JPH10232366A - Three-dimensional image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To view a three-dimensional image without specially wearing spectacles with a single image display device and to enable a switching display and a simultaneous display of a two-dimensional image display and the three- dimensional image display by using a liquid crystal element for a parallax barrier arranged between a stereoscopic image display element and a light source lighting the display element from a rear surface. SOLUTION: A liquid crystal display element is used as a three-dimensional(3 D) image displaying display element 3, and a display light selecting optical shutter 2 is arranged on the rear surface of the 3D image displaying display element 3, and a 3D image display element light source 1 is arranged on the rear surface of the display light selecting optical shutter 2. As the display light selecting optical shutter 2, the display element of a device made as thin as possible and having a function transmitting light source light for the 3D image displaying display element 3 through and high definition is preferred, and various liquid crystal display elements are usable. Particularly, as the precise liquid crystal display element with simple element constitution, a ferroelectric liquid crystal display element is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display device capable of displaying a three-dimensional image by a parallax stereogram method, and more particularly, to the display of both a two-dimensional image and a three-dimensional image without any special operation. Is not only possible,
Further, the present invention relates to a three-dimensional image display device capable of simultaneously displaying both a two-dimensional image and a three-dimensional image.

[0002]

2. Description of the Related Art Conventionally, as a method of displaying a three-dimensional image, an observer had to wear glasses having an information selection function for selecting image information in order to separately input left and right image information to left and right eyes. On the other hand, as a technique without glasses, a method of arranging a slit, a lenticular lens, or the like for giving directivity to left and right image information on a three-dimensional image display element has been used and has been improved. Furthermore, recently, the spread of computers and the maintenance of networks have progressed, and various information can be freely viewed through a computer monitor in a wide range from personal use to business use. Various information includes three-dimensional image information, and the importance and use frequency of the three-dimensional image information are increasing.

In the conventional three-dimensional image display device, it is troublesome that the user must wear glasses to view the three-dimensional image display. However, there is a problem that the visual recognition range of the three-dimensional image is narrow. A method of displaying multi-view image information on a three-dimensional image display element in order to widen a three-dimensional image viewing area by a method using the slit or the lenticular lens is adopted. In this case, the same three-dimensional image is used. Also, there is a problem that the resolution is lowered due to an increase in the amount of display information.

Japanese Patent Application Laid-Open No. Hei 5-100009 discloses a method of expanding the viewing range of a three-dimensional image of an observer. It is disclosed to control the position of the arranged parallax barrier. However, in this method, two-dimensional image display and three-dimensional image display are arbitrarily switched, or a three-dimensional image is displayed at an arbitrary part on the same screen, and another part displays a two-dimensional image. A three-dimensional image and a three-dimensional image cannot be displayed simultaneously.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and is intended to view a three-dimensional image without special work such as wearing glasses with a single image display device. It is an object of the present invention to provide an image display device capable of switching between two-dimensional image display and three-dimensional image display and capable of simultaneously displaying two-dimensional images and three-dimensional images on a single screen. . It is another object of the present invention to realize a wide viewing area without deteriorating the display quality of two-dimensional and three-dimensional images following the movement of an observer.

[0006]

According to the present invention, there is provided a stereoscopic image display apparatus using a parallax stereogram method of a stereoscopic image display method, comprising: a stereoscopic image display element and the display element. A liquid crystal element is used for a parallax barrier disposed between the light source and a light source illuminated from the back.

[0007] In one embodiment of the present invention, the parallax barrier is a checkered barrier or a slit barrier. This stereoscopic image display device is used for an information transmission device. Then, the information transmission device has a distance measurement or position measurement function to the observer, and the area of the opening and the light-shielding portion of the liquid crystal element as a parallax barrier,
It can be arbitrarily changed in conjunction with the movement amount of the observer. further,
The two-dimensional image display and the three-dimensional image display can be simultaneously performed by arbitrarily changing the areas of the opening and the light shielding part of the liquid crystal element as a parallax barrier. As the liquid crystal element as the parallax barrier, a light-transmitting ferroelectric liquid crystal element similar to that used for monochrome image display is used. The ferroelectric liquid crystal of the ferroelectric liquid crystal element, when its pretilt angle is α,

[0008]

(Equation 1) 2 ° cone angle and apparent tilt angle θ satisfying the following relationship:
a, and an orientation state where the inclination angle δ of the smectic layer. Further, the width of a pixel for forming the light-transmitting portion and the light-shielding portion of the liquid crystal element is set to about 1/6 of a picture element in the image display element. The width of the pixel of the liquid crystal element as a parallax barrier determines the S / N ratio of each of the left and right eye images when the parallax barrier is moved following the movement of the observer, that is, the fluctuation of the resolution of the stereoscopic image. It is better to make it smaller than 1/3 in order not to make it feel.

