KR19990011537A - Lighting equipment for LCD projectors - Google Patents

Abstract

The present invention relates to a lighting device for a liquid crystal projector having a structure that can separate the incident light into R, G, B to directly focus to each pixel of the LCD panel in order to increase the light efficiency, the parallel incident light from the light source to one point A lens array unit comprising a plurality of micro lenses to focus, and a color separation laminated mirror for separating the white light focused by the lens array unit into R, G, B components and projecting to the LCD panel,

The color-divided stacked mirror unit is composed of a pair of color separation mirrors facing each other to form a predetermined angle, the first color separation mirror is a reflection surface is laminated in the order of R, G, B, the second color separation mirror is half The slope is characterized in that the stacking in the order of B, G, R.

Description

Lighting equipment for LCD projectors

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting apparatus for liquid crystal (LCD) projectors, and more particularly, to a lighting apparatus for liquid crystal projectors using an optical separation mirror to improve light efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the lighting apparatus for liquid crystal projectors generally used.

Referring to FIG. 1, reference numeral 110 denotes a light source emitting white light, 120 denotes a parabolic reflector reflecting white light emitted from the light source 110 and changing to parallel light, and 130 denotes the reflector 120 Denotes an LCD panel to which a color filter is attached so as to display an image using white parallel light reflected at

In the above configuration, the light emitted from the light source 110 is converted into parallel light by the reflector 120, contains color while passing through the color filter, and is projected with an image while passing through the LCD panel 130. In this case, the color filter includes an R, G, B filter for each pixel of the LCD panel 130, and transmits only a corresponding color, thereby displaying an image.

As a result, in the above configuration, since two-thirds of the white light is reflected or absorbed by the color filter due to the use of the color filter, the light efficiency is lowered, resulting in a decrease in the brightness of the projected image.

FIG. 2 is a diagram showing a part of the configuration of an illumination device for an LCD projector when a light beam having a wavelength required for displaying an image is incident on an LCD panel without using a color filter to solve the above problem.

Referring to FIG. 2, the B reflection mirror 211 reflects only the B component and transmits the R and G components from the white light supplied through the reflector 120 shown in FIG. 1, and the B reflection mirror 211. An R reflection mirror 212 reflecting only the R component and transmitting the G component among the transmitted R and G components, a G reflection mirror 213 reflecting the G component transmitted through the R reflection mirror 212, and B And an LCD panel 230 that condenses the output light of the reflection mirror 211, the R reflection mirror 212, and the G reflection mirror 213 and outputs them to a projection lens (not shown). At this time, the B reflection mirror 211, the R reflection mirror 212 and the G reflection mirror 213 is used as a plate overlap each other, the B reflection mirror 211 is disposed at an angle of 41 ° with respect to the horizontal plane, The R reflection mirror 212 is disposed at an angle of 45 ° with respect to the horizontal plane, and the G reflection mirror 213 is disposed at an angle of 49 ° with respect to the horizontal plane.

In addition, in front of the LCD panel 230, as shown in FIG. 3, the output beams of the B reflecting mirror 211, the R reflecting mirror 212, and the G reflecting mirror 213 are focused on each of the LCD panel 230. The microlens array 220 which emits light to the pixels is positioned.

In the case of the above-described configuration, in order for the R component reflected from the R reflection mirror 212 to be incident on the LCD panel 230, the B reflection mirror 211 must be transmitted again, and the G reflection mirror 213 In order to be incident on the LCD panel 230, the G component reflected from the C) must be transmitted again through the B reflection mirror 211 and the R reflection mirror 212. There is a problem that a color shift occurs.

In addition, since the spectroscopic and focusing is performed by each of the reflecting mirrors and the microlens array 220, the light propagation angle range is increased so that the light loss is increased, and the F no. There is a problem to be configured small.

The present invention has been made to solve the above problems, the object of the liquid crystal projector having a structure capable of direct focusing to each pixel of the LCD panel after separating the incident light into R, G, B in order to increase the light efficiency To provide a lighting device.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing the configuration of a lighting apparatus for a single-panel LCD projector when using an LCD panel with a general color filter;

2 is a view schematically showing a part of a configuration of a lighting device for an LCD projector when using an LCD panel with a microlens array;

3 is a view showing the action of the microlens applied to FIG.

