JPH0198383A - Display device - Google Patents

Abstract

PURPOSE:To contrive to improve the apparent resolution with simple constitution by providing a double refraction panel and a polarized switch in front of the display device main body. CONSTITUTION:The display device consists of a display device main body 1 obtaining an optical image on the index color cathode ray tube, for example, a double refraction panel 2 and a polarized switch 3 provided in front thereof. The optical image obtained by the display device main body 1 is transmitted through the double refraction panel 2, and the 1st optical image obtained by the double refraction and the 2nd optical image due to abnormal light are obtained and each picture element of the 1st and 2nd optical images is selected to be a location complementary to each other and observed by using the polarized switch 3 through sequential changeover.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a display device, for example, a display device that displays various types of moving images, still images, characters, graphics, etc.

(Summary of the Invention) The present invention provides a birefringent panel in combination with a display device main body used as a normal display device such as a cathode ray tube type or a liquid crystal type, and utilizes the birefringence to distinguish between ordinary light and extraordinary light. By extracting the optical images of , and selectively displaying them with their positional relationship set to a positional relationship that complements each other, it is possible to display an optical image with a resolution higher than that of the display device main body.

[Conventional technology]

Various display devices Various display devices such as cathode ray tube display devices and liquid crystal display devices have been proposed and put into practical use. With the increasing demand for high-definition cathode ray tubes, development of high-definition cathode ray tubes, etc. is active.

However, in the case of cathode ray tubes, for example, there are limits to the miniaturization of the phosphor surface, and limits to the reduction of the spot size on the phosphor surface for electron beam irradiation. be.

On the other hand, cathode ray tube type display devices that can avoid image shaking under strong external light or due to vibrations, etc. are equipped with shadow masks and apertures that face the fluorescent surface and set the landing position of the electron beam on the fluorescent surface. It is not equipped with a means for determining the position of the electron beam such as a grill,
Cathode ray tube display devices of the beam index type have been attracting attention because they can make effective use of electron beams, that is, produce bright images, and can avoid shaking of the screen caused by the photographing of the electron beam position determining means.

However, in a cathode ray tube display device using such a beam index method, since the beam spot size is determined by the cross-sectional diameter of the electron beam itself because it does not have a means for determining the electron beam position, the beam spot size on the fluorescent surface is determined by the cross-sectional diameter of the electron beam itself. There is a problem in increasing the resolution because there are restrictions on reducing the spot size and strict restrictions on the index frequency band.

[Problem that the invention seeks to solve].

The present invention provides a display device that solves the constraints of increasing resolution in the various display devices described above.

[Means for solving problems]

As shown in FIG. 1 or 2, the present invention comprises a display device main body (1) that obtains an optical image, which is composed of, for example, a color cathode ray tube using an ordinary index method, and a birefringent panel (1).
2) and a polarization switch (3), the optical image obtained by the display device main body (1) is transmitted through a birefringence panel (2), and a first optical system using ordinary light obtained by the birefringence of the panel (2). A positional relationship in which each pixel of the first and second optical images complements each other, i.e., a relationship in which one optical image is obtained by combining both optical images, for example. Further, the display device main body (1) sequentially switches and displays an original first display optical image displayed by the Pii element of the display device body (1) and a second display optical image that complements this first display optical image. In response to this switching, the polarization switch (3) switches between the first and second optical images for observation.

(Function) - In the above-described device of the present invention, the display device main body (1) is, for example, a color cathode ray tube using a beam index method, and its phosphor surface has phosphor stripes of each color, e.g., red, green, and blue, in a vertical direction. To explain the case where the configuration is arranged alternately and sequentially in the horizontal direction so as to extend to
For example, in the display device main body (11), as shown in FIG.
G, B, R.

In the case of displaying an optical image in which G, B... are arranged alternately, in this case, this one optical image is
Figure 3B1 by passing through the birefringence panel (2)
As shown in the image Ro under ordinary light.

The first optical image (11) due to the arrangement of Go, Bo, Ro, Go, etc. and the first optical image due to the extraordinary light shown in FIG.
Each pixel Rex, G E! deviated by the required deviation amount S from the optics @(11). X+ B ex, Rex,
G ex.

A second optical image (12) is obtained by the arrangement of Bex.... And these first and second optics 11! (11) and (12) have a polarization plane of 90°
The polarization switch (3) allows them to be separated by 90° from each other.
If the rotated polarized optical images (11) and (12) are selectively transmitted, either one of the optical images (11) or (12)
can be selectively observed. Therefore, for example, the optical image (11
) constitute the pixels Ro and Go.

