JP2011082798A - Projection graphic display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection graphic display device capable of displaying a projection video conformed to the shape of a screen by a simple configuration. <P>SOLUTION: A projector 10 includes: a light source 30; a video-signal processor 60 generating a video signal for the projection video by converting an input video signal; and an indicating element 40 generating a video light by modulating outgoing light from the light source 30 on the basis of the video signal generated by the video-signal processor 60. The projector further includes a projection optical system 50 projecting the video light generated by the indicating element 40 to a projection surface 100. The screen 120 is mounted on the projection surface 100. The video signal processor 60 includes: a mask-information generating means generating mask information for masking the video light in response to a non-display area on the basis of display-region information indicating the region of the screen 120; and a mask-video generating means converting the non-display area into a mask video signal for displaying a black on the basis of the mask information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a projection display apparatus, and more particularly to a technique for displaying a projection image that matches the shape of a screen in the projection display apparatus.

  In recent years, with the advancement of digital technology, a system called digital signage, which performs advertisement by reproducing high-quality images such as high-definition image quality on a display in stores or outdoors, has become widespread.

  In this digital signage system, as disclosed in, for example, JP-T-2004-533636 (Patent Document 1), a video signal supplied from an external video supply device such as a PC (personal computer) or a video playback device is received. A form of displaying on a projection display apparatus (hereinafter also referred to as a projector) installed in a store or outdoors is widely adopted. According to this, since the customer who visited the store can browse advertisements using video and audio, the advertising effect is considered to be much larger than conventional paper media posters. In recent years, it is spreading rapidly.

  As a specific form of use of the projector, an image is projected on a projection surface obtained by cutting and pasting a film-like screen into a specific shape on a shop window, or an image is projected onto a screen cut into a person's shape. The advertisement effect is further enhanced with respect to the normal usage pattern in which the image is projected onto a rectangular screen.

  In such a usage mode, when displaying a video on the projector, video content matching the shape of the screen is created in advance, and the projector is adjusted so that the video fits within the frame of the screen.

JP-T-2004-533636

  However, in the above-described usage mode, troublesome installation adjustment of the projector occurs, and it is necessary to produce video content that matches the screen shape in advance.

  In particular, when the video content does not match the shape of the screen, the area of the image projected by the projector may protrude from the screen area on the projection surface, and thus may be directly incident on the observer's eyes. is there. Therefore, it is indispensable to perform installation adjustment accurately.

  Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to provide a projection-type image display device capable of displaying a projection image that matches the shape of the screen with a simple configuration. Is to provide.

  A projection display apparatus according to an aspect of the present invention includes a light source, a video signal processing unit that converts an input video signal to generate a video signal for projection video, and a video signal generated by the video signal processing unit. And a projection element that modulates the light emitted from the light source to generate image light and a projection optical system that projects the image light generated by the display element onto the projection surface. The projection plane has a non-display area that does not display an image and a display area that displays an image. The image signal processing unit generates display area information input means for inputting display area information indicating the display area on the projection plane, and mask information for masking image light corresponding to the non-display area based on the display area information. And a mask video generation unit that converts the input video signal into a mask video signal for displaying a non-display area in black based on the mask information.

  Preferably, the video signal processing unit switches between a mask mode in which the mask video signal generated by the mask video generation means is supplied to the display element and a normal mode in which the input video signal is supplied to the display element as it is. Further includes mode switching means for operating the.

  Preferably, the display area input unit includes an imaging unit that captures a projected image when the test pattern is projected onto the projection plane and generates a captured image. The mask information generation unit compares a difference value between a plurality of captured images generated by the imaging unit when a plurality of test patterns having different brightness are projected on the projection surface, and a predetermined threshold value. Based on this, mask information is generated. The predetermined threshold is configured to be changeable according to the environment where the projection plane is installed.

  Preferably, the projection display apparatus further includes image adjusting means for shifting the display position of the image projected on the projection surface or changing the display size. The mask information generating means finely adjusts the generated mask information based on the image adjustment amount specified by the image adjusting means when image light based on the mask video signal is projected onto the projection surface. Including adjustment means.

  Preferably, the display area input unit includes an imaging unit that captures a projected image when the test pattern is projected onto the projection plane and generates a captured image. The video signal processing unit includes a first test pattern in which the entire screen is displayed in a single color and a second test in which the screen is divided into a plurality of pixel blocks and the brightness is changed from the first test pattern in pixel block units. Test pattern generation means for generating a pattern is further included. The mask information generating means uses the imaging means when the first test image generated by the imaging means when the first test pattern is projected onto the projection plane and the second test pattern is projected onto the projection plane. Based on the difference value from the generated second captured image, mask information is generated in units of pixel blocks.

  Preferably, the display area input unit includes an imaging unit that captures a projected image when the test pattern is projected onto the projection plane and generates a captured image. The video signal processing unit further includes test pattern generation means for generating a test pattern having a first area and a second area, which are alternately arranged along a predetermined direction of the display screen and have different brightness. The test pattern generation means generates a plurality of test patterns by varying the number of first and second regions arranged on the display screen, and displays the display screen based on the generated plurality of test patterns. The position of each pixel in a predetermined direction is specified. The mask information generating means generates mask information based on the difference values of the plurality of captured images generated by the imaging means when a plurality of test patterns are projected on the projection plane and the positions of the pixels in a predetermined direction. To do.

  According to the present invention, it is possible to display a projected image that matches the shape of the screen with a simple configuration.

It is a figure which shows the state at the time of the image projection of the projection type video display apparatus concerning Embodiment 1 of this invention. It is a figure which shows the state seen from the A direction of FIG. 1 is an overall configuration diagram of a projector according to a first embodiment. 6 is a flowchart illustrating a video signal processing routine executed by a video signal processing unit in the projector according to the first embodiment. It is a figure explaining the picked-up image which imaged the projection image | video based on a test pattern. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on the example 1 of a change of this Embodiment 1 performs. It is a figure which shows a projection image when the all white test pattern converted based on mask information is projected. It is a figure explaining the structure of the video signal process part in the projector which concerns on the modification 2 of this Embodiment 1. FIG. It is a figure explaining the structure of the video signal processing part in the projector which concerns on the modification 3 of this Embodiment 1. FIG. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on the modification 4 of this Embodiment 1 performs. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on the modification 5 of this Embodiment 1 performs. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on this Embodiment 2 performs. It is a figure explaining the procedure which changes a test pattern. It is a figure explaining the picked-up image acquired by a camera whenever a test pattern is changed. It is a figure explaining a position information table. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on this Embodiment 3 performs. It is a figure explaining the procedure which changes a test pattern. It is a figure explaining a position information table. It is a figure which shows the state at the time of the image projection of the projector which concerns on Embodiment 4 of this invention. It is a figure which shows the state seen from the B direction of FIG. It is a flowchart explaining the video signal processing routine which the video signal processing part in the projector which concerns on this Embodiment 4 performs. It is a figure which shows the display area (operation area of a touch panel) of a monitor. It is a figure explaining the synthesized image projected on a projection surface. It is a figure explaining the procedure which corrects a drawing image. It is a figure which shows the state at the time of the image projection of the projector which concerns on Embodiment 5 of this invention. It is a figure which shows the state seen from the B direction of FIG. It is a flowchart explaining the video signal processing routine which the video signal process part in the projector which concerns on this Embodiment 5 performs.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a diagram showing a state at the time of image projection of the projection display apparatus according to Embodiment 1 of the present invention. FIG. 2 is a diagram showing a state viewed from the direction A in FIG.

  Referring to FIG. 1, a projection display apparatus (hereinafter also referred to as “projector”) 10 according to the first embodiment is a liquid crystal projector that projects an image using a liquid crystal device, and has a projection surface. A projected image 110 is displayed by projecting light of an image displayed on the liquid crystal device 100.

