JP2009271145A - Wide-angle projection type video display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wide-angle projection type video display apparatus for eliminating color irregularity caused by reflection from a main body case on a projection surface. <P>SOLUTION: The wide-angle projection type video display apparatus such as a three-plate type wide-angle liquid crystal projector 1 includes: a main body case 1a whose surface is formed in color set in advance, a projection lens using a short focus lens, and an aspherical reflection mirror reflecting video light from the projection lens toward the projection surface. The three-plate type wide angle liquid crystal projector 1 includes a color irregularity correction part 15 uniformizing an irregular color area due to reflected light from the main body case 1a on the projection surface. Thus, apparent color uniformity is held, and a video image having no sense of incongruity is displayed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a wide-angle projection type equipped with a short-focus projection lens that projects video generated by a computer or the like and video signal data recorded on a recording medium such as an optical disk or a magnetic tape onto a projection surface such as a screen as video light. The present invention relates to a video display device.

Projection-type video display devices are used as video display devices in various facilities such as home theaters, conference rooms, training rooms, classrooms, amusement halls, various exhibition rooms, and studios. Conventionally, a liquid crystal projector as a normal projection type image display device often requires a projection distance of several meters between the liquid crystal projector and a projection surface such as a screen or a wall, and puts an object that blocks light between them. Since it was not possible, there was a problem that the usage environment was restricted. Therefore, in order to eliminate such inconvenience, a short-focus wide-angle projection image display device has been developed that is flexible and has improved installation by shortening the projection distance between the projector body and the projection surface. ing. Such a wide-angle projection display apparatus is a three-plate wide-angle liquid crystal projector described in Patent Document 1, for example. This three-plate type wide-angle liquid crystal projector uses a short focus lens as a projection lens, reflects image light from the projection lens by an aspherical reflection mirror, and projects it onto a projection surface such as a screen or a wall. The projection surface is formed so as to be capable of wide-angle projection only by placing a slight distance between the surface and the apparatus.
JP 2004-252049 A

  However, when such a three-plate wide-angle liquid crystal projector is installed, since the distance from the main body case to the projection surface is short, the reflected light from the main body case is irradiated to the projection surface, and there is an uneven color region that gives an unnatural appearance. It was found that there was a problem that it was formed on the projection surface. This will be described with reference to FIG. FIG. 4 shows an installation example in which such a three-plate type wide-angle liquid crystal projector 1 is installed on the mounting table 2 and projected onto the wall surface 3. FIG. 4A is a side view showing a state in which the image light 5 emitted from the projection lens 4 is reflected by the aspherical reflection mirror 6 and projected onto the wall surface 3. FIG. 5B shows the projection plane 7 as viewed from the front. As shown in FIG. 4B, since the main body case 1a is close to the projection surface 7, the reflected light from the main body case 1a is irradiated to the lower part of the projection surface 7, and the color unevenness that gives the appearance color uncomfortable. It was found that region 8 was formed. Such an uneven color region 8 on the projection surface 7 is caused by the same phenomenon even when the three-plate wide-angle liquid crystal projector 1 is installed on the floor surface and projected onto the floor surface.

  It should be noted that the size, position, discomfort, and discomfort of the color unevenness area 8 generated in this way also affect the surface quality of the projection surface and the brightness of the space where the wide-angle projection display device is installed. However, the shape mainly affects the color of the surface of the main body case, the distance from the main body case to the projection surface, the shape of the main body case, particularly the reflection angle to the projection surface.

  The present invention has been made under such a background, and an object of the present invention is to provide a wide-angle projection display apparatus that eliminates color unevenness based on reflected light from a main body case on a projection surface.

  A wide-angle projection display apparatus according to the present invention includes a main body case having a surface formed with a predetermined color, a light modulation element, a projection lens using a short focus lens, and directs image light from the projection lens to a projection surface. A wide-angle projection display device including an aspheric reflection mirror that reflects light and includes a color unevenness correction unit that uniformizes a color unevenness region due to reflected light from a main body case on a projection surface. To do. If comprised in this way, since the color nonuniformity by the reflected light from the main body case in a projection surface is eliminated, a video without a sense of incongruity can be displayed.

  In addition, when the wide-angle projection display apparatus is installed, the color unevenness correction unit is configured so that the position of the color unevenness region on the projection plane is input by inputting the distance from the main body case to the projection plane using a user menu. It may be configured such that the calculated uneven color region on the projection plane is corrected. Since the position of the uneven color region is determined by the distance from the main body case to the projection surface, it is possible to grasp the relationship between the distance from the main body case to the projection surface and the position of the uneven color region in advance. Therefore, when the user inputs the distance from the main body case to the projection surface, the color unevenness on the projection surface can be automatically corrected without specifically specifying the position of the color unevenness region.

