JPH0634969A - Liquid crystal television device - Google Patents

Abstract

PURPOSE:To obtain the liquid crystal television device which easily provides stereoscopy without requiring spectacles which has a shutter mechanism which can be synchronized with two projecting devices and a screen. CONSTITUTION:A polarizer 2, a transparent electrode 4a, liquid crystal 5, a transparent earth electrode 4b, and a color filter 7 are laminated and inserted and held between glass plates 1a and 1b in order from a light incidence side, and an analyzer 3 is arranged on the light beam projection side of the glass plate 1b. Further. lambda/2 plates (polarizing member) are arranged inside cover glass 6 opposite alternate pixels 9. The lambda/2 plates 8 may be checkered or arranged in stripes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal television device capable of stereoscopic viewing.

[0002]

2. Description of the Related Art Conventionally, as a method for obtaining a stereoscopic image, there are a lenticular method, a color separation method, a polarization method and the like. Also, on a CRT (cathode ray tube) screen, two images are displayed with a temporal shift, and glasses with a shutter mechanism that can be synchronized with the screen are worn to observe each image separately with the left and right eyes. A method is known that enables stereoscopic vision by doing so.

On the other hand, in recent years, research and development of a liquid crystal display element has progressed, and a television device using this liquid crystal display element is in the stage of practical application. FIG. 2 is a schematic sectional view showing a configuration of a screen portion of a conventional liquid crystal television device. In the figure, glass plates 101a, 101b
Between the light beam incident side, the polarizer 102, the transparent electrode 104a, the liquid crystal 105, the transparent earth electrode 104b, and R.
The G and B color filters 107 are sequentially stacked and sandwiched. Further, an analyzer 103 is arranged on the light beam emission side of the glass plate 101b, and the outside thereof is protected by a cover glass 106. In the figure, color filter 10
7 are arranged in a repeating unit of R, G, B, and three (R, G, B) color filters 107 are arranged on one pixel 9.

The liquid crystal display element shown in FIG. 2 is a TN.
It is called (Twisted Nematic) type, and electrode 1
In the state where no voltage is applied to 04a and 104b, the liquid crystal 10
The major axis of the molecule of 5 is shifted by 90 degrees on the incident side and the emitting side. The light beam incident from the direction of the arrow in the figure becomes linearly polarized light that vibrates in one direction by the polarizer 102, enters the liquid crystal 105, and its vibrating surface shifts as the liquid crystal molecules twist, and when it exits the liquid crystal, the vibrating surface. Will be shifted by 90 degrees. The analyzer 103 is arranged so as to pass only the light whose vibration plane is displaced by 90 degrees, and the light beam passes through the analyzer 103.

On the other hand, when a voltage higher than a certain level is applied to the electrodes 104a and 104b, the liquid crystal molecules are tilted in one direction by the action of the electric field, and the above-mentioned 90-degree twist relationship is broken. Therefore, the vibrating surface of the light beam from the polarizer 102 does not shift by 90 degrees, and therefore the light beam cannot pass through the analyzer 103. Then, the amount of light passing through the analyzer changes depending on the applied voltage.

That is, by selectively applying a voltage to the electrodes 104a and 104b, a brightly visible portion and a darkly visible portion can be created and an image can be displayed. In the example of FIG. 2, R, G, B is assigned to each pixel as described above.
Since the color filter 107 is arranged, a color image is displayed.

[0007]

However, in the prior art as described above, there were the following problems in realizing stereoscopic vision in a liquid crystal television device. That is, the color separation method and the polarization method described above obtain a stereoscopic image by projecting each image from two screen projection devices in a moving image, but the two projection devices are a liquid crystal television. It is not realistic at present to equip the device because the device becomes very large.

Further, as in the conventional CRT screen method, it is indispensable to wear glasses having a shutter mechanism capable of synchronizing with the screen in the method of observing each image separately with the left and right eyes in terms of time. Therefore, in order to obtain the synchronization signal, the eyeglasses must be connected to the television device by an electric wire or the like. Therefore, inconveniently, expensive glasses are required and the range of movement of the observer is limited by the length of the wires.

The present invention has been made in view of the above points, and does not require two projectors or glasses having a shutter mechanism that can be synchronized with the screen, and can easily realize stereoscopic viewing. It is intended to provide a John device.

[0010]

According to another aspect of the present invention, there is provided a liquid crystal television device having a display screen in which a plurality of pixels composed of liquid crystal display elements are two-dimensionally arranged. In order to achieve the above, the polarization state of the light beam emitted from each pixel on the display screen is such that the polarization state of the light beam emitted from each pixel is orthogonal to at least one adjacent pixel in at least one arrangement direction. Is provided with a polarizing member for controlling.

According to another aspect of the liquid crystal television device of the present invention, the polarizing member is a λ / 2 plate, and the polarizing members are arranged in a checkerboard pattern corresponding to the two-dimensionally arranged pixels. In the television device according to a third aspect of the present invention, the polarizing member is a λ / 2 plate, and the polarizing members are arranged in stripes corresponding to the two-dimensionally arranged pixels.

