JPH05216004A - Projection type projector - Google Patents

Abstract

PURPOSE:To obtain the video of a good contrast at the brightness meeting video software and ambient environment by arbitrarily adjusting an aperture diameter in an optical system. CONSTITUTION:A liquid crystal panel 33 consisting of a particulate/liquid crystal composite formed by dispersing particulates into a liquid crystal and electrode substrates arranged on both sides of this composite is used and the diameter of an aperture 35 placed on the axis of a projecting lens 36 is variable. The liquid crystal panel 33 consisting of a high polymer/particulate composite film formed by dispersing the liquid crystal into the high polymer and the electrode substrates disposed on both sides of this composite is used and the diameter of the aperture 35 placed on the axis of the projecting lens 36 is variable. Dichromatic dyes are preferably incorporated into the liquid crystal panel 33 and the size of the diameter of the aperture 35 is preferably variable in association with the illuminance of a place where a screen 37 of a projection type projector is installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type liquid crystal projector.

[0002]

2. Description of the Related Art A fine particle dispersion type liquid crystal electro-optical element and a polymer dispersion type liquid crystal electro-optical element are prepared by dispersing fine particles 14 in a liquid crystal 13 or in a polymer matrix 24 as shown in FIG. 23 is a special display body dispersed. These optical elements change from a light scattering state to a light transmitting state with the application of a voltage. Utilizing this property, application as a light valve of a projection type liquid crystal projector is also under study.

When these liquid crystal electro-optical elements are used as a projection type liquid crystal projector, a deflecting plate, which is required in the conventional liquid crystal electro-optical elements, is not required, and thus a bright display element may be obtained.

[0004]

In the conventional liquid crystal projection type projector, since a TN mode liquid crystal panel or the like is used, sufficient image quality cannot be obtained if the place where the image is viewed is bright. In other words, in order to watch software such as movies, you can concentrate on the video by darkening the whole room and watching it, while watching sports at home parties, live music, environment software, etc. It was inconvenient because I could not make it bright. On the other hand, projection type projectors that use liquid crystal electro-optical elements in the scattering-transmission mode will be brighter and will be able to project images in bright places, but since the projection lens will swallow scattered light, it can be used in dark rooms. However, the black display was not sufficient, and it was necessary to adjust the contrast by changing the F value and swallowing angle of the projection lens.

The present invention has been made in order to solve such a difficulty, and the purpose thereof is to be able to watch an image with sufficient brightness even in a bright room, and even in a dark place depending on software. The purpose is to provide means for displaying high-quality images.

[0006]

A projection type projector according to the present invention comprises: (1) a liquid crystal panel comprising a fine particle / liquid crystal composite in which fine particles are dispersed in a liquid crystal, and electrode substrates arranged on both sides of the composite. In the projection type projector using, the diameter of the aperture placed on the axis of the projection lens is variable.

(2) In a projection type projector using a liquid crystal panel composed of a polymer / liquid crystal composite film in which a liquid crystal is dispersed in a polymer and electrode substrates arranged on both sides of the composite film, the axis of the projection lens is used. It is characterized in that the diameter of the aperture placed above is variable.

(3) The liquid crystal panel is characterized by containing a dichroic dye.

(4) A matrix array of non-linear elements is arranged on at least one opposing inner surface of the electrode substrate, and the fine particle / liquid crystal composite and the polymer / liquid crystal composite film are driven by the non-linear element. To do.

(5) The non-linear element is a thin film field effect transistor whose main component of the semiconductor layer is single crystal silicon, amorphous silicon or polycrystalline silicon.

(6) The non-linear element is an element composed of a laminated body of a tantalum-based metal, an insulating film and a metal.

(7) The diameter of the aperture is variable by driving the electric motor.

(8) It is characterized in that the diameter of the aperture is variable in association with the illuminance of the screen installation place of the projection type projector.