  The projection surface 100 is made of a transparent body made of glass or the like, and transmits image light from the projector 10. A screen 120 is installed on the projection surface 100. The screen 120 can be switched between a transparent state and a diffusion state by applying a voltage, and is a film-like one that switches to the diffusion state when the image light from the projector 10 is irradiated and displays the light. It is. For example, if the film-like screen 120 is directly attached to a store window or the like, when light is not irradiated from the projector 10, the transparent state is maintained integrally with the window by switching to the transparent state. . And when light is irradiated from the projector 10, since it can display an image | video by switching to a diffusion state, it can be utilized as a screen, without losing the function of a window.

  Note that the screen 120 is not limited to a film that can be switched between the transparent state and the diffusion state as described above, and may be one using a diffusion material that does not change in state. However, as shown in FIG. 2, when the screen 120 is irradiated with light, it is necessary to be able to recognize the information of the projected image from the side opposite to the projector 10 (from the direction A in the figure).

  Thereby, the projection plane 100 is divided into a non-display area that does not display an image and a display area that displays an image. The display area corresponds to the screen 120. The non-display area corresponds to an area obtained by removing the screen 120 from the display area of the projected image 110.

  The projector 10 includes a camera 20 that captures an area including the projected image 110 via an imaging surface and generates a captured image. The camera 20 includes an image sensor, an image sensor control unit that controls the image sensor such as acquisition of an output signal from each pixel of the image sensor, and an imaging optical system. For example, a CCD or CMOS can be used as the image sensor.

(Projector configuration)
FIG. 3 is an overall configuration diagram of the projector 10 according to the first embodiment.

  Referring to FIG. 3, projector 10 includes camera 20, light source 30, display element 40 that modulates light emitted from light source 30 to generate image light, and image light generated by display element 40. A projection optical system 50 that projects onto the projection surface 100 and a video signal processing unit 60 that converts an input video signal and generates a video signal for a projected video are provided.

  The light source 30 is a discharge-type light source lamp such as an ultrahigh pressure mercury lamp or a metal halide lamp. Furthermore, the present invention is not limited to a discharge light source lamp, and various solid light emitting elements such as an LED, a laser diode, an organic EL (Electro Luminescence) element, and a silicon light emitting element may be employed.

  The display element 40 includes a liquid crystal light valve configured by a liquid crystal panel or the like in which liquid crystal is sealed between a pair of transparent substrates. In the liquid crystal light valve, a rectangular pixel region composed of a plurality of pixels arranged on a matrix is formed, and a driving voltage can be applied to the liquid crystal for each pixel. When a driving voltage corresponding to a video signal is applied to each pixel of the liquid crystal light valve by driving a light valve driving unit (not shown), the light emitted from the light source 30 is different from the liquid crystal light valve with a different light transmittance for each pixel. , And becomes image light corresponding to the image signal, and is projected onto the projection plane 100 by the projection optical system 50.

  Although not shown, the display element 40 includes three liquid crystal light valves for light of the three primary colors, red (R), green (G), and blue (B). The light emitted from the light source 30 is separated into three color lights by a light separation optical system (not shown), and then enters a liquid crystal light valve for each color light. The image light of each color transmitted through the liquid crystal light valve is color-combined for each pixel by a light combining optical system (not shown), and is projected from the projection optical system 50 as image light indicating a color image.

  The video signal processing unit 60 samples a video signal input from an external video supply device (not shown) such as a PC (personal computer) or a video playback device, and generates digital video data corresponding to the video signal. To do. Further, the video signal processing unit 60 performs various data processing (video signal processing) on the generated video data, and outputs the processed video data to the display element 40.

  Here, the projector 10 according to the first embodiment has an “initialization mode” for initial setting of the projector 10 when the power is turned on or a projection instruction, and a non-display area (see FIG. 2) and masking a part of the image light and projecting it on the projection surface 100, and the image surface corresponding to the input image signal as it is (that is, without masking) the projection surface. 100 has a “normal mode” for projecting to 100. Switching between these three modes is executed in accordance with an operation signal issued from an input operation unit for giving various instructions to projector 10 in accordance with a user operation. The input operation unit is configured by using a plurality of keys provided on the main body of the projector 10 or a remote control that can be operated remotely (abbreviation of a remote controller).

  When one of the three operation modes is selected in accordance with a user operation, the video signal processing unit 60 performs image processing defined in advance in the selected operation mode on the video data, The subsequent video data is output to the display element 40.

  First, in the initialization mode executed when the power is turned on, the video signal processing unit 60 causes a plurality of test patterns having different brightness to be projected onto the projection plane 100 in succession. At this time, a plurality of projected images 110 displayed on the projection plane 100 are captured by the camera 20. The video signal processing unit 60 compares a plurality of captured images acquired by the camera 20 by a method to be described later, so that an area of the screen 120 that is a display area of the projected video 110 (hereinafter also referred to as a screen area). To detect. Then, the video signal processing unit 60 generates mask information for masking the video light in correspondence with the non-display area other than the screen 120 based on the detected screen area.

  Next, when the mask mode is selected as the operation mode in accordance with the user operation, the video signal processing unit 60 displays a video signal as a mask for displaying the non-display area in black based on the mask information generated in the initialization mode. Convert to video signal. Thus, in the mask mode, an image is displayed on the screen 120 with respect to the projection image 110, while an area other than the screen 120 is projected on the projection plane 100 as a black display. As a result, the intensity of the light transmitted through the non-display area is suppressed, so that it is possible to prevent light from being directly incident on the eyes of the observer on the opposite side of the projection plane 100. Further, the image projected on the screen 120 can be easily viewed by the observer.

  On the other hand, when the projection surface 100 is not a transparent body (for example, a wall surface), the normal mode is selected according to the user's operation. In this case, the video signal processing unit 60 outputs the input video signal to the display element 40 as it is without converting the input video signal into the mask video signal described above. As a result, the entire area of the projected image 110 is displayed on the projection plane 100.

(Configuration of video signal processor)
The video signal processing unit 60 has an image storage unit 70, a difference detection unit 72, a threshold control unit 74, a mask information generation unit 76, and a mask information storage as a configuration for realizing such three operation modes. Unit 78, mask video generation unit 80, test pattern generation unit 82, video signal selection unit 84, mode switching unit 86, and control unit 90.

  The control unit 90 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) including a flash memory, a RAM (Random Access Memory) used for temporary storage of various data, etc. (none of which are shown), It functions as a computer. The control unit 90 performs overall control of the operation of the projector 10 by the CPU operating according to a control program stored in the ROM.

  As described above, the camera 20 captures an area including the projected image 110 via the imaging surface to generate a captured image. As will be described later, the image storage unit 70 temporarily captures a captured image acquired by the camera 20 when the test pattern generated by the test pattern generation unit 82 is projected onto the projection plane 100 during execution of the initialization mode. Remember me.

  The difference detection unit 72 detects a difference value between a plurality of captured images when a plurality of test patterns having different brightness are projected on the projection plane 100. The difference detection unit 72 compares the detected difference value with a predetermined threshold given from the threshold control unit 74 and outputs the comparison result to the mask information generation unit 76.

  The mask information generation unit 76 generates mask information based on a comparison result between the difference values of the plurality of captured images detected by the difference detection unit 72 and a predetermined threshold value. The generated mask information is stored in the mask information storage unit 78.

  The mask video generation unit 80 refers to the mask information stored in the mask information storage unit 78 during execution of the mask mode so that the input video signal is displayed in black in a region other than the screen (non-display region). To the mask video signal.

  The video signal selection unit 84 receives a test pattern from the test pattern generation unit 82, receives a mask video signal from the mask video generation unit 80, and receives an input video signal from an external video supply device. Then, the video signal selection unit 84 selects any one of the test pattern, the mask video signal, and the input video signal according to the mode switching signal from the mode switching unit 86 and outputs it to the display element 40.

  Specifically, mode switching unit 86 switches the operation mode of projector 10 based on an operation signal issued from an input operation unit (not shown). For example, when the power is turned on, the mode switching unit 86 switches the operation mode so as to select the initialization mode. The mode switching unit 86 transmits a signal indicating the operation mode after switching (mode switching signal) to the control unit 90 and the video signal selection unit 84.

  The video signal selection unit 84 selects a test pattern and outputs it to the display element 40 in accordance with the switching to the initialization mode. Further, the video signal selection unit 84 selects a mask video signal and outputs it to the display element 40 in accordance with the switching to the mask mode. Further, the video signal selection unit 84 selects a video signal and outputs it to the display element 40 in accordance with the switching to the normal mode.

(Video signal processing)
Next, the video signal processing in the video signal processing unit 60 according to the first embodiment will be described in more detail.

  FIG. 4 is a flowchart for explaining a video signal processing routine executed by the video signal processing unit 60. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 4, first, control unit 90 determines whether or not the current operation mode is an initialization mode in step S01.

  When the current operation mode is the initialization mode (when YES is determined in S01), the test pattern generation unit 82 is also referred to as a test pattern (hereinafter, referred to as “all black test pattern”) that displays the entire screen in a single black color. ) Is generated. The video signal selection unit 84 outputs the generated all black test pattern to the display element 40 in response to the mode switching signal. As a result, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-black test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S02). In step S03, the projected image 110 based on the all black test pattern is captured by the camera 20. The image storage unit 70 stores the captured image acquired by the camera 20 as “image A”.

  Next, in step S04, the test pattern generation unit 82 generates a test pattern (hereinafter, also referred to as “all white test pattern”) that displays the entire screen in a single color of white. The video signal selection unit 84 outputs the generated all white test pattern to the display element 40. Thereby, in the display element, the light emitted from the light source 30 becomes image light corresponding to the all white test pattern and is projected onto the projection plane 100 by the projection optical system 50 (step S04). In step S05, the projection image 110 based on the all white test pattern is captured by the camera 20. The image storage unit 70 stores the captured image as “image B”.

  Next, the difference detection unit 72 detects the difference between the image A and the image B by comparing the image A (full black display) and the image B (full white display) stored in the image storage unit 70. . FIG. 5 shows a result of detecting a difference for each pixel between the image A (see FIG. 5A) and the image B (see FIG. 5B) and the image A and the image B (FIG. 5 ( c)).

  Referring to FIG. 5, in image A, the screen area is displayed in black, and light is transmitted through areas other than the screen area (non-display area), so that the background image of projection plane 100 is displayed. . In the image B, the screen area is displayed in white, and the background image of the projection surface 100 is displayed in an area other than the screen area (non-display area). Therefore, when the image A and the image B are compared, the difference value in the non-display area becomes substantially zero, while a luminance difference occurs in the screen area.

  The difference detection unit 72 determines whether or not the difference value is equal to or greater than a predetermined threshold value for each pixel, and generates difference information between the image A and the image B based on the determination result. Specifically, the difference detection unit 72 generates difference information binarized by the size of the difference value for each pixel. For example, the difference detection unit 72 sets a pixel having a difference value smaller than a predetermined threshold to “0”, and sets a pixel having a difference value equal to or larger than the predetermined threshold to “1”.

  Next, the mask information generation unit 76 generates mask information based on the difference information generated by the difference detection unit 72. Specifically, the mask information generation unit 76 generates binarized mask information corresponding to the binarized difference information. As a result, the binarized mask information is generated with the pixel located in the screen area as “1” and the pixel located outside the screen area as “0”. When the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78, the initialization mode ends (step S08), and the process returns to the beginning.

  Returning again to step S01, when the current operation mode is not the initialization mode (when NO is determined in S01), control unit 90 further determines whether or not the current operation mode is the mask mode in step S09. . When the current operation mode is the mask mode (YES in S09), the mask video generation unit 80 refers to the mask information stored in the mask information storage unit 78 (step S11), and the input video signal is obtained. Conversion into a mask video signal (step S12).

  Specifically, the mask video generation unit 80 converts the input video signal into a mask video signal by taking the logical product of the input video signal and the mask information for each corresponding pixel. For example, when the mask information of the corresponding pixel is “1”, the mask video generation unit 80 sets the signal value of the input video signal as the signal value of the mask video signal, and the mask information of the corresponding pixel is “0”. Sometimes, the mask video signal is generated with the signal value of the mask video signal set to “0”. That is, for each pixel whose mask information is “0”, that is, each pixel located outside the screen area, the signal value is forcibly converted to “0” in the mask video signal. Therefore, in the projected image 110, each pixel located outside the screen area is displayed in black.

  The video signal selection unit 84 outputs the mask video signal generated by the mask video generation unit 80 to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the mask image signal, and is projected onto the projection plane 100 by the projection optical system 50 (step S12).

  On the other hand, when the current operation mode is not the mask mode (NO determination at S09), the video signal selection unit 84 outputs the input video signal to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the input image signal, and is projected onto the projection plane 100 by the projection optical system 50 (step S12).

  In step S13, the controller 90 determines whether or not the power is turned off. When the power is turned off (YES in S13), the series of video signal processing ends. On the other hand, when the power is not turned off (NO determination in S13), the process is returned to the beginning.

  As described above, according to the first embodiment of the present invention, in the initialization mode, the screen area of the projection surface is detected based on the captured image acquired by the camera that captures the projected image, and the detected screen area is detected. Mask information is generated based on the screen area. As a result, in the mask mode, a projected image in which the area other than the screen area is displayed in black based on the mask information is displayed on the projection surface. Accordingly, it is possible to easily project an image that matches the shape of the screen without the need to produce video content that completely matches the shape of the screen.

  In addition, by applying mask processing to the input video signal, the intensity of light transmitted through the non-display area other than the screen area can be suppressed, so that light is directly incident on the eyes of the observer on the opposite side of the projection plane. Can be prevented. Furthermore, the image projected on the screen can be easily viewed by the observer.

(Modification example to improve the accuracy of mask information)
Hereinafter, as a modification example of the projector according to the first embodiment, a technique for further improving the accuracy of the mask information generated in the initialization mode will be described. Note that all the projectors according to the following modification examples 1 to 5 are obtained by changing the contents of the video signal processing in the projector according to the first embodiment, and the overall configuration of the projectors is common to each other.

[Modification 1: Introduction of variable threshold]
FIG. 6 is a flowchart for explaining a video signal processing routine executed by the video signal processing unit 60 in the projector according to the first modification of the first embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 6, the flowchart according to the first modification is different only in that steps S06 and S07 in the flowchart of FIG. 4 are changed to steps S21 to S26.

  When image A (full black display) and image B (full white display) are stored in image storage unit 70 in steps S03 and S05, threshold control unit 74 (FIG. 3) sets a predetermined initial value for the threshold. (Step S21). The difference detection unit 72 detects the difference between the image A and the image B using the set threshold value (initial value) (step S22). Specifically, the difference detection unit 72 determines whether the difference value is equal to or greater than the initial value for each pixel, and generates binarized difference information based on the determination result. The difference detection unit 72 generates difference information binarized by setting a pixel having a difference value smaller than the initial value to “0” and a pixel having a difference value equal to or larger than the initial value to “1”.

  The mask information generation unit 76 generates binarized mask information corresponding to the difference information generated by the difference detection unit 72. (Step S23).

  Next, in step S24, the all white test pattern is again projected on the projection plane 100. At this time, based on the mask information generated by the mask information generation unit 76, the mask video generation unit 80 converts a partial region of the all white test pattern into a test pattern for displaying black. Specifically, the mask video generation unit 80 calculates the signal value of each pixel in which the mask information is “0” by taking the logical product of the all white test pattern and the mask information for each corresponding pixel. Forced conversion to “0”.

  FIG. 7A shows a projected image 110 when the all white test pattern converted based on the mask information in step S24 of FIG. 6 is projected. In the projected image 110, the screen area is displayed in white, while the area other than the screen area is displayed in black.

  Here, when there is an object that reflects or diffuses light in the background of the projection plane 100, the captured image acquired by the camera 20 may include an edge portion other than the screen region. This edge portion is a portion where the difference in gradation value between adjacent pixels is large, for example, appears in the contour portion of the object. As a result, when the image A and the image B are compared with each other, the difference value in the edge portion indicates a threshold value or more, so that the edge portion may be erroneously recognized as a screen region. As a result, there arises a problem that mask information that accurately reflects the shape of the screen cannot be generated.

  Therefore, the projector according to the first modification is configured such that the threshold value used for detecting the difference between the captured images in the video signal processing can be changed according to the environment where the screen 120 is installed.

  Specifically, in step S25 of FIG. 6, the projected image 110 when the all white test pattern is projected in step S24 is viewed, and it is confirmed whether there is any white display area other than the screen area. When it is confirmed that there is no white display area other than the screen area (YES in S25), the threshold value is not changed. Therefore, the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78 (step S26), and the initialization mode ends (step 08).

  On the other hand, when it is confirmed that there is a white display area other than the screen area by looking at the projected image 110 when the all white test pattern is projected (NO in S25), the process returns to step S21. The threshold value is changed. Note that the threshold value is changed by the threshold value control unit 74 changing the threshold value by an amount corresponding to an operation signal issued from the input operation unit in accordance with an instruction from the control unit 90. Thereby, after step S22, mask information is generated again using the changed threshold value. In this way, the processes in steps S21 to S24 are repeatedly executed until it is confirmed in step S25 that there is no white display area other than the screen area.

  As described above, in the video signal processing according to the first modification, the threshold value used for the difference detection of the captured image can be changed according to the environment where the screen 120 is installed. The accuracy of the mask information generated based on this can be improved.

  Note that although step S24 in FIG. 6 is configured to project an all-white test pattern in which the area other than the screen area is displayed in black, only the outline area of the screen area is displayed in white and the area other than the outline area is displayed in black. It is also possible to project the all-white test pattern converted as follows. In this case, as shown in FIG. 7B, when the white display of the contour portion is not properly displayed in the screen area, the threshold value is changed, and mask information is generated again using the changed threshold value. .

[Modification 2: Consistency of the number of pixels between the display element and the imaging element of the camera]
FIG. 8 is a diagram illustrating the configuration of the video signal processing unit in the projector according to the second modification of the first embodiment.

  Referring to FIG. 8, in the second modification, the mask information generation unit 76 in the video signal processing unit 60 (FIG. 3) is configured to include a mask information generation circuit 760 and a pixel number conversion unit 762. Note that each component (not shown) other than the mask information generation unit 76 is the same as the component included in the video signal processing unit 60 of FIG.

  The mask information generation circuit 760 generates mask information based on a comparison result between a difference value between a plurality of captured images detected by the difference detection unit 72 and a predetermined threshold value by the method described above. The generated mask information is output to the pixel number conversion unit 762.

  When the number of pixels of the imaging element of the camera 20 and the number of pixels of the display element 40 of the projector 10 do not match, the pixel number conversion unit 762 has, for example, a smaller number of pixels of the imaging element than the number of pixels of the display element 40. In this case, interpolation processing is performed on the mask information generated by the mask information generation circuit 760. Specifically, even if a signal value corresponding to one pixel of the display element 40 does not exist in the mask information, the pixel is subjected to interpolation processing using signal values corresponding to surrounding pixels surrounding the pixel. Are obtained.

  With such a configuration, the mask information can be matched with the non-display area of the projection surface with higher accuracy. As a result, in the projected image, the contour portion of the screen region can be displayed more accurately, so that direct light can be prevented from being incident on the eyes of the observer on the opposite side of the projection plane 100, and the screen The image projected on 120 can be easily viewed by the observer.

[Modification 3: Distortion correction by camera angle of view]
In the configuration in which the camera 20 is attached to the main body of the projector 10 as shown in FIG. 1, the image sensor of the camera 20 cannot be installed at a position facing the central portion of the projected image 110 due to the device configuration. In some cases, an image sensor is installed at a position shifted from the portion. In such a case, trapezoidal distortion may occur in the captured image obtained by capturing the projected image 110.

  Therefore, in the projector according to the third modification, the trapezoidal distortion generated in the captured image is corrected based on the angle-of-view distortion information of the camera 20 acquired in advance based on the positional relationship between the projector 10 and the camera 20. Then, mask information is generated based on the corrected captured image.

  FIG. 9 is a diagram for explaining the configuration of the video signal processing unit in the projector according to the third modification of the first embodiment.

  Referring to FIG. 9, in the third modification, the mask information generation unit 76 in the video signal processing unit 60 (FIG. 3) includes a mask information generation circuit 760, a distortion correction unit 764, and an angle-of-view distortion information storage unit 766. And a pixel number conversion unit 762. Note that each component (not shown) other than the mask information generation unit 76 is the same as the component included in the video signal processing unit 60 of FIG.

  The mask information generation circuit 760 generates mask information based on a comparison result between a difference value between a plurality of captured images detected by the difference detection unit 72 and a predetermined threshold value by the method described above. The generated mask information is output to the distortion correction unit 764.

  The distortion correction unit 764 corrects the mask information generated by the mask information generation circuit 760 by referring to the view angle distortion information stored in the view angle distortion information storage unit 766. Specifically, the distortion correction unit 764 sets which pixel value of each pixel of the image sensor is to be read based on the view angle distortion information. The corrected mask information is output to the pixel number conversion unit 762.

  The pixel number conversion unit 762 interpolates the mask information generated by the mask information generation circuit 760 when the number of pixels of the imaging element of the camera 20 and the number of pixels of the display element 40 of the projector 10 do not match. Apply processing. Specifically, even if a signal value corresponding to one pixel of the display element 40 does not exist in the mask information, the pixel is subjected to interpolation processing using signal values corresponding to surrounding pixels surrounding the pixel. Are obtained.

  With such a configuration, the mask information can be made to coincide with the non-display area of the projection plane with high accuracy without being influenced by the positional relationship between the projector 10 and the camera 20.

[Modification 4: Test pattern color display]
Depending on the material color of the screen 120 and the environment in which the screen 120 is installed, the difference between the image A obtained by capturing the projected image based on the all-black test pattern and the image B obtained by capturing the projected image based on the all-white test pattern is detected. May be difficult.

  In the projector according to the fourth modification, the display color of the test pattern is switched and projected onto the projection surface. And mask information shall be produced | generated based on the difference of the some captured image acquired by the image pick-up element at this time.

  FIG. 10 is a flowchart illustrating a video signal processing routine executed by the video signal processing unit 60 in the projector according to the fourth modification of the first embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 10, the flowchart according to the fourth modification is different only in that steps S04 to S07 in the flowchart of FIG. 4 are changed to steps S31 to S41.

  When the current operation mode is the initialization mode (YES in S01), the test pattern generation unit 82 generates an all black test pattern, and the video signal selection unit 84 generates the generated all black test pattern. Is output to the display element 40. As a result, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-black test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S02). In step S03, the camera 20 captures the projected image 110 based on the all black test pattern. The image storage unit 70 stores the captured image as “image A”.

  Next, in step S31, the test pattern generation unit 82 generates an all white test pattern. The video signal selection unit 84 outputs the generated all white test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all white test pattern, and is projected onto the projection plane 100 by the projection optical system 50. In step S32, the camera 20 captures the projected image 110 based on the all white test pattern. The image storage unit 70 stores the captured image as “image W”.

  Next, in step S33, the test pattern generation unit 82 generates a test pattern (hereinafter, also referred to as “all-red test pattern”) that displays the entire screen in a single red color. The video signal selection unit 84 outputs the generated all-red test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-red test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S33). In step S34, the camera 20 captures the projected image 110 based on the all-red test pattern. The image storage unit 70 stores the captured image as “image R”.

  Next, in step S35, the test pattern generation unit 82 generates a test pattern (hereinafter, also referred to as “all green test pattern”) that displays the entire screen in a single color of green. The video signal selection unit 84 outputs the generated all green test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all green test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S35). In step S36, the camera 20 captures the projected image 110 based on the all green test pattern. The image storage unit 70 stores the captured image as “image G”.

  Next, in step S <b> 37, the test pattern generation unit 82 generates a test pattern (hereinafter, also referred to as “all-blue test pattern”) that displays the entire screen in a single blue color. The video signal selection unit 84 outputs the generated all-blue test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-blue test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S37). In step S38, the camera 20 captures the projected image 110 based on the all-blue test pattern. The image storage unit 70 stores the captured image as “image B”.

  The difference detection unit 72 includes an image A (all black display), an image W (all white display), an image R (all red display), an image G (all green display), and an image B stored in the image storage unit 70. The difference between the image A and each of the images W, R, G, and B is detected by comparing each (all blue display) (step S06). Specifically, the difference detection unit 72 determines whether or not the difference value for each pixel is greater than or equal to a predetermined threshold between the image A and the image W, and the image A and the image W are based on the determination result. Difference information is generated. Similarly, the difference detection unit 72 generates difference information between the image A and the image R, generates difference information between the image A and the image G, and generates difference information between the image A and the image B. In addition, the threshold value used for each difference detection may not be common.

  Next, the difference detection unit 72 compares the four pieces of generated difference information to detect a pixel in which the difference values match between the four pieces of difference information in the projection area of the projector 10 (step S40). . The difference detection unit 72 generates difference information including the detected pixel position information and outputs the difference information to the mask information generation unit 76.

  Based on the difference information generated by the difference detection unit 72, the mask information generation unit 76 generates mask information binarized by the magnitude of the difference value for each pixel. When the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78, the initialization mode ends (step S08), and the process returns to the beginning.

  As described above, the mask information is generated based on the plurality of captured images acquired when the test pattern is projected with the plurality of display colors, so that the screen area can be accurately detected regardless of the state of the screen 120. Therefore, the mask information can be matched with the non-display area of the projection plane with high accuracy.

[Modification 5: Fine adjustment of mask information]
In the projector according to the fifth modification, the mask information generated based on the difference information of the captured image can be finely adjusted according to the user's operation.

  FIG. 11 is a flowchart for explaining a video signal processing routine executed by the video signal processing unit 60 in the projector according to the fifth modification of the first embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 11, the flowchart according to the fifth modification is different only in that step S07 in the flowchart of FIG. 4 is changed to steps S51 to S55.

  As shown in FIG. 11, in step S <b> 06, the difference detection unit 72 detects a difference between the image A and the image B. Specifically, the difference detection unit 72 determines whether or not the difference value is equal to or greater than a threshold value for each pixel, and generates binarized difference information based on the determination result.

  The mask information generation unit 76 generates binarized mask information corresponding to the difference information generated by the difference detection unit 72. (Step S51).

  Next, in step S52, the all-white test pattern is again projected on the projection plane 100. At this time, based on the mask information generated by the mask information generation unit 76, the mask video generation unit 80 converts a partial region of the all white test pattern into a test pattern for displaying black. Specifically, the mask video generation unit 80 calculates the signal value of each pixel in which the mask information is “0” by taking the logical product of the all white test pattern and the mask information for each corresponding pixel. Forced conversion to “0”.

  In step S53, the user looks at the projected image 110 when the all white test pattern is projected in step S52, and confirms that there is no white display area other than the screen area. When it is confirmed that there is no white display area other than the screen area (YES in S53), the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78 (step S55). The initialization mode ends (step 08).

  On the other hand, when the user sees the projected image 110 when the all-white test pattern is projected and confirms that there is a white display area other than the screen area (NO determination in S53), the mask is displayed. Information adjustment is performed (step S54).

  Adjustment of the mask information is performed by the user operating an operation button provided on the input operation unit. The operation buttons include an enlargement / reduction button for enlarging / reducing the image and a shift button for shifting the image vertically and horizontally. The user sets the adjustment amount of the mask information by operating these buttons while viewing the projected image 110 when the all white test pattern is projected in step S52. The mask information generation unit 76 adjusts the mask information according to the set adjustment amount. As a result, an all-white test pattern converted so that a part of the area is displayed in black based on the adjusted mask information is projected onto the projection plane 100.

  In this way, the processes in steps S52 to S54 are repeatedly executed until it is confirmed in step S53 that there is no white display area other than the screen area. Then, the mask information with the white display area within the screen area is stored in the mask information storage unit 78 as final mask information (step S55).

  As described above, in the video signal processing according to the fifth modification, the mask information can be finely adjusted based on the projection image when the test pattern converted using the mask information is projected. The accuracy of information can be increased.

  In the fifth modification, the mask information is adjusted based on the projection image when the all white test pattern is projected. However, the zoom function and the shift function installed in the projection optical system 50 are used. Thus, it may be configured to finely adjust the projected image. In this case, the shift position and zoom position of the projection optical system 50 are adjusted so that the white display area is within the screen area.

[Modification 6]
In the first embodiment of the present invention described above and the first to fifth modifications thereof, mask information is obtained by capturing a projected image based on a plurality of test patterns having different brightness with a camera and detecting a difference between the plurality of captured images. In the situation where the screen is installed in a relatively dark environment or the projection effective area of the projector is covered with a black curtain, etc., the brightness level of the captured image is used instead of the difference detection. The mask information can be generated by adopting a configuration for detecting.

  Specifically, in the initialization mode, an all white test pattern is projected on the projection plane 100 and the projected image 110 is captured by the camera 20. The video signal processing unit 60 stores the captured image as “image A”. Then, the video signal processing unit 60 determines whether or not the luminance level is equal to or higher than a predetermined threshold value for each pixel of the image A, and generates mask information based on the determination result. As a result, binarized mask information is generated by setting a pixel whose luminance level is lower than the predetermined threshold to “0” and a pixel having a luminance level equal to or higher than the predetermined threshold to “1”.

  Further, the accuracy of the mask information can be improved by using the size information of the screen 120 to generate the mask information. More specifically, the mask information generation unit 76 has information about the size of the screen 120 in advance, and among the binarized mask information, the mask information is “1” in the area. Count the number of adjacent adjacent pixels. The mask information generation unit 76 compares the count value with a reference value set in advance based on the size information of the screen 120, and determines that the area is a noise area when the count value falls below the reference value. Rewrite the mask information to “0”.

[Embodiment 2]
FIG. 12 is a flowchart for explaining a video signal processing routine executed by the video signal processing unit 60 in the projector according to the second embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 12, the flowchart according to the second embodiment is different only in that steps S02 to S07 in the flowchart of FIG. 4 are changed to steps S61 to S68.

  As shown in FIG. 12, when the current operation mode is the initialization mode (when YES is determined in S01), the test pattern generation unit 82 generates an all white test pattern. The video signal selection unit 84 outputs the generated all white test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-white test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S61). In step S <b> 62, the projected image 110 based on the all white test pattern is captured by the camera 20. The image storage unit 70 stores the captured image as “image A”.

  Next, the test pattern generation unit 82 changes the test pattern to a test pattern in which a part of the screen is converted to black display from the all white test pattern (step S63).

  Here, the conversion to black display is performed in units of pixel blocks. FIG. 13 shows a procedure for changing the test pattern. Referring to FIG. 13, the effective projection area is divided into a plurality of pixel blocks (m × n blocks). Using the all-white test pattern (FIG. 13 (1)) as an initial image, the pixel block B (1, 1) at the upper left end is converted into black display in units of pixel blocks (FIGS. 13 (2) and (3)). )). Then, as shown in FIG. 13 (4), when the conversion to the black display for the pixel block B (1, n) at the right end of the first line is completed, the process moves to the second line, and also for the second line, The pixel block B (2, 1) at the left end is converted into black display in order of pixel block (FIGS. 13 (5) and (6)). When the pixel block B (m, n) at the right end of the last line is converted to black display (FIG. 13 (8)), the test pattern change is completed.

  Referring to FIG. 12 again, in step S64, the projection image 110 based on the changed test pattern is captured by the camera 20. The image storage unit 70 stores the captured image as “image B”. FIG. 14 is a diagram illustrating a captured image (image B) acquired by the camera 20 every time the test pattern is changed. Referring to FIG. 14A, in the state where the pixel block converted to black display is outside the screen area, the black display area is not detected in image B. Accordingly, no difference occurs between the image A and the image B. On the other hand, as shown in FIGS. 14B and 14C, in the state where the pixel block converted into the black display is in the screen area, the black display area is detected in the image B. Therefore, a difference occurs between the image A and the image B.

  In step S65 of FIG. 12, the difference detection unit 72 compares the image A and the image B with each other by comparing the image A (all white display) and the image B (partially black display) stored in the image storage unit 70. The difference of is detected. Specifically, the difference detection unit 72 determines whether or not the difference value is greater than or equal to a predetermined threshold value for each pixel block, and generates difference information between the image A and the image B based on the determination result. For example, the difference detection unit 72 sets the variation flag to “0” for a pixel block whose difference value is smaller than a predetermined threshold, and sets the variation flag to “0” for a pixel block whose difference value is equal to or greater than the predetermined threshold. By setting it to “1”, a variation flag binarized by the magnitude of the difference value is generated for each pixel block. Then, the difference detection unit 72 records the variation flag set for each pixel block in the position information table for specifying the position of each pixel block owned in advance (step S66).

  FIG. 15 shows a position information table in which variation flags are recorded for all pixel blocks. In the figure, pixel blocks with the variation flag set to “1” are displayed in black, and pixel blocks with the variation flag set to “0” are displayed in white. That is, the area formed by the black-displayed pixel blocks corresponds to the screen area.

  In step S67 of FIG. 12, the test pattern generation unit 82 determines whether or not the test pattern change for each pixel block has been completed for all the pixel blocks. When the test pattern change has not been completed for all pixel blocks (NO in S67), the process returns to step S03, and the pixel block that is currently converted to black display (or the next line) ) Pixel block is selected and converted to black display. Then, based on the changed test pattern, the position information table is updated by performing the processes of steps S64 to S66.

  In this way, when the change of the test pattern is completed for all the pixel blocks (when YES is determined in S67), the mask information generation unit 76 changes the variation flag (FIG. 15) recorded in the position information table. Based on the above, mask information is generated. Specifically, the mask information generating unit 76 sets each pixel constituting the pixel block having the variation flag “1” to “1”, and sets each pixel constituting the pixel block having the variation flag “0” to “0”. And binarized mask information is generated (step S68). When the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78, the initialization mode ends (step S08), and the process returns to the beginning.

  In the second embodiment described above, the configuration in which the test pattern is changed to black display in units of pixel blocks has been described. However, the test pattern may be changed to black display in units of pixels. In this case, since it is necessary to detect the difference between the captured images by the number of pixels, the processing load increases, but more accurate mask information can be generated.

  Alternatively, in order to generate high-accuracy mask information while avoiding an increase in processing load, in the test pattern change shown in FIG. 13, in each of the horizontal direction and the vertical direction, black is obtained in units of one line or several lines. By changing the display, an approximate screen area (primary detection area) is detected, and then only the primary detection area is changed to black display in units of pixels, thereby providing a precise screen area (secondary detection area). It may be configured to detect.

[Embodiment 3]
FIG. 16 is a flowchart for explaining a video signal processing routine executed by the video signal processing unit 60 in the projector according to the third embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 16, the flowchart according to the third embodiment is different only in that steps S02 to S07 in the flowchart of FIG. 4 are changed to steps S71 to S83.

  As shown in FIG. 16, when the current operation mode is the initialization mode (when YES is determined in S01), the test pattern generation unit 82 generates an all white test pattern. The video signal selection unit 84 outputs the generated all white test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all white test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S71). In step S <b> 72, the projection image 110 based on the all white test pattern is captured by the camera 20. The image storage unit 70 stores the captured image as “image A”.

  Next, the test pattern generation unit 82 generates an all black test pattern (step S73). The video signal selection unit 84 outputs the generated all black test pattern to the display element 40. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-black test pattern, and is projected onto the projection plane 100 by the projection optical system 50 (step S73). In step S <b> 74, the projected image 110 based on the all black test pattern is captured by the camera 20. The image storage unit 70 stores the captured image as “image B (1)”.

  Next, the difference detection unit 72 compares the image A (all white display) and the image B (1) (all black display) stored in the image storage unit 70, thereby comparing the image A and the image B (1). Is detected (step S75). The difference detection unit 72 determines whether or not the difference value is equal to or greater than a predetermined threshold value for each pixel, and generates binarized difference information based on the determination result.

  The mask information generation unit 76 generates mask information based on the difference information generated by the difference detection unit 72. Specifically, the mask information generation unit 76 estimates a screen area from the difference information (step S76).

  Next, the test pattern generation unit 82 changes the test pattern from an all black test pattern to a test pattern in which white areas and black areas are alternately arranged (step S77). FIG. 17 shows a procedure for changing the test pattern. As shown in FIG. 17, the test pattern is changed in each of the horizontal direction and the vertical direction of the screen.

Specifically, referring to FIG. 17A, a plurality of test patterns are generated by changing the number of white areas and black areas alternately arranged in the horizontal direction. For example, in the test pattern H (2) with n = 2, one white area and one black area are arranged (number of arrangements = 2). In the test pattern H (3) with n = 3, two white areas and two black areas are arranged (the number of arrangements = 4). That is, in the nth test pattern H (n), the number of white areas and black areas is 2 ^(n-1) . As an example, when the number of pixels in the horizontal direction is 1024, the number of arrangement can be made to match the number of pixels by generating the test pattern H (11) with n = 11.

  By changing the number of white areas and black areas alternately arranged in the vertical direction by a similar method, a plurality of test patterns are generated in the vertical direction as shown in FIG. .

  In step S77 of FIG. 16, the test pattern generation unit 82 selects the nth test pattern H (n) from the horizontal change patterns shown in FIG. 17A, and sets the test pattern H (n) to the test pattern H (n). change. Note that the test pattern generation unit 82 sequentially selects the test patterns H (2) having the smallest number of arrangements. When the selection of the test pattern in the horizontal direction is completed, the test pattern V (2) having the smallest number of arrangements is sequentially selected for the test pattern in the vertical direction (FIG. 17B).

  In step S78, the projected image 110 based on the changed test pattern H (n) is captured by the camera 20. The image storage unit 70 stores the captured image as “image B (n)”.

  Next, the difference detection unit 72 detects the difference between the image A and the image B (n) by comparing the image A and the image B (n) stored in the image storage unit 70 (step S79). . The difference detection unit 72 determines whether the difference value between the image A and the image B (n) is greater than or equal to a predetermined threshold for each pixel with respect to the pixel located in the screen region estimated in step S76. . Then, by expressing the determination result as “0” or “1”, a binarized variation pattern is generated. For example, “0” is set for pixels whose difference value is equal to or greater than a predetermined threshold, and “1” is set for pixels whose difference value is smaller than the predetermined threshold. Then, the difference detection unit 72 records the generated variation pattern in the position information table for specifying the horizontal position of each pixel on the display element (step S80).

  FIG. 18 shows a position information table for specifying the horizontal position of the pixel on the display element. In the position information table, it is assumed that a pixel displayed in black for one test pattern is expressed as “0” and a pixel displayed in white is expressed as “1”. Therefore, as shown in FIG. 17A, by changing the test pattern from the test pattern H (2) of n = 2 to the test pattern H (11) of n = 11 in order, the horizontal position of each pixel is changed. It is represented by a 10-digit numerical value expressed in binary. For example, since the pixel located at the left end of the screen is always displayed in black in each test pattern, the horizontal position is represented by [0000000], and the pixel located at the right end of the screen is always displayed in white in each test pattern. Therefore, the horizontal position is represented by [1111111111]. As described above, the horizontal position of each pixel on the display element can be expressed by 10-digit numerical values different from each other. Although illustration is omitted, the vertical position of each pixel can be similarly expressed.

