JP2008083415A - Projection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection device capable of easily performing fine control of position of an optical modulation element used in the projection device from the outer part of the projection device. <P>SOLUTION: The projection device is provided with: an illumination optical system 11 of lighting light; the optical modulation element 20 which converts the light made incident from the illumination optical system 11 into image light and emits the image light; and an image forming optical system 24 of projecting the image light. The projection device is further provided with: a position control means 80 for controlling the position of the optical modulation element 20; an image light drawing means 50 for drawing a part of the image light emitted from the optical modulation element 20; an image forming part 56 for image-forming the drawn image light; and a light detection means 58 for detecting an optical modulation element image which is image-formed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection apparatus that projects an image on a screen, and more particularly, to a projection apparatus that corrects trapezoidal distortion of a projected image and performs focus adjustment.

  2. Description of the Related Art A projection apparatus that projects an image on a screen uses a DMD (Digital Micromirror Device) as a light modulation element that generates a projection image. The DMD is a light modulation element that receives time-division light and generates a video image by time mixing by controlling the reflection direction and the reflection time of the incident light for each pixel.

  Since the light reflected by the DMD has high directivity unlike the scattered light, it is necessary to match the predetermined default angle, for example, to coincide with the optical axis of the imaging optical system. When DMD is used as a light modulation element, there are few errors allowed for this default angle, so it is necessary to adjust the light modulation element to the default angle with high precision, such as when the light modulation element is replaced as well as during manufacturing. .

Conventionally, in order to satisfactorily correct the trapezoidal distortion of an image without occurrence of jaggies, the DMD element mounting base is fixed on a substantially disc-shaped gear, and the manual operation means geared to the gear is used for the DMD element mounting base. A projection display device that performs angle adjustment is known (see, for example, Patent Document 1).
JP 2004-45733 A

  The projection type display device of Patent Document 1 is an invention in which the angle of the DMD element mounting substrate is adjusted by manual operation means while observing the projected image by the operator. Therefore, when adjusting the angle of the DMD element, it is necessary to project an image on a screen or the like, and it is necessary for the operator to adjust the angle of the DMD element mounting board by operating the manual operation means each time. there were.

  In addition, when a predetermined angle difference with respect to the optical axis of the imaging optical system is previously set as the default angle of the light modulation element, the light reflected by the light modulation element is within the incident range of the imaging optical system. Therefore, in addition to adjusting the angle of the light modulation element, it is necessary to adjust the horizontal position of the light modulation element with respect to the optical axis of the imaging optical system.

  Further, when the angle of the light modulation element deviates from the default angle, such as when the projection apparatus is used for a long period of time, the projection engine is disassembled and an optical engine including the imaging optical system and the light modulation element After the portion was exposed, there was a problem in that it was necessary to adjust the position of the light modulation element delicately. Further, a skilled worker is required to adjust the position including the angle of the light modulation element, which causes a problem that the adjustment takes time.

  In order to solve the above problem, a projection apparatus according to claim 1 includes an illumination optical system that irradiates light to the light modulation element, a light modulation element that converts light incident from the illumination optical system into image light, and emits the light. A projection apparatus comprising an imaging optical system for projecting image light, wherein the position adjusting means adjusts the position of the light modulation element, and image light extraction for extracting part of the image light emitted from the light modulation element Means, an image forming unit that forms an image of the extracted video light, and a light detection unit that detects the imaged light modulation element image.

  According to a second aspect of the present invention, a photoelectric conversion element that converts an image formed into an electrical signal is used as the light detection means, and a command for controlling the position of the light modulation element by using the electrical signal is positioned. And a position control means for outputting to the adjusting means.

  According to a third aspect of the present invention, the position control means acquires the entire image of the light modulation element formed on the photoelectric conversion element, detects a deviation from the default position, and controls the position of the light modulation element. A command is output to the position adjusting means.

  According to a fourth aspect of the present invention, there is provided a pattern generator for generating a test pattern for adjusting the position of the light modulation element, and the test pattern is input to cause the light modulation element to generate video light of the test pattern. And a position control means for outputting a command for controlling the position of the light modulation element to the position adjustment means using a test pattern image formed on the photoelectric conversion element. It is characterized by.

  According to a fifth aspect of the present invention, the position adjusting means includes angle adjusting means for adjusting the angle between the normal line of the light modulation element and the optical axis of the imaging optical system by tilting the light modulation element. It is characterized by providing.

  According to a sixth aspect of the present invention, the position adjusting means adjusts the position of the imaging optical system relative to the optical axis by moving the light modulating element parallel or perpendicular to the surface of the light modulating element. Means are provided.

  The invention according to claim 7 is characterized in that a piezoelectric element is used for the actuator of the position adjusting means.

  The invention described in claim 8 is characterized in that a linear motor is used as the actuator of the position adjusting means.

  The invention according to claim 9 includes, as the imaging optical system, a first relay lens disposed on the light modulation element side and a second relay lens disposed on the side from which the projected image is emitted. Using the lens group, the image light extraction means extracts a part of the image light generated by the light modulation element from between the first relay lens and the second relay lens.

  According to a tenth aspect of the present invention, as the imaging optical system, a first relay lens disposed on the light modulation element side, a diaphragm disposed at a subsequent stage of the first relay lens, and adjusting the amount of light; Using a lens group including a second relay lens arranged on the side from which the projection image is output after the stop, the image light extraction means generates a light modulation element between the stop and the second relay lens. It is characterized by extracting a part of the image light.

