JPH05158039A - Projection type picture display device - Google Patents

Abstract

PURPOSE:To prevent a non-picture element part from being projected to a screen so as to improve image quality. CONSTITUTION:This device is provided with three liquid crystal panels 31R on which a picture which should be projected is displayed, a light source from which light is emitted, an optical system which separates the light from the light source to respective components to guide to the panels 31R and superposes the respective components transmitted through the panels 31R, a projecting lens which enlarges and projects the respective components transmitted through the panels 31R on the screen, and three transmission screens 60R which are set at a specified distance apart from the projection side transparent substrate 312R of the panel 31R. Then, the respective components transmitted through the panel 31R are formed into an image on the transmission screen 60R by a microlens 319R.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type image display device in which the image quality of an enlarged and projected image is improved.

[0002]

2. Description of the Related Art A conventional projection type image display device of this type will be described with reference to FIG. 2 is a schematic configuration diagram of the projection type image display device according to the present invention, the parts shown in the drawing are the same except that the transmissive screens 60R, 60G and 60B are provided, and therefore FIG. I shall explain. In such a projection type image display device, three liquid crystal panels 31R, 31G and 31B for dividing an image to be projected into three primary colors of R, G and B for display and a light source light L from a light source 10 for the liquid crystal panel 31R. , 31G, 31B corresponding to three components L
4 dichroic mirrors that decompose into R, LG, and LB
21a to 21d, two total reflection mirrors 22a to 22b, and a projection lens 40 for enlarging and projecting the light source light L transmitted through the three liquid crystal panels 31R, 31G, and 31B onto the screen 50.

[0003]

However, the above-mentioned conventional projection type image display device has the following problems. That is, in the liquid crystal panels 31R, 31G, 31B, a black matrix that blocks transmission of the light source light L is provided in a portion other than the pixel electrode so that the light source light L transmits only the pixel electrode. Therefore, the portion (non-pixel portion) corresponding to the black matrix is also enlarged and projected on the screen 50. Therefore, the higher the enlargement ratio, the worse the image quality of the non-pixel portion.

The present invention has been devised in view of the above circumstances, and provides a projection type image display device for improving the image quality by not projecting a portion corresponding to a black matrix, that is, a non-pixel portion on a screen. The purpose is to do.

[0005]

A projection type image display device according to the present invention comprises a liquid crystal panel on which an image to be projected is displayed, a light source for emitting light source light, and an optical system for guiding the light source light to the liquid crystal panel. An exit side transparent substrate of the liquid crystal panel, comprising a projection lens for enlarging and projecting the light source light transmitted through the liquid crystal panel onto the screen, and a transmissive screen installed at a predetermined distance from the exit side transparent substrate of the liquid crystal panel. An image forming lens corresponding to the pixel electrode is formed on the light source, and the light source light transmitted through the liquid crystal panel is formed into an image on the transmission screen by the image forming lens.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG.
FIG. 2 is a schematic sectional view of one of the two liquid crystal panels that transmits the red component LR, and FIG. 2 is a schematic configuration diagram of this projection type image display device.

The projection type image display apparatus according to the present embodiment has three liquid crystal panels 31R, 31R on which images to be projected are displayed.
G, 31B, a light source 10 that emits a light source light L, and the light source light L
Is decomposed into each component LR, LG, LB, and the liquid crystal panel 31R,
Liquid crystal panels 31R, 31G, 31 while guiding to 31G, 31B
An optical system that superimposes the respective components LR, LG, and LB that have passed through B, and the respective components L that have passed through the liquid crystal panels 31R, 31G, and 31B.
A projection lens 40 for enlarging and projecting R, LG, and LB on the screen 50, and an exit side transparent substrate 312R of the liquid crystal panels 31R, 31G, and 31B (only the liquid crystal panel 31R is shown in the drawing, but other The same), but three transmissive screens 60R, 60G, 60 that are installed at a predetermined distance
B and. Then, the liquid crystal panels 31R, 31G, 31
Each component LR, LG, and LB transmitted through B is a microlens
319R (only the liquid crystal panel 31R is shown in the drawing, but it is the same for other liquid crystal panels 31R) is configured to form an image on the transmissive screens 60R, 60G, and 60B.

The three liquid crystal panels 31R, 31G, and 31B display an image to be projected on the screen 50, which is decomposed into R, G, and B components. The R component LR of the light source light L is incident on the liquid crystal panel 31R on which the displayed image is displayed. In addition, each liquid crystal panel 31
Condenser lens 32 on the incident side of R, 31G, 31B
R, 32G and 32B are provided respectively.

Hereinafter, the liquid crystal panel 31R will be taken as an example in the detailed description of the liquid crystal panel. The liquid crystal panel 31R includes two transparent substrates, that is, an incident side transparent substrate 311R and an emission side transparent substrate 312R, a liquid crystal 313 enclosed between both transparent substrates 311R and 312R, and the outside of both transparent substrates 311R and 312R. Provided in 2
It has sheets of polarizing plates 314R and 315R. Incident side transparent substrate
A transparent common electrode 316R is provided on the 311R, and a pixel electrode 317R is provided on the emission side transparent substrate 312R.

Further, a black matrix 318R is provided on the incident side transparent substrate 311R. This black matrix 318R has openings 318r corresponding to the pixel electrodes 317R.
And a portion other than the opening 318r does not transmit light.

