JP3772885B2 - Projector with trapezoidal distortion correction means - Google Patents

Description

  The present invention relates to a projector, and more particularly to a projector provided with trapezoidal distortion correction means.

  With the rapid development of liquid crystal technology and DLP (registered trademark) (digital light processing) technology, the size and performance of projectors have increased, and the use of projectors for video projection has expanded. It is also attracting attention as a large-sized display device that can replace this.

  However, unlike a display-type television, a projector has a problem that a video image is distorted due to the relative relationship between the projection optical axis of the projector and the screen because the screen is a screen or a wall. Disclosed is a method for adjusting the angle of a liquid crystal display unit according to an angle calculated from both detection results, having a detecting means for detecting an installation angle of a liquid crystal projector and a distance detecting means for detecting a distance between the liquid crystal projector and a projection target. (See Patent Document 1). In this case, it is necessary to mechanically adjust the angle of the liquid crystal display unit.

  On the other hand, when the vertical and horizontal inclinations of the screen with respect to the projection optical axis of the projector are known, a technique for projecting a distortion-free image on the screen by converting the coordinates of the frame memory of the projector has been put into practical use. Therefore, in order to measure the vertical tilt that is likely to cause distortion, the vertical tilt of the projector is detected by the gravity sensor on the assumption that the screen is installed vertically, and distortion correction corresponding to the tilt is performed. Projectors have already been disclosed and sold (see Patent Document 2).

In addition, a method of accurately measuring the tilt in the horizontal direction using a laser pointer and a digital camera having an image sensor, or projecting light from a plurality of light emitting elements through a single light projection lens onto a screen, and reflecting light Is received by a plurality of light receiving elements through a single light receiving lens, and a tilt angle is obtained by using the light receiving position and light intensity, or uniform luminance light is projected onto a screen from a projection lens of a projection device, A method has been developed in which the reflected light of the light is received by the light receiving element via one light guide unit and the tilt angle is obtained using the light receiving position and light intensity, and the obtained horizontal tilt angle and vertical tilt angle are obtained. The method of adjusting the output video and projecting the video with the trapezoidal distortion corrected on the screen has already been put into practical use.
Japanese Patent Laid-Open No. 9-281597 JP 2003-5278 A

  For high-end models, these adjustments are automated, but generally there are many models in which the trapezoidal distortion caused by the vertical and horizontal tilt angles is manually adjusted due to price issues. A projector is also put to practical use in which only the adjustment of the trapezoidal distortion caused by the tilt angle is automatically performed using the above-described gravity sensor, and the adjustment of the trapezoidal distortion caused by the horizontal direction tilt angle is manually performed.

  As described above, projectors having a trapezoidal distortion correction function are already common, and recently, there are many projectors capable of correcting not only in the vertical direction but also in the horizontal direction at the same time. However, if this adjustment is performed manually, each vertex of the projected image moves unpredictably. For this reason, there is a problem that it is difficult for the user to perform this adjustment and to project an image with a normal rectangle in accordance with a target position such as a screen.

  FIG. 5 is a schematic diagram of the output video of the display unit projected on the screen from the display unit by controlling the image processing LSI with the image control unit of the projector, where a) is a state in which the input video is not controlled, and b) The state in which the distortion in the vertical direction is controlled, and c) is the state in which the distortion in the horizontal direction is further controlled. In the figure, reference numeral 26 denotes a projectable range of the output video of the display unit, and reference numeral 25 denotes the output video.

  When the output video 25 in FIG. 5A in a state where the input video is not controlled is projected onto a screen whose upper part is inclined away from the projector, the video on the screen becomes a trapezoidal video with the upper width widened. When the output image corresponding to the vertical tilt angle is corrected by a manual method using a manual adjuster or an automatic method using a gravity sensor, the output image 25 has the shape shown in FIG. In the case of manual operation, the lower side of the image on the screen is usually adjusted to a desired position by zoom adjustment of the projection lens, and trapezoidal distortion is corrected by adjustment by a manual adjuster. When the output image 25 is projected on the screen in the state of FIG. 5B, the screen image becomes an image having upper and lower lines of the same length, and the screen is not inclined if the horizontal direction of the screen is not inclined with respect to the optical axis of the projector. The image becomes a normal rectangular image. However, if the right side of the screen is inclined in the direction away from the projector, a trapezoidal image in which the right end is longer than the left end is obtained. In this state, if the output video 25 is adjusted with a manual adjuster that correlates with the horizontal inclination angle, for example, the output video 25 is as shown in FIG. 5C. If the adjustment is appropriate, the output video 25 is projected onto the screen. Then, the screen image becomes an image with the same length on the left and right lines, and the screen image becomes a normal rectangular image.

