JP2012042846A - Projector and projector control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector capable of informing of detailed precautions concerning electric power interruptions.SOLUTION: A projector 1 includes: a cooling control unit 23 for switching between a first cooling state in which a cooling unit (cooling fan 24) is made perform cooling when a light source 11 is turned on and a second cooling state in which the cooling unit is made tentatively keep cooling after the light source 11 is turned off; a first determination unit (control unit 20) for determining whether the electric power from an external power source is interrupted or not in the first cooling state at the time of the last operation; a second determination unit (control unit 20) for determining whether the electric power from the external power source is interrupted or not in the second cooling state at the time of the last operation; and a warning projection control unit (control unit 20) for making an image projection unit 10 project a first warning screen when the first determination unit determines that the electric power from the external source is interrupted and making the image projection unit 10 project a second warning screen when the second determination unit determines that the electric power from the external source is interrupted.

Description

  The present invention relates to a projector and a projector control method.

  2. Description of the Related Art Conventionally, many projectors that modulate light emitted from a light source to form image light and project the image light onto a screen or the like cool the interior of a casing that becomes hot as the light source is turned on. Cooling device (cooling fan or the like). This cooling device continues cooling for a while after the light source is turned off, and suppresses deterioration of various components that may occur when left at a high temperature. The cooling after the light source is turned off is called “cool down” or the like.

  However, a user who is not familiar with how to use such a projector sometimes cuts off power from the commercial power supply before the cool-down is completed. Therefore, the number of times the lamp (light source) is turned on and the number of times cooling is normally completed after the lamp is turned off is counted, and the difference is calculated. A projector for display is disclosed (Patent Document 1).

JP 2006-106639 A

  However, in the projector described in Patent Document 1, it was not possible to determine whether the power was cut off while the lamp was lit or whether the power was cut off during the cool down after the lamp was turned off. For this reason, there has been a problem in that it is impossible to notify the user of detailed precautions regarding power interruption.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A projector according to this application example cools an image projection unit that modulates and projects light emitted from a light source, a housing that houses the image projection unit, and the inside of the housing. A first cooling state in which the cooling unit performs cooling when the light source is turned on, and the cooling unit continues the cooling for a while after the light source is turned off. A cooling control unit that switches between the second cooling state, a first determination unit that determines whether power from an external power source is interrupted in the first cooling state during the previous operation, and the second determination unit during the previous operation. The second determination unit that determines whether or not the power from the external power source is cut off in the cooling state, and the first determination unit determines that the power from the external power source is cut off during the previous operation. In case The projection unit projects a first warning screen, and when the second determination unit determines that power from the external power source has been cut off during the previous operation, the image projection unit displays a second warning screen. And a warning projection control unit for projecting.

  According to such a projector, the cooling control unit has a first cooling state in which the cooling unit performs cooling when the light source is turned on, and a second cooling state in which cooling is continued for a while after the light source is turned off. Switch. The first determination unit determines whether or not power from the external power source is interrupted in the first cooling state during the previous operation. The second determination unit determines whether or not power from the external power source is interrupted in the second cooling state during the previous operation. The warning projection control unit projects the first warning screen when the first determination unit determines that the power was cut off during the previous operation, and the second determination unit cuts off the power during the previous operation. If it is determined that the second warning screen is displayed, the second warning screen is projected. Thereby, the power from the external power source is cut off in the first cooling state (ie, the light source is turned on), or the power from the external power source is cut off in the second cooling state (ie, the cool-down state). It becomes possible to judge whether it was done. The projector can project a warning screen corresponding to each projector.

  Application Example 2 In the projector according to the application example described above, the projector further includes an operation reception unit that receives an operation for instructing to turn on or off the light source, and the first determination unit and the second determination unit include: The operation receiving unit makes a determination when receiving an operation for turning on the light source, and the warning projection control unit is based on a determination result by the first determination unit and the second determination unit. The image projection unit projects the first warning screen or the second warning screen.

  According to such a projector, when the operation for turning on the light source is received, the determination by the first determination unit and the determination by the second determination unit are performed, and the warning projection control unit is based on the determination result. To project the first warning screen or the second warning screen. In other words, when the user performs an operation for turning on the light source, if the power from the external power source was previously shut off in the first cooling state, the projector projects the first warning screen and the second cooling state. If the power from the external power source is cut off in, the projector projects the second warning screen. Thereby, the user can recognize whether or not the power from the external power source was shut down last time when the light source was turned on.

  Application Example 3 In the projector according to the application example described above, the projector further includes an operation reception unit that receives an operation for instructing turning on or off of the light source, and the second determination unit is configured such that the operation reception unit uses the light source. A determination is made when an operation for turning off the light is accepted, and the warning projection control unit determines that the power to the image projection unit is cut when power from the external power source is cut off in the previous second cooling state. A third warning screen is projected.

  According to such a projector, when an operation for turning off the light source is received, the second determination unit performs a determination, and the warning projection control unit causes the third warning screen to be projected based on the determination result. . That is, when the user performs an operation for turning off the light source, the projector projects the third warning screen if the power from the external power source was previously shut off in the second cooling state. As a result, the user can recognize whether or not the power from the external power source was previously shut down in the second cooling state when the light source was turned off.

  Application Example 4 In the projector according to the application example described above, the third warning screen includes a display that prompts the user not to cut off the power from the external power source during the second cooling state. And

  According to such a projector, the third warning screen includes a display prompting the user not to cut off the power from the external power source during the second cooling state. Thereby, the user can recognize that the power should not be cut off during the period of the second cooling state.

  Application Example 5 In the projector according to the application example described above, the first counter is added at the start of the first cooling state and is subtracted at the end of the first cooling state, and is added at the start of the second cooling state. A second counter that is subtracted at the end of the second cooling state, wherein the first determination unit is configured to supply power from the external power source in the first cooling state based on a value of the first counter. The second determination unit determines whether the power from the external power source is interrupted in the second cooling state based on the value of the second counter. Features.

  Such a projector has a first counter and a second counter. The first determination unit determines whether the power is cut off in the first cooling state based on the value of the first counter, and the second determination unit determines the second value based on the value of the second counter. It is determined whether the power is cut off in the cooling state. Thereby, the projector can determine whether or not the power from the external power source is interrupted in the first cooling state by the first counter, and can count the number of times the power is interrupted. In addition, the projector can determine whether or not the power from the external power source is shut off in the second cooling state by the second counter, and can count the number of times the power is shut off.

  Application Example 6 In the projector according to the application example described above, a first flag setting unit that sets a first flag that is set at the start of the first cooling state and cleared at the end of the first cooling state; A second flag setting unit that is set at the start of the second cooling state and is set at a second flag that is cleared at the end of the second cooling state, and the first determination unit includes the first determination unit Based on the value of the flag, it is determined whether power from the external power source has been cut off in the first cooling state, and the second determination unit determines whether the second cooling state is based on the value of the second flag. And determining whether or not power from the external power source is cut off.

  According to such a projector, the first flag is set at the start of the first cooling state and cleared at the end. The second flag is set at the start of the second cooling state and cleared at the end. As a result, the first determination unit determines whether power is shut off in the first cooling state based on the value of the first flag, and the second determination unit determines whether the power is cut off based on the value of the second flag. It can be determined whether or not the power is cut off in the two cooling state.

  Application Example 7 In the projector according to the application example, a third counter that is added when the first flag is not cleared, and a fourth counter that is added when the second flag is not cleared; The first determination unit counts the number of times power from the external power source is cut off in the first cooling state according to the value of the third counter, and the second determination unit includes: The number of times the power from the external power source is cut off in the second cooling state is counted according to the value of the fourth counter.

  According to such a projector, the third counter is added when the first flag is not cleared. The fourth counter is added when the second flag is not cleared. Accordingly, the first determination unit counts the number of times power is cut off in the first cooling state based on the value of the third counter, and the second determination unit determines the power in the second cooling state based on the value of the fourth counter. Can be counted.

  Application Example 8 A projector control method according to this application example includes an image projection unit that modulates and projects light emitted from a light source, a housing that houses the image projection unit, and an interior of the housing. And a cooling unit for cooling the projector, the first cooling state in which the cooling unit performs cooling when the light source is turned on, and the cooling unit after the light source is turned off. A cooling control step for switching between the second cooling state for continuing the cooling for a while, a first determination step for determining whether or not power from the external power source is cut off in the first cooling state during the previous operation, A second determination step of determining whether or not power from the external power source is cut off in the second cooling state during the operation of the first and second determination steps, and the first determination step from the external power source during the previous operation. When it is determined that power has been cut off, the image projection unit projects a first warning screen, and the second determination step determines that power from the external power source has been cut off during the previous operation. A warning projection control step of causing the image projection unit to project a second warning screen.

  According to such a projector control method, it is possible to determine whether power from the external power source is cut off in the first cooling state or whether power from the external power source is cut off in the second cooling state. . The projector can project a warning screen corresponding to each projector.