[0012]

In order to stereoscopically view an image displayed on a plane, at least two images forming the stereoscopic image must be observed simultaneously or independently by the left and right eyes within a time considered to be simultaneous.

Therefore, in the present invention, focusing on the fact that the light beam passing through the liquid crystal display screen is polarized light in which the vibration directions are aligned in one direction, λ / 2 is formed outside the analyzer (exit side). By providing a polarizing member such as a plate, P-polarized light and S-polarized light can be obtained.
The structure is such that two images by polarized light are simultaneously formed on the screen.

In order to realize stereoscopic vision in the present invention,
A screen displaying a P-polarized image and an S-polarized image at the same time
It can be observed directly or by projecting it on a screen and observing it with the left and right eyes through the polarizing plates whose directions are deviated by 90 degrees. As a result, the observer independently sees only the image of one polarization with each of the left and right eyes (when the P-polarized image is viewed with the left eye, the S-polarized image is viewed with the right eye).
The two images are combined and recognized as a stereoscopic image.

However, in the present invention, stereoscopic viewing is possible by simply adding a polarizing member to the conventional display screen and wearing simple polarizing glasses independent of the device. Further, since the light beam passing through the liquid crystal display screen is polarized in one direction as described above, there is almost no loss of light amount in the polarizing member. Therefore, the display screen can be used as it is even when stereoscopic viewing is not required.

Further, in the liquid crystal display screen, since the video signal is directly applied to each pixel, there is no concern that the P-polarized screen and the S-polarized screen are confused. In addition, P-polarized image and S
Separately displaying a polarized image or displaying it as a normal plane image can be easily handled electrically, and one device can appropriately switch between a stereoscopic image and a plane image for observation. it can.

[0017]

1 is a schematic sectional view of a screen portion of a liquid crystal television device according to an embodiment of the present invention. In the figure, between the glass plates 1a and 1b, a polarizer 2, a transparent electrode 4a, a liquid crystal 5, a transparent earth electrode 4b, R
The color filters 7 of G and B are laminated and sandwiched in order, and the analyzer 3 is provided on the light beam emission side of the glass plate 1b.
Are arranged.

The above construction is the same as that of the conventional example shown in FIG. 2, but in this embodiment, the λ / 2 plate (polarizing member) 8 is provided inside the cover glass 6 arranged outside the glass plate 1b. It is arranged so as to correspond to every other pixel. This λ /
The arrangement of the two plates 8 will be described later in detail. Further, in the figure, the color filters 7 are arrayed in a repeating unit of R, G, B, and three (R, G, B) color filters 7 are arranged on one pixel 9.

The liquid crystal display element in this embodiment is of the same type as the TN type described with reference to FIG.
With no voltage applied to a and 4b, the long axes of the molecules of the liquid crystal 5 are shifted by 90 degrees on the incident side and the emitting side.
The light beam incident from the direction of the arrow in the figure becomes linearly polarized light that vibrates in one direction by the polarizer 2, enters the liquid crystal 5, and its vibrating surface shifts as the molecules of the liquid crystal twist, and when leaving the liquid crystal, the vibrating surface Will be shifted by 90 degrees. The analyzer 3 is arranged so as to pass only the light whose vibration plane is displaced by 90 degrees, and the light beam passes through the analyzer 3. At this time, in the present embodiment, λ / 2 corresponding to every other pixel 9.
Since the plate 8 is arranged, the vibrating surface of the light beam that has passed through the λ / 2 plate 8 is further converted by 90 degrees.

On the other hand, when a voltage higher than a certain level is applied to the electrodes 4a and 4b, the liquid crystal molecules are tilted in one direction by the action of the electric field, and the above-mentioned twist relationship of 90 degrees is broken. Therefore, the vibrating surface of the light beam from the polarizer 2 is not displaced by 90 degrees, and therefore the light beam cannot pass through the analyzer 3. This is the same as the conventional example of FIG.

In the above structure, the liquid crystal 5 and λ / 2
It is desirable that the distance between the plates 8 be as small as possible.
If this distance is too large, parallax may occur when the screen is obliquely observed, and the polarization direction of the light beam from each pixel 9 may not be as intended.

The position of the color filter 7 is not limited to the position between the electrode 4b and the glass plate 1b shown in FIG.
However, the positional relationship between the analyzer 3 and the λ / 2 plate 8 must be in the order of the analyzer 3 / λ / 2 plate 8 from the incident side.

Now, the arrangement of the λ / 2 plate (polarizing member) 8 will be described with reference to FIGS. 3, 5 and 6. First, FIG. 3 is an example in which the λ / 2 plate 8 is arranged on the checkered grid corresponding to the pixels 9, and the light beams emitted from each pixel are arranged in two array directions (vertical direction of the screen 10). And adjacent pixels) are adjacent to each other and are orthogonal to each other. That is, as shown in the drawing, the P-polarized pixel and the S-polarized pixel are repeated in two directions. Although not shown in FIG. 2, the color filter 7 is arranged so as to repeat R, G, B in the vertical direction or the horizontal direction.