  According to an eleventh aspect of the present invention, as the imaging optical system, a first relay lens disposed on the light modulation element side, a diaphragm disposed at a subsequent stage of the first relay lens, and adjusting the amount of light, Image light extraction using a lens group that includes a reflecting mirror that is arranged at the rear stage of the stop to change the direction of light irradiation and a second relay lens that is arranged on the side of emitting the projected image at the rear stage of the reflecting mirror. The means is characterized in that a part of the image light generated by the light modulation element is extracted from a part of the reflecting mirror.

  The invention described in claim 12 is characterized in that a screen mat for displaying an image is used as the light detecting means.

  According to the first or fifth aspect of the present invention, the position adjusting means for adjusting the angle between the normal line of the light modulation element and the optical axis of the imaging optical system by tilting the light modulation element, and the light Image light extraction means for extracting a part of the image light emitted from the modulation element, an image forming unit for forming an image of the extracted image light, and a light detection means for detecting the imaged light modulation element image Therefore, a part of the image light generated by the light modulation element can be extracted by the image light extraction means, and the image light can be taken into the light detection means by the imaging unit constituted by a lens or the like. Thereby, an image similar to the image projected on the screen can be formed in the projection apparatus.

  Then, while detecting the image formed, the position adjustment means is used to adjust the angle between the normal of the light modulation element and the optical axis of the image forming optical system, thereby reducing the trapezoidal distortion of the projected image. Adjustments can be made. Also, by adjusting the angle between the optical axis and the normal line of the light modulation element, the image light is transmitted along the optical axis of the projection lens group. It is possible to prevent a problem that light quantity loss occurs.

  According to the invention of claim 1 or claim 6, the position adjusting means for adjusting the position of the imaging optical system with respect to the optical axis by moving the light modulating element parallel or perpendicular to the surface of the light modulating element. An image light extraction unit that extracts a part of the image light emitted from the light modulation element, an image forming unit that forms an image of the extracted image light, and a light detection unit that detects the imaged light modulation element image Therefore, the image light extraction means extracts a part of the image light generated by the light modulation element, and the image light can be taken into the light detection means by an imaging unit such as a lens. Thereby, an image similar to the image projected on the screen can be formed in the projection apparatus.

  Then, the position of the image light incident on the image forming optical system can be adjusted by moving the light modulation element in parallel using the position adjusting means while detecting the formed image. In addition, by adjusting the position of the light modulation element with respect to the optical axis of the imaging optical system, the image light is transmitted within the incident range of the projection lens group. It is possible to prevent the problem of causing loss. Furthermore, it is possible to perform focus adjustment by moving the light modulation element perpendicularly to the light modulation element surface using the position adjusting means while detecting the formed image.

  According to a second aspect of the present invention, a photoelectric conversion element that converts an image formed into an electrical signal is used as the light detection means, and a command for controlling the position of the light modulation element by using the electrical signal is provided. Since the position control means for outputting to the position adjusting means is provided, it is possible to automatically adjust the position of the image light incident on the imaging optical system.

  Therefore, for example, even when the angle between the normal line of the light modulation element and the optical axis of the imaging optical system changes due to thermal deformation of the housing of the projection apparatus, etc., it automatically becomes a predetermined angle. Adjustment to maintain can be performed, and deviation and deformation of the projected image can be prevented. Further, the adjustment of the projection position caused when the parallel position with respect to the optical axis of the imaging optical system is inappropriate can be automatically performed.

  According to the invention of claim 3, the position control means acquires the entire image of the light modulation element formed on the photoelectric conversion element, detects the deviation from the default position, and controls the position of the light modulation element. Since the command is output to the position adjusting means, the inclination and parallel position of the light modulation element can be adjusted so that the entire image of the light modulation element acquired from the photoelectric conversion element is at the default position. As a result, it is possible to project an easy-to-view video with reduced distortion of the projected video.

  According to a fourth aspect of the present invention, a pattern generation unit that generates a test pattern for adjusting the position of the light modulation element, and the test pattern is input to cause the light modulation element to generate video light of the test pattern. And a position control means for outputting a command for controlling the position of the light modulation element to the position adjustment means using a test pattern image formed on the photoelectric conversion element. Thus, the inclination and position of the light modulation element can be adjusted using the video of the test pattern acquired from the photoelectric conversion element. Accordingly, the image light generated by the light modulation element can be incident on the center of the projection range of the imaging optical system. Therefore, it is possible to project an image with little distortion by effectively using the projection range of the imaging optical system.

  According to the invention of claim 7, since the piezoelectric element is used as the actuator of the position adjusting means, the fine angle adjustment between the normal of the light modulation element and the optical axis of the imaging optical system, or The fine parallel position of the light modulation element can be adjusted using an electric signal. Further, the position of the light modulation element can be adjusted by remote control.

  According to the invention of claim 8, since the linear motor is used as the actuator of the position adjusting means, the adjustment of the angle between the normal line of the light modulation element and the optical axis of the imaging optical system, or the light Adjustment of the parallel position of the modulation elements can be performed using electrical signals. Further, the position of the light modulation element can be adjusted by remote control.

  According to the invention of claim 9, the imaging optical system includes a first relay lens arranged on the light modulation element side and a second relay lens arranged on the side emitting the projection image. Since the image light extraction means is configured to extract a part of the image light generated by the light modulation element from between the first relay lens and the second relay lens using the lens group, the imaging optical An image similar to the projection image generated by the system can be imaged in the projection device to adjust the tilt and parallel position of the light modulation element.

  According to the invention of claim 10, as the imaging optical system, a first relay lens disposed on the light modulation element side, a diaphragm disposed at a subsequent stage of the first relay lens, and adjusting the amount of light, Using a lens group including a second relay lens arranged on the side from which the projection image is output after the stop, the image light extraction means generates a light modulation element between the stop and the second relay lens. Since a part of the projected image light is extracted, the same image as the projection image generated by the imaging optical system is imaged in the projection device to adjust the tilt and parallel position of the light modulator. can do.