  Further, the color unevenness correction unit calculates a correction coefficient based on at least the color of the surface of the main body case, the reflection angle from the main body case, and the distance from the main body case to the projection surface, and based on the correction coefficient, the light modulation element It is preferable that the RGB video signals before being applied are corrected so as to be corrected. With this configuration, by storing information necessary for color unevenness correction in advance, color unevenness is automatically processed based on this information, so that the user's labor can be simplified.

  Further, it is preferable that the color unevenness correction unit is configured so that a correction coefficient can be adjusted by a user menu. With this configuration, it is possible to correct the influence on color unevenness due to the quality of the projection surface, the brightness of the space in which the wide-angle projection display device is installed, etc. based on the user's feeling, and the user satisfaction Can be improved.

  In addition, the color unevenness correction unit is preferably formed so that the distance from the main body case to the projection plane can be set steplessly within a predetermined range in the user menu. If comprised in this way, when the setting distance to a main body case and a projection surface is changed and attached, color unevenness correction | amendment can be performed easily.

  According to the present invention, the color unevenness correction unit that uniformizes the color unevenness region due to the light reflected from the main body case on the projection surface is provided. It is possible to display video without

(Embodiment 1)
A wide-angle projection display apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. The wide-angle projection display apparatus according to the present embodiment is a three-plate type wide-angle liquid crystal projector 1 using a liquid crystal panel as a light modulation element, and FIG. 1 is a block diagram showing the configuration of its control drive circuit. In the following description, components common to the general three-plate wide-angle liquid crystal projector 1 shown in FIG. 4 will be described using the same reference numerals.

In the three-plate wide-angle liquid crystal projector 1 according to the present embodiment, the main body case 1a is formed in a predetermined color. The color of the surface may be either the paint color or the color of the material itself.
The three-plate wide-angle liquid crystal projector 1 has a control drive circuit shown in FIG. As shown in this figure, various video playback devices such as an analog PC, a digital PC, a video, and a television are connected to an input signal processing unit 11 via an input terminal. The input signal processing unit 11 includes an input interface such as an analog I / F, a digital I / F, and a video I / F so as to be compatible with various video signals input from an input terminal. The video signal input to the input signal processing unit 11 is subjected to appropriate processing such as A / D conversion and decoding corresponding to the input video signal, and is output to the video signal processing unit 12 as a digital RGB video signal. .

  The video signal processing unit 12 uses the frame memory 13 and the like, is subjected to scaling processing into a signal format appropriate for the panel size, and is output to the video signal correction unit 14. The video signal correction unit 14 performs gamma correction on the scaled video signal and performs luminance correction to prevent the occurrence of a reverse tilt domain. In the digital RGB video signal output from the video signal correction unit 14, the color unevenness correction unit 15 corrects the aforementioned color unevenness based on a certain algorithm. Further, the digital RGB video signal corrected for color unevenness is converted into a signal form that can drive the R liquid crystal panel 17, the G liquid crystal panel 18, and the B liquid crystal panel 19 in the liquid crystal panel drive unit 16, and the R liquid crystal panel. 17, drive pulses for driving the G liquid crystal panel 18 and the B liquid crystal panel 19 are simultaneously generated. These are input to the R liquid crystal panel 17, the G liquid crystal panel 18, and the B liquid crystal panel 19.

  The R liquid crystal panel 17, the G liquid crystal panel 18, and the B liquid crystal panel 19 have rotation angles corresponding to the input video signals, respectively, and generate video light by transmitting light from the light source lamp 20. Further, the image light 5 generated in this way is emitted from the projection lens 4 and reflected by the aspheric reflection mirror 6 and is given from the aspheric reflection mirror 6 in the same manner as the conventional one shown in FIG. The image is formed on a wall surface 3 or the like located at a distance.

  The control CPU 21 accommodated in the control drive circuit includes the video signal processing unit 12, the input signal processing unit 11, the video signal correction unit 14, the color unevenness correction unit 15, the liquid crystal panel drive unit 16, the power supply circuit 22, and the light source. The overall control of the lamp control circuit 23 that controls the lamp 20, various sensors 24 that detect the temperature and inclination angle of each part, and the abnormality detection sensor 25 that detects abnormality of each part is controlled.

