JP2021086140A - Image projection apparatus and image determination method - Google Patents

Abstract

To provide an image projection apparatus and an image determination method that, when an abnormal image is generated, can detect the generation of the abnormal image more reliably than before.SOLUTION: An image projection apparatus 1 comprises a display device 103, a projection optical system 107, an image forming optical system 105, an image pick-up device 106, a light path branching device 104, and a detection unit. The display device outputs light based on light input thereto. The projection optical system outputs projection light based on the light from the display device. The image forming optical system forms the light from the display device into an image. The image pick-up device converts the light formed into the image by the image forming optical system into an electrical signal to create an image. The light path branching device branches the light from the display device into light toward the projection optical system and light toward the image forming optical system. The detection unit compares a first image as an input image with a second image picked up by the image pick-up device to detect the generation of an abnormal image.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image projection device and an image determination method.

An image projection device (projector) that projects and displays an image based on an input video signal is equipped with a plurality of input terminals such as an RGB terminal, an HDMI (registered trademark) terminal, and a video terminal, and a computer is provided via these terminals. And connected to AV equipment. In such a projector, when a failure such as a device error or a temperature abnormality occurs during use, it is common to save the details of the failure and the operating state at the time of the failure as log information. By analyzing the stored log information, it is possible to analyze the content of the failure and the cause of the failure even after a certain amount of time has passed since the failure occurred.

Further, there is also known a method in which a projected image projected on a screen is captured by an image sensor, and an abnormality is detected based on an input image to be projected and a projected image captured by the image sensor.

However, in the conventional log information storage method, the log information is stored only when a failure occurs. Therefore, for example, even if the projector itself is supposed to be operating normally, if there is an abnormality in the actually projected image due to some trouble that is not detected as a failure, the log information cannot be saved.

In addition, in the abnormality detection method based on the input image to be projected and the projected image projected on the screen, etc., when projecting to a three-dimensional object other than the screen such as projection mapping or picking system, the image actually input to the projector and the actual image are used. The appearance changes depending on the projected image. In such a case, even if the input image and the projected image captured by the image sensor are compared, they do not match, and it is erroneously determined that there is an abnormality.

The present invention has been made in view of the above, and provides an image projection device and an image determination method capable of reliably detecting the occurrence of an abnormality as compared with the conventional case when an abnormality occurs in the projected image. It is to be.

In order to solve the above-mentioned problems and achieve the object, the image projection apparatus according to the embodiment of the present invention includes a display element, a projection optical system, an imaging optical system, an imaging element, an optical path branching element, and the like. It is provided with a detection unit. The display element outputs light based on the input light. The projection optical system outputs projected light based on the light from the display element. The imaging optical system forms an image of light from a display element. The image sensor captures the light imaged by the imaging optical system. The optical path branching element splits the light from the display element into light to the projection optical system and light to the imaging optical system. The detection unit compares the first image as an input image with the second image captured by the image sensor, and detects the occurrence of an abnormal image.

According to the present invention, it is possible to provide an image projection device or the like that can reliably detect the occurrence of an abnormal image as compared with the conventional case when an abnormal image is generated.

FIG. 1 is a diagram showing a hardware configuration of an image projection device according to the first embodiment. FIG. 2 is a functional block diagram for explaining the function of the control unit included in the image projection device according to the embodiment. FIG. 3 is a flowchart showing the flow of the abnormal image detection process of the image projection device. FIG. 4 is a diagram showing a hardware configuration of the image projection device 1 according to the second embodiment. FIG. 5 is a flowchart showing the flow of the abnormal image detection process of the image projection device according to the second embodiment. FIG. 6 is a flowchart showing the flow of the abnormal image detection process of the image projection device according to the third embodiment.

Hereinafter, the image projection device and the image determination method according to the embodiment will be described in detail with reference to the drawings.