[0009]

FIG. 1 is a schematic diagram showing a stereoscopic image display apparatus according to an embodiment of the present invention. In the following,
Unless otherwise specified, a two-dimensional image is described as 2D and a three-dimensional image is described as 3D.

The apparatus shown in FIG. 1 includes a light source (backlight) 1 for a 3D image display element, an optical shutter 2 for selecting display light, and a 3D display.
Image display device 3 and two distance measuring devices 4
The system comprises an observer position measuring device 4 having only a and 4b (only distance measuring devices 4a and 4b are shown in FIG. 1) and a control system of each of the devices 1 to 4. In particular, the output of the observer position measuring device 4 is fed back to the control system of the display light selecting optical shutter 2 and is used as a display control parameter of the display light selecting optical shutter 2. In FIG. 1, illustration of these control systems is omitted. In the device of FIG.
A liquid crystal display element is used as the display element 3 for displaying a 3D image,
A display light selecting optical shutter 2 is provided on the back of the 3D image display display element 3, and a display light selecting optical shutter 2 is provided on the back of the display light selecting optical shutter 2.
A light source 1 for a D image display element is arranged.

Next, the display light selecting optical shutter 2 in FIG. 1 which plays an important role in the present invention will be described. The display light selection optical shutter 2 is a device as thin as possible and has a function of transmitting light source light for the 3D display image display element 3 and a high-definition display element is desirable, and various liquid crystal display elements can be used. is there. Particularly, in the present embodiment, a ferroelectric liquid crystal display element is used as a high definition liquid crystal display element having a simple element configuration.

First, the ferroelectric liquid crystal used in the ferroelectric liquid crystal display device will be additionally described. There are various types of liquid crystal display devices, and various types of driving methods. Among the driving methods, a simple matrix method in which the element configuration is simple and the screen is easily enlarged is widely used. Among the liquid crystals that can use the simple matrix method, there is a ferroelectric liquid crystal. A display device of a type that controls transmitted light by combining with a polarizing element by utilizing the refractive index anisotropy of the ferroelectric liquid crystal molecules is known as clark and Lagerwal.
1) (JP-A-56-107216).
No. 4,367,942). The ferroelectric liquid crystal generally has a non-helical chiral smectic C phase (SmC *) or a chiral smectic H phase (SmH *) in a specific temperature range. It has a property of taking one of the first optical stable state and the second optical stable state and maintaining the state when no electric field is applied, that is, has bistable properties, and has a response to a change in the electric field. And is expected to be widely used as a high-speed and storage type display element.

The fact that the ferroelectric liquid crystal has a memory property is as follows.
When the image display device according to the present embodiment is completely used only for 2D image display, if the ferroelectric liquid crystal display element used as the display light selecting optical shutter 2 is set in a transmissive state to a memory state, a 3D image is displayed. This is preferable in that 2D display can be realized without reducing the resolution of the image display element 3 alone.

Here, the conditions under which the ferroelectric liquid crystal can have memory properties will be described. The orientation state of the ferroelectric liquid crystal is roughly classified into two types, C1 and C2, which will be explained by the difference in the structure of the chevron layer of the smectic phase shown in FIG. Reference numeral 31 in FIG. 2 denotes a smectic phase chevron layer, reference numeral 32 denotes a C1 orientation region, and reference numeral 33 denotes C
Two orientation regions are shown. The smectic liquid crystal generally has a layered structure, but the transition from the SmA phase to the SmC phase or the SmC * phase shortens the layer interval. Therefore, the layer is bent near the center of the upper and lower substrates (30a, 30b) as shown in FIG. Take a structure (chevron structure). here,
The bending direction (orientation state) is C1 as shown in FIG.
And C2, but as is well known, the liquid crystal molecules at the substrate interface form an angle (pretilt) with respect to the substrate due to the uniaxial orientation, and the liquid crystal molecules lean toward the rubbing direction. (It looks like the tip is floating). Because of this pretilt, C1 orientation and C1
The two orientations are not equivalent in elastic energy, and transition may occur at a certain temperature. In addition, transition may occur due to mechanical strain. When the layer structure of FIG. 2 is viewed in a plan view, the boundary 34 at the time of shifting from the C1 orientation to C2 in the rubbing direction A is called a lightning defect in a zigzag lightning shape, and is the boundary at the time of shifting from the C2 orientation to the C1 orientation. 35 is a wide gentle curve and is called a hairpin defect.