  According to the invention of claim 11, as the imaging optical system, a first relay lens disposed on the light modulation element side, and a diaphragm disposed at the subsequent stage of the first relay lens to adjust the amount of light, Image light extraction using a lens group that includes a reflecting mirror that is arranged at the rear stage of the stop to change the direction of light irradiation and a second relay lens that is arranged on the side of emitting the projected image at the rear stage of the reflecting mirror. Since the means is configured to extract a part of the image light generated by the light modulation element from a part of the reflecting mirror, the condenser lens and the light detecting means are arranged using the space behind the reflecting mirror. Therefore, it is possible to provide a small projection device that can adjust the inclination and parallel position of the light modulation element.

  According to the invention of claim 12, since the screen mat on which an image is formed is used as the light detection means, the user adjusts the position of the light modulation element while looking at the screen mat provided in the projection apparatus. can do.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an internal configuration of a projection apparatus according to an embodiment of a video generation apparatus according to the present invention.

  The projection apparatus according to the present embodiment is an apparatus that projects light onto a projection surface (screen) so that a light modulation element generates an image using light emitted from a light source and can be observed by a user.

  The illumination optical system 11 of the projection apparatus 10 shown in FIG. 1 has a light source 12, a reflector 13 that reflects and collects light emitted from the light source 12, and a plurality of filters that transmit light of a specific wavelength. The color wheel 16 is divided, the line tunnel 18 for mixing the illumination light to obtain uniform illumination light, and the condenser lens 14 for condensing the illumination light from the light tunnel 18.

  In addition, the projection apparatus 10 includes a prism 22 that causes the illumination light emitted from the illumination optical system 11 to enter the light modulation element 20 and the image light generated by the light modulation element 20 to enter the imaging optical system 24, and illumination. A light modulation element 20 that converts the light incident from the optical system 11 into image light and emits it, and an imaging optical system 24 that projects an image generated by the light modulation element 20 onto a screen 26 are provided.

  As the light modulation element 20, a DMD (Digital Micromirror Device) that generates an image by making light incident on the imaging optical system 24 using a movable mirror provided for each pixel can be used.

  In the embodiment shown in FIG. 1, the imaging optical system 24 includes a first relay lens 40 disposed on the light modulation element 20 side, and a diaphragm 42 disposed downstream of the first relay lens 40 to adjust the amount of light. A reflecting mirror 44 disposed at the rear stage of the stop 42 to change the direction of light irradiation, and a second relay lens 46 disposed on the side from which the projected image of the rear stage is emitted from the reflecting mirror 44. The image generated by the modulation element 20 can be projected onto the screen 26.

  In the embodiment shown in FIG. 1, a part of the reflecting mirror 44 is provided with the image light extraction means 50 that transmits the image light, and a part of the image light generated by the light modulation element 20 is extracted. Yes. Since the reflecting mirror is disposed in the vicinity of the stop, even if a portion that transmits light is provided in a part of the reflecting mirror, the image projected on the screen is not affected by the occurrence of some chipping or unevenness. A part of the image light extracted by the image light extraction means 50 is incident on the image forming unit 56 provided in the subsequent stage. The imaging unit 56 focuses the incident video light and forms an image on the light detection unit 58. In the embodiment shown in FIG. 1, a convex lens is used as the imaging unit 56, but the present invention is not limited to this lens configuration, and a concave mirror that collects image light and forms an image on the light detection means 58. An image forming unit such as can be used.

  As the light detection means 58, a photoelectric conversion element such as a screen mat for displaying an image, a CCD (Charge Coupled Devices) for converting the formed image into an electric signal, an area sensor, a line sensor, a photodiode array, or the like is used. Can do.

  In the embodiment of the present invention, in order to prevent the image light generated by the light modulation element 20 from being out of the incident range of the imaging optical system 24, the light amount of the projected image is lost and becomes dark. Position adjusting means 80 for adjusting the position of the element 20 is provided.

  In the embodiment shown in FIG. 1, an angle adjusting unit 64 that adjusts an angle θ between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24 by tilting the light modulation element 20, Position adjusting means 78 that adjusts the position of the imaging optical system 24 with respect to the optical axis by moving the modulation element 20 in the X direction or Y direction (not shown) parallel to the image generation surface of the light modulation element 20. And.

  In the embodiment shown in FIG. 1, a linear motor or an actuator is employed as the position adjusting unit 78, and the mounting base 70 for mounting the position adjusting unit 80 and the light modulation element 20 on the projection apparatus 10 side is disposed on the mounting base 70. The driving coil 72, the magnet 74 arranged so as to face the driving coil 72 with a predetermined gap, and the light modulation element 20 are configured to be movable in the X direction by fixing the magnet 74. And a carriage 76.

  Further, in the embodiment shown in FIG. 1, the angle adjusting means 64 is disposed between the carriage 76 and the light modulation element 20, and includes one to three sets of piezoelectric elements that move the light modulation element 20 in the Z direction by expansion and contraction. And an elastic body 62 that absorbs an angle difference between the expansion / contraction means 60 and the light modulation element 20 when the angle θ of the light modulation element 20 is inclined.

  In the embodiment shown in FIG. 1, a linear motor actuator motor is employed as the position adjusting means 78, but an ultrasonic motor, a piezoelectric element, and other actuators can be used. Moreover, although the piezoelectric element is employ | adopted as the angle adjustment means 64, a linear motor, an ultrasonic motor, and another actuator can be used.