(First Embodiment)
FIG. 1 is a diagram showing a hardware configuration of the image projection device 1 according to the first embodiment. As shown in FIG. 1, bus line P, optical engine 10, CPU (Central Processing Unit) 111, ROM (Read Only Memory) 12, SDRAM (Synchronous Dynamic Random Access Memory) 13, NVRAM (Non-VRAM) It includes 14, a fan 15, a power supply unit 16, an operation unit 17, a remote control receiving unit 18, an external I / F19, a network I / F20, and a media I / F21. Digital signals such as HDMI (registered trademark) and analog video signals such as VGA and component signals are input to the image projection device 1.

The bus line P is an address bus, a data bus, or the like for electrically connecting each component.

The optical engine 10 projects a projected image on the screen 5 as a projected object based on the input signal according to the control signal from the CPU 111. The optical engine 10 includes a light source unit 101, an illumination optical system unit 102, a DMD (Digital Micromirror Device) 103, a fixed optical path branching element 104, an imaging optical system 105, an imaging element 106, and a projection optical system unit 107. To be equipped with.

The light source unit 101 irradiates the illumination optical system unit 102 with light according to a control signal from the CPU 111. The light source unit 101 includes a light source 101a and a light source control unit 101b. The light source 101a is a light emitting device such as an LED. The light source control unit 101b controls the light source 101a according to a control signal from the CPU 111. For example, the light source control unit 101b drives a plurality of light emitting units included in the light source 101a to emit light in response to a control signal. As the drive signal, a rectangular wave, a sine wave, or a voltage waveform having a predetermined waveform shape can be used.

The illumination optical system unit 102 guides the light emitted from the light source unit 101 to the DMD 103. The illumination optical system unit 102 includes, for example, a color wheel 102a, a light tunnel 102b, a relay lens 102c, a cylinder mirror 102d, and a reflection mirror 102e.

The color wheel 102a has a disk in which a plurality of segments (transmission regions) that transmit only light in a specific wavelength region are arranged in the rotation direction. The light emitted from the light source unit 101 is separated into light of each color by the passing segment of the rotating color wheel 102a. The light that passes through the color wheel 102a and repeats each color every unit time is emitted toward the light tunnel 102b.

The light tunnel 102b is formed of, for example, flat glass laminated in a polygonal tubular shape. The inner surface of the light tunnel 102b is vapor-deposited with silver, a dielectric multilayer film, or the like, and reflects light. The light tunnel 102b guides the light emitted from the color wheel 102a to the relay lens 102c with uniform illuminance.

The relay lens 102c is formed by a combination of two lenses. The relay lens 102c corrects the axial chromatic aberration of the light emitted from the light tunnel 102b and collects the light. The light that has passed through the relay lens 102c is incident on the DMD 103 via the cylinder mirror 102d and the reflection mirror 102e.

In the illumination optical system unit 102, at the timing when each color light emitted through the color wheel 102a is applied to the display element, a modulation operation corresponding to the color light is performed. Therefore, it is necessary to synchronize the output timing of the drive signal for causing the display element to perform the modulation operation with the rotation timing of the color wheel 102a. For such synchronization, the illumination optical system unit 102 is provided with a configuration for detecting the rotational position of the color wheel 102a. Specifically, the color wheel unit is provided with a position sensor for detecting that the marker provided on a part of the color wheel 102a is positioned at the rotation reference position. When the marker faces the position sensor, the position sensor outputs a position detection signal indicating that the marker has reached the rotation reference position. The synchronization control is performed based on this position detection signal.

The DMD 103 is a display element that outputs light based on the input light. That is, the DMD 103 is a display element controlled by the CPU 11 that modulates the light guided by the illumination optical system unit 102 to generate a display image and outputs the light as the display image. The DMD 103 has a micromirror, and the CPU 11 drives the micromirror on and off according to the image data to modulate the input light. As an alternative display element to the DMD 103, for example, a liquid crystal panel can be used.

The fixed optical path branching element 104 branches the light emitted from the DMD 103 into light to the projection optical system unit 107 and light to the imaging optical system 105.

The imaging optical system 105 forms an image of the light from the DMD 103. That is, the image pickup optical system 105 is an optical system that forms an image of the light emitted from the fixed optical path branching element 104 on the image pickup device 106. With this imaging optical system 105, the image on the DMD 103 is imaged on the image pickup device 106 in a state where there is no focus shift.

The image sensor 106 converts the light imaged by the image pickup optical system 105 into an electric signal to generate an image (imaging process). That is, the image sensor 106 images a subject image including the projected image on the DMD 103. The image sensor 106 is, for example, a COMS type or CCD type image sensor. The image captured by the image pickup device 106 is passed to the control unit 3 realized by the CPU 11 or the like as a comparison image.

The projection optical system unit 107 outputs the projected light based on the light from the DMD 103. That is, the projection optical system unit 107 projects the light from the fixed optical path branching element 104 onto the screen 5. As a result, the image displayed on the DMD 103 is projected on the screen 5. The projection optical system unit 107 includes a projection lens 107a and a projection optical system sensor 107b. The projection lens 107a magnifies the image generated by the DMD 103. There may be a plurality of projection lenses 107a. Further, the projection optical system unit 107 may further include an optical element such as a mirror.

The CPU 111 reads a program or data from a storage device such as the ROM 12 onto the SDRAM 13 as a work area and executes processing to realize control of the entire image projection device 1 and a function as a control unit 3 described later. A part or all of the functions of the CPU 111 may be realized by an electronic circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

Further, for example, when the power supply power is supplied to the power supply unit 16 connected to the commercial power supply, the CPU 111 starts according to the control program stored in advance in the ROM 12, gives a control signal to turn on the light source 101a, and turns on the light source 101a. Is rotated at a predetermined rotation speed. When the power supply of the power supply is started in this way, the optical engine 10 is in a state where the image can be displayed, and the power from the power supply unit 16 is further supplied to various other components. Further, when the power supply unit 16 is disconnected from the commercial power supply (that is, when it receives an OFF operation), the CPU 111 receives a power supply OFF signal from the power supply unit 16 and turns off the light source 101a. After that, when a predetermined time elapses, the CPU 111 gives a control signal to the fan 15 to stop the CPU 111, and ends its own control process.

The ROM 12 is a non-volatile semiconductor memory (storage device) capable of holding programs and data even when the power is turned off. The ROM 12 stores programs and data such as BIOS (Basic Input / Output System) and OS settings that are executed at startup.

The SDRAM 13 is a volatile semiconductor memory (storage device) that temporarily holds programs and data, and operates in synchronization with the system bus.

The NVRAM 14 is a non-volatile memory (storage device) in which programs and various data are stored.

The fan 15 rotates / stops based on the control signal from the CPU 11 to exhaust the air inside the housing of the image projection device 1 and cool the image projection device 1.

The power supply unit 16 is a circuit that controls the electric power supplied to the image projection device 1. The power supply unit 16 sends a power supply OFF signal to the CPU 11, for example, when the power supply unit as a part of the operation unit 17 is turned off, for example, when it is disconnected from the commercial power supply.

The operation unit 17 has various keys and buttons for the user to input an operation instruction to the image projection device 1. The operation unit 17 receives, for example, instruction operations such as a projection image size adjustment operation, a color tone adjustment operation, a focus adjustment operation, a keystone adjustment operation, a power mode change, and an image projection mode change, and the received operation content. Is output to the CPU 11. Further, the operation unit 17 has various lamps (LEDs and the like), a display unit, a speaker, and the like, and may be used as an information presentation unit that presents information such as the state and settings of the image projection device to the user.

The remote control receiving unit 18 is a receiving circuit that receives communication from the remote control. The remote control receiver 18 accepts instruction operations from the remote controller such as, for example, a projection image size adjustment operation, a color tone adjustment operation, a focus adjustment operation, a keystone adjustment operation, a power mode change, and an image projection mode change. The received operation content is output to the CPU 11.

The external I / F19 is an interface for connecting an external device such as a personal computer. Control signals and image data from an external device are input to the image projection device 1 via the external I / F19.

The network I / F20 is an interface for data communication using a communication network such as the Internet.

The media I / F 21 controls reading or writing (storage) of data to a recording medium such as a flash memory.