4 is a view showing a part of the configuration of the first embodiment of the illumination device for an LCD projector according to the present invention;

5 is a view showing a color separation laminated mirror used in the present invention.

Explanation of symbols for main parts of the drawings

10 lens array unit 20 color separation mirror portion

21: first color separation mirror 26: second color separation mirror

30: LCD panel

According to a first aspect of the present invention for achieving the above object, the lens array unit consisting of a plurality of microlenses for focusing parallel incident light from the light source to a point, and the white light focused by the lens array unit R And a color separation lamination mirror projecting the LCD panel by separating the G and B components, wherein the color separation lamination mirror comprises a pair of color separation mirrors facing each other to form a predetermined angle, and the first color separation mirror is The reflective surfaces are stacked in the order of R, G, and B, and the second color separation mirror has the reflective surfaces stacked in the order of B, G, and R.

According to a second aspect of the present invention, the color separation mirror uses a different thickness of the laminated plate shape of each reflective surface.

Hereinafter, with reference to the accompanying drawings a preferred embodiment of a lighting device for a liquid crystal projector according to the present invention will be described in detail.

4 is a view showing a part of the configuration of the lighting apparatus for a liquid crystal projector according to the present invention, Figure 5 is a view showing a color separation laminated mirror used in the present invention.

Referring to FIG. 4, a lens array unit 10 including a plurality of microlenses focusing parallel incident light from a light source (not shown) into a single point and white light focused by the lens array unit 10 may be R, It includes a color separation laminated mirror 20 to be separated into the G, B components and projected to the LCD panel 30.

The color separation mirror 20 is composed of a pair of color separation mirrors 21 and 26 facing each other to form a predetermined angle as shown in (A) of FIG. 5, and the first color separation mirror 21. ), The reflective surfaces are stacked in the order of R, G, B, and the second color separation mirror 26 is the reflective surfaces are stacked in the order of B, G, R. In this case, as shown in FIG. 5B, the color separation mirrors 21 and 26 focus light on the same plane where the LCD panel is located when the focusing position of each color is different due to chromatic aberration of the microlenses. The thickness of the laminated board shape which each reflection surface has can be used.

In the above configuration, the color separation laminated mirror 20 serves to match the focus focus position while adjusting the focusing position spacing of each color of R, G, and B. For example, as shown in FIG. 4, the pixel size of the LCD panel 30 is Is the thickness of each laminate That is, when the light travel distance is a, the distance between R, G, and B light incident and separated by each microlens is approximately 2a.

Looking at the operation of the present invention having the configuration as described above are as follows.

When white parallel light is incident on the lens array unit 10 from a light source unit (not shown) consisting of a light source and a reflector, the incident parallel light proceeds to focus on a plurality of separate points by the action of each micro lens. In this case, the traveling light is separated into three lights having a distance interval of 2a for each of R, G, and B by the first and second color separation mirrors 21 and 26 of the color separation laminated mirror 20, and the LCD panel. Focusing is done at the position of 30.

After all, the present invention is applied to a single-panel LCD projector by separating the incident light by R, G, B so as to focus on each pixel of the LCD panel.

As described above, the illumination device for a liquid crystal projector according to the present invention separates incident light for each of R, G, and B to directly focus the pixels of the LCD panel. There is an effect that can solve the problems such as loss caused by the difference, and the degree of freedom in the system configuration.

In addition, since the angles of R, G, and B incident on the LCD panel are the same, the F no. (Lens diameter / focal length) of the projection lens can be increased, and color shift can be prevented. It works.

Claims (2)

A lens array unit consisting of a plurality of microlenses for focusing parallel incident light from a light source into one point, and a color-separated stacked mirror for separating the white light focused by the lens array unit into R, G, and B components and projecting them onto an LCD panel. In the illuminating device for a liquid crystal projector containing a part, The color-divided stacked mirror unit is composed of a pair of color separation mirrors facing each other to form a predetermined angle, the first color separation mirror is a reflection surface is laminated in the order of R, G, B, the second color separation mirror is half Illumination device for a liquid crystal projector, characterized in that the four sides are stacked in the order of B, G, R. The method of claim 1, The color separation mirror in which the reflecting surfaces reflecting the components of R, G, and B are stacked is different in the thickness of the laminated plate shape of each reflecting surface.