  FIG. 2 is a block diagram of a signal processing system of the projection apparatus 10. In addition, about the component same as the component shown in FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 2, the projection device 10 includes a lamp control circuit 195 that outputs a light emission signal for sequentially emitting light of a plurality of types of primary colors in a time-division manner, and a video signal for generating an image. An image processing unit 196 that outputs a signal, an optical element drive unit 10 that outputs a control signal for controlling the light modulation element 20, a position control unit 197 that outputs a command for controlling the position adjusting unit 80, and An input unit 170 including buttons and switches for inputting various information from a person, and a CPU 180 for controlling the entire projection apparatus 10 are provided.

  In addition, the projection apparatus 10 includes a RAM 181 that is used as a work area when the CPU 180 executes processing, a ROM 183 that records various information such as processing programs and constants executed by the CPU 180, default image data, and the like, and an image processing unit 196. And a frame memory 184 for temporarily storing the image data to be output.

  The peripheral circuits including the CPU 180, the lamp control circuit 195, the image processing unit 196, the position control unit 197, the RAM 181 and the ROM 183 in the projection apparatus 10 are connected by a bus 199 and are based on a processing program executed by the CPU 180. Thus, it is possible to control each peripheral circuit. The processing program executed by the CPU 180 can be provided by a recording medium or communication. Each peripheral circuit can also be constituted by an ASIC or the like.

  In the embodiment shown in FIG. 2, an embodiment is shown in which an image is formed as the light detection means 58 and a screen mat for visual observation is used. On the screen mat, all or a part of the image equivalent to the image projected by the projection device 10 can be imaged and displayed. Therefore, the user can adjust the position of the light modulation element 20 by operating the input unit 170 while viewing the display of the screen mat provided in the projection apparatus 10.

  FIG. 3 is a diagram illustrating an embodiment of an operation unit of the input unit 170.

  In the embodiment shown in FIG. 3, as the operation unit of the input unit 170, the cross button 34 for adjusting the angle between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24, and the surface of the light modulation element 20 are used. A cross button 36 for adjusting the parallel position and a cursor button 38 for adjusting the focus position for moving the light modulation element 20 in the Z direction shown in FIG. 1 are provided.

  When the user operates the cross button 34 for angle adjustment, the CPU 180 reads the information from the input unit 170 via the bus 199, and outputs an output of a control command based on the user's operation to the position control unit 197. Output to. The position control unit 197 outputs a control signal for tilting the light modulation element 20 in a predetermined direction by a predetermined angle to the expansion / contraction unit 60 of the angle adjustment unit 64 based on the information acquired from the CPU 180.

  The one or more angle adjusting means 64 to which the control signal is input performs a predetermined amount of expansion / contraction operation to move the light modulation element 20 in the θ direction shown in FIG. 1 or in the φ direction (not shown) perpendicular to the θ direction. Set to a predetermined angle.

  Accordingly, the user operates the angle adjusting cross button 34 provided in the input unit 170 while viewing the image formed on the screen mat provided in the projection device 10, so that the light modulation element 20 is moved. The irradiation direction of the generated image light can be adjusted within a predetermined range of the imaging optical system 24.

  When the user operates the cursor button 38 for adjusting the in-focus position, the CPU 180 reads the information from the input unit 170 via the bus 199, and outputs an output of a control command based on the user's operation. It outputs to the control means 197. The position control means 197 outputs a control signal for moving the light modulation element 20 by a predetermined amount in the Z direction shown in FIG. 1 to the expansion / contraction means 60 of the angle adjustment means 64 based on the information acquired from the CPU 180.

  The one or more angle adjusting means 64 to which the control signal is input performs a predetermined amount of expansion / contraction operation to move the light modulation element 20 by a predetermined displacement amount in the Z direction shown in FIG. Therefore, the user can adjust the in-focus position by operating the in-focus position adjusting cursor button 38 provided in the input unit 170.

  When the user operates the cross button 36 for adjusting the parallel position, the CPU 180 reads the information from the input unit 170 via the bus 199, and outputs the output of the control command based on the operation of the user. It outputs to the control means 197. The position control unit 197 outputs a control signal for displacing the light modulation element 20 in a predetermined direction by a predetermined amount to the coil 72 of the position adjustment unit 78 based on the information acquired from the CPU 180.

  The one or more coils 72 to which the control signal is input generate a predetermined thrust and move the light modulation element 20 in the X direction shown in FIG. 1 or a Y direction (not shown) perpendicular to the X direction by a predetermined amount. To do.

  When an element such as DMD having strong directivity of image light is used as the light modulation element 20 of the projection apparatus 10, an attachment error between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24. If there is an angle difference due to the tolerance of parts or parts, a part of the image light generated by the light modulation element 20 may be out of the incident range of the imaging optical system 24. When a part of the image light generated by the light modulation element 20 deviates from the incident range of the imaging optical system 24, the periphery of the image to be projected becomes dark or pixels that are not projected are generated.

  Therefore, in the embodiment shown in FIG. 1, a part of the image light generated by the light modulation element 20 is imaged on the light detection means 58 inside the projection apparatus 10, and the image formed on the light detection means 58 is detected. However, the input means 170 is operated to adjust the angle between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24 and the position parallel to the surface of the light modulation element 20, thereby modulating the light. The image light generated by the element 20 can be incident on a predetermined range of the imaging optical system 24.