Next, in FIG. 5, the λ / 2 plate 8 is vertical (vertical direction).
In this example, the P-polarized pixel rows and the S-polarized pixel rows are alternately repeated in the horizontal direction. In the example of FIG. 3 described above, the polarization directions are orthogonal to each other in the pixels adjacent to each other in the vertical and horizontal directions.
As shown in (3), stereoscopic viewing is possible even if pixels adjacent to each other in only one direction have their polarization directions orthogonal to each other.

In the striped arrangement of FIG. 5, the color filters 7 can be arranged in either (A) or (B). That is, R, G, B may be repeated in the horizontal (left and right) direction, or R, G, B in the vertical direction.
It may be repeated.

Next, in FIG. 6, the λ / 2 plate 8 is in the horizontal direction (left-right direction).
In this example, the P-polarized pixel rows and the S-polarized pixel rows are alternately repeated in the vertical direction. In the arrangement of FIG. 6 as well, the arrangement of the color filters 7 can be either (A) or (B). That is, R, G, B may be repeated in the horizontal direction, or R, G, B may be repeated in the vertical direction.

Next, FIG. 4 shows a modification of the embodiment shown in FIG. The screen of the liquid crystal television device shown in FIG. 4 has the same basic structure as that of FIG. 2, except that the glass plate (1b in FIG. 3) on the exit side is omitted. In this way, by omitting the glass plate on the injection side,
The distance between the liquid crystal 5 and the λ / 2 plate 8 can be reduced,
The parallax between the pixel 9 and the λ / 2 plate 8 can be reduced. Therefore, a good stereoscopic image can be observed even from an angle. In this case, the cover glass 6 may be made slightly thicker,
It is desirable to secure strength.

In the above liquid crystal television device,
In order to realize stereoscopic vision, the left eye and right eye each have an azimuth of 9
It is sufficient to observe by wearing glasses having polarizing plates that are offset by 0 degree. As a result, the observer independently sees only the image of one polarized light with the left and right eyes, and the two images are combined and recognized as a stereoscopic image.

Further, in addition to directly observing the screen, the screen is projected on the screen (that is, the above-mentioned television device is used as a projector), and the projected image is observed through the above-mentioned polarized glasses. It may be done.

In the above embodiments, the liquid crystal color television device has been described as an example, but it goes without saying that the present invention is also applied to a monochrome television device. or,
Although the λ / 2 plate is used as the polarizing member in the above-mentioned embodiment,
The polarizing member is not limited to the λ / 2 plate. Further, the liquid crystal display element itself is not limited to the above-mentioned TN type, but may be a DS (dnamic Scattering) type, a GH (Guest-Hos
Other types such as t) type may be used.

[0031]

As described above, in the present invention, the polarization member is arranged on the display screen, and the polarization state of the light beam emitted from each pixel is orthogonal to each other in at least one array direction. Thus, it is possible to display two images of P-polarized light and S-polarized light on the screen at the same time without the need for two projection devices or the like. Then, stereoscopic viewing is possible only by using polarized glasses that are independent of the device, and glasses with a connector having a shutter mechanism that can be synchronized with the screen are not necessary. That is, according to the present invention, stereoscopic image viewing can be realized much more easily than in the past. Also, P
Separately displaying the polarized and S-polarized screens and displaying a normal plane image can be easily performed by electrical switching, and there is almost no loss of light amount due to the polarizing member. The three-dimensional image and the two-dimensional image can be appropriately observed with the television device.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a screen portion of a liquid crystal television device according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a screen portion of a conventional liquid crystal television device.

FIG. 3 is a schematic diagram for explaining an arrangement example of polarizing members in an example of the present invention.

FIG. 4 is a schematic cross-sectional view showing a modified example of the embodiment of FIG.

FIG. 5 is a schematic diagram for explaining an arrangement example of a polarizing member in an example of the present invention.

FIG. 6 is a schematic diagram for explaining an arrangement example of a polarizing member in the example of the present invention.

[Explanation of symbols]

1a, 1b ... Glass plate, 2 ... Polarizer, 3 ... Analyzer, 4
a, 4b ... Transparent electrodes, 5 ... Liquid crystal, 6 ... Cover glass, 7
... Color filter, 8 ... λ / 2 plate (polarizing member), 9 ...
Pixel, 10 screens.

Claims (3)

[Claims] 1. A liquid crystal television device comprising a display screen in which a plurality of pixels each comprising a liquid crystal display element are two-dimensionally arranged, wherein the display screen shows a polarization state of a light beam emitted from each pixel. A liquid crystal television device comprising a polarizing member for controlling a polarization state of a light beam emitted from each pixel so that adjacent pixels are orthogonal to each other in at least one array direction. 2. The polarization member is a λ / 2 plate,
2. The liquid crystal television device according to claim 1, wherein the liquid crystal television device is arranged in a checkered pattern corresponding to the pixels arranged in a dimension. 3. The polarization member is a λ / 2 plate,
2. The liquid crystal television device according to claim 1, wherein the liquid crystal television device is arranged in stripes corresponding to the pixels arranged in a dimension.