With respect to the arrangement pitch P of Bo, Ro..., the deviation of the extraordinary light (assuming 1s is -P, as shown in FIG. 382,
Adjacent pixels ReX forming the second optical image (12),
The set (triplet) of Q ex and B ex is the third
They are arranged between each pixel of the triplet of ordinary light pixels Ro, Go, and Bo in FIG. B1, and when these triplets are viewed as a whole, within one pitch P, there is a RO-Bex-Go triplet and a Go-Rex-B.

There will be two sets of triplets, and the apparent resolution will be doubled. In the device of the present invention, the display is performed using the pixels R, G, and B described in FIG. 3 A1 in the display device main body (11). It has a complementary relationship with the optical image of 1.
In other words, when obtaining the first and second optical images using ordinary light and extraordinary light as explained in FIG. 381 and B2, the first display section is as shown in FIG. Display pixels R1, GL, B1, etc. are displayed using display signals based on the original optical image using each pixel R, G, B... R2* G2 rB2 ... is displayed, and in response to switching between the first and second display optical images, the polarization switch (3) sequentially displays
Each optical image (11) and (12) shown as 1 and B2
If these are observed alternately, it is possible to observe an optical image whose apparent resolution is doubled due to the combination of the first and second optical images (11) and (12).

〔Example〕

An example of the apparatus of the present invention will be explained with reference to FIG. In this example, a color cathode ray tube using a beam index method, for example, is used as the display device body (1), and in this case, a birefringent panel (2) is installed opposite the front panel (1a) having a fluorescent surface. establish. A polarization switch (3) is placed on the viewer's side, facing the birefringence panel (2).

For example, a liquid crystal birefringence panel can be used as the birefringence panel (2). FIG. 4 shows the basic structure of this liquid crystal birefringent panel. In this case, the liquid crystal ( 23) is filled. The molecules of this liquid crystal (23) are aligned so as to be tilted as schematically shown in the figure.

When light enters the liquid crystal birefringent panel (2) having such a structure, as shown by arrow a, birefringence occurs due to the anisotropy of the refractive index of the liquid crystal molecules, and as shown by arrow bo in the figure. Ordinary light and extraordinary light shown by arrow beX are generated. In this case, if the amount of deviation between the ordinary light bo and the extraordinary light bex when emitted from the birefringent panel (2) is S, S is given by the following equation.

Here, a=1/rllll b=1/n//+ C
2=a2sin2θ+b2cos2θ However, on n: refractive index in the short axis direction of the liquid crystal molecule nN: refractive index in the long axis direction of the liquid crystal molecule θ: tilt angle of the liquid crystal molecule with respect to the normal to the panel (4) e: of the liquid crystal (23) It becomes thick. In this case, the ordinary light and the extraordinary light have different polarization states, and are linearly polarized lights that are orthogonal to each other by 90 degrees.

The polarization switch (3) has a liquid crystal device (31) on the side facing the birefringence panel (2) that has the effect of rotating the polarization axis.
and a polarizer (32).

Figures 5A and 5B show the configuration and operation of the liquid crystal device that constitutes the polarization switch (3).
31) is a pair of transparent substrates (41) and (42A) having transparent electrodes (41A) and (42A) on their inner surfaces, respectively.
), and for example, twisted nematic liquid crystal (hereinafter referred to as TNCL) (43) is filled between the two.

Transparent counter electrodes (4) in transparent substrates (41) and (42)
A power supply (44) is connected between 1A) and (42A), and when the power supply (44) is off, the alignment axis of the liquid crystal (43) is twisted by 90 degrees to change the incident polarized light, as shown in FIG. 5B, for example. It has the effect of rotating the light by 90 degrees, and when the power source (44) is on, as shown in FIG.
32), by turning on and off the power supply (44), for example, mutually orthogonal polarized light, ie, either the above-mentioned ordinary light or extraordinary light, can be switched and extracted.

