JPH1130712A - Color wheel for video projection equipment - Google Patents

Abstract

(57) Abstract: A color wheel rotatably provided on an optical path for realizing a color image of a video projection device such as a projection television. A color wheel is attached to a funnel-shaped body part which is sequentially extended from a cylindrical support part to receive a driving motor so as to be evenly distributed with color filters to make the image more compact. The space utilization in the optical arrangement of the projection device is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color wheel provided in a color image projection apparatus, which is provided on a light path for realizing a color image.

[0002]

2. Description of the Related Art An image projection apparatus such as a projection television or a video projector is, for example, a liquid crystal display element.
An image is formed by an image display means such as a liquid crystal display (LCD) or a small cathode ray tube (CRT), and the formed image is enlarged by an optical lens mechanism and projected on a large screen.

Referring to FIG. 1 showing an optical arrangement of a conventional reflection type projector apparatus as such an image projection apparatus, a light source 10 includes a lamp 11 for emitting white light, such as a metal halide lamp, and And a reflecting mirror 12 for reflecting light emitted from the lamp 11 to one side. The reflected light passes through a color wheel 20 provided with red (R), green (G), and blue (B) color filters, and then passes through a scrambler 31 for making incident light uniform.

Then, the light is converged by a converging lens 32 and a collimating lens 33, and becomes parallel light.
Polarizing beam splitter 40 for changing the traveling path of incident light
Is incident on. Reference numeral 50 denotes a reflective liquid crystal display element that selectively reflects incident light to form an image,
Is a projection lens unit for projecting an image on a screen (not shown).

In the above configuration, the color wheel 20
Has a drive motor 21 and a disk 23 connected to an output shaft 22 and rotated as shown in FIG. The disk 23 is composed of R, G, and B color filters 24 having the same area. In FIG. 2, the color filter 24 is divided into six equal parts, but can be equally divided by a multiple of three depending on the driving characteristics of the image projection device.

The disk 23 is rotated so that any one of R, G, and B color filters is positioned on an optical path in accordance with the response speed of the reflection type liquid crystal display element 50, thereby providing the light source. Light of a specific color is selectively transmitted from the light irradiated from step 10. However, since the color wheel 20 uses a disk, there is a problem that the optical structure of the image projection device occupies a lot of space.

[0007]

A technical problem to be solved by the present invention is to improve the above-mentioned problems of the conventional color wheel, and an object of the present invention is to provide an image projection apparatus. Another object of the present invention is to provide a more compact color wheel so as to improve the space utilization in the optical arrangement of the present invention.

[0008]

In order to achieve the above object, a color wheel of an image projection apparatus according to the present invention has a support rotated by a driving source, and transmits light emitted from a light source at a specific wavelength. As a result, a color filter selectively positioned on the optical path is attached by rotation,
A funnel-shaped body portion sequentially extended from the support portion.

Further, the color wheel is provided so as to be inclined such that its rotation axis forms a predetermined angle with the optical axis of the light.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 3, a color wheel of an image projection device according to an embodiment of the present invention has R, G, B colors.
Wheel member 210 consisting of color filters 213
And a drive motor 220 for rotating the wheel member 210
And The wheel member 210 is connected to the drive motor 220
And a body part 211 to which the color filter 213 is attached.

According to the present invention, the body 211 has a funnel shape that is extended from the support 212 sequentially. The supporting part 212 receives the driving motor 220 and is connected to an output shaft 221 of the supporting part 212, and is preferably made of a metal material. The body 211 is made of glass or transparent acrylic, and a color filter 213 is attached thereto.

Although the color filter 213 is divided into six equal parts in FIG. 3, it may be divided into three equal parts or multiples of three depending on the driving characteristics of the image projection apparatus. FIG. 4 is a view showing an optical arrangement of an image projection apparatus to which the color wheel according to the present invention is applied, and the same reference numerals as those in the above-described figures denote the same components.

Referring to FIG. 4, the color wheel according to the present invention is provided on the optical path so that its rotation axis "S" is at a fixed angle to the optical axis L of the light emitted from the light source 10. Can be As described above, the body 211 has R, G,
A color filter 213 of B color is attached so as to be evenly distributed, but the drive motor 220 has one of R, G, and B filters according to the response speed of the reflective liquid crystal display element 50. The body 211 is rotated so as to be selectively located on the optical path.

Accordingly, the light reflected from the reflecting mirror 12 becomes uniform while passing through one of the color filters 213 and then through the scrambler 31 depending on the wavelength.
Next, the light is focused by a focusing lens 32 and a collimating lens.
After being converged by the respective 33 and becoming parallel light, they pass through the polarizing beam splitter 40 and enter the reflective liquid crystal display element 50.

Next, the light reflected by the image formed on the reflection type liquid crystal display element 50 is reflected by the polarization beam splitter 40.
Then, the traveling path is changed and enlarged by the projection lens unit 60, and finally projected onto a screen (not shown).

[0016]

The color wheel of the image projection apparatus according to the present invention can be relatively reduced in volume by adopting a funnel-shaped body portion instead of the conventional disk type, so that the optical arrangement of the image projection apparatus can be reduced. Space utilization can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an optical arrangement of a conventional reflection type liquid crystal projector device.

FIG. 2 is a schematic perspective view showing a color wheel in the projector device of FIG.

FIG. 3 is a schematic perspective view showing a color wheel for an image projection device according to the present invention.

FIG. 4 is a diagram showing a configuration of a reflection type liquid crystal projector device employing the color wheel of FIG. 3;

[Explanation of symbols]

 210 Wheel member 211 Body 212 Support 213 Color filter 220 Drive motor 221 Output shaft

Claims (4)

[Claims] 1. A supporting part rotated by a driving source, and a color filter selectively positioned on an optical path by rotation so as to transmit light emitted from a light source at a specific wavelength, are attached to the supporting part. A funnel-shaped body portion that is sequentially extended. 2. The color wheel according to claim 1, wherein the body is made of one of glass and transparent acryl. 3. The color wheel according to claim 1, wherein the support is made of a metal material. 4. The color wheel according to claim 1, wherein the color wheel is provided so that a rotation axis thereof is inclined with respect to an optical axis of the light.