JP2006293124A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To highly reliably project normal images onto a screen, without having to require a user to perform a complex operation, in a projector used in various conditions. <P>SOLUTION: When the screen onto which images from the projector 10 to be projected is of a transmission type and a rear projection type, an image, corresponding to an external image signal can be displayed on it by switching to a left/right reversed image, in which the image is reversed from left to right. In addition, when the screen onto which images from the projector 10 to be projected is of a front projection type, the image, corresponding to the external image signal can be displayed, as it is, without having to turn the image from the left to right. When the projector 10 is suspended from the ceiling side, such that it is turned upside down, the image, corresponding to the external image signal, can be displayed by switching the image to an inverted image (vertically inverted image), in which the image is turned by 180°. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projector that projects an image using a light modulation device such as a liquid crystal panel.

  As a conventional projector, there is a projector that can switch and display a front projection that projects an image from the front side of the screen and a rear projection that projects an image from the back side of the screen.

In such a projector, for example, an appropriate image can be projected onto a screen by performing driver control of the liquid crystal module using a left / right inversion control signal (Patent Document 1). In another projector, for example, an appropriate image can be projected onto a screen by automatically switching the scanning direction using a connector provided at a place where the projector is stored (Patent Document). 2). Further, another projector displays a non-inverted image and an inverted image to allow the user to select a normal image and project an appropriate image on the screen based on the selected image. (Patent Document 3).
JP-A-6-138431 JP-A-6-205347 Japanese Patent Laid-Open No. 11-64974

  However, in the method of preparing the left / right inversion control signal or the method of allowing the user to select a normal image, the user needs to actively perform a switching operation until the projection image can be normally observed. The operation becomes complicated.

  In addition, projectors that have a connector for automatically detecting the storage at the projector storage location are based on the premise that the projector is stored in a specific cabinet. When an image is projected on a rear projection screen that does not exist, there is a problem that the projected image is inverted.

  Therefore, an object of the present invention is to project a normal image with high certainty on a screen without requiring a complicated operation from a user in a projector used in various states.

  In order to solve the above problems, a projector according to the present invention includes: (a) a projector main body having an image optical system for image formation and image projection; and a video circuit for operating the video optical system; and (b) a projector main body. A light projecting means for causing predetermined inspection light to be incident on a screen on which an image is to be projected; (c) a sensor for detecting reflected light from the screen on which the predetermined inspection light is incident; and (d) a detection output of the sensor. And (e) based on the determination result of the determination unit, whether the image to be projected by the projector main body is reversed or not is reversed based on whether the screen is a rear projection type or a front projection type. An image processing unit.

  In the projector, the determination unit determines whether the screen is a rear projection type or a front projection type based on a detection output of a sensor that detects reflected light from the screen. Regardless of the presence or absence, the screen type can be reliably determined. Therefore, it is possible to automatically project an image without left-right inversion according to the screen type simply by installing the projector, and the user does not need to perform an operation of switching the setting.

  In a specific aspect or aspect of the present invention, the light projecting unit projects an inspection image corresponding to predetermined inspection light on the screen via the projector body. In this case, an inspection image formed by the projector body can be used as inspection light.

  In another specific aspect of the present invention, the light projecting unit projects a first luminance image and a second luminance image different from the first luminance with a time difference as the inspection image. In this case, the screen type can be determined more accurately by using the intensity difference of the reflected light obtained by projecting images with different brightness projected in time series.

  In another specific aspect of the present invention, the light projecting unit projects an image including a first luminance region and a second luminance region as an inspection image. In this case, the screen type can be determined more accurately by using the difference in intensity of the reflected light obtained by projecting images having areas with different luminances.

  In another specific aspect of the present invention, the determination unit determines whether the output of the sensor exceeds a predetermined threshold value. In this case, the screen type can be easily determined using the reflectance on the screen.

  In another specific aspect of the invention, the imaging optical system projects a light source, a light modulation unit that modulates illumination light emitted from the light source, and image light that is formed through the light modulation unit. System. In this case, the signal processing in the video circuit can be switched according to the type of the screen, and the signal for driving the light modulation unit can be easily switched to the left and right inverted image.