  FIG. 4 is a diagram showing another embodiment of the light detection means 58 in the projection apparatus 110 according to the embodiment of the present invention. In addition, about the component same as the component shown in FIG. 2, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the embodiment shown in FIG. 4, as the light detection means 58, a photoelectric conversion device such as a CCD (Charge Coupled Devices), an area sensor, a line sensor, or a photodiode array that converts an image formed into an electric signal is used to detect light. A control unit 151 that performs processing such as conversion of video signals output by the means 58 into image data, and a display unit 172 that inputs video signals and displays images are provided.

  The image formed on the light detection means 58 is converted into a video signal by the light detection means 58, and the control unit 151 converts the video signal into image data so that the CPU 180 can read it. Further, the CPU 180 outputs image data for display to the display unit 172 so that an image formed on the light detection means 58 can be displayed.

  Further, default image data obtained when the light modulation element 20 is attached at a normal position is stored in the ROM 183 in advance, and the CPU 180 obtains an entire image of the light modulation element 20 acquired from the light detection unit 58 or By comparing a part of the image data with the image data stored in advance in the ROM 183, the amount of deviation between the position of the light modulation element 20 and the default position can be detected.

  Then, the CPU 180 calculates an angle between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24 or a position shift amount of the light modulation element 20 from the detected deviation amount of the light modulation element 20. Thus, a command for correcting the deviation amount is output to the position adjusting means 80 via the position control means 197.

  By configuring the projection device 110 in this way, it is possible to automatically adjust the image light generated by the light modulation element 20 to enter the central portion of the incident range of the imaging optical system 24.

  Also, as shown in FIG. 4, a pattern generation unit 198 that generates a test pattern suitable for calibrating the position of the light modulation element 20 is provided, and the image processing unit 196 inputs the test pattern, and the optical element drive The video signal of the test pattern may be output to the unit 10. With this configuration, the tilt and position of the light modulation element 20 can be adjusted efficiently and accurately.

  For example, a description will be given along an embodiment in which the position of the light modulation element 20 is adjusted using a light amount distribution in which the luminance near the center increases as shown in FIG. FIG. 6 is a diagram showing the amount of light on the X-axis output by the light detection means 58 that has received the test pattern shown in FIG.

  It is assumed that the light modulation element 20 generates the test pattern shown in FIG. 5, and the light detection means 58 has acquired light amount data that is shifted by ΔX from the default image data, as shown in FIG. The CPU 180 calculates a deviation amount ΔX in the X direction from the default image data and the image data acquired from the light detection means 58, and calculates the normal between the light modulation element 20 and the optical axis of the imaging optical system 24. A command for correcting the angle or the position of the light modulation element 20 is output to the position adjusting means 80 via the position control means 197. In this way, it is possible to automatically adjust the image light generated by the light modulation element 20 to enter the central portion of the incident range of the imaging optical system 24.

  Next, an embodiment in which the position of the light modulation element 20 is adjusted using a test pattern provided with markers at four corners as shown in FIG. 7 as a test pattern will be described.

  Assume that the light modulation element 20 generates the test pattern shown in FIG. 7, and the light detection means 58 acquires image data distorted in a trapezoidal shape with respect to the default image data as shown in FIG. The CPU 180 calculates a trapezoidal distortion degree ΔX from the default image data and the image data acquired from the light detection means 58, and the angle between the normal line of the light modulation element 20 and the optical axis of the imaging optical system 24. Alternatively, a command for correcting the position of the light modulation element 20 is output to the position adjusting unit 80 via the position control unit 197. In this way, the adjustment that reduces the trapezoidal distortion of the image projected by the projection device 110 can be automatically performed.

  Next, another embodiment of the image light extraction unit according to the embodiment of the present invention will be described.

  FIG. 9 is a diagram showing an embodiment of a projection apparatus 210 that uses a small extraction mirror as the image light extraction means 50. In addition, about the component same as the component shown in FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the embodiment shown in FIG. 1, an image light extraction means 50 that transmits image light is provided in a part of the reflecting mirror 44, and a part of the image light generated by the light modulation element 20 is extracted. However, as shown in FIG. 9, an extraction mirror 52 (image light extraction means) for extracting a part of the image light is provided after the stop 42 so that a part of the image light generated by the light modulation element 20 is extracted. You may comprise. The image light extracted by the extraction mirror 52 is incident on the image forming unit 56 provided in the subsequent stage and is imaged on the light detecting means 58.

  FIG. 10 is a plan view showing another embodiment of the position adjusting means 80 according to the embodiment of the present invention, in which the light modulation element 20 is viewed from the side from which the image light is emitted to the imaging optical system 24. FIG. FIG. 11 is a cross-sectional view of the position adjusting unit 80, the light modulation element 20, and the mounting base 70 shown in FIG. 10 cut along A-A '.

  In the embodiment shown in FIGS. 10 and 11, four position adjusting means 79 are provided between the casing 82 and the light modulation element 20. As the position adjusting means 79, for example, an actuator such as a piezoelectric element can be used. By controlling the length of the position adjusting means 79 by the voltage applied to the piezoelectric element, the light modulation element 20 can be moved in the X direction and the Y direction with respect to the casing 82.

  In the embodiment shown in FIGS. 10 and 11, four expansion / contraction means 60 are provided between the mounting base 70 and the light modulation element 20. As the expansion / contraction means 60, for example, an actuator such as a piezoelectric element can be used. By controlling the length of the expansion / contraction means 60, the light modulation element 20 can be moved in the Z direction with respect to the mounting base 70, or the light modulation element 20 can be tilted with respect to the mounting base 70.

  FIG. 12 shows a light modulation element 20 in the projection apparatus according to the embodiment of the present invention, an imaging unit 56 that extracts a part of the image light generated by the light modulation element 20 and focuses it on the light detection means 58, 3 is a side view of an extraction imaging optical system 54 showing a light modulation element image 59 imaged on a light detection means 58. FIG. FIG. 13 is a diagram showing the light detection means 58 and a light modulation element image 59 that forms an image on the light detection means 58 when the light modulation element 20 exists at the default position.