Here, there is provided a pair of substrates which have been subjected to a uniaxial alignment process for aligning the ferroelectric liquid crystal, and the pair of substrates is arranged so that the uniaxial alignment directions are substantially parallel to each other and are in the same direction. In the liquid crystal display elements arranged opposite to each other as described above, the pretilt angle of the ferroelectric liquid crystal is α, the tilt angle (１ ／ of the cone angle) is Θ, the layer tilt angle of the SnC * phase is δ, and the ferroelectric liquid crystal is Has an orientation state represented by the following equation, and there are four states having a chevron structure in the C1 orientation state.

[0016]

(Equation 2) The four C1 orientation states are different from the conventional C1 orientation state, and two of the four C1 orientation states form a bistable state (uniform state). Here, assuming that the apparent tilt angle at the time of no electric field is θa, a state showing the relationship of the following equation among the four states of the C1 alignment state is called a uniform state.

[0017]

(Equation 3)

In the uniform state, it is considered from the optical properties that liquid crystal molecules (directors) are not twisted between the upper and lower substrates. FIG. 3A is a schematic diagram showing a director arrangement in each state of the C1 orientation. In the figure 51
54 show the state in which the director in each state is projected on the bottom surface of the cone and this is viewed from the bottom surface direction.
Called director. In FIG. 3A, reference numeral 51 is used.
And 52 are arrangements of C directors which are considered to be in a spray state, and 53 and 54 are arrangements in a uniform state.
As can be seen from the figure, the two states 53 and 54 of the uniform
In, the position of the liquid crystal molecules at the upper or lower substrate interface is replaced with the position in the splay state. FIG. 3 (B)
Indicates a C2 orientation, and there are two states 55 and 56 in internal switching without switching at the interface. This C1
The uniform state of the orientation produces a larger apparent tilt angle θa than the conventionally used bistable state in the C2 orientation, resulting in high luminance and high contrast.

The driving characteristics of a ferroelectric liquid crystal display device using a uniform state exhibiting the above-mentioned bistable state include:
The transition from the first stable state to the other stable state is achieved by applying a certain or more electric field. Further, to return to the original stable state, the polarity of the applied electric field may be reversed.

As described above, the ferroelectric liquid crystal display element has an advantage as an optical shutter for selecting display light, for example, it has a simple structure, can easily achieve high definition, and has a memory property.

FIG. 4 is an operation principle diagram of a stereoscopic image display according to the present invention. In FIG. 4A, the left-eye image information (L) and the right-eye image information (R) are displayed on the display element 3 for 3D image display. An optical shutter 2 for selecting display light is disposed between the 3D image display element light source 1 and the 3D image display element 3, and is divided into an open area and a light-shielded area. . An opening (light transmission) of the display light selection optical shutter 2 is provided to the left eye (L) of the observer 5.
Only the left-eye image information (L) on the 3D image display element 3 illuminated by the unit 2a can be observed. The light source light of the right-eye image information (R) of the display element 3 for 3D image display is cut off by the light shielding portion 2b of the display light selecting optical shutter 2. Therefore, only the left-eye image information is input to the left eye of the observer. Similarly, the right eye (R) of the observer can observe only the right-eye image information (R) of the 3D image display element 3 illuminated by the opening 2a of the display light selecting optical shutter 2. Image information (L) for the left eye of the display element for 3D image display
The light source light is cut off by the light shielding portion 2b of the display light selecting optical shutter 2. Therefore, only the right-eye image information is input to the right eye of the observer. Thereby, the observer 5 can visually recognize the image displayed on the 3D image display device 3 as a 3D image.

