentially increased, and when the moving direction of the object is a direction away from the observer, in synchronization with the switching of the two-dimensional image. ,
Among the plurality of display surfaces, sequentially increasing the transmittance of the object image displayed on the display surface closer to the observer, and sequentially decreasing the transmittance of the object image displayed on the display surface far from the observer. 33. The three-dimensional display device according to claim 32, wherein: