JP2005107400A - Color wheel, filter device and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dynamically vary the hue even during a projection, for example, to easily switch a projection of luminosity priority and a projection of color reproducibility priority without giving an uncomfortable feeling to an observer. <P>SOLUTION: The color wheel 21 has a red transmissive part 21r which transmits R (red) light, a green transmissive part 21g which transmits G (green) light, a blue transmissive part 21b which transmits B (blue) light and a white transmissive part 21w which transmits W (white) light as it is, the ratio at which the respective transmissive parts occupy vary according to the distance from the center of rotation. The ratio at which the white transmissive part 21w occupies is zero near the center of rotation. Further, a mechanism which moves the center of rotation of the color wheel is provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a color wheel, a filter device, and a projector, and in particular, filters that transmit R (red), G (green), and B (blue) light, respectively, in order to separate incident white light in a time-division manner. Further, the present invention relates to a color wheel arranged in the circumferential direction, a filter device having the color wheel, and a projector for projecting an image having the color wheel.

  In recent years, a single-plate DLP (Digital Light Processing (registered trademark)) projector has been used as a projector for enlarging and projecting an input image on a screen or a wall.

  FIG. 6 is a diagram showing an example of a color wheel used in a conventional single plate DLP projector. A conventional color wheel 521 includes a red transmission part 521r that transmits R (red) light, a green transmission part 521g that transmits G (green) light, a blue transmission part 521b that transmits B (blue) light, and W The white transmission part 121w which permeate | transmits the light of (white light) as it is is provided. FIG. 7 is a diagram showing the relationship between the distance from the center of the color wheel and the angle of each filter. As can be seen from FIGS. 6 and 7, in the conventional color wheel 521, the ratios of R, G, B, and W are constant regardless of the distance from the center. That is, the boundary between the colors is a straight line extending radially from the center of the color wheel 521.

  In addition, a color wheel including two colorings having different color ratios is disclosed (for example, see Patent Document 1).

JP 2003-167297 A

  Since the conventional color wheel described above has a fixed color ratio, there is a problem in that the hue of the image projected on the screen cannot be changed.

  In the color wheel disclosed in Patent Document 1, the hue of the image projected on the screen can be changed. However, if the hue is changed during the projection, the hue changes discontinuously, so that the viewer can see There is a problem of giving a sense of incongruity.

  An object of the present invention is to provide a color wheel that can be easily changed without giving a sense of incongruity to a person who changes the hue dynamically even during projection, for example, switching between emphasizing luminance and emphasizing color reproducibility. Another object of the present invention is to provide a filter device having a wheel and a projector for projecting an image having the color wheel.

  The color wheel of the present invention is a color wheel having a red transmissive part, a green transmissive part, a blue transmissive part, and a white transmissive part, and the proportion of each transmissive part varies depending on the distance from the rotation center. And

  The color wheel of the present invention is a color wheel having a red transmission part, a green transmission part, a blue transmission part, and a white transmission part, and the proportion of each transmission part changes continuously according to the distance from the rotation center. This may be a feature.

  The color wheel of the present invention may be characterized in that the ratio of the white transmission portion is 0 near the rotation center.

  The color wheel of the present invention may be characterized in that the ratio of the white transmission portion is 0 near the outer periphery.

  The color wheel of the present invention may be characterized in that the ratio of the red transmission part, the green transmission part, and the blue transmission part is constant regardless of the distance from the rotation center.

  The filter device of the present invention includes the color wheel according to any one of claims 1 to 5 and a moving mechanism that moves the color wheel, and the moving mechanism has an optical path that is incident on the color wheel as the color wheel. The rotation center point of the color wheel is moved so as to change from near the center of the wheel to near the outer periphery.

  The filter device of the present invention may include a brightness detection unit that detects the brightness of the projected image, and may operate the moving mechanism based on a detection result of the brightness detection unit.

  The filter device of the present invention may include an input signal determination unit that determines an image input signal and operate the moving mechanism based on a determination result of the input signal determination unit.

  The projector of the present invention includes a filter device according to any one of claims 6 to 8, a light source that emits white light, a mirror that reflects light emitted from the light source and transmitted through the filter device, And a projection lens for projecting the light reflected by the mirror.

  According to the present invention, since the color wheel in which the ratio of the red transmission part, the green transmission part, the blue transmission part, and the white transmission part changes with the distance from the rotation center point is moved with respect to the optical path, emphasis on luminance and color reproducibility There is an effect that an important continuous switching can be easily performed.

  The best mode for carrying out the present invention will be described in detail with reference to the drawings. FIG. 3 is a block diagram showing the configuration of the embodiment of the present invention.

  The projector 1 projects an image on the screen 2 or a wall. The projector 1 includes a lamp 10, a filter device 20, a mirror 30, a projection lens 40, and a projector control unit 50 that controls these units.

  The lamp 10 is a light source that emits white light. The filter device 20 is placed on the optical path emitted from the lamp 10. The mirror 30 reflects the emitted light that has passed through the filter device 20. For example, DMD (Digital Micromirror Device, registered trademark) is used as the mirror 30. The DMD includes hundreds of thousands of micromirrors each capable of controlling the tilt angle. Each micromirror corresponds to each pixel of the image displayed on the screen 2, and an arbitrary image can be displayed by controlling the inclination angle of each micromirror. Specifically, for a certain micromirror, angle control is performed so that the reflected light deviates from the screen 2, and for a certain micromirror, the reflected light is guided to a corresponding pixel position on the screen 2. A desired image is obtained by performing angle control. The projection lens 40 enlarges and projects the light reflected by the mirror 30 onto the screen 2.

  FIG. 1 is a diagram showing the configuration of the color wheel 21. The color wheel 21 includes a red transmission part 21r that transmits R (red) light, a green transmission part 21g that transmits G (green) light, a blue transmission part 21b that transmits B (blue) light, and a W (white). A white transmitting portion 21w that transmits the light as it is. FIG. 2 is a diagram illustrating the relationship between the distance from the center and the angle of each filter. As can be seen from FIG. 1 and FIG. 2, as the distance from the center of the color wheel 21 increases, the proportion of the area of the white transmission part 21w increases, and high luminance display can be performed. This is suitable for use in presentations. In addition, the portion close to the center is free of the white transmitting portion 21w, so that the color purity is high and suitable for movie viewing. On the contrary, the ratio of the area of the white transmission part 21w near the outer periphery of the color wheel 21 may be zero.

  FIG. 4 is a block diagram showing the configuration and operation of the filter device 20. The filter device 20 includes a color wheel 21, a wheel motor 22, a wheel support part 23, a feed mechanism 24, a feed motor 25, and a filter control part 26 that controls these parts.

  The wheel motor 22 drives the color wheel 21 to rotate. The wheel support portion 23 supports the color wheel 21. The feed mechanism 24 is driven by a feed motor 25, and moves the wheel support portion 23 and the color wheel 21 in the left-right direction in FIG. The mechanism for moving the color wheel 21 can be realized by, for example, providing a rack gear on the wheel support portion 23, providing a worm gear on the feed mechanism 24, and rotating the feed motor 25.

  FIG. 4A shows a state in which the color wheel 21 is moved leftward, and the optical path 11 is at a position close to the center of the color wheel 21. FIG. 4B shows a state in which the color wheel 21 is moved rightward, and the optical path 11 is at a position far from the center of the color wheel 21 and in the vicinity of the outer peripheral portion. By this moving mechanism, it is possible to continuously change from a state in which many white transmission parts 21w are used to a state in which no white transmission parts are used.

  With this mechanism, the optical path 11 toward the DMD can be freely used from the outside to the inside of the color wheel 21, and the luminance priority and the color purity priority can be varied.

  In addition, when the currently displayed image is dark, priority is given to color purity, and when it is bright, priority is given to luminance. For example, improvement in contrast can be expected by changing according to the image.

  FIG. 5 is a block diagram illustrating an example of the filter control unit 26. The filter control unit 26 includes a brightness detection unit 261, a brightness correspondence table 262, an input signal determination unit 263, an input signal correspondence table 264, and a feed motor drive unit 265.