[First Embodiment]
FIG. 1 is a block diagram conceptually illustrating the projector according to the first embodiment of the invention. The projector 10 controls the operation of the main body optical device 11, which is also called an optical engine unit, a power supply device 14 for supplying electric power to circuits and others, cooling fan units 15 A and 15 B for air-cooling lamp light sources, and the like. Circuit device 16, a CCD camera 17 for detecting reflected light from a screen arranged on the front side of the projector 10, an acceleration sensor 18 for detecting the tilt state of the projector 10, and an outer case 19 covering the entire device. With. The circuit device 16 is composed of electronic components mounted on a printed circuit board and is housed in an upper layer in the outer case 19 but is shown outside the outer case 19 for convenience.

  Among these, the main body optical device 11 includes a light source device 30 that generates illumination light with uniform light source light, a divided illumination system 40 that divides illumination light that has passed through the light source device 30 into three colors of red, green, and blue, An optical modulator 50 that is illuminated by illumination light of each color emitted from the divided illumination system 40, a cross dichroic prism 60 that synthesizes the modulated light of each color that has passed through the light modulator 50, and an image that is emitted from the cross dichroic prism 60 A projection lens 70 for projecting light onto a screen (not shown). The light source device 30, the divided illumination system 40, the light modulation unit 50, the cross dichroic prism 60, and the projection lens 70 constitute an image optical system, and are substantially entirely housed in a light shielding case member 11a. .

  Here, the light source device 30 is reflected by the lamp light source 31 that forms a substantially dot-like light emitting portion, a concave mirror 32 that has a parabolic or other surface shape and reflects the light source light from the lamp light source 31, and the concave mirror 32. And a uniformizing optical system 33 that makes the light source light uniform illumination light. Among these, the lamp light source 31 is a lamp light source such as a high-pressure mercury lamp, and generates substantially white light source light. The concave mirror 32 reflects the light emitted from the lamp light source 31 and makes it incident on the uniformizing optical system 33 as a substantially parallel light beam. Although not described in detail, the homogenizing optical system 33 converts a pair of fly-eye lens arrays, a superimposing lens for superimposing wavefront-divided light by the lens array, and illumination light into a predetermined polarization component. A polarization conversion member.

  The divided illumination system 40 is a color separation optical system that forms illumination light of each color, and includes first and second dichroic mirrors 41a and 41b and reflection mirrors 42a, 42b, and 42c. The split illumination system 40 separates the illumination light that has passed through the uniformizing optical system 33 into three light beams of red light, blue light, and green light. That is, the first dichroic mirror 41a reflects the red light LR among the three colors of red, blue, and green (R, G, and B) and transmits the blue light LB and the green light LG. The second dichroic mirror 41b reflects the blue light LB among the incident blue light LB and green light LG and transmits the green light LG. Although not shown, a relay lens for compensating for an optical path difference between green and other colors is disposed around the reflecting mirrors 42b and 42c on the optical path of the green light LG. A field lens is disposed on the output side of the divided illumination system 40, that is, on the emission side of the three mirrors 42a, 41b, and 42c so as to face the liquid crystal panels 51r, 51b, and 51g of the respective colors.

  The light modulation unit 50 includes three liquid crystal panels (liquid crystal display panels) 51r, 51b, and 51g on which the three colors of illumination lights LR, LB, and LG are respectively incident. Although not shown, three sets of polarizing filters are arranged so as to sandwich the liquid crystal panels 51r, 51b, 51g. Each liquid crystal panel 51r, 51b, 51g and a pair of polarizing filters sandwiching them constitute a liquid crystal light valve for each color that modulates the illumination light LR, LB, LG of each color on a pixel basis.

  In the light modulation unit 50, the red light LR reflected by the reflection mirror 42a enters the image forming area of the liquid crystal panel 51r, and the blue light LB reflected by the dichroic mirror 41b enters the image forming area of the liquid crystal panel 51b. The green light LG that is incident and reflected by the reflecting mirror 42c enters the image forming area of the liquid crystal panel 51g. Each liquid crystal panel 51r, 51b, 51g changes the spatial distribution of the polarization direction with respect to the incident illumination light. That is, each color light LR, LB, LG incident on each of the liquid crystal panels 51r, 51b, 51g is in pixel units according to a drive signal or a control signal input as an electrical signal to each of the liquid crystal panels 51r, 51b, 51g. Thus, the polarization state is adjusted, and the intensity is modulated in units of pixels as it passes through a polarization filter (not shown).

  The cross dichroic prism 60 is a light combining optical system for combining color images, and includes a first dichroic film (specifically, a dielectric multilayer film) 61 for reflecting red light and a green light reflecting lens. The second dichroic film (specifically, a dielectric multilayer film) 62 is arranged in an X shape. The cross dichroic prism 60 reflects the red light LR from the liquid crystal panel 51r by the first dichroic film 61 and emits it to the right in the traveling direction, and the blue light LB from the liquid crystal panel 51b through the dichroic films 61 and 62. The green light LG from the liquid crystal panel 51g is reflected by the second dichroic film 62 and emitted to the left in the traveling direction.

  The image light synthesized by the cross dichroic prism 60 in this way passes through a projection lens 70 which is a projection optical system, and then is a reflection type normal front projection type screen SR1 shown in FIG. 2A or FIG. ) And a normal rear projection type screen SR2 shown in FIG.

  The power supply device 14 turns on the lamp light source 31 provided in the light source device 30 with a desired luminance, and supplies appropriate power to the cooling fan units 15A and 15B and the circuit device 16.

  Each of the cooling fan units 15A and 15B includes a fan, a motor, and the like, and can supply air to the exterior case 12 or exhaust the exterior of the exterior case 12 based on a control signal from the circuit device 16. A cooling airflow can be formed in the case 12 at an appropriate flow rate.

  The circuit device 16 includes an image processing unit 81 to which an external image signal such as a video signal is input, a panel driving unit 82 that drives each liquid crystal panel 51r, 51b, 51g based on the output of the image processing unit 81, and a CCD camera. 17 is operated appropriately, an image analysis unit 92 that reads necessary information from the measurement signal, an inclination detection unit 93 that reads necessary information from the output of the acceleration sensor 18, and operations of these circuit portions 81, 92, 93, etc. And a main control unit 88 that controls the entire system. Here, the image processing unit 81 and the panel driving unit 82 function as a video circuit that directly operates the main body optical device 11 that is a video optical system. That is, the main body optical device 11, the image processing unit 81, the panel driving unit 82, and the like are projector main bodies for displaying images.

  In the circuit device 16, the image processing unit 81 includes a correction unit 81 a that appropriately corrects the input external image signal, and an OSDC unit 81 b that displays character information or the like instead of or superimposing the external image signal. Prepare. The former correction unit 81a performs various image processing such as color correction and distortion correction on the external image signal based on a command from the main control unit 88, inverts the left and right of the image, and rotates the image by 180 °. I will let you. Specifically, when the screen on which the image from the projector 10 is to be projected is a transmissive type and a rear projection type, that is, the observer OB observes from the opposite side of the projector 10 as shown in FIG. In this case, the image corresponding to the external image signal can be switched to a horizontally reversed image obtained by reversing the left and right and can be displayed. When the screen on which the image from the projector 10 is to be projected is a front projection type, that is, when the observer OB observes from the projector 10 side as shown in FIG. 2A, it corresponds to an external image signal. The image is displayed as it is without reversing the left and right. When the projector 10 is suspended from the ceiling side and turned upside down, the image corresponding to the external image signal can be switched to an inverted image (upside down image) rotated 180 ° and displayed. On the other hand, the latter OSDC unit 81b is for displaying various display information on the operation setting / confirmation menu, operation state, processing result, etc. of the projector 10 on the screen based on the command from the main control unit 88. . That is, the OSDC unit 81b performs modulation corresponding to various display information including characters, figures and the like that are not related to the external image signal on the liquid crystal panels 51r, 51b, 51g, and on the screen via the projection lens 70. The various display information is projected onto the screen. Note that, when the correction unit 81a causes the correction unit 81a to switch the image corresponding to the external image signal to a horizontally reversed image as shown in FIG. 2B, the OSDC unit 81b horizontally reverses the display information including characters and figures. To display. Further, when the correction unit 81a switches the image corresponding to the external image signal to the upside down image and displays it, the OSDC unit 81b displays the display information including characters, figures, etc. upside down.

  The panel drive unit 82 generates a drive signal for adjusting the state of each of the liquid crystal panels 51r, 51b, 51g based on the image signal after image processing output from the image processing unit 81. Accordingly, an image as a transmittance distribution can be formed in the light valve composed of the liquid crystal panels 51r, 51b, 51g and the polarizing plates associated therewith corresponding to the image signal input from the image processing unit 81. .

  The image analysis unit 92 can capture the images of the screens SR1 and SR2 (see FIGS. 2A and 2B) arranged on the front surface of the projector 10 by operating the CCD camera 17 at an appropriate timing. Specifically, among the images captured by the CCD camera 17, taking into account the projection magnification and projection direction of the image light by the projector 10, an image within a predetermined angle range corresponding to the central area of the screen is cut out and averaged. . The averaged luminance of the image is used as a reflected light amount for screen type discrimination. At this time, if the main control unit 88, the image processing unit 81, and the like, which are light projecting units, are operated as appropriate, two types of images having different brightness values can be projected as inspection light on the screen and reflected. The change in the amount of light can be obtained. Such a difference in the amount of reflected light can be used to determine whether the screen is a reflection type and a normal front projection type, or whether the screen is a transmission type and a rear projection type. When the screen is a front projection type as shown in FIG. 2A, the amount of light reflected from the screen SR1 increases, and the CCD camera 17 in the case of projecting two types of images with different brightness on the screen SR1. The detected light amount difference due to is relatively large. Further, when the screen is a rear projection type as shown in FIG. 2B, the amount of light reflected from the screen SR2 is reduced, and the CCD camera 17 when two types of images having different brightness are projected on the screen SR2. The detected light amount difference due to is relatively small. In the detection of the light amount difference as described above, the CCD camera 17 is a sensor that detects reflected light together with the image analysis unit 92.

  The tilt detection unit 93 includes an AD converter, which converts the output of the acceleration sensor 18 into digital data and calculates the tilt angle of the projector 10 from the value. It is determined from the calculated tilt angle of the projector 10 whether the projector 10 is suspended upside down.

  The main control unit 88 is a control unit including a microcomputer or the like, and operates based on a program appropriately prepared for controlling the image processing unit 81, the image analysis unit 92, the inclination detection unit 93, and the like. The main control unit 88 includes a storage unit 88a that is a storage unit, and reads various data necessary for the operation of the image processing unit 81, the image analysis unit 92, the inclination detection unit 93, and the like from the storage unit 88a as needed. Necessary information is appropriately stored in the storage unit 88a. Explaining the main operation, for example, the main control unit 88 determines whether the target on which the projector 10 projects an image via the image analysis unit 92 is a front projection type screen or a rear projection type screen. Judgment can be made. That is, the main control unit 88 functions as a determination unit that determines whether the screen is a rear projection type or a front projection type based on information from the image analysis unit 92. Further, the main control unit 88 is used in a normal upright state with the projector 10 placed on the stand via the tilt detection unit 93 or suspended in the upside down state suspended from the ceiling side. Can be determined.

  The key input unit 95 connected to the main control unit 88 is for inputting a user instruction to the main control unit 88. At this time, the OSDC unit 81b, the panel driving unit 82, the liquid crystal panels 51r, 51b, 51g, and the like provided in the image processing unit 81 provide information such as an operation setting / confirmation menu, operation state, and processing result by the main control unit 88 to the user. It functions as a GUI type input device presented in

  Hereinafter, the main operation of the projector 10 will be described focusing on the description of the operation of the main control unit 88.

  3 and 4 are flowcharts conceptually illustrating the up / down / left / right display switching by the projector 10. First, when the projector 10 is connected to a power source and the switch of the power supply device 14 is turned on, the main control unit 88 allows the projector 10 to be activated by turning on the lamp light source 31 (step S11). Next, the main control unit 88 causes the image processing unit 81 to operate appropriately to project an inspection image made up of a uniform white image on the screen via the light modulation unit 50 or the like (step S12). Next, the main control unit 88 operates the image analysis unit 92 as appropriate to cause the CCD camera 17 to capture an image on the screen, that is, a screen image, and to detect the luminance of the screen image as the amount of reflected light (step S13). The reflected light amount data is temporarily stored in the storage unit 88a. Next, the main control unit 88 operates the image processing unit 81 as appropriate to project an inspection image made up of a uniform black image on the screen via the light modulation unit 50 or the like (step S14). Next, the main control unit 88 operates the image analysis unit 92 as appropriate to cause the CCD camera 17 to capture a screen image and to detect the luminance of the screen image as the amount of reflected light (step S15). This reflected light amount data is also temporarily stored in the storage unit 88a.

  Next, the main controller 88 determines whether or not the difference or ratio between the reflected light amount obtained in step S13 and the reflected light amount obtained in step S15 is equal to or greater than a predetermined threshold (step S17). As a result, when it is determined that the difference or ratio with respect to the reflected light amount is equal to or greater than the threshold value, it is determined that the screen is of the reflective type and of the normal front projection type, and a special image is obtained with respect to the external image signal. Processing is not performed, and display maintenance is performed so that the external image signal is normally displayed on the left and right as it is (step S18). On the other hand, if it is determined in step S17 that the difference or ratio with the amount of reflected light is less than the threshold value, it is determined that the screen is a transmissive type and a rear projection type, and the image processing unit 81 uses the external image signal. The left-right inverted image is converted into a left-right inverted image, and the converted left-right inverted image is projected on the screen (step S19). Here, the main control unit 88 and the image processing unit 81 function as an image processing unit that switches whether the image to be projected on the screen is reversed horizontally.

  Next, the main control unit 88 operates the tilt detection unit 93 as appropriate so that the output of the acceleration sensor 18 is appropriately captured and calculates the tilt angle of the projector 10 (step S21). Next, the main control unit 88 determines whether or not the projector 10 is in the upside down state, that is, whether the tilt angle obtained in step S21 is in the normal range or whether this tilt angle is in the upside down range ( Step S22). As a result, when the inclination angle is determined to be in the normal range, it is determined that the projector 10 is placed upright on the table, and special image processing is performed on the external image signal. The display is maintained so that the external image signal is displayed upright at the original top and bottom without being performed (step S23). On the other hand, if it is determined in step S22 that the tilt angle is in the upside down range, it is determined that the projector 10 is in an inverted state in which the projector 10 is hung from the ceiling side and turned upside down. Conversion processing to an inverted image rotated 180 ° with respect to the image signal is performed, and the vertically inverted image after conversion is projected on the screen (step S24).

  Next, the main control unit 88 determines whether or not a command for requesting a setting change is input via the key input unit 95 (step S31). That is, when the user of the projector 10 thinks that the image displayed on the screen is not appropriate in the vertical and horizontal directions, he / she operates the key input unit 95 to request activation of the display change menu. The main control unit 88 operates the image processing unit 81 in response to this request, and displays four patterns of regions obtained by inverting an image including characters and the like up and down and left and right on the screen via the light modulation unit 50 and the like. (Step S32). Next, the main control unit 88 waits for the user to select and confirm one of the four pattern regions via the key input unit 95, and performs an appropriate inversion corresponding to the region thus selected. Inversion processing is set and stored in the storage unit 88a, and necessary inversion processing is performed on the external image signal by the image processing unit 81 (step S33). That is, based on the settings stored in the storage unit 88a, the image processing unit 81 (1) does not perform inversion processing, (2) only upside-down processing, (2) only left-right inversion processing, (4) up / down / left / right One of the inversion processes is selected and executed, and an appropriate image desired by the user is displayed on the screen.

  If it is determined that the command for changing the setting in step S31 has not been input, it is determined whether an operation to turn off the power switch of the projector 10 has been performed (step S34), and the power switch is turned off. When the operation is not performed, the process returns to step S31 and the processes of steps S32 and S34 are repeated. When the operation for turning off the power switch is performed, the entire process is terminated when the power is turned off.

  In the above description, in steps S12 and S14, a pair of inspection images, which are a white image and a black image, are projected in time series on the screen via the light modulation unit 50 or the like. As long as a desired accuracy can be ensured, the inspection image to be included can include an intermediate tone such as gray, and can further include a chromatic color.

  Further, the inspection image is not limited to the image projected on the screen using the light modulation unit 50 or the like, and an appropriate light projecting unit provided separately from the light modulation unit 50 can be used. Specifically, as shown in FIG. 1, a spotlight light source 119 is provided so as to be embedded in the front surface of the exterior case 19, and spotlight or the like can be incident on the screen. At this time, the image analysis unit 92 can measure the amount of light reflected from the screen by operating the spotlight light source 119 and the CCD camera 17 in synchronization. Note that the wavelength of the inspection light generated by the spotlight light source 119 is not limited to visible light, and may not be visually detected such as infrared rays.

  In the above description, two types of images having different brightness are projected as inspection light on the screen. However, a single type of bright image is projected as inspection light on the screen, and the amount of reflected light at that time is predetermined. It is also possible to determine whether the screen is a rear projection type or a front projection type based on whether or not the threshold is exceeded.

[Second Embodiment]
The projector according to the second embodiment is a modification of the projector 10 according to the first embodiment shown in FIG. 1 and the like, and parts that are not particularly described are the same as those of the projector 10 according to the first embodiment.