Next, details of the color unevenness correction unit 15 and an algorithm for color unevenness correction will be described.
FIG. 2 is an internal block diagram of the color unevenness correction unit 15. The horizontal synchronization signal and the vertical synchronization signal input to the color unevenness correction unit 15 are input to the address counter circuit 31. The address counter circuit 31 generates and designates a horizontal address indicating a pixel position in the horizontal direction and a vertical address indicating a pixel position in the vertical direction, which are unit elements constituting the image of the uneven color region 8. The horizontal address and the vertical address include data such as the color of the surface of the main body case 1a unique to the three-plate type wide-angle liquid crystal projector 1, and the distance between the projection surface in the installed state and the main body case 1a of the three-plate type wide-angle liquid crystal projector 1. By inputting from the user menu, the calculation is performed in consideration of the reflection angle from the main body case 1 a and is given to the address counter circuit 31. The color unevenness correction unit 15 includes a horizontal RUT 32 that stores a horizontal correction coefficient Kh and a vertical RUT 33 that stores a vertical correction coefficient Kv for each digital RGB video signal. Further, the horizontal RUT 32 and the vertical RUT 33 are configured to be preset from the control CPU 21 by inputting the distance between the projection surface 7 and the main body case 1a through the user menu.

The counter signal generated by the address counter circuit 31 is input to each RUT as a read address for the horizontal RUT 32 and the vertical RUT 33. Thereby, the horizontal correction coefficient Kh and the vertical correction coefficient Kv corresponding to the position of each pixel in the projection plane 7 are read out. The horizontal correction coefficient Kh and the vertical correction coefficient Kv are individually set for each RGB video signal. Then, the horizontal correction coefficient Kh and the vertical correction coefficient Kv read for each digital RGB video signal of each pixel are input to the coefficient calculation circuit 34, and the correction coefficient K is calculated according to the following equation (1). Then, the calculated correction coefficient K is output to the signal calculation circuit 35.
K = (Kh + Kv) / 2 (Formula 1)
Further, in the signal calculation circuit 35, the input video input signal SI is corrected by the following equation 2, and the corrected video signal is output to the subsequent liquid crystal panel driving unit 16 as the video output signal SO.
SO = SI × K (Formula 2)
Here, based on FIG. 3, an example of the horizontal correction coefficient Kh and the vertical correction coefficient Kv set for the horizontal RUT 32 and the vertical RUT 33 in the present embodiment will be described. FIG. 3 is an explanatory diagram of the horizontal RUT and the vertical RUT. The correction coefficient Kh stored in the horizontal RUT 32 above the projection surface 7 on which the color unevenness 8 is formed, and the left side of the projection surface 7. The correction coefficient Kv stored in the vertical RUT 33 is shown respectively.

  3 shows that, for example, for one of the RGB video signals, the vertical correction coefficient Kv stored in the vertical RUT 33 is 1 outside the uneven color region 8 at the top of the projection plane 7, and the projection plane 7 is set to be 0.85 in the uneven color region 8 below. Similarly, the horizontal correction coefficient Kh is set to 0.9 at the center of the projection surface 7 (inside the uneven color region 8) and to 1 at both ends of the projection surface 7 (outside the uneven color region 8). It shall be.

In this case, the correction coefficient K for the one video signal in the pixel at the upper left end of the screen, that is, the pixel outside the uneven color region 8 is expressed by the following equation (1).
K = (Kh + Kv) / 2 = (1 × 1) / 2 = 1
The output signal SO is given by Equation 2
SO = SI × K = SI × 1 = SI
It becomes. This means that the one video input signal SI is output without being corrected.

Further, the correction coefficient K for the one video signal in the lowermost pixel in the center of the screen, that is, the pixel in the color unevenness region 8 is expressed by the following equation (1).
K = (Kh + Kv) / 2 = (0.9 × 10.85) /2=0.875
And the output signal SO is given by
SO = SI × K = SI × 0.875 = 0.875 × SI
It becomes. This means that the one video input signal SI is output by being multiplied by 0.875.

  In this way, the correction coefficient K is calculated for each of the RGB video signals in all the pixels, and the video input signal SI is corrected, whereby the apparent appearance on the projection surface 7 projected on the screen in the uneven color region 8. Color uniformity is maintained.

Since the embodiment according to the present invention is configured as described above, the following operational effects can be obtained.
(1) Since the three-plate type wide-angle liquid crystal projector 1 as the wide-angle projection display apparatus according to the present embodiment includes the color unevenness correction unit 15, the color unevenness on the projection surface 7 due to the reflected light from the main body case 1a. Can be eliminated, and an uncomfortable video can be displayed.

  (2) When the three-plate wide-angle liquid crystal projector 1 is installed, the color unevenness correction unit 15 receives the distance from the main body case 1a of the three-plate wide-angle liquid crystal projector 1 to the projection plane 7 by the user menu. The position of the uneven color region 8 on the projection surface 7 is calculated, and the calculated uneven color region 8 on the projection surface 7 is corrected. Therefore, when the user inputs the distance from the main body case 1a to the projection surface 7, the color unevenness on the projection surface 7 can be automatically corrected without specifically specifying the color unevenness region 8.