FIG. 2 is a functional block diagram for explaining the function of the control unit 3 included in the image projection device 1 according to the embodiment. The control unit 3 is configured to have the same function as a general computer in which various interfaces such as CPU 11, ROM 12, SDRAM 13, NVRAM 14, and external I / F 19 are connected by a bus. That is, the control unit 3 is a function realized by the CPU 111 reading a program or data from the ROM 12 or the like onto the SDRAM 13 as a work area and executing the process.

As shown in FIG. 2, the control unit 3 includes a signal processing unit 31, a video processing unit 32, an operation control unit 33, and an image comparison unit 34 as specific functions.

The signal processing unit 31 performs processing for processing an image such as an RGB or YUV signal according to the input signal. For example, when the digital signal is used as an input signal, the signal processing unit 31 converts it into a bit format defined by the video processing unit 32 according to the number of bits of the input signal. Further, when the analog signal is used as an input signal, the signal processing unit 31 performs A / D conversion processing or the like for digitally sampling the analog signal, and inputs an RGB or YUV format signal to the video processing unit 32.

The video processing unit 32 performs digital image processing and the like according to the input signal. Specifically, the image processing unit 32 is appropriate according to the input signal, the function to be provided, the characteristics of the drive system, such as the scaler function such as contrast, brightness, saturation, hue, RGB gain, sharpness, and scaling. Perform various image processing. The video processing unit 32 outputs the input signals obtained by executing these digital image processing to the operation control unit 33 and the image comparison unit 34.

The operation control unit 33 determines the drive conditions of the color wheel 102a that colors the white light according to the input signal, the DMD 103 that selects light emission, and the light source control unit 101b that controls the drive current of the light source 101a, respectively. Give a drive instruction to.

The image comparison unit 34 compares the first image as an input image with the second image captured by the image sensor 106, and detects the occurrence of an abnormal image. That is, the image comparison unit 34 combines the input image obtained as a result of digital image processing by the image processing unit 32 and the image obtained by converting the light from the fixed optical path branching element 104 into an electric signal by the image sensor 106. Make a comparison. The image obtained by converting the light from the fixed optical path branching element 104 into the image sensor 106 electric signal is referred to as an "immediately before projection image". The image immediately before projection is an example of the second image.

During normal operation, the input image obtained as a result of digital image processing by the image processing unit 32 and the image immediately before projection captured by the image sensor 106 match. On the other hand, if there is an abnormality in the operation control unit 33, the light source 101a, the DMD103, the memory, or if there is a bug in the software processing, the input image and the image immediately before projection do not match. It becomes.

The image comparison unit 34 compares the input image and the image immediately before projection, and if they do not match, detects an abnormality in the image immediately before projection (or detects that the image immediately before projection is an abnormal image) and logs. Save information and captured images.

Next, the abnormal image detection process of the image projection device 1 according to the first embodiment will be described.

FIG. 3 is a flowchart showing the flow of the abnormal image detection process of the image projection device 1. As shown in FIG. 3, first, the signal processing unit 31 determines whether or not the video signal is input via the external I / F19 or the like (step S1). When the signal processing unit 31 determines that the video signal has not been input via the external I / F19 or the like, it determines whether or not the video signal has been continuously input (No in step S1). On the other hand, when the signal processing unit 31 determines that the video signal has been input via the external I / F19 or the like (Yes in step S1), the signal processing unit 31 performs processing for processing the video according to the input signal. The video processing unit 32 executes digital image processing or the like in response to the input signal, and outputs the processed signal as an input image signal to the optical engine 10.

The operation control unit 33 causes the image pickup device 106 to take an image of the projected image branched to one side from the fixed optical path branching element 104 (step S2). Further, a projected image is projected on the screen 5 via the projection optical system unit 107 based on the light branched from the fixed optical path branching element 104 to the other.

The image comparison unit 34 compares the input image output from the image processing unit 32 with the image immediately before projection captured by the image sensor 106 (step S3).

When the image comparison unit 34 determines that the input image and the image immediately before projection do not match (mismatch) as a result of the comparison in step S3, the occurrence of an abnormal image is detected (Yes in step S4), and the abnormal image is displayed. An error notification for notifying the occurrence is executed (step S5). In this error notification, information for notifying the occurrence of an abnormal image is displayed on the screen 5, a sound for notifying the occurrence of the abnormal image is output, and a lamp for notifying the occurrence of the abnormal image is turned on or blinks. Etc. can be adopted.