  In step S81 of FIG. 16, the test pattern generation unit 82 determines whether or not the test pattern change in the horizontal direction is finished. If the test pattern change in the horizontal direction has not been completed (NO in S81), the process returns to step S77, and the (n + 1) th test pattern H (n + 1) is selected. Then, based on the test pattern after the change, the variation pattern is updated by performing the processing of steps S78 to S80.

  In this way, when the change of the test pattern in the horizontal direction is completed (when YES is determined in S81), the mask information generation unit 76 refers to the position information table and based on the acquired variation pattern. Then, the horizontal position of the pixel on the display element corresponding to the left end and the right end of the screen area is determined.

  Note that the mask information generation unit 76 determines the vertical positions of the pixels on the display element corresponding to the upper end and the lower end of the screen region by performing the processes of steps S77 to S82 also in the vertical direction. Then, the mask information generation unit 76 generates mask information based on the determined pixel position (horizontal pixel position and vertical pixel position) on the display element. When the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78, the initialization mode ends (step S08), and the process returns to the beginning.

  In Embodiment 3 described above, the configuration for specifying the horizontal position and the vertical position for each pixel on the display element has been described. However, when the mask information does not require accuracy in units of pixels, the test pattern The horizontal position and the vertical position may be specified in units of blocks such as 2 pixels or 4 pixels by reducing the number of pixels. According to such a configuration, the processing load in the video signal processing unit can be suppressed.

[Embodiment 4]
FIG. 19 is a diagram showing a state at the time of image projection of the projector according to Embodiment 4 of the present invention. FIG. 20 is a diagram showing a state viewed from the direction B of FIG.

  Referring to FIGS. 19 and 20, the projector according to the fourth embodiment differs from projector shown in FIG. 1 only in that monitor 200 with a touch panel is installed.

  The monitor 200 to which a touch panel is added employs a TFT (Thin Film Transistor) type LCD (Liquid Crystal Display) as a display panel. The touch panel specifically employs a resistive touch panel. When a voltage is applied in the XY direction of the touch panel and the user touches (presses) the surface of the touch panel with a fingertip or a pen, the voltage at the operated position is extracted as a partial pressure, and the extracted partial pressure is converted into XY coordinates. The position operated can be recognized. The touch panel outputs a signal (detection signal) corresponding to the operated position to the video signal processing unit 60.

  The display area of the monitor 200 and the operation area of the touch panel are set to have the same shape and size, and the touch panel is fixed to the monitor 200 so that the operation area and the display area of the monitor 200 overlap. . For this reason, the user can instruct a desired position of the image displayed on the monitor 200 by a touch operation, and can write a handwritten image on the input video.

  In the projector according to the fourth embodiment, the video signal processing unit 60 generates mask information based on the detection signal output from the touch panel. The video signal processing executed by the video signal processing unit 60 in the projector according to Embodiment 4 will be described below with reference to FIG. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 21, first, control unit 90 determines whether or not the current operation mode is an initialization mode in step S01.

  When the current operation mode is the initialization mode (when YES is determined in S01), the test pattern generation unit 82 generates an all black test pattern. The video signal selection unit 84 outputs the generated all black test pattern to the display element 40 in response to the mode switching signal. Thereby, in the display element 40, the light emitted from the light source 30 becomes image light corresponding to the all-black test pattern and is projected onto the projection plane 100 by the projection optical system 50 (step S91).

  In step S <b> 92, the projected image 110 based on the all black test pattern is captured by the camera 20. The captured image is displayed on the monitor 200 as a background image.

  When the user confirms the screen area on the captured image displayed on the monitor 200, the user touches (draws) the operation area of the touch panel with a pen or the like so as to fill the screen area (step S93). During the operation, the control unit 90 periodically monitors a detection signal from the touch panel. When the touch panel is touched, the control unit 90 recognizes the operated position based on the detection signal and also determines the XY of the operation position. Position information indicating the coordinates is output to a drawing control unit (not shown) and a mask information generation unit 76 that generate image data representing an image to be combined with the input video.

  The drawing control unit generates video data based on the position information input from the control unit 90 so that an image (drawing image) representing a drawing locus is superimposed on the position represented by the position information on the input video. To do. As a result, a composite image in which the drawn image is superimposed on the all black test pattern is projected onto the projection plane 100.

  The mask information generation unit 76 generates mask information based on the position information input from the control unit 90. At this time, the mask information generation unit 76 identifies the drawing area based on the position information input from the control unit 90, and recognizes this as a screen area. Thereafter, the mask information generation unit 76 generates mask information based on the recognized screen area. Specifically, the binarized mask information is generated with the position (pixel) in the screen area set to “1” and the position (pixel) outside the screen area set to “0”.

  In step S94, the all white test pattern is projected onto the projection plane 100 again. At this time, based on the mask information generated by the mask information generation unit 76, the mask video generation unit 80 converts the all white test pattern into a test pattern for displaying a partial area in black. Specifically, the mask video generation unit 80 calculates the signal value of each pixel in which the mask information is “0” by taking the logical product of the all white test pattern and the mask information for each corresponding pixel. Forced conversion to “0”.

  In step S95, the user checks the projected image 110 when the all white test pattern is projected in step S94, and confirms that there is no white display area other than the screen area. When it is confirmed that there is no white display area other than the screen area (YES in S95), the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78 (step S97). The initialization mode ends (step 08).

  On the other hand, when it is confirmed that there is a white display area other than the screen area by looking at the projected image 110 when the all white test pattern is projected (NO in S95), the user draws The image is corrected (step S96).

  The drawing image is corrected by the user shifting the background image displayed on the monitor 200 in the vertical and horizontal directions, or by enlarging or reducing the background image. Hereinafter, a specific procedure for correcting a drawn image will be described with reference to FIGS.

  22 (1) and 22 (2) are diagrams showing the display area (operation area of the touch panel) of the monitor 200. FIG. In FIG. 22 (1), a captured image when an all-black test pattern is projected is displayed as a background image. When the user draws on the touch panel using a pen or the like along a locus as indicated by a line L1 in FIG. 22B, a composite image in which the drawn image is superimposed on the background image is displayed on the monitor 200. Further, the video signal processing unit 60 performs data processing so that the drawn image is synthesized with the all-black test pattern, so that a synthesized image in which the drawn image is superimposed on the all-black test pattern is transferred from the projection optical system 50 to the projection surface. 100 is projected.

  At this time, when the screen 120 displayed on the monitor 200 and the actual screen 120 have the same position and size, as shown in FIG. The position and size can be accurately reflected in the image projected on the projection plane 100. On the other hand, when the position and the size of the screen 120 displayed on the monitor 200 and the actual screen 120 do not match, for example, as shown in FIG. Is shifted between the monitor 200 and the screen 120, and the position and size of the locus L1 of the touch operation cannot be accurately reflected in the projected image.

  Therefore, in the case shown in FIG. 23B, the user shifts the background image to the right by operating the up / down / left / right shift buttons provided on the outer periphery of the display area of the monitor 200 (FIG. 23). 24 (B)). Thereby, the position of the screen 120 displayed on the monitor 200 and the actual position of the screen 120 can be matched. Thereafter, when the drawing area is erased (reset) as shown in FIG. 24C, the user performs a touch operation (drawing) in the operation area of the touch panel with a pen or the like so as to fill the screen area again.

  Referring to FIG. 21 again, when the drawn image is corrected by the above-described method (step S96), the user confirms the screen area on the captured image displayed on monitor 200 and fills this screen area. As described above, a touch operation is performed in the operation area of the touch panel with a pen or the like (step S93).

  The mask information generation unit 76 generates mask information based on the position information input from the control unit 90. Thereafter, the all white test pattern converted using the mask information is projected onto the projection plane 100 again. When it is confirmed from the projected image 110 at this time that there is no white display area other than the screen area (YES in S95), the mask information generated by the mask information generation unit 76 is final. Is stored in the mask information storage unit 78 as typical mask information (step S97), and the initialization mode ends (step 08).