  As shown in FIG. 13, when the light modulation element 20 exists at the default position D, a rectangular light modulation element image similar to the image generated by the light modulation element 20 is formed at the center of the light detection means 58. 59 is imaged.

  FIG. 14 is a side view of the extraction imaging optical system 54 when the light modulation element 20 is inclined by the angle θ with respect to the default position D. FIG. 15 is a diagram showing a light modulation element image 59A formed on the light detection means 58 when the light modulation element 20 is inclined by an angle θ with respect to the default position D.

  As shown in FIG. 15, when the light modulation element 20 is inclined by the angle θ with respect to the default position D, the light modulation element image 59 </ b> A formed on the light detection means 58 has a trapezoidal shape. When the light modulation element image 59A having the trapezoidal shape is obtained, a command to return the light modulation element 20 by the angle θ using the difference in shape from the default light modulation element image 59D (degree of trapezoidal distortion). Is output to the angle adjusting means 64 to adjust the position of the light modulation element 20. Then, the light modulation element image 59A is adjusted to be equal to the default light modulation element image 59D.

  FIG. 16 is a side view of the extraction imaging optical system 54 in the case where the light modulation element 20 exists forward (exit side) by a distance of ΔZ with respect to the default position D. FIG. 17 is a diagram showing a light modulation element image 59B formed on the light detection means 58 when the light modulation element 20 exists ahead of the default position D by a distance of ΔZ. .

  As shown in FIG. 17, when the light modulation element 20 exists ahead of the default position D by a distance of ΔZ, the light modulation element image 59B formed on the light detection means 58 is the default. The rectangular shape is larger than the light modulation element image 59D. In this way, when a rectangular light modulation element image 59B larger than the default light modulation element image 59D is obtained, the difference in shape (degree of the size of the rectangle) from the default light modulation element image 59D is obtained. Then, a command for returning the light modulation element 20 backward by ΔZ is output to the position adjusting means 80 to adjust the position of the light modulation element 20 in the Z direction. Then, the light modulation element image 59B is adjusted to be equal to the default light modulation element image 59D.

  FIG. 18 is a side view of the extraction imaging optical system 54 in the case where the light modulation element 20 exists behind the default position D by a distance of ΔZ (on the opposite side to the emission side). FIG. 19 is a diagram showing a light modulation element image 59C formed on the light detection means 58 when the light modulation element 20 exists behind the default position D by a distance of ΔZ. is there.

  As shown in FIG. 19, when the light modulation element 20 exists behind the default position D by a distance of ΔZ, the light modulation element image 59C formed on the light detection means 58 is the default. The rectangular shape is smaller than the light modulation element image 59D. In this way, when a rectangular light modulation element image 59C smaller than the default light modulation element image 59D is obtained, the difference in shape (degree of rectangular size) from the default light modulation element image 59D is obtained. Then, a command to return the light modulation element 20 forward by ΔZ is output to the position adjusting means 80 to adjust the position of the light modulation element 20 in the Z direction. Then, the light modulation element image 59C is adjusted to be equal to the default light modulation element image 59D.

  FIG. 20 shows an extraction image formed when the light modulation element 20 is shifted from the default position D by a distance of ΔX and ΔY (the Y direction is not shown because it is the front and back direction of the paper surface of FIG. 20). 3 is a side view of the optical system 54. FIG. FIG. 21 shows the shape of a light modulation element image 59E formed on the light detection means 58 when the light modulation element 20 is shifted from the default position D by a distance of ΔX and ΔY. It is.

  As shown in FIG. 21, when the light modulation element 20 is shifted from the default position D by a distance of ΔX and ΔY, the light modulation element image 59E formed on the light detection means 58 is the default. The light modulation element image 59D is substantially equal in size and has a rectangular shape with a different position. As described above, when a rectangular light modulation element image 59E having a position different from that of the default light modulation element image 59D is obtained, a difference in position from the default light modulation element image 59D is used to obtain the light modulation element. A command for moving 20 by ΔX and ΔY is output to the position adjusting means 79 to adjust the position of the light modulation element 20 in the X and Y directions. Then, adjustment is made so that the light modulation element image 59E is positioned at the position of the default light modulation element image 59D. In this way, the position of the light modulation element 20 can be controlled using the light modulation element image 59.

  Next, the position adjustment processing of the light modulation element using the projection apparatus according to the embodiment of the present invention will be described using the flowchart shown in FIG.

  FIG. 22 is a flowchart of the position adjustment process of the light modulation element using the projection apparatus according to the embodiment of the present invention.

  For example, when the projector 110 (see FIG. 4) is turned on, the process executed by the CPU 180 branches to the position adjustment process shown in FIG. 22, and is described as S102 “test pattern projection” (hereinafter abbreviated as S102). ).

  In S <b> 102 “Test pattern projection”, the CPU 180 outputs a command to the pattern generator 198 to generate a test pattern for adjusting the position of the light modulation element 20. Then, the pattern generation unit 198 outputs a test pattern to the image processing unit 196, and the image processing unit 196 outputs a video signal of the test pattern to the optical element drive unit 10. The optical element drive unit 10 to which the video signal is input outputs a control signal for controlling the light modulation element 20 to the light modulation element 20. Then, the light modulation element 20 converts the light incident from the illumination optical system 11 into the image light of the test pattern and emits it to the imaging optical system 24, and the image light extraction means 50 extracts a part of the image light. Then, the image light of the test pattern is imaged on the light detection means 58 by the imaging unit 56.