When the observer 5 moves as shown in FIG. 4B, the left and right eyes of the observer 5 are both left-eye (L) and right-eye image information (R) on the 3D image display device 3. Will be seen, and the 3D image will not be visible. Therefore, in the present embodiment,
The movement of the observer's viewpoint is measured by a distance measuring system used in a camera or a video camera, the distance to the observer and the amount of movement are calculated, and a ferroelectric liquid crystal display used for the display light selecting optical shutter 2 is used. Feedback is given as display information of the element. For example, in the display of the display light selection optical shutter 2, each opening and light-shielding portion are composed of six pixels (horizontal direction) in FIGS. 4A and 4B. When the viewpoint is shifted as shown in FIG. 4B, an area in which both the right eye and the left eye have an opening and a light-shielding part are seen as B ^* . That is, the right-eye image information (R) and the left-eye image information (L) on the 3D image information display element 3 are in a state where a part of the image information is missing, and cannot be displayed as a 3D image. . Therefore, the pixels in the a ^* region of the display light selecting optical shutter 2 that have been shielded from light before the movement of the viewpoint are opened. The pixels in the b ^* region of the open display light selecting optical shutter are shielded, that is, the pixels are changed from the ON state (transmitted state) to the OFF state (shielded state). Accordingly, a new opening 2a ^* and a light-shielding portion 2b ^* are provided so that the left and right image information can be visually recognized separately by the left and right eyes from the viewpoint after the observer has moved, and can be visually recognized as a 3D image.

In this embodiment, when it is desired to display only a part of the image display device in 3D, an opening and a light-shielding portion may be formed and displayed only in a corresponding area. If all other areas are turned on, 2D display is performed there, and mixed display of 2D display and 3D display on a single screen becomes possible. If all the pixels are turned on, 2D display can be performed on the entire screen. In this case, the display element 3 for displaying a 3D image only has to output image information that is no different from a conventional display.

As described above, according to the present embodiment, in an image display device used for an information transmission device or the like, 3D display can be performed without using glasses or the like, and mixed display of 2D and 3D can be performed. 2D single display was made possible without deteriorating the overall image quality. In addition, by changing the opening and the light-shielding portion on the entire surface of the display element for the display light selection optical shutter in synchronization with the movement of the viewpoint in accordance with the movement of the viewpoint of the observer.
It was confirmed that the viewing area of D display was enlarged.

Further, a transmission type flat display can be used as an optical shutter for selecting display light, but by using a ferroelectric liquid crystal display element having a memory property in the transmission type flat display, 2D display of the entire surface can be performed. It is not necessary to rewrite the display state of the 2D display part in the case where the 2D display and the 3D are mixed, so that the power consumption of the whole system can be suppressed low, and the ferroelectric liquid crystal display element has a simple matrix drive configuration. Therefore, a high-definition 3D image selecting shutter can be realized.

[0026]

EXAMPLE 1 FIG. 5 shows the structure of a display element of a ferroelectric liquid crystal transmission type flat display used as an optical shutter 2 for selecting display light in the above embodiment. Hereinafter, a method for manufacturing the display element in FIG. 5 will be described. The display device shown in FIG. 5 includes two glass substrates 11a and 11b each having a thickness of 1.1 mm. Stripe-shaped ITO transparent electrodes 12a and 12b each having a thickness of about 1500 ° are formed on these substrates 11a and 11b. It is formed by a sputtering method. Insulating layers 10a and 10b are arranged between the transparent electrodes 12a and 12b and the orientation control films 13a and 13b. The insulating layer is PZT-6 (manufactured by Catalyst Kasei Co., Ltd.)
Is printed on a substrate on which ITO is formed by a printing method using a color developing plate, and is preliminarily dried at 80 ° C. for 3 minutes.
The main baking was performed at 0 ° C. to form. To form an alignment control film thereon, a polyamic acid LQ manufactured by Hitachi Chemical Co., Ltd. was used.
It was formed by applying a 1% NMP solution of 1802 with a spinner and firing at 270 ° C. for 60 minutes.

When the upper and lower substrates (11a and 11b) are combined under the same conditions until the orientation control film is formed by the above-described method, the orientation control films 13a and 13b are combined.
The orientation control film of each substrate was subjected to a uniaxial orientation treatment by a rubbing method so that the orientation directions by 13b became substantially parallel. A rubbing cloth made of nylon 66 and having a bristle length of 4 mm was wound around a stainless steel roller having a diameter of 15 cm, and the above uniaxial orientation treatment was performed at 1000 rpm. After a spacer for holding a gap and an adhesive resin are sprayed on one of the pair of substrates 11a and 11b that have been subjected to the orientation processing as described above, the substrates 11a and 11b are overlapped with each other, and the substrates are pressure-bonded. After sealing the periphery of the substrate with a sealant, liquid crystal was injected from an injection port indicated by reference numeral 18 in FIG. 5, and the injection port was sealed to prepare a liquid crystal display element.

