JP2786930B2 - Small display device - Google Patents

Description

The present invention relates to a small display device suitable for various electronic devices such as a computer and a video tape recorder.

(B) Conventional technology At present, the above-mentioned display devices for electronic devices have been showing various trends in terms of enlargement and thinning, and one of the trends is personalization.

As an example of such a small-sized display device for personal use, a device mounted on a user's head and used has been proposed in Japanese Patent Application Laid-Open No. S59-117876 [H04N5 / 64]. That is, in this conventional example, an optical system such as a small liquid crystal panel (23) and a magnifying lens (24) as shown in FIG. 6 is built in a goggle-shaped display device main body (21) shown in FIG. At least, an enlarged virtual image (28) of the image (27) on the panel is observed by the lens (24). In FIG. 6, (25) shows an optical path changing light prism, and (13) shows the eyes of a user (26).

(C) Problems to be Solved by the Invention Since the above-mentioned conventional example is a monochrome display using one single-color liquid crystal panel, it is conceivable to make these colors. At that time, if one liquid crystal panel with built-in R (red), G (green), and B (blue) stripe filters is used,
It seems that color display can be realized relatively easily.

However, in order to realize a color image with sufficiently high resolution by such a method, a liquid crystal panel having a high density and a high number of pixels is required.
(Approximately inches), there is a drawback that the production is extremely difficult, and that the light transmittance is greatly reduced and sufficient luminance cannot be obtained.

Therefore, an object of the present invention is to provide a small display device which can obtain high luminance and high resolution and can be sufficiently reduced in size for personal use.

(D) Means for Solving the Problems In the display device of the present invention, three transmissive liquid crystal panels equipped with RGB filters, respectively, and R and B reflecting surfaces are combined to combine the transmitted light of the panels. And a magnifying lens means for reflecting the output light of the prism means.

(E) Operation With the above configuration, the transmitted light from each of the liquid crystal panels is combined by the prism means, and an enlarged image of the combined color image by the lens means is observed.

(F) Embodiment FIGS. 1 to 3 show an embodiment of a small display device according to the present invention. FIG. 1 is a schematic view showing the principle of operation, (1) is a transmissive liquid crystal panel having an R filter mounted on its front surface, and (2) and (3) are similarly mounted with a B filter and a G filter. (4), (5), and (6) are cold cathode flat fluorescent lamp-type backlights disposed on the back of each liquid crystal panel.
(7) is that the three incident surfaces are on each of the above liquid crystal panels (1)
(2) A prism means for color synthesis arranged opposite to (3), and (12) is a convex lens for enlargement arranged on the exit surface thereof.

As shown in FIG. 2, the prism means (7) comprises four triangular prisms (8) having a cross section of an isosceles triangle.
To (11) are adhered to each other, and an R reflection film is formed on one joint surface (8a) of the first prism (8).
A B reflection film is formed on one of the joining surfaces (9a) of the prism (9), and the joining surface (11) of the fourth prism (11) is further formed.
a) A B-reflection film and an R-reflection film are formed on (11b), respectively, and both joining surfaces (10a) (10
b) has a structure in which no reflective film is formed. Each of these prisms (8) to (11)
Is adhered with a transparent adhesive having a refractive index substantially the same as that of the prism.

Therefore, according to this structure, as can be seen from FIG. 1, the R-transmitted light from the liquid crystal panel (1) receives the bonding surface (8a) of the first prism (8) or the bonding surface (8) of the fourth prism (11). 11b) is reflected by the fourth prism (11) and exits,
The B transmitted light from the liquid crystal panel (2) is transmitted to the second prism (9).
(9a) or the fourth prism (11).
The light reflected by a) is emitted from the fourth prism (11), and the G transmitted light from the liquid crystal panel (3) is transmitted to the third and fourth prisms (10).
The light goes straight through (11) and exits from the fourth prism (11).

At this time, the liquid crystal panels (1), (2), and (3) are accurately positioned and attached to the respective entrance surfaces of the prism means (7) such that the optical axes at the emission ends of the RGB transmitted light coincide with each other. Therefore, the respective transmitted lights are combined, so that the color image (14) by the liquid crystal panels (1), (2), and (3) appears on the exit surface of the fourth prism (11). Then, when this color image is incident on the convex lens (12), a color enlarged image (15) is observed.

Each of the liquid crystal panels (1), (2), and (3) is driven by a well-known method employed in a normal liquid crystal television.
If the direction of arrow A in FIG. 1 is the vertical scanning direction of the liquid crystal panel (3), the vertical scanning directions of the liquid crystal panels (1) and (2) are opposite to each other as shown by arrows B and C, respectively. .

FIG. 3 shows two units (20) composed of a liquid crystal panel, a backlight and prism means configured as described above.
FIG. 5 shows an example in which (20) is incorporated into a goggle-shaped display device body (21) as in the conventional example (FIG. 5) so as to face the left and right eyes together with the lenses (12) and (12). )(twenty two)
Is a built-in headphone. In addition, the units (20) and (20) also have a built-in drive circuit for each liquid crystal panel, but these are not shown.

The units (20) and (20) can observe a color stereoscopic image by providing video signals having slightly different phase differences to each liquid crystal panel.

FIG. 4 shows another embodiment which replaces FIG. 1. The same reference numerals are given to the portions corresponding to FIG. 1 and the description will be omitted. In this embodiment, the prism shown in FIG. The means (7) includes a first prism (16) having an R reflection film formed on a bonding surface (16a), a second prism (17) having a B reflection film formed on a bonding surface (17a), and a bonding surface ( 18a) and a third prism (18) having no reflective film formed thereon.

(G) Effects of the Invention According to the present invention, high-luminance and high-resolution color images can be realized by using three liquid crystal panels dedicated to RGB and prism means for color synthesis, and furthermore, for personal use. As a result, it is possible to provide a small display device that can be sufficiently reduced in size.

[Brief description of the drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a schematic diagram showing the principle of operation, FIG. 2 is a perspective view showing a main part of the unit, and FIG. FIG. FIG. 4 is a schematic diagram showing the operation principle of another embodiment. 5 and 6 show a conventional example, FIG. 5 is a schematic view showing the principle of operation, and FIG. 6 is a plan view showing a state in which the display device is mounted on the head in partial cross section. (1) (2) (3): liquid crystal panel, (4) (5)
(6): backlight, (7): prism means, (8)
(9) (10) (11): prism, (12): convex lens for magnification

Claims (1)

(57) [Claims] 1. A transmissive liquid crystal panel in which RGB filters are respectively mounted on a front surface and arranged in three different directions, a backlight mounted on a back surface of each of the filters, and a plurality of combined liquid crystal panels. An R-reflection surface and a B-reflection surface formed on a part of the prism, and a prism means for color synthesis including each of RGB input surfaces and one output surface facing each of the liquid crystal panels; and an output surface side of the prism device. And a magnifying lens means on which synthetic output light emitted from the emission surface is incident, and a synthetic color magnified virtual image of an image displayed on the liquid crystal panel is observed through the lens means. Small display device.