  In the next S104 “Compare test pattern with image data acquired from light detection means”, CPU 180 obtains default image data of the test pattern obtained when light modulation element 20 is attached at a normal position in ROM 183. Are compared with the image data of the test pattern actually formed on the light detection means 58.

  In the next step S106 “Acquire difference between test pattern and image data acquired from light detection means”, CPU 180 determines the difference between the default image data of the test pattern and the image data of the test pattern acquired from light detection means 58. To get. Then, the process proceeds to the next step S108 “Adjustment required?”.

  In S108, the CPU 180 determines whether or not the difference in brightness value between the default image data and the image data of the test pattern imaged on the light detection means 58 exceeds a predetermined allowable range. Is going. If the difference between the default image data and the image data of the test pattern imaged on the light detection means 58 is within a predetermined allowable range, it is not necessary to adjust the position of the light modulation element 20. And the routine of the position adjustment process is terminated.

  On the other hand, when the difference between the default image data and the image data of the test pattern imaged on the light detection means 58 exceeds a predetermined allowable range, the position of the light modulation element 20 needs to be adjusted. Branching to S110 “tilt?” Processing.

  In S110, the CPU 180 determines whether or not the inclination of the light modulation element 20 needs to be adjusted. If it is determined that there is no trapezoidal distortion in the image data of the test pattern imaged on the light detection means 58, the process proceeds to the next determination of S114 “Parallel direction?”. If it is determined that trapezoidal distortion exists in the image data of the test pattern imaged on the light detection means 58, the process branches to S112 “tilt adjustment”.

  In S112, the CPU 180 calculates the degree of trapezoidal distortion of the image data of the test pattern imaged on the light detection means 58, and calculates the normal between the light modulation element 20 and the optical axis of the imaging optical system 24. A command for adjusting the angle is output to the position adjusting means 80 via the position control means 197. In this way, the adjustment that reduces the trapezoidal distortion of the image projected by the projection device 110 can be automatically performed.

  In the next S114, the CPU 180 determines whether or not the position in the direction parallel to the surface of the light modulation element 20 needs to be adjusted. For example, if it is determined that there is no position shift in the image data of the test pattern imaged on the light detection means 58, the process proceeds to the next determination of S118 "Vertical direction?" If it is determined that there is a position shift in the image data of the test pattern imaged on 58, the process branches to S116 "parallel direction adjustment".

  In S116, the CPU 180 calculates the amount of positional deviation between the default image data and the image data of the test pattern imaged on the light detection means 58 using the position of the center of gravity of the image data of the test pattern. A command for adjusting the position in the direction parallel to the surface of the light modulation element 20 is output to the position adjusting means 80 via the position control means 197. In this way, it is possible to automatically perform adjustment to reduce the positional deviation of the image projected by the projection device 110.

  In next S 118, the CPU 180 determines whether or not it is necessary to adjust the position in the direction perpendicular to the surface of the light modulation element 20. For example, if it is determined that the difference between the size of the test pattern image formed on the light detection means 58 and the default image size is within the allowable range, the position adjustment processing routine is terminated. To do. On the other hand, if it is determined that the difference between the size of the test pattern image formed on the light detection means 58 and the size of the default image exceeds the allowable range, S120 “vertical direction” Branches to the process of “adjustment”.

  In S120, the CPU 180 gives a command for adjusting the position in the direction perpendicular to the surface of the light modulation element 20 in accordance with the difference between the size of the test pattern image and the default image size. It outputs to the position adjusting means 80 via 197. In this way, it is possible to automatically perform adjustment to reduce the positional deviation of the image projected by the projection device 110.

  For example, as shown in FIG. 17, when the light modulation element image 59B formed on the light detection means 58 is larger than the default light modulation element image 59D, the size of the default light modulation element image 59D. Using this degree, a command to move the light modulation element 20 backward is output to the position adjusting means 80 to adjust the position of the light modulation element 20 in the Z direction. Then, the light modulation element image 59B is adjusted to be equal to the default light modulation element image 59D.

  On the other hand, as shown in FIG. 19, when the light modulation element image 59C formed on the light detection means 58 is smaller than the default light modulation element image 59D, it is larger than the default light modulation element image 59D. Using the degree, the command for moving the light modulation element 20 forward is output to the position adjustment means 80, and the position of the light modulation element 20 in the Z direction is adjusted. Then, the light modulation element image 59C is adjusted to be equal to the default light modulation element image 59D. In this way, the size of the image projected by the projection device 110 can be automatically adjusted.