On the other hand, the image comparison unit 34 does not detect the occurrence of an abnormal image when it is determined that the input image and the image immediately before projection match as a result of the comparison in step S3 (No in step S4), and steps S1 to 1 again. The process of S3 is repeatedly executed.

After the error notification in step S5, the image comparison unit 34 includes image data of the image immediately before projection captured by the image sensor 106, input signal type, resolution, frequency, and image adjustment information (each information such as brightness, contrast, and hue). , Each parameter such as lamp usage time and temperature, and error code are saved in ROM 12 and NVRAM 14 as log information (step S6).

The saved log information is automatically transferred to a dedicated management server via RS232C, a network such as a wireless LAN or a wired LAN, or automatically saved in a USB memory or the like connected to an external I / F19. It is also possible.

As described above, the image projection device 1 according to the first embodiment includes a DMD 103 as a display element, a projection optical system unit 107 as a projection optical system, an imaging optical system 105, an image sensor 106, and a fixed optical path branching. It includes an element 104 and an image comparison unit 34 as a detection unit. The DMD 103 outputs light based on the input light. The projection optical system unit 107 outputs the projected light based on the light from the DMD 103. The imaging optical system 105 forms an image of the light from the DMD 103. The image pickup device 106 converts the light imaged by the imaging optical system 105 into an electric signal to generate an image. The fixed optical path branching element 104 splits the light from the DMD 103 into light to the projection optical system unit 107 and light to the imaging optical system 105. The image comparison unit 34 compares the first image as an input image with the second image captured by the image sensor 106, and detects the occurrence of an abnormal image.

Therefore, the occurrence of an abnormal image can be detected by comparing the input image with the image immediately before projection immediately before being actually projected on the screen 5. Therefore, when the occurrence of an abnormal image cannot be detected due to a hardware abnormality or software bug, even if it is projected on a three-dimensional object other than the screen, the abnormal image is not affected by the projected object. It is possible to accurately detect the occurrence and save abnormal images and log information.

As a result, when an abnormal image occurs, it is possible to reliably detect the occurrence of the abnormal image as compared with the conventional case, and it is possible to shorten the determination of the failure content and the cause of the failure related to the abnormal image.

(Second Embodiment)
The image projection device 1 according to the first embodiment includes an image immediately before projection obtained by converting the projected light branched by the fixed optical path branching element 104 into an electric signal by the image pickup element 106, and an input image processed by digital image processing. By comparing with, the occurrence of an abnormal image was detected. However, in the case of such a configuration, since the projected light is branched by the fixed optical path branching element 104, the projected image actually projected on the screen 5 may be darkened by the amount of the branching. ..

On the other hand, the image projection device 1 according to the second embodiment detects the occurrence of an abnormal image by comparing the input image with the image immediately before projection without darkening the projected image actually projected on the screen 5. Is something that can be done.

FIG. 4 is a diagram showing a hardware configuration of the image projection device 1 according to the second embodiment. In FIG. 4, the same reference numerals are given to the parts common to those in FIG. 1 described above, and detailed description thereof will be omitted.

As shown in FIG. 4, the image projection device 1 according to the second embodiment includes a movable optical path branch element 108 and a branch drive unit 109.

The movable optical path branching element 108 branches the light emitted from the DMD 103 into light to the projection optical system unit 107 and light to the imaging optical system 105. Further, the movable optical path branching element 108 is an optical path branching element that is movable between the first position and the second position.

Here, as shown in FIG. 4, the first position is a position for arranging the movable optical path branching element 108 in order to branch the light output from the DMD 103 to the imaging optical system 105. It exists on the optical path output from the DMD 103. Arranging the movable optical path branching element 108 at the first position is called "turning on the movable optical path branching element 108". The second position is a position where the movable optical path branching element 108 retracts so as not to branch the light output from the DMD 103 to the imaging optical system 105, and exists outside the optical path output from the DMD 103. .. Arranging the movable optical path branching element 108 at the second position is called "turning off the movable optical path branching element 108".