  As described above, according to the fourth embodiment of the present invention, the user can generate mask information in real time by an easy operation such as a touch operation on the touch panel. For this reason, the mask information can be generated easily and accurately.

[Embodiment 5]
FIG. 25 is a diagram showing a state at the time of image projection of the projector according to Embodiment 5 of the present invention. FIG. 26 is a diagram showing a state viewed from the direction B of FIG.

  Referring to FIGS. 25 and 26, the projector according to the fifth embodiment is different from the projector shown in FIG. 1 only in that an external input unit 210 is provided instead of camera 20.

  The external input unit 210 receives image data input from an external video supply device (not shown) such as a PC or a camera. The image data received by the external input unit 210 includes binarization data created by graphic calculation processing of the PC and indicating the shape of the screen 120, and binarization created based on image data captured by the camera. Contains data. Instead of an external video supply device, image data may be input from a memory slot provided in the projector 10. As will be described later, the video signal processing unit 60 generates mask information based on these binarized data.

  FIG. 27 is a flowchart illustrating a video signal processing routine executed by video signal processing unit 60 in the projector according to the fifth embodiment. This video signal processing is executed according to a program stored in advance by the control unit 90 (FIG. 3) for each frame.

  Referring to FIG. 27, the flowchart according to the fifth embodiment is different only in that steps S02 to S07 in the flowchart of FIG. 4 are changed to steps S101 to S106.

  As shown in FIG. 27, first, in step S01, the control unit 90 determines whether or not the current operation mode is the initialization mode. When the current operation mode is the initialization mode (when YES is determined in S01), the mask information generation unit 76 reads the image data received by the external input unit 210 (step S101). The mask information generation unit 76 generates binarized mask information based on the read image data (step S102).

  Next, in step S103, the all-white test pattern is again projected on the projection plane 100. At this time, the mask video generation unit 80 converts a part of the all-white test pattern into a test pattern for displaying black based on the mask information generated by the mask information generation unit 76. Specifically, the mask video generation unit 80 calculates the signal value of each pixel in which the mask information is “0” by taking the logical product of the all white test pattern and the mask information for each corresponding pixel. Forced conversion to “0”.

  In step S105, the user confirms that there is no white display area other than the screen area by looking at the projected image 110 when the all white test pattern is projected in step S103. When it is confirmed that there is no white display area other than the screen area (YES in S105), the mask information generated by the mask information generation unit 76 is stored in the mask information storage unit 78 (step S106). The initialization mode ends (step 08).

  On the other hand, when the user sees the projected image 110 when the all white test pattern is projected and confirms that there is a white display area other than the screen area (NO determination in S105), the mask is displayed. Information adjustment is performed (step S104).

  Adjustment of the mask information is performed by the user operating an operation button provided on the input operation unit. The operation buttons include an enlargement / reduction button for enlarging / reducing the image and a shift button for shifting the image vertically and horizontally. The user sets the mask information adjustment amount by operating these buttons while viewing the projected image 110 when the all white test pattern is projected. The mask information generation unit 76 can adjust the mask information according to the set adjustment amount. On the projection surface 100, an all white test pattern converted so that a part of the area is displayed in black based on the adjusted mask information is projected. In this way, the processes in steps S103 to S105 are repeatedly executed until it is confirmed in step S105 that there is no white display area other than the screen area. Then, the mask information with the white display area within the screen area is stored in the mask information storage unit 78 as final mask information (step S106).

  In the fifth embodiment, the mask information is adjusted based on the projection image when the all white test pattern is projected. However, the zoom function and shift function installed in the projection optical system 50 are used. It is also possible to employ a configuration in which the projected image is finely adjusted. In this case, the shift position and zoom position of the projection optical system 50 are adjusted so that the white display area is within the screen area.

  As described above, according to the fifth embodiment of the present invention, the mask information is generated based on the image data given to the external input unit. For this reason, the processing load of the video signal processing is suppressed, and the mask information can be easily generated.

  In this embodiment, a liquid crystal projector is used as the projector, but the present invention is not limited to this. For example, the technology of the present invention may be applied to other projectors such as a DLP (Digital Light Processing) (registered trademark) projector.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  DESCRIPTION OF SYMBOLS 10 Projector, 20 Cameras, 30 Light source, 40 Display element, 50 Projection optical system, 60 Image signal processing part, 70 Image storage part, 72 Difference detection part, 74 Threshold control part, 76 Mask information generation part, 78 Mask information storage part , 80 Mask image generation unit, 82 Test pattern generation unit, 84 Video signal selection unit, 86 Mode switching unit, 90 Control unit, 100 Projection plane, 110 Projected image, 120 screen, 200 Monitor, 210 External input unit, 760 Mask information Generation circuit, 762 pixel number conversion unit, 764 distortion correction unit, 766 angle-of-view distortion information storage unit.

Claims (6)

A light source;
A video signal processing unit that converts an input video signal to generate a video signal for a projected video;
Based on the video signal generated by the video signal processing unit, a display element that modulates the light emitted from the light source to generate video light;
A projection-type image display device comprising: a projection optical system that projects image light generated by the display element onto a projection plane;
The projection surface has a non-display area that does not display an image and a display area that displays an image.
The video signal processor is
Display area information input means for inputting display area information indicating the display area on the projection plane;
Mask information generating means for generating mask information for masking image light in correspondence with the non-display area based on the display area information;
A projection-type video display device, comprising: a mask video generation unit that converts the input video signal into a mask video signal for displaying the non-display area in black based on the mask information.   The video signal processing unit switches between a mask mode in which the mask video signal generated by the mask video generation means is supplied to the display element and a normal mode in which the input video signal is directly supplied to the display element. The projection display apparatus according to claim 1, further comprising mode switching means for operating the display element. The display area input unit includes an imaging unit that captures a projected image when a test pattern is projected on the projection plane and generates a captured image;
The mask information generation means compares a difference value between a plurality of captured images generated by the imaging means when a plurality of test patterns having different brightness are projected on the projection plane, and a predetermined threshold value, Generating the mask information based on the comparison result;
The projection display apparatus according to claim 1, wherein the predetermined threshold is configured to be changeable according to an environment in which the projection plane is installed. Image adjustment means for shifting the display position of the image projected on the projection surface or changing the display size;
The mask information generation unit is configured to finely generate the mask information generated based on an image adjustment amount specified by the image adjustment unit when image light based on the mask video signal is projected onto the projection plane. The projection display apparatus according to claim 1, further comprising a mask information adjusting unit for performing adjustment. The display area input unit includes an imaging unit that captures a projected image when a test pattern is projected onto the projection plane and generates a captured image;
The video signal processor is
A first test pattern in which the entire screen is displayed in a single color and a second test pattern in which the screen is divided into a plurality of pixel blocks and the brightness is changed from the first test pattern in units of pixel blocks are generated. A test pattern generating means;
The mask information generation unit projects the first captured image generated by the imaging unit when the first test pattern is projected onto the projection plane and the second test pattern onto the projection plane. 2. The projection display apparatus according to claim 1, wherein the mask information is generated in units of pixel blocks based on a difference value from the second captured image generated by the imaging unit when the image information is generated. The display area input unit includes an imaging unit that captures a projected image when a test pattern is projected on the projection plane and generates a captured image;
The video signal processor is
Test pattern generating means for generating a test pattern having a first area and a second area, which are alternately arranged along a predetermined direction of the display screen and have different brightness,
The test pattern generation means generates a plurality of test patterns by changing the number of the first and second regions arranged on the display screen, and based on the generated plurality of test patterns Identify the position of each pixel on the display screen in the predetermined direction,
The mask information generation means is based on a difference value between a plurality of captured images generated by the imaging means when the plurality of test patterns are projected on the projection plane, and a position of each pixel in the predetermined direction. The projection display apparatus according to claim 1, wherein the mask information is generated.

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