On the other hand, a pixel electrode is formed on the emission side transparent substrate 312R.
A microlens 319R is provided at a position corresponding to 317R. The microlens 319R forms an image of the component LR transmitted through the pixel electrode 317R on the transmission screen 60R. On the other hand, the transmissive screen 60R is made of an acrylic plate, a glass plate, or the like, and is at a predetermined distance from the exit side transparent substrate 312R of the liquid crystal panel 31R, that is, the microlens 31.
The components LR that have passed through 9R are placed apart by a distance such that they form an image without a gap.

As shown in FIG. 2, the optical system has four dichroic mirrors 21a, 21b, 21c and 21d and two total reflection mirrors 22a and 22b, each of which emits a light source light L. The components LR, LG, LB which are decomposed into the components LR, LG, LB and are transmitted through the respective liquid crystal panels 31R, 31G, 31B.
B is superimposed again.

The light source light L emitted from the light source 10 is UV-
The light passes through the IR filter 12 and is incident on the first dichroic mirror 21a. This first dichroic mirror
21a has a property of selectively reflecting only the component LR of the light source light L and transmitting the other components LG and LB. The component LR is incident on the liquid crystal panel 31R via the first total reflection mirror 22a.

The components LG and LB are incident on the second dichroic mirror 21b. The second dichroic mirror 21b selectively reflects the component LB, and the other component L
It has a property of transmitting G. The component LB is incident on the liquid crystal panel 31B, and the component LG is incident on the liquid crystal panel 31G.

The component LR incident on the liquid crystal panel 31R,
The component LB incident on the liquid crystal panel 31B is incident on the third dichroic mirror 21c. The third dichroic mirror 21c has a property of selectively reflecting the component LB and transmitting the component LR. Therefore, in the third dichroic mirror 21c, the component LR and the component LB are superimposed. The superimposed component LR and component LB are the fourth
It is guided to the dichroic mirror 21d.

On the other hand, the component LG is incident on the liquid crystal panel 31G. The component LG transmitted through this liquid crystal panel 31G is
4th dichroic mirror 21d with total reflection mirror 22b
Reflected in the direction.

The fourth dichroic mirror 21d to which the respective components LR, LG and LB transmitted through the respective liquid crystal panels 31R, 31G and 31B are guided, selectively reflects the component LG and transmits the other components LR and LB. It has the property. Therefore,
In the fourth dichroic mirror 21d, each component L
R, LG, and LB are superposed and are incident on the projection lens 40.

The projection lens 40 enlarges the respective components LR, LG, LB superposed on the fourth dichroic mirror 21d and enlarges and projects them on the screen 50.

Next, the operation of the projection type image display device having the above-mentioned structure will be described by taking the liquid crystal panel 31R as an example. Component LR of the light source light L incident on the liquid crystal panel 31R
Of the pixel electrode 317R transmits only the pixel electrode 317R in the open state according to the signal input to the liquid crystal panel 31R. The component LR transmitted through the pixel electrode 317R is incident on the microlens 319R and is projected onto the transmission screen 60R by the microlens 319R. Transparent screen 60
An image displayed on the liquid crystal panel 31R is formed on the R.

In this way, each liquid crystal panel 31R, 31G,
The light source light L transmitted through 31B is transmitted through each transmission screen.
Since the image is formed on 60R, 60G, and 60B, the black matrix portion, that is, the non-pixel portion is not projected on the screen 50. Therefore, even if the enlargement ratio is increased, the problem of image quality deterioration due to the black matrix does not occur.

[0021]

The projection type image display device according to the present invention includes a liquid crystal panel on which an image to be projected is displayed, a light source for emitting light source light, an optical system for guiding the light source light to the liquid crystal panel, and a liquid crystal panel. It has a projection lens for enlarging and projecting the transmitted light source light on a screen, and a transmission screen installed at a predetermined distance from the exit side transparent substrate of the liquid crystal panel,
An image forming lens corresponding to a pixel electrode is formed on the exit side transparent substrate of the liquid crystal panel, and the light source light transmitted through the liquid crystal panel is formed into an image on a transmission screen by the image forming lens. .. For this reason, the non-pixel portion corresponding to the black matrix is not projected on the transmissive screen, so that the image quality does not deteriorate due to this.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of one of three liquid crystal panels constituting this projection type image display apparatus that transmits a red component.

FIG. 2 is a schematic configuration diagram of this projection type image display device.

[Explanation of symbols]

 10 Light sources 21a to 21d Dichroic mirrors 31R, 31G, 31B Liquid crystal panel 311R Incident transparent substrate 312R Emitting side transparent substrate 317R Pixel electrode 318R Black matrix 40 Projection lens 50 Screen 60R, 60G, 60B Transparent screen 319R Imaging lens

Claims (1)

[Claims] 1. A liquid crystal panel on which an image to be projected is displayed, a light source for emitting a light source light, an optical system for guiding the light source light to the liquid crystal panel, and a projection for enlarging and projecting the light source light transmitted through the liquid crystal panel on a screen. The liquid crystal panel includes a lens and a transmissive screen installed at a predetermined distance from the exit side transparent substrate of the liquid crystal panel, and an imaging lens corresponding to a pixel electrode is formed on the exit side transparent substrate of the liquid crystal panel. The projection type image display device is characterized in that the light source light transmitted through the liquid crystal panel is focused on the transmissive screen by the imaging lens.