The branch drive unit 109 moves the movable optical path branch element 108 between the first position and the second position. That is, the branch drive unit 109 arranges the movable optical path branch element 108 between the first position in which the branch is turned on and the second position in which the branch is turned off according to the control signal from the operation control unit 33. Switch with.

The operation control unit 33 controls the branch drive unit 109 according to a change in the input signal. That is, the operation control unit 33 determines whether or not the signal corresponding to the change in the input signal state is the signal to be subjected to the abnormal image detection processing (signal determination processing). Further, the operation control unit 33 triggers a change in the state of the input signal to the image projection device 1 to set the arrangement of the movable optical path branching element 108 to the branch ON state and the branch OFF. The branch drive unit 109 is controlled so as to switch between the second position and the state.

Here, "change in the state of the input signal to the image projection device 1" means, for example, "no signal → with signal", "with signal → no signal", and "change the video signal to a different signal (for example, resolution)". ”,“ Change of input terminal (for example, change from VGA to HDMI (registered trademark), etc.) ”.

FIG. 5 is a flowchart showing the flow of the abnormal image detection process of the image projection device 1. In parallel with the abnormal image detection process shown in FIG. 5, the projection process according to the input signal is executed. That is, as shown in FIG. 5, first, the operation control unit 33 determines whether or not the input signal state has changed (step S101). When the operation control unit 33 determines that the input signal state has not changed, it continuously continues the projection and appropriately determines whether or not the input signal state has changed (No in step S101).

On the other hand, when the operation control unit 33 determines that the input signal state has changed (Yes in step S101), the motion control unit 33 Mutes the projection with the change in the input signal state as a trigger (step S102). Here, the projection Mute is a process executed to hide the flickering of the screen when the projection setting is changed in the signal determination process of the next step, and typically a black monochromatic image is displayed. This is the process of projecting.

Next, the operation control unit 33 performs signal determination processing (step S103). That is, the operation control unit 33 determines whether or not the signal corresponding to the change in the input signal state is the signal that is the target of the abnormal image detection process.

Next, the operation control unit 33 controls the branch drive unit 109 so as to turn on the movable optical path branch element 108 (step S104), and releases the projection Mute (step S105).

Next, the motion control unit 33 converts the light branched to one side from the movable optical path branching element 108 into an electric signal by the image pickup device 106 to generate an image (step S106). Further, the operation control unit 33 controls the branch drive unit 109 so as to turn off the movable optical path branch element 108 (step S107). Further, the projection optical system unit 107 projects a projected image onto the screen 5 based on the light branched from the movable optical path branching element 108 to the other.

The image comparison unit 34 compares the input image output from the image processing unit 32 with the image immediately before projection captured by the image sensor 106 (step S108).

When the image comparison unit 34 determines that the input image and the image immediately before projection do not match (mismatch) as a result of the comparison in step S108, the occurrence of an abnormal image is detected (Yes in step S109), and the abnormal image is displayed. An error notification for notifying the occurrence is executed (step S110).

On the other hand, when the image comparison unit 34 determines that the input image and the image immediately before projection match as a result of the comparison in step S3, it does not detect the occurrence of an abnormal image (No in step S109), and steps S101 to step S101 again. The process of S108 is repeatedly executed.

After the error notification in step S110, the image comparison unit 34 includes image data of the image immediately before projection captured by the image sensor 106, input signal type, resolution, frequency, and image adjustment information (each information such as brightness, contrast, and hue). , Each parameter such as lamp usage time and temperature, and error code are saved in ROM 12 and NVRAM 14 as log information (step S111).

The saved log information is automatically transferred to a dedicated management server via RS232C, a network such as a wireless LAN or a wired LAN, or automatically saved in a USB memory or the like connected to an external I / F19. It is also possible.

As described above, the image projection device 1 according to the second embodiment has the movable optical path branching element 108 at the first position where the light from the DMD 103 is imaged on the image sensor 106 and the light from the DMD 103. It includes a second position that does not form an image on the image sensor 106, a branch drive unit 109 that moves between the image sensor 106, and an operation control unit 33 that controls the branch drive unit 109. The operation control unit 33 controls the branch drive unit 109 according to a change in the input signal.