  However, in reality, when this adjustment is performed, each vertex of the projected image on the screen moves unpredictably, so it is necessary for the user to perform this adjustment while combining the adjustment with the zoom adjustment and the tilt manual adjuster. It is not easy to project an image with a normal rectangle according to the target position.

  An object of the present invention is to provide a projector capable of manually and easily adjusting a trapezoidal distortion caused by a horizontal screen inclination of an image on a screen projected from a projector to a normal image.

A projector provided with the trapezoidal distortion correcting means of the present invention,
A projection apparatus having a display unit for projecting an image on a screen, an inclination angle output apparatus for forming an output value corresponding to an inclination angle of the projection optical axis of the projection apparatus with respect to the screen, and display according to an output value from the inclination angle output apparatus And a trapezoidal distortion correction unit having an image control unit that corrects the trapezoidal distortion of the video projected on the screen by controlling the output video of the unit.

The tilt angle output device includes a vertical tilt adjusting means for outputting an output value corresponding to the tilt angle in the vertical direction with respect to the screen of the projection optical axis to the image control unit, and an output corresponding to the manually tilted horizontal tilt angle. A horizontal direction inclination adjusting unit that outputs a value to the image control unit, and the image control unit includes a display unit corresponding to an inclination angle of the vertical projection optical axis with respect to the screen according to an output value from the vertical direction inclination adjusting unit. Control the output video and select the side closer to the projector in the left-right direction of the screen on which the image is projected based on the measurement value of the left and right distance sensors that are provided in the projector and measure the distance to the screen Fixed to the current position and moved to the screen of the horizontal projection optical axis by moving the remaining three sides corresponding to the output value from the manual horizontal tilt adjustment means. And performing control of the output image of the display section corresponding to the inclination angle of.

  The vertical direction inclination adjusting means may also manually output an output value corresponding to the vertical direction inclination angle to the image control unit, and the vertical direction inclination adjusting means outputs the projection light on the vertical plane including the projection optical axis of the projector. It may be a vertical direction tilt sensor that detects the tilt angle of the shaft.

  The left or right side of the fixed output image may be displayed by coloring on the projected screen image, or may be displayed by blinking of luminance.

The present invention has the effect of trapezoidal distortion by readily vertical and inclined in the horizontal direction of the screen 70 without an inclined manual adjustment complicated zoom adjustment wear adjustment.

  That is, after an adjustment value corresponding to the tilt angle with respect to the projection optical axis of the screen in the vertical direction is input and an output video from the image control unit is formed, any one of the left and right sides of the four sides surrounding the formed output video When a fixed side of the output image is provided on the side and an adjustment value corresponding to the tilt angle with respect to the projection optical axis of the screen in the horizontal direction is input, and this trapezoidal distortion caused by the horizontal tilt is corrected, this fixed side is This is because the output video is adjusted by moving the other three sides while being fixed at the current position of the projectable range of the output video.

  Next, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram of a projector provided with trapezoidal distortion correction means having a horizontal tilt manual adjuster according to the first embodiment of the present invention.

  As shown in FIG. 1, the projector 10 includes a projection device 21 having a projection lens 21 having a zoom adjustment mechanism and a display unit 22, an image control unit 23 that controls an image on the display unit 22, and vertical inclination manual adjustment. 51, a horizontal tilt manual adjuster 52, a zoom manual adjuster 53, and a central processing unit 60 for controlling the overall operation. The vertical tilt manual adjuster 51 controls the image controller 23. The image of the screen 70 is distorted by adjusting the output video output from the display unit 22 and adjusting the output video output from the display unit 22 under the control of the image control unit 23 by the horizontal tilt manual adjuster 52. The size of the image on the screen 70 is adjusted by the zoom adjustment of the projection lens by the zoom manual adjuster 53.

  The vertical tilt manual adjuster 51 and the horizontal tilt manual adjuster 52 may be dials or two push button switches whose output values can be changed depending on the pressing time. Any adjustment value corresponding to the tilt angle of the projection optical axis 27 may be used.

  The image control unit 23 converts the coordinates of the frame memory of the projector 10 according to the tilt angle in the vertical direction and the horizontal direction of the input screen 70 with respect to the projection optical axis 27 of the projector 10, thereby changing the output video of the display unit 22. It is a control unit that controls and projects an image without distortion from the display unit 22 onto the screen 70, and since a technique that has already been put into practical use is used as described above, detailed description thereof is omitted. This video distortion correction is automatically performed by the central processing unit 60 in a predetermined procedure.