  The brightness detection unit 261 detects the brightness of an image to be projected and displayed. The brightness correspondence table 262 is a table that associates the brightness detected by the brightness detection unit 261 with the optimum position of the optical path 11 on the color wheel 21. The feed motor drive unit 265 drives the feed motor 25 so that the light path 11 on the color wheel 21 is at the optimum position with reference to the brightness correspondence table 262 based on the detection result of the brightness detection unit 261.

  Thereby, according to the brightness of the image to be projected and displayed, color purity priority and luminance priority can be dynamically switched in real time. Since switching can be performed continuously, it is possible to prevent the color of the video from changing discontinuously. For this reason, it does not give an uncomfortable feeling to the person who is watching the video.

  The input signal determination unit 263 determines the type of the input signal to the projector 1. The input signal correspondence table 264 is a table associating the types of input signals detected by the input signal determination unit 263 with the optimum positions of the optical path 11 on the color wheel 21. The feed motor driving unit 265 drives the feed motor 25 so that the optical path 11 on the color wheel 21 is at the optimum position with reference to the input signal correspondence table 264 based on the determination result of the input signal determination unit 263.

  The input signal determination unit 263 is set so as to determine, for example, whether the input signal is an RGB input signal or a video input signal. In this case, priority is given to luminance if the input signal is an RGB input signal, and priority is given to color purity if the input signal is a video input signal.

  Further, the input signal determination unit 263 may determine the file name of the input file or the extension included in the file name to determine whether it is presentation data or movie data.

  The switching between the luminance priority and the color purity priority may be performed by the operator from the operation panel. Furthermore, the operator operation and the automatic control of the filter control unit 26 may be selectable.

It is a figure which shows the structure of a color wheel. It is a figure which shows the relationship between the distance from a center, and an angle of each filter in a color wheel. It is a block diagram which shows the structure of embodiment of this invention. It is a block diagram which shows the structure of a filter apparatus. It is a block diagram which shows an example of a filter control part. It is a figure which shows the example of the color wheel used with the conventional single plate DLP projector. It is a figure which shows the relationship between the distance from a center, and an angle of each filter in the conventional color wheel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projector 2 Screen 10 Lamp 11 Optical path 20 Filter apparatus 21 Color wheel 21r Red transmission part 21g Green transmission part 21b Blue transmission part 21w White transmission part 22 Wheel motor 23 Wheel support part 24 Feed mechanism 25 Feed motor 30 Mirror 40 Projection lens 50 Projector Control unit 261 Brightness detection unit 262 Brightness correspondence table 263 Input signal determination unit 264 Input signal correspondence table 265 Feed motor drive unit

Claims (9)

A color wheel having a red transmissive part, a green transmissive part, a blue transmissive part, and a white transmissive part, wherein the proportion of each transmissive part varies depending on the distance from the center of rotation. A color wheel having a red transmissive part, a green transmissive part, a blue transmissive part, and a white transmissive part, wherein the proportion of each transmissive part continuously changes according to the distance from the rotation center. . 3. The color wheel according to claim 1, wherein a ratio of the white transmission portion is 0 near the rotation center. 3. The color wheel according to claim 1, wherein the ratio of the white transmission part is 0 near the outer periphery. The color wheel according to claim 1, 2, 3, or 4, wherein the ratio of the red transmission part, the green transmission part, and the blue transmission part is constant regardless of the distance from the rotation center. 6. A color wheel according to claim 1, and a moving mechanism for moving the color wheel, wherein the moving mechanism has an optical path incident on the color wheel near the outer periphery from the center of the color wheel. The filter device is characterized in that the rotation center point of the color wheel is moved so as to change up to. The filter device according to claim 6, further comprising a brightness detection unit that detects brightness of a projected image, and operating the moving mechanism based on a detection result of the brightness detection unit. 8. The filter device according to claim 6, further comprising an input signal determining unit that determines an image input signal, and operating the moving mechanism based on a determination result of the input signal determining unit. The filter device according to any one of claims 6 to 8, a light source that emits white light, a mirror that reflects light emitted from the light source and transmitted through the filter device, and light reflected by the mirror A projector having a projection lens for projecting.

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