For example, the movable optical path branching element 108 is arranged at a first position which is an arrangement position for branching the light from the DMD 103 to the imaging optical system 105 only when the input signal changes. Will be done. Further, when a projected linear image for comparison with the input image is captured, the movable optical path branching element 108 is a second arrangement position for not branching the light from the DMD 103 to the imaging optical system 105. It is placed at the position of.

Therefore, the movable optical path branching element 108 is arranged in the optical path only when the image immediately before projection used for the abnormality detection process is captured, and the decrease in the amount of light in the abnormality detection process can be minimized. As a result, the occurrence of an abnormal image can be detected by comparing the input image with the image immediately before projection without darkening the projected image actually projected on the screen 5.

(Third Embodiment)
In the second embodiment, a case where the abnormal image detection process is executed by using a change in the state of the input signal as a trigger has been described. On the other hand, in the third embodiment, a case where the abnormal image detection process is executed with the setting changed by the menu operation as a trigger will be described.

The operation control unit 33 controls the branch drive unit 109 according to the change in the setting. That is, the motion control unit 33 changes various settings of the image projection device 1 as a trigger when the settings are changed by the menu operation (setting change process). Further, the operation control unit 33 determines whether or not the setting change processing is a setting change (setting change related to video) that is the target of the abnormal image detection processing. Further, the operation control unit 33 is in the first position where the arrangement of the movable optical path branching element 108 is in the branch ON state, triggered by the setting being changed by the menu operation via the operation unit 17 or the remote control receiving unit 18. The branch drive unit 109 is controlled so as to switch between and the second position in which the branch is turned off.

Here, "change of setting by menu operation" means, for example, "electric point ON-> power OFF", "with signal-> no signal", "change video signal to different signal (for example, change resolution)", It means "change of input terminal (for example, change from VGA to HDMI (registered trademark), etc.)".

FIG. 6 is a flowchart showing the flow of the abnormal image detection process of the image projection device 1. In parallel with the abnormal image detection process shown in FIG. 6, the projection process according to the input signal is executed. That is, as shown in FIG. 6, first, the operation control unit 33 determines whether or not the setting change request has been input (step S201). When it is determined that the setting change request has not been input (No in step S201), the operation control unit 33 appropriately determines whether or not the setting change request has been input while continuing the projection.

On the other hand, when it is determined that the setting change request has been input (Yes in step S201), the operation control unit 33 performs the setting determination process (step S202). Further, the operation control unit 33 determines whether or not the setting change process is a setting change related to video (step S203).

Next, the operation control unit 33 controls the branch drive unit 109 so as to turn on the movable optical path branch element 108 (step S204), and the light branched from the movable optical path branch element 108 to one side is captured by the image sensor 106. Is converted into an electric signal to generate an image (step S205). Further, the operation control unit 33 controls the branch drive unit 109 so as to turn off the movable optical path branch element 108 (step S206). Further, the projection optical system unit 107 projects a projected image on the screen 5 based on the light branched from the movable optical path branching element 108 to the other.

The image comparison unit 34 compares the input image output from the image processing unit 32 with the image immediately before projection captured by the image sensor 106 (step S207).

When the image comparison unit 34 determines that the input image and the image immediately before projection do not match (mismatch) as a result of the comparison in step S108, it detects that an abnormal image has occurred (Yes in step S208), and the image comparison unit 34 detects the abnormal image. An error notification for notifying the occurrence is executed (step S209).

On the other hand, when the image comparison unit 34 determines that the input image and the image immediately before projection match as a result of the comparison in step S3, it does not detect the occurrence of an abnormal image (No in step S208), and steps S201 to step S201 again. The process of S207 is repeatedly executed.

After the error notification in step S110, the image comparison unit 34 includes image data of the image immediately before projection captured by the image sensor 106, input signal type, resolution, frequency, and image adjustment information (each information such as brightness, contrast, and hue). , Each parameter such as lamp usage time and temperature, and error code are saved in ROM 12 and NVRAM 14 as log information (step S210).