The display image size of the display element is 42 μm.
× 42 μm, 8 μm between pixels. This was used as the display light selecting optical shutter 2 in FIG.

As the liquid crystal injected into the device fabricated in this embodiment, a ferroelectric liquid crystal (pyrimidine-based mixed liquid crystal A) was used.
The phase transition temperature and physical properties of the ferroelectric liquid crystal used in this example are shown below.

[0030]

[Table 1] Using the pyrimidine-based mixed liquid crystal A, an element having an alignment control film having a pretilt angle on a display pixel of, for example, 17 ° was formed.

As the display element 3 for displaying a 3D image, any type of transmissive liquid crystal display can be used, but in this embodiment, it has the same structure as the above-described ferroelectric liquid crystal display, and is manufactured by the same method. One used. However, the display pixel size is 92 μm × 292 μm, and the distance between pixels is 8 μm.
μm, and one pixel was formed with a pixel configuration of red, blue, and green, and the size of one pixel was 300 μm × 300 μm. The color filter is composed of the glass substrates 11a and 11b and the transparent electrode 1.
It was formed beforehand between 2a and 12b.

The display element 3 for displaying a 3D image, the optical shutter 2 for selecting the display light, and the light source (backlight) 1 for the 3D image display element arranged on the back of the optical shutter 2 for selecting the display light, produced as described above. 2 distance measuring systems used for cameras for measuring the distance to the observer 3
a, 3b and a 3D image information output device (not shown), 3D
A system having the configuration shown in FIG. 1 was assembled using a ferroelectric liquid crystal display device for an image selection shutter, a display control device, and a distance measurement system control system.

FIG. 6 shows the display state. Now, FIG.
As shown in (A), the left-eye image information (L) and the right-eye image information (R) are converted using two picture elements of the 3D image display device 3 so that 3D image recognition can be performed from a certain observer position. it's shown. Actually, the left image and the right image are arranged and displayed in a stripe shape. One display picture element (30
0 μm × 300 μm) corresponds to 36 pixels (50 × 6 μm × 50 × 6 μm) of the display light selecting optical shutter 2. That is, in order to make the right-eye image information (R) reach the right eye, reference numerals 1 to 1 of the display light selecting optical shutter 2 are used.
6,11-16,21-26,31-36,41-4
36 pixels indicated by reference numerals 6, 51 to 56 are opened (pixels are turned on), and a total of 144 pixels are provided for the upper, lower, left and right pixels.
The pixels are in a light-shielded state (the pixels are in an OFF state). At this time, the ferroelectric liquid crystal display element as the display light selection optical shutter 2 performs a checkerboard display. FIG. 6B schematically shows the whole image. From this state, it is assumed that the viewpoint (position) of the observer has moved in the upper left direction toward the paper surface. In the apparatus of this embodiment, the movement amount of the observer is calculated from the output difference between the two distance measurement systems 3a and 3b (see FIG. 1), and a part of the opening is shielded in accordance with the movement amount, and Redisplay is performed by opening a part. That is, for example, in response to the amount of movement to the upper left, for example, the display state of the * area is inverted and turned on,
5,6,15,16,25,26,3 opened earlier
5,36,41,42,43,44,51,52,5
Redisplay is performed with the 3,54 pixels in the OFF state. Similarly, the same re-display is performed on the other areas that were initially opened. Thereby, the observer can visually recognize the same 3D image information as before the movement even after the movement, and even if the observer moves, the 3D image is not inverted and the image is not blurred.
It was confirmed that good 3D image display recognition was possible.

As a comparative evaluation, 3D image information is displayed on the display light selecting optical shutter 2 in a fixed checkerboard display, and the observer can view the 3D image information.
When the image was moved right and left and up and down from the observation position that can be recognized as D information, the 3D image information was disturbed by even a slight movement, and the image was blurred. This tendency was noticeable as the resolution of the display element 3 for displaying a 3D image was increased. Conversely, as the resolution is lowered, the checkerboard display width of the display light selecting optical shutter 2 becomes coarser, and the sense of obstruction increases. In order to avoid these adverse effects, a system that uses a high-resolution display element and follows the movement of the viewpoint with high sensitivity is necessary. According to the present invention, a high-definition liquid crystal element is used as an optical shutter for selecting display light, and the amount of movement of the viewpoint is increased. It has been confirmed that the system capable of changing the opening and the light-shielding portion is a good 3D image display device.