  In the first embodiment, as in the prior art, first, an adjustment value corresponding to the tilt angle of the projection optical axis 27 of the screen 70 in the vertical direction is input by the vertical tilt manual adjuster 51 to tilt in the vertical direction. Next, an adjustment value corresponding to the inclination angle of the projection optical axis 27 of the screen 70 in the horizontal direction is input by the horizontal inclination manual adjuster 52 to correct the trapezoid distortion caused by the horizontal inclination. Correct distortion.

  FIG. 2 is a schematic diagram of the output video 25 of the display unit 22 projected on the screen 70 from the display unit 22 by controlling the image processing LSI with the image control unit 23 of the projector 10, and a) the input video is not controlled. The state, b) is a state in which the vertical distortion is controlled, and c) is a state in which the horizontal distortion is further controlled. In the figure, reference numeral 26 denotes a projectable range of the output video of the display unit, and reference numeral 25 denotes the output video.

  When the output video 25 in FIG. 2A in a state where the input video is not controlled is projected onto the screen 70 whose upper part is inclined away from the projector 10, the video on the screen 70 becomes a trapezoidal video with the upper width widened. When the output image 25 corresponding to the vertical inclination angle is corrected using the vertical inclination manual adjuster 51, the output image 25 becomes FIG. 2B, and when this output image 25 is projected onto the screen 70, the image of the screen 70 is displayed. The upper and lower lines are images of the same length, and if the horizontal direction of the screen 70 is not inclined with respect to the projection optical axis 27 of the projector 10, the image of the screen 70 is a normal rectangular image. In the adjustment method of the present invention based on the next horizontal inclination angle, the upper side of the output image 25 is brought close to the upper side of the screen 70, so that the adjustable range based on the next horizontal inclination angle is widened. However, if the right side of the screen 70 is inclined in the direction away from the projector 10, the image projected on the screen 70 is a trapezoidal image in which the right end is longer than the left end. . In the conventional example, the output video 25 is adjusted with a manual adjuster that correlates with the horizontal inclination angle in this state. However, in the present invention, the output video 25 is placed on any one of the four sides surrounding the output video 25. A fixed side 28 is provided.

  The fixed side 28 is inputted with an adjustment value corresponding to the tilt angle of the screen 70 with respect to the projection optical axis 27 in the horizontal direction from the horizontal tilt manual adjuster 52 by the image control unit 23, and is trapezoidal due to the tilt in the horizontal direction. When correcting the distortion, the output video 25 is adjusted to the current position of the projectable range 26 of the output video 25 and adjusted by moving the other three sides. Whether the fixed side is the left or right side is selected depending on whether the inclination of the screen 70 with respect to the projection optical axis 27 in the horizontal direction is farther toward the right or farther toward the left. The left side is defined as the fixed side 28 when separated on the right, and the right side is defined as the fixed side 28 when separated on the left. This is because the right side of the output video 25 moves downward as shown in FIG. 2 (c) when separated from the right, and the left side of the output video 25 moves downward when separated from the left. The adjustable range is widened by bringing the upper side of the output image 25 closer to the upper side of the screen 70, and the need for zoom adjustment in conjunction with the adjustment of the horizontal tilt manual adjuster 52 is reduced. Become. In this case, the left side of the output video 25 is set to move downward, but conversely, the fixed side 28 is fixed to the side where the screen 70 is separated, and the right side of the output video 25 is moved upward. It may be set. In this case, it is desirable that the lower side of the output image 25 is brought close to the lower side of the screen 70 as shown in FIG.

  Whether to select left or right is determined by whether the adjustment by the horizontal inclination manual adjuster 52 is performed as an adjustment when the right is separated or an adjustment when the left is separated. It is desirable for the device 52 to select and automatically select, but it may be selected manually. Further, the distance between the left and right of the screen 70 and the projector 10 is obtained by a simple sensor, and it is automatically determined which of the left and right is to be selected based on the result, and the fixed side 28 is clearly indicated on the screen 70 accordingly. May be.

  3 is an image when the output image of FIG. 2 is projected onto the screen 70, (a) is an image corresponding to FIG. 2 (b), and (b) corresponds to FIG. 2 (c). It is a picture. In the first embodiment, the trapezoidal distortion due to the tilt of the screen 70 in the vertical direction and the horizontal direction is easily adjusted without complicated zoom adjustment and manual tilt adjustment, as shown in FIG. A rectangular image is projected on the screen 70.

  Further, the horizontal tilt manual adjuster 52 can be easily operated by changing the color of the fixed side 28 on the screen 70 or by blinking the brightness.

  Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a schematic block diagram of a projector provided with trapezoidal distortion correction means having a horizontal tilt manual adjuster according to the second embodiment of the present invention. In the second embodiment, instead of the vertical tilt manual adjuster 51 of the first embodiment, a tilt sensor (G sensor) using an acceleration detection element that is also used for centering a machine or the like. Since the vertical direction tilt sensor 54 that precisely measures the tilt angle with respect to the direction of gravity and outputs it as numerical data is provided, the configuration and operation are the same as in the first embodiment. Are denoted by the same reference numerals and description of the same parts is omitted.

  The vertical tilt angle detected by the vertical tilt sensor 54 is output to the image control unit 23, and LSI control parameters corresponding to the vertical tilt are generated, as shown in FIG. 2B of the first embodiment. Output video is generated on the display unit. Since the subsequent generation of the fixed side 28 of the output video and the adjustment of the trapezoidal distortion based on the inclination of the screen 70 in the horizontal direction with respect to the projection optical axis 27 are the same as in the first embodiment, description thereof will be omitted. In this case, since the adjustment of the trapezoidal distortion based on the inclination of the screen 70 in the vertical direction with respect to the projection optical axis 27 is automatically performed, it is only necessary to manually adjust the horizontal direction. Become.

1 is a schematic block configuration diagram of a projector provided with a trapezoidal distortion correction unit having a horizontal inclination manual adjuster according to a first embodiment of the present invention. It is a schematic diagram of the output image of the display unit projected on the screen from the display unit by controlling the image processing LSI by the image control unit of the projector. a) is a state in which the input video is not controlled. b) is a state in which the distortion in the vertical direction is controlled. c) is a state in which the distortion in the horizontal direction is further controlled. It is an image when the output image of FIG. 2 is projected on the screen 70. (A) is an image corresponding to FIG. (B) is an image corresponding to FIG. It is a typical block block diagram of the projector provided with the trapezoid distortion correction | amendment means which has the horizontal direction inclination manual adjustment device of the 2nd Embodiment of this invention. It is a schematic diagram of the output video of the display unit projected from the display unit onto the screen by controlling the image processing LSI with the image control unit of the projector of the conventional example. a) is a state in which the input video is not controlled. b) is a state in which the distortion in the vertical direction is controlled. c) is a state in which the distortion in the horizontal direction is further controlled.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Projector 20 Projection apparatus 21 Projection lens 22 Display part 23 Image control part 25 Output image 26 Projectable range 27 Projection optical axis 28 Fixed side of output image 51 Vertical inclination manual adjuster 52 Horizontal direction inclination manual adjuster 53 Zoom manual adjustment 54 Vertical tilt sensor 60 Central processing unit 70 Screen

Claims (5)

A projection apparatus having a display unit for projecting an image on a screen, an inclination angle output apparatus for forming an output value corresponding to an inclination angle of the projection optical axis of the projection apparatus with respect to the screen, and the output from the inclination angle output apparatus In a projector comprising a trapezoidal distortion correction means having an image control unit that corrects a trapezoidal distortion of the video projected on the screen by controlling an output video of the display unit according to a value,
The tilt angle output device includes:
A vertical direction inclination adjusting means for outputting an output value corresponding to a vertical inclination angle of the projection optical axis with respect to the screen to the image control unit;
A horizontal inclination adjusting means for outputting an output value corresponding to a horizontal inclination angle inputted manually to the image control unit;
The image control unit
In accordance with the output value from the vertical direction tilt adjustment means, control the output video of the display unit corresponding to the tilt angle of the vertical projection optical axis with respect to the screen,
The side edge closer to the projector lateral direction of the screen image is projected, by selecting based on the measurement values of the right and left distance sensor for measuring a distance to the screen provided on the projector and the display unit Fixed at the current position of
The output video of the display unit corresponding to the tilt angle of the horizontal projection optical axis with respect to the screen is controlled by the movement of the remaining three sides corresponding to the output value from the horizontal tilt adjusting means manually. A projector provided with a trapezoidal distortion correcting means.   The projector including the trapezoidal distortion correction unit according to claim 1, wherein the vertical direction inclination adjustment unit also manually outputs an output value corresponding to a vertical direction inclination angle to the image control unit.   2. The trapezoidal distortion correction unit according to claim 1, wherein the vertical direction inclination adjustment unit is a vertical direction inclination sensor that detects an inclination angle of the projection optical axis on a vertical plane including the projection optical axis of the projector. Projector. Left or right side of the output image to be fixed is indicated by colored on projected the screen image, comprises a keystone distortion correction means according to any one of claims 1 to 3 Projector. Left or right side of the output image to be fixed is indicated by flashing luminance on projected the screen image, the keystone distortion correction means according to any one of claims 1 to 3 With projector.

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