  (3) The color unevenness correction unit 15 calculates a correction coefficient K based on the paint color of the main body case 1a, the reflection angle from the main body case 1a, and the distance from the main body case 1a to the projection plane 7, and the correction coefficient K Based on this, it is formed so that video signals of RGB colors before being applied to the R liquid crystal panel 17, G liquid crystal panel 18 and B liquid crystal panel 19 as light modulation elements are corrected. Therefore, by storing in advance the information necessary for color unevenness correction, color unevenness is automatically processed, and the user's labor is simplified.

(Modification)
The above embodiment can be modified as follows.
The horizontal correction coefficient Kh and the vertical correction coefficient Kv described above are stored in the horizontal RUT 32 and the vertical RUT 33 so as to correspond to the distance from the main body case 1a of the three-plate type wide-angle liquid crystal projector 1 to the projection surface such as the wall surface 3. It is preferable. And in this case, if the distance from the main body case 1a to the projection plane 7 can be set steplessly within a predetermined range, even when the set distance from the main body case 1a to the projection plane 7 is changed and attached, Color unevenness on the projection surface 7 due to reflection from the main body case 1a can be easily corrected.

  Further, the color unevenness correction unit 15 is configured to be able to adjust the horizontal correction coefficient Kh and the vertical correction coefficient Kv by a user menu, and the surface quality of the projection surface 7, a three-plate wide-angle liquid crystal projector It is preferable that the influence on the color unevenness due to the brightness of the space in which 1 is installed can be corrected based on the user's feeling. With this configuration, color unevenness can be corrected by visual color evaluation of the color unevenness region 8 by the user, so that user satisfaction can be improved.

  In the above-described embodiment, the horizontal correction coefficient Kh and the vertical correction coefficient Kv are constant correction coefficients at the respective positions in the color unevenness region 8. It is good also as what was set so that it may change gradually toward a location with little color change. In this way, color unevenness can be corrected more finely.

  In the above embodiment, the three-plate wide-angle liquid crystal projector 1 is shown as the wide-angle projection display apparatus. However, the present invention can also be applied to a liquid-crystal projector provided with other image light generation systems.

  In the above embodiment, the three-plate wide-angle liquid crystal projector 1 using the liquid crystal panel as the light modulation element is shown as the wide-angle projection display. However, the present invention is not limited to this. A projection projector having a generation system may be used. For example, a DLP (Digital Light Processing) (registered trademark of Texas Instruments (TI)) system projector may be applied to the present invention.

  The wide-angle projection image display apparatus according to the present invention can be used as an image display system in various facilities such as a home theater, a conference room, a training room, a classroom, an amusement hall, various exhibition rooms, and a studio.

1 is a block diagram of a control drive circuit in a three-plate type wide-angle liquid crystal projector as a wide-angle projection display apparatus according to an embodiment of the present invention. It is a block diagram inside a color unevenness correction part in the same 3 plate type wide angle liquid crystal projector. It is explanatory drawing of horizontal RUT and vertical RUT in the same 3 plate type wide angle liquid crystal projector. FIG. 2 is an installation view of a three-plate wide-angle liquid crystal projector for explaining occurrence of color unevenness, where (a) is a side view and (b) is a front view of a projection surface.

Explanation of symbols

  Kh, Kv, K... Correction coefficient, 1... 3 plate type wide angle liquid crystal projector (as a wide angle projection type image display device), 1a... Main body case, 4 ... projection lens, 5. ... projection plane, 8 ... color unevenness region, 15 ... color unevenness correction unit.

Claims (5)

  Wide-angle provided with a main body case whose surface is formed in a predetermined color, a light modulation element, a projection lens using a short focus lens, and an aspheric reflection mirror that reflects image light from the projection lens toward the projection surface A wide-angle projection-type image display apparatus comprising a color-unevenness correction unit that makes a color-unevenness region uniform due to light reflected from a main body case on a projection surface.   When the wide-angle projection display device is installed, the color unevenness correction unit calculates the position of the color unevenness region on the projection surface by inputting the distance from the main body case to the projection surface in the user menu. The wide-angle projection display apparatus according to claim 1, wherein the calculated uneven color region on the projection plane is corrected.   The color unevenness correction unit calculates a correction coefficient based on at least the color of the surface of the main body case, the reflection angle from the main body case, and the distance from the main body case to the projection surface, and is applied to the light modulation element based on the correction coefficient. 3. A wide-angle projection type image display device according to claim 2, wherein the image signals of each color of RGB before correction are corrected.   4. The wide-angle projection display apparatus according to claim 3, wherein the uneven color correction unit is configured to be able to adjust a correction coefficient by a user menu.   The color unevenness correction unit is formed so that a distance from the main body case to the projection plane can be set in a stepless manner within a predetermined range in the user menu. The wide-angle projection image display device described.

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