The saved log information is automatically transferred to a dedicated management server via RS232C, a network such as a wireless LAN or a wired LAN, or automatically saved in a USB memory or the like connected to an external I / F19. It is also possible.

As described above, the image projection device 1 according to the third embodiment has the movable optical path branching element 108 at the first position where the light from the DMD 103 is imaged on the image sensor 106 and the light from the DMD 103. It includes a second position that does not form an image on the image sensor 106, a branch drive unit 109 that moves between the image sensor 106, and an operation control unit 33 that controls the branch drive unit 109. The operation control unit 33 controls the branch drive unit 109 according to the change in the setting.

For example, the movable optical path branching element 108 is arranged at a first position which is an arrangement position for branching the light from the DMD 103 to the imaging optical system 105 only when the setting is changed. Ru. Further, when the image immediately before projection for comparison with the input image is captured, the movable optical path branching element 108 is a second arrangement position for not branching the light from the DMD 103 to the imaging optical system 105. Is placed at the position of.

Therefore, the movable optical path branching element 108 is arranged in the optical path only when the image immediately before projection used for the abnormality detection process is captured, and the decrease in the amount of light in the abnormality detection process can be minimized. As a result, the occurrence of an abnormal image can be detected by comparing the input image with the image immediately before projection without darkening the projected image actually projected on the screen 5.

The program for realizing the function of the image projection device 1 described above is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versailles Disk), or a file. It may be configured to be recorded and provided on a computer-readable recording medium such as a USB (Universal Serial Bus), or may be provided or distributed via a network such as the Internet. Further, various programs may be provided by being incorporated in a non-volatile recording medium such as a ROM in advance.

It should be noted that the above-described embodiment and each modification are preferable examples of the present invention, but the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention. ..

1 Image projection device 3 Control unit 10 Optical engine 11 CPU
12 ROM
13 SDRAM
14 NVRAM
15 Fan 16 Power supply unit 17 Operation unit 18 Remote control receiver 19 External I / F
20 Network I / F
21 Media I / F
31 Signal processing unit 32 Video processing unit 33 Operation control unit 34 Image comparison unit 101 Light source unit 102 Illumination optical system unit 102a Color wheel 102b Light tunnel 102c Relay lens 102d Cylinder mirror 102e Reflection mirror 103 DMD
104 Fixed optical path branching element 105 Imaging optical system 106 Image pickup element 107 Projection optical system unit 108 Movable optical path branching element

Japanese Patent No. 4333269

Claims (7)

A display element that outputs light based on the input light,
A projection optical system that outputs projected light based on the light from the display element, and
An imaging optical system that forms an image of light from the display element,
An image sensor that converts the light imaged by the imaging optical system into an electrical signal to generate an image,
An optical path branching element that splits the light from the display element into light to the projection optical system and light to the imaging optical system.
A detection unit that detects the occurrence of an abnormal image by comparing the first image as an input image with the second image captured by the image sensor, and
An image projection device comprising. In order to prevent the optical path branching element from branching the light from the display element to the imaging optical system and the first position which is the arrangement position for branching the light from the display element to the imaging optical system. The drive unit to be moved between the second position, which is the arrangement position of
A control unit that controls the drive unit and
The image projection device according to claim 1, further comprising. The image projection device according to claim 2, wherein the control unit controls the drive unit in response to a change in an input signal. The image projection device according to claim 2, wherein the control unit controls the drive unit in response to a change in setting. The invention according to any one of claims 1 to 4, wherein when the detection unit determines that the second image is an abnormal image, the second image and the log information are stored in the memory. Image projection device. The image projection device according to any one of claims 1 to 5, wherein the display element is a digital micromirror device. The light from the display element that outputs light based on the input light is branched into light to the projection optical system and light to the imaging optical system by the optical path branching element.
The light from the display element is imaged by the imaging optical system.
The imaged light is converted into an electric signal by an image sensor to generate an image, and the image is generated.
To detect the occurrence of an abnormal image by comparing the first image as an input image with the second image captured by the image sensor.
An image determination method comprising.

Images