  FIG. 5 is a flowchart conceptually illustrating a partial operation of display switching between up / down / left / right by the projector 10. After allowing the projector 10 to start (step S11), the main control unit 88 causes the image processing unit 81 to operate appropriately to project an inspection image made up of a monochrome pattern image on the screen via the light modulation unit 50 or the like. (Step S112). FIG. 6 shows an example of the inspection image projected in step S112, in which black and white stripes in which a high luminance white region and a low luminance black region are repeated in the horizontal X direction are projected on the screen. . However, the illustrated pattern image is an example, and a black and white check pattern repeated in the X direction and the Y direction can be used as the inspection image. Next, the main control unit 88 operates the image analysis unit 92 as appropriate to cause the CCD camera 17 to capture an image on the screen, that is, a screen image, and to detect the luminance of the screen image as the amount of reflected light (step S113). At this time, the CCD camera 17 cuts out an image of a predetermined area on the center side of the screen with an appropriate scanning line extending in the X direction, and determines a band in which the luminance is uniform and does not change significantly. Then, a pair of luminances obtained by averaging the luminances in adjacent bands are stored in the storage unit 88a as the reflected light amount. Next, the main controller 88 determines whether or not the difference or ratio between the pair of reflected light amounts obtained in step S113 is equal to or greater than a predetermined threshold (step S17). The following is the same as the operation of the first embodiment shown in FIGS.

  In addition, this invention is not restricted to said embodiment, In the range which does not deviate from the summary, it can be implemented in a various aspect, For example, the following deformation | transformation is also possible.

Further, in the above embodiment, even when the screen is a transmissive type and a rear projection type, the projector 10 is described as being placed on a table as shown in FIG. It is also possible to project the image on the front screen through a mirror or the like behind it while being housed in the cabinet. The screen is a transmissive type and the rear projection type In the above description, the image is inverted when the screen is a transmissive type and the rear projection type. However, if the screen is a transmissive type and the rear projection type is used as a reference, When the screen is a reflection type and a front projection type, it is also possible to perform an image inversion process.

  In the above embodiment, the case of synthesizing images by the three color liquid crystal panels 51r, 51b, and 51g has been described. However, the image display device that directly projects the color type liquid crystal panel, and the type in which the liquid crystal panel reflects light. An image display device or an image display device incorporating a light modulation device using, for example, a micromirror as a light modulation device can also automatically switch the image up, down, left, and right using the reflectance of the screen.

It is a block diagram which shows the structure of the projector which concerns on 1st Embodiment. It is a figure explaining the type of screen in which the projector of FIG. 1 is used. 3 is a flowchart for explaining an example of the operation of the projector in FIG. 1. 3 is a flowchart for explaining an example of the operation of the projector in FIG. 1. It is a flowchart explaining operation | movement of the projector which concerns on 2nd Embodiment. An example of the test | inspection image projected with the projector of 2nd Embodiment is shown.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Projector, 11 ... Main body optical device, 14 ... Power supply device, 16 ... Circuit device, 17 ... Camera, 18 ... Acceleration sensor, 19 ... Exterior case, 30 ... Light source device, 33 ... Uniformation optical system, 40 ... Split illumination System: 50 ... Light modulation unit, 51r, 51b, 51g ... Liquid crystal panel, 60 ... Cross dichroic prism, 70 ... Projection lens, 81 ... Image processing unit, 82 ... Panel drive unit, 88 ... Main control unit, 92 ... Image analysis 93: Inclination detection unit 95: Key input unit

Claims (6)

A projector main body having an image optical system for image formation and image projection, and an image circuit for operating the image optical system;
Projection means for causing predetermined inspection light to be incident on a screen on which an image is to be projected by the projector body;
A sensor for detecting reflected light from the screen on which the predetermined inspection light is incident;
Determination means for determining whether the screen is a rear projection type or a front projection type based on a detection output of the sensor;
A projector comprising: an image processing unit that switches between right and left reversal of an image to be projected by the projector body based on a determination result of the determination unit.   The projector according to claim 1, wherein the light projecting unit projects an inspection image corresponding to the predetermined inspection light onto the screen via the projector main body.   The said light projection means projects the image of 1st brightness | luminance and the image of 2nd brightness | luminance different from said 1st brightness | luminance as a said test | inspection image by a time difference, Either of Claim 1 and Claim 2 characterized by the above-mentioned. The projector described in the section.   3. The projector according to claim 1, wherein the light projecting unit projects an image including a first luminance region and a second luminance region different from the first luminance as the inspection image. The projector according to one item.   The projector according to claim 1, wherein the determination unit determines whether the output of the sensor exceeds a predetermined threshold value. The video optical system includes a light source, a light modulation unit that modulates illumination light emitted from the light source, and a projection optical system that projects image light formed through the light modulation unit. The projector according to any one of claims 1 to 5.

Images