[0014]

When the polymer dispersion type liquid crystal display device is used in the projection type projector, it is desirable to use the black display when the device is in the scattering state. In order to display black in this scattering state, it is desirable to reduce the diameter of the diaphragm placed at the focal point of the condenser lens. Further, in order to increase the brightness on the projection screen, it is desirable to enlarge the diaphragm. That is, the contrast and screen brightness can be set by adjusting the diameter of the diaphragm according to the diffused light component of the light source and the scattering characteristic of the polymer dispersed liquid crystal panel. By using a polymer-dispersed panel, it is possible to obtain about twice as much brightness on the screen as a TN liquid crystal panel. However, with respect to the contrast, the limit is about 100: 1 with respect to 200: 1 of the TN liquid crystal panel, and in order to further increase the contrast, the aperture diameter is reduced, and the screen brightness is reduced. On the other hand, however, a display screen in daily life of 30: 1 is sufficient at most. Rather, it is more inconvenient to darken the whole room in all video software.
From these things, being able to adjust the brightness and contrast according to the image software, the situation on the viewer side, and the environment is a great advantage. In other words, in a projection projector that uses a polymer-dispersed liquid crystal panel, the user can arbitrarily adjust the aperture of the optical system, or the aperture or sensor that automatically adjusts the brightness and contrast according to the surrounding environment. It is necessary to equip the projector with a drive unit for adjusting. By providing these devices, a wide selection of images can be obtained for the viewer.

[0015]

EXAMPLE In this example, a 1.5-inch TFT panel on which polymer dispersed liquid crystal was formed was used. In the optical system shown in FIG. 1, the swallowing angle of the lens of the diaphragm is + /
At -11.3 °, the brightness on the screen is 319
It was lm and the contrast was 3.19. A xenon lamp was used as a light source. I was able to fully watch the images such as letters in a bright room. Next, the aperture is changed to +/- 2.9 °, the brightness is 253 lm, and the contrast is 2
It was 5.4. At this level, when I darkened the room, I was able to fully watch the animation and other images.

[0016]

As described above, according to the present invention, even if the room is bright,
Even in the dark, a bright image with good contrast was obtained with a projector using a polymer dispersed liquid crystal panel.

[Brief description of drawings]

FIG. 1 is a drawing showing a configuration of a fine particle dispersion type liquid crystal electro-optical element.

FIG. 2 is a drawing showing a configuration of a polymer-dispersed liquid crystal electro-optical element.

FIG. 3 is a diagram showing a configuration of a projection type liquid crystal projector.

[Explanation of symbols]

 11 --- Glass substrate 12 --- Transparent electrode 13 --- Liquid crystal 14 --- Fine particles 15 --- Transparent electrode 16 --- Glass substrate 17 --- Fine particle dispersion type element 21 --- Glass substrate 22- --- Transparent electrode 23 --- Liquid crystal 24--Polymer matrix 25 --- Transparent electrode 26 --- Glass substrate 27 --- PDLC element 31 --- Light source 32 ---- Collimator lens 33 --- Scattering-transmissive liquid crystal panel 34 --- Condensing lens 35 --- Aperture 36 --- Projection lens 37 --- Screen

Claims (8)

[Claims] 1. A projection type projector using a liquid crystal panel comprising a fine particle / liquid crystal composite in which fine particles are dispersed in a liquid crystal and electrode substrates arranged on both sides of the composite, wherein the projection lens is placed on the axis of the projection lens. A projection type projector characterized by having a variable aperture diameter. 2. A projection type projector using a liquid crystal panel comprising a polymer / liquid crystal composite film in which a liquid crystal is dispersed in a polymer, and electrode substrates arranged on both sides of the polymer / liquid crystal composite film, on an axis of a projection lens. A projection type projector characterized in that the diameter of the aperture placed on it is variable. 3. The projection type projector according to claim 1, wherein the liquid crystal panel contains a dichroic dye. 4. A matrix array of non-linear elements is arranged on at least one opposing inner surface of the electrode substrate, and the fine particle / liquid crystal composite and the polymer / liquid crystal composite film are driven by the non-linear element. The projection type projector according to claim 1 or 2. 5. The projection according to claim 1, wherein the non-linear element is a thin film field effect transistor having a semiconductor layer of which main component is single crystal silicon, amorphous silicon or polycrystalline silicon. Type projector. 6. The projection type projector according to claim 1, wherein the non-linear element is an element composed of a laminated body of a tantalum-based metal, an insulating film, and a metal. 7. The diameter of the aperture can be changed by driving an electric motor.
The projection type projector according to 4, 5, or 6. 8. The size of the diameter of the aperture is variable in association with the illuminance of the screen installation place of the projection type projector.
The projection type projector according to 5, 6, or 7.