It is a block diagram which shows the internal structure of the projection apparatus of embodiment of the image | video production | generation apparatus which concerns on this invention. 2 is a block diagram of a signal processing system of the projection apparatus 10. FIG. It is a figure which shows embodiment of the operation part of the input means. It is a figure which shows other embodiment of the light detection means 58 in the projection apparatus 110 of embodiment which concerns on this invention. It is a figure which shows embodiment of the test pattern of light quantity distribution that the brightness | luminance of center vicinity becomes high. It is a figure which shows deviation | shift between default image data and the image data obtained from the light quantity detection means. It is a figure which shows embodiment of the test pattern which provided the marker in four corners. It is a figure which shows the image data distorted to the trapezoid obtained from the light quantity detection means. It is a figure which shows embodiment of the projection apparatus which used the small extraction mirror for the image light extraction means. It is a top view which shows other embodiment of the position adjustment means 80 of this invention. FIG. 11 is a cross-sectional view of the position adjusting unit 80, the light modulation element 20, and the mounting base 70 shown in FIG. FIG. 6 is a side view of the extraction imaging optical system 54 when the light modulation element 20 exists at a default position D. 7 is a diagram showing a light modulation element image 59 formed on the light detection means 58 when the light modulation element 20 is present at a default position D. FIG. FIG. 6 is a side view of the extraction imaging optical system 54 when the light modulation element 20 is inclined by an angle θ with respect to a default position D. 6 is a diagram showing the shape of a light modulation element image 59A formed on the light detection means 58 when the light modulation element 20 is inclined by an angle θ with respect to a default position D. FIG. FIG. 6 is a side view of the extraction imaging optical system 54 when the light modulation element 20 exists ahead of the default position D by a distance of ΔZ. FIG. 10 is a diagram showing the shape of a light modulation element image 59B formed on the light detection means 58 when the light modulation element 20 exists ahead of the default position D by a distance of ΔZ. FIG. 6 is a side view of the extraction imaging optical system 54 when the light modulation element 20 exists behind the default position D by a distance of ΔZ. FIG. 10 is a diagram showing the shape of a light modulation element image 59C formed on the light detection means 58 when the light modulation element 20 exists behind the default position D by a distance of ΔZ. FIG. 6 is a side view of the extraction imaging optical system 54 when the light modulation element 20 is shifted from the default position D by a distance of ΔX. FIG. 10 is a diagram showing the shape of a light modulation element image 59E formed on the light detection means 58 when the light modulation element 20 is shifted from the default position D by a distance of ΔX and ΔY. It is a flowchart of the position adjustment process of the light modulation element using the projector which concerns on embodiment of this invention.

Explanation of symbols

10, 110, 210 Projector 11 Illumination optical system 12 Light source 13 Reflector 14 Condenser lens 16 Color wheel 18 Light tunnel 20 Light modulation element 22 Prism 24 Imaging optical system 26 Screen 34 Cross button 36 for angle adjustment For adjusting parallel position Cross button 38 Cursor button 40 for adjusting the in-focus position First relay lens 42 Aperture 44 Reflecting mirror 46 Second relay lens 50 Image light extraction means 52 Extraction mirror 54 Extraction imaging optical system 56 Imaging unit 58 Light detection means 59 Light modulation element image 60 Expansion / contraction means 62 Elastic body 64 Angle adjustment means 70 Mounting base 72 Coil 74 Magnet 76 Carriage 78, 79 Position adjustment means 80 Position adjustment means 82 Casing 151 Control part 170 Input means 172 Display part 180 CPU
181 RAM
183 ROM
195 Lamp control circuit 196 Image processing unit 197 Position control means 199 Bus

Claims (12)

A projection apparatus comprising: an illumination optical system that irradiates light; a light modulation element that converts light emitted from the illumination optical system into image light; and an imaging optical system that projects the image light,
Position adjusting means for adjusting the position of the light modulation element;
Image light extraction means for extracting a part of the image light emitted from the light modulation element;
An imaging unit for imaging the extracted image light;
A light detecting means for detecting the imaged light modulation element image;
A projection apparatus comprising: The light detection means is a photoelectric conversion element that converts an image formed into an electrical signal,
Position control means for outputting a command for controlling the position of the light modulation element to the position adjustment means using the electrical signal;
A projection apparatus according to claim 1.   3. The position control unit according to claim 2, wherein the position control unit acquires an entire image of the light modulation element formed on the photoelectric conversion element, detects a deviation from a default position, and outputs the command to the position adjustment unit. Projection device. A pattern generator for generating a test pattern for adjusting the position of the light modulation element;
An image processing unit that inputs the test pattern and outputs a control signal for causing the light modulation element to generate video light of the test pattern;
The projection apparatus according to claim 2, wherein the position control unit outputs the command to the position adjustment unit using an image of a test pattern imaged on the photoelectric conversion element.   5. The position adjusting unit includes an angle adjusting unit that adjusts an angle between a normal line of the light modulation element and an optical axis of the imaging optical system by tilting the light modulation element. The projection device according to any one of the above.   The position adjustment means includes position adjustment means for adjusting the position of the imaging optical system with respect to the optical axis by moving the light modulation element parallel or perpendicular to the surface of the light modulation element. 6. The projection device according to any one of 5 above.   The projection apparatus according to claim 1, wherein a piezoelectric element is used as an actuator of the position adjusting unit.   The projection apparatus according to claim 1, wherein a linear motor is used as an actuator of the position adjusting unit. The imaging optical system is a lens group including a first relay lens arranged on the light modulation element side and a second relay lens arranged on the side emitting the projected image,
The said image light extraction means extracts a part of image light which the said light modulation element produced | generated from between the said 1st relay lens and the said 2nd relay lens. The projection apparatus described in 1. The imaging optical system includes a first relay lens disposed on the light modulation element side, a diaphragm disposed at a subsequent stage of the first relay lens to adjust a light amount, and a projection image subsequent to the diaphragm. And a second relay lens disposed on the side from which light is emitted,
The projection according to any one of claims 1 to 8, wherein the image light extraction unit extracts a part of the image light generated by the light modulation element from between the diaphragm and the second relay lens. apparatus. The imaging optical system includes a relay lens 1 disposed on the light modulation element side, a diaphragm disposed at the rear stage of the relay lens 1 to adjust the amount of light, and a light irradiation direction disposed at the rear stage of the diaphragm. And a second relay lens disposed on the side of emitting the projection image at a later stage than the reflecting mirror, and a lens group including:
The projection apparatus according to claim 1, wherein the image light extraction unit extracts a part of the image light generated by the light modulation element from a part of the reflecting mirror.   The projection apparatus according to claim 1, wherein a screen mat that displays an image is used as the light detection unit.

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