Therefore, as explained in FIG. 3, in order to obtain one predetermined screen on the display device body (1), in the first section, the first display optical image as the pixel RIGIB1 . . . explained in FIG. At this time, for example, by turning on the polarized light switch (3), only the first optical image (11) due to ordinary light as explained in FIG. A second display optical image of image R2G2B2 . . . is projected and displayed, and at this time the polarization switch (3
), for example, the optical image of the extraordinary light (1
Only 2) can be taken out. Therefore, if the first and second display optical images are projected on the display device main body (1) and switched by the polarization switch (3), the first optical image (11) due to ordinary light and the second optical image due to extraordinary light are displayed. The two optical images (12) can be taken out sequentially and alternately, and these images are complementary to each other, and images with apparently twice the resolution can be observed.

In the example shown in Figure 1, the birefringent panel (2)
This is a case where the first and second optical images (11) and (12) are taken out by the polarization switch (3) from two types of polarized optical images obtained by the birefringence effect. As shown in Figure 2, the display device body (
Polarization switch (3) between 1) and birefringent panel (2)
It is also possible to adopt a configuration in which . In this case, the polarizer (32) of the polarization switch (3) is placed on the incident side,
A liquid crystal device (31) for rotating the polarization axis is arranged on the rear stage side. That is, in this case, the display device main body (1)
The optical image obtained by linearly polarizing the optical image from the polarizer (32) is switched to a 90° rotated or unrotated optical image by switching the liquid crystal device (31) of the polarization switch (3), and then converted into an ordinary light image by a birefringent panel. and a second optical image (12) based on the extraordinary light.

As an actual example, if the original pixel pitch P of the display device main body (1) is 0.42 mm, then S = 0.21
To obtain mm and double the pixel apparently, n //=
1.75゜n r = 1.50. θ==70°
+8=1.9mm.

In order to obtain the above-mentioned required amount of deviation S, the birefringent panel (2) is not limited to the selection of the orientation angle θ. It is also possible to obtain a desired offset position by tilting the device at a desired angle.

Furthermore, it is advantageous to use a liquid crystal panel as the birefringent panel (2) because a large-area panel can be constructed relatively easily and inexpensively, but it may also be made of calcite, quartz, or the like.

Furthermore, as the liquid crystal device (31) of the polarization switch (3), it is also possible to use, for example, a π cell, which has a faster switching speed than the above-mentioned TNCL.

In addition, the display device main body (1) is not limited to a color cathode ray tube using an index method, but can also be used to further increase the apparent resolution by using a cathode ray tube that uses an ordinary shadow mask or an aperture grill. Alternatively, various display devices such as a liquid crystal display device can also be used.

〔Effect of the invention〕

As described above, in the present invention, the apparent resolution can be improved by simply providing the birefringent panel (2) and the polarization switch (3) in front of the display device body (11) such as a normal cathode ray tube or liquid crystal display device. Therefore, a high-resolution display device can be obtained with a simple configuration.

Further, by using a sufficiently bright display device main body (1) such as a color cathode ray tube using a beam index method, it is possible to observe a sufficiently bright and high-resolution, high-quality image.

Furthermore, as described above, according to the present invention, the structure is such that the birefringent panel (2) and the polarization switch (3) are provided in front of the normal display device main body (1). (2) and a polarization switch (3) are introduced to the front surface of the display device body, and have the effect of reducing the amount of external light that is reflected from this and directed towards the viewer, preventing contrast reduction due to external light as in the conventional case. Since it is possible to effectively avoid the reduction in contrast due to external light by omitting the special installation of filters etc. to prevent this, it is especially useful for display devices used in airplanes where contrast with external light is a problem, allowing viewers to immediately view images. It can provide the practical benefit of being readable.

[Brief explanation of the drawing]

Figures 1 and 2 are configuration diagrams of each side of the device of the present invention;
The figure is an explanatory diagram of the observed optical image, FIG. 4 is a basic configuration diagram of a liquid crystal birefringence panel, and FIGS. 5A and 5B are explanatory diagrams of a polarization switch. (1) is the display device main body, (2) is the birefringent panel, (3)
is a polarization switch.

Claims (1)

[Scope of Claims] A display device main body for obtaining an optical image, a birefringent panel, and a polarization switch, the optical image being transmitted through the birefringent panel to form a first optical image by ordinary light from the birefringent panel. and a second optical image caused by extraordinary light are taken out so that each pixel of the first and second optical images has a mutually complementary positional relationship, and the display device main body is used to display images by the pixels of this display device main body. The original first display optical image to be displayed and the second display optical image that complements this optical image are sequentially switched and displayed, and in response to this switching, the first and second optical images are changed by the polarization switch. A display device characterized by switching observation.