In FIG. 6B, the entire surface of the liquid crystal element 2 is displayed in a checkered pattern including a light-shielding portion and an opening, and is adapted for displaying a 3D image. If a checkered display including a light-shielding portion and a checkered portion is used, the checkered display portion can be used as a window for displaying 3D image information. At this time, if the pixels in the area other than the checkered display section of the liquid crystal element 2 are opened, the area can be used as a normal 2D image display monitor without any change. Further, a display light selecting optical shutter (liquid crystal element 2
), The entire surface of the display element 1 becomes 2
It can be used as a monitor for D images.

In the above-described embodiment, the checkerboard display is performed on the liquid crystal element as the display light selection optical shutter 2. However, when the display is to respond only to the left and right movements of the observer, the vertical direction is used. A display in the form of a stripe may be performed.

[0037]

As described above, according to the present invention,
2D / 3D display switching display by using a liquid crystal display element as a display light selection optical shutter, and 2D / 3
D image mixed display is possible. Further, since a display light selecting optical shutter suitable for following the viewpoint movement of the observer can be realized, it is possible to provide a stereoscopic image display device in which the observer's 3D display viewing area is enlarged as compared with the conventional one for 3D display. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a 3D / 2D image display system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an orientation model of a smectic layer.

3A is a schematic diagram showing the arrangement of directors at each position between substrates in each state of C1 orientation, and FIG.
It is a schematic diagram which shows two orientations.

FIG. 4 is a diagram illustrating the operation principle of 3D display according to the present invention.

5 is a configuration diagram of a ferroelectric liquid crystal element used as an optical shutter for selecting display light in FIG.

FIG. 6 is a diagram illustrating a device configuration and an operation according to an embodiment of the present invention.

[Explanation of symbols]

1: light source for 3D image display element (backlight), 2: liquid crystal element (optical shutter for selecting display light, ferroelectric liquid crystal display element), 2a: opening, 2b: light shielding part, 3: display for 3D image display Element, 4a, 4b: distance measuring device, 10a, 10
b: insulating layer, 11a, 11b: glass substrate, 12a, 1
2b: transparent electrode, 13a, 13b: alignment control film, 14:
Spacer, 15: adhesive resin, 16: sealant, 17:
Liquid crystal layer, 18: injection port, 19: insulating layer, 30a, 30
b: display element substrate from glass substrate to alignment control film, 3
1: Smectic layer, 32: C1 orientation, 33: C2 orientation, 34: Lightning defect, 35: Hairpin defect.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshinari Yoshino 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tatsumi Ozaki 3- 30-2 Shimomaruko, Ota-ku, Tokyo (72) Inventor Yoshinori Shimamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hidekatsu Arai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A transmissive image display element capable of displaying a binocular image including a left-eye image element and a right-eye image element, a light source for illuminating the image display element from behind, and the image display element. The light source disposed between the light source and the light source passes through the image element for the left eye on the image display element and reaches the observer's right eye position. A parallax barrier that blocks light rays reaching the left eye position of the observer, and a liquid crystal element is used for the parallax barrier in a stereoscopic image display device that displays a three-dimensional image by a parallax stereogram method. A stereoscopic image display device characterized by the above-mentioned. 2. The apparatus according to claim 1, further comprising: a position measuring unit for the observer; and a control unit for controlling the positions and areas of the light transmitting unit and the light shielding unit of the liquid crystal element according to the position of the observer. The stereoscopic image display device according to claim 1. 3. The three-dimensional image according to claim 1, wherein the two-dimensional image and the three-dimensional image can be displayed simultaneously by changing the areas of the light transmitting part and the light shielding part of the liquid crystal element. Display device. 4. The three-dimensional image display device according to claim 1, wherein said liquid crystal element is a ferroelectric liquid crystal display element. 5. The ferroelectric liquid crystal of the liquid crystal display element has a pretilt angle of α, a cone angle of 2 °, an apparent tilt angle of θa, and an inclination angle of the smectic layer of δ <α + δ. 5. The three-dimensional image display device according to claim 4, wherein the three-dimensional image display device has an orientation state satisfying a relationship of Θ>θa> Θ / 2. 6. A pixel for forming a light transmitting part and a light shielding part of the liquid crystal element, wherein a width of the pixel is smaller than one third of a picture element in the image display element.
The stereoscopic image display device according to any one of the above.