  Further, when the projector and the control method thereof are constructed using a computer provided in the projector, the form and the application example described above are a program for realizing the function, or the program is stored in the computer. It is also possible to constitute in the form of a recording medium or the like recorded so as to be readable by the user. Recording media include flexible disks, hard disks, CD-ROM (Compact Disk Read Only Memory), DVD (Digital Versatile Disk), Blu-ray Disc (registered trademark), magneto-optical disk, nonvolatile memory card, internal storage of projector Use various computer-readable media such as devices (semiconductor memories such as RAM (Random Access Memory) and ROM (Read Only Memory)) and external storage devices (USB (Universal Serial Bus) memory, etc.). Can do.

It is a perspective view which shows the projector of 1st Embodiment, and is a figure which shows a front surface, an upper surface, and a right side surface. It is a perspective view which shows a projector, and is a figure which shows a back surface, a bottom surface, and a right side surface. The block diagram which shows the circuit structure of a projector. The flowchart of the process when a projector transfers to a power-on state. It is explanatory drawing of a 1st warning screen and a 2nd warning screen, (a) is explanatory drawing of a 1st warning screen, (b) is explanatory drawing of a 2nd warning screen. The flowchart of the process at the time of power-off operation of a projector being made. Explanatory drawing of a 3rd warning screen. Explanatory drawing of a power interruption count display screen. FIG. 6 is a block diagram illustrating a circuit configuration of a projector according to a second embodiment. The flowchart of the process when a projector transfers to a power-on state. The flowchart of the process at the time of power-off operation of a projector being made.

  Hereinafter, embodiments will be described.

(First embodiment)
In the first embodiment, a projector that uses a first counter and a second counter to determine that power from a commercial power source (external power source) has been cut off will be described.

1 and 2 are perspective views illustrating the projector according to the first embodiment. FIG. 1 is a diagram illustrating a front surface, a top surface, and a right side surface. FIG. 2 is a diagram illustrating a back surface, a bottom surface, and a right side surface. It is.
As shown in FIGS. 1 and 2, the projector 1 has a configuration in which the apparatus main body is housed in a housing 2, and a projection lens 13 that projects an image is exposed on the front surface 2 f of the housing 2. ing. On the upper surface 2t of the housing 2, an operation receiving unit 21 for a user to give various instructions to the projector 1 is provided. On the rear surface 2r of the housing 2, a power supply terminal 27 to which power from a commercial power supply is supplied and an image information input unit 31 to which image information is input from an external image supply device (not shown) are provided. The image information input unit 31 includes a plurality of input terminals 31a. Each input terminal 31a is connected to the other end of a cable having one end connected to the image supply device.

  The projector 1 includes a cooling fan 24 (see FIG. 3) inside the housing 2, and can cool the inside of the housing 2 that becomes hot as the light source is turned on. The bottom surface 2 b of the housing 2 is formed with an air inlet 3 a for sucking air from the outside. The air sucked from the air inlet 3 a by the rotation of the cooling fan 24 cooled the inside of the housing 2. Thereafter, the gas is discharged from an exhaust port 3b formed in the right side surface 2s of the housing 2.

FIG. 3 is a block diagram showing a circuit configuration of the projector.
As shown in FIG. 3, the projector 1 includes an image projection unit 10, a control unit 20, an operation reception unit 21, a temperature sensor 22, a cooling control unit 23, a cooling fan 24, a light source control unit 25, a power supply circuit 26, and a power supply terminal 27. The image information input unit 31, the image processing unit 32, the OSD processing unit 33, and the like are included in the housing 2 (see FIGS. 1 and 2).

  The image projection unit 10 includes a light source 11, three liquid crystal light valves 12R, 12G, and 12B as light modulation devices, a projection lens 13 as a projection optical system, a light valve drive unit 14, and the like. The image projection unit 10 modulates the light emitted from the light source 11 with the liquid crystal light valves 12R, 12G, and 12B to form image light, and projects the image light from the projection lens 13 and displays it on the projection surface SC. .

  The light source 11 includes a discharge-type light source lamp 11a made of an ultra-high pressure mercury lamp, a metal halide lamp, or the like, and a reflector 11b that reflects light emitted from the light source lamp 11a toward the liquid crystal light valves 12R, 12G, and 12B. ing. Light emitted from the light source 11 is converted into light having a substantially uniform luminance distribution by an integrator optical system (not shown), and red (R), green (G), and blue, which are the three primary colors of light, by a color separation optical system (not shown). After being separated into each color light component of (B), it enters the liquid crystal light valves 12R, 12G, and 12B, respectively.

  The liquid crystal light valves 12R, 12G, and 12B are configured by a liquid crystal panel in which liquid crystal is sealed between a pair of transparent substrates. In the liquid crystal light valves 12R, 12G, and 12B, a plurality of pixels (not shown) arranged in a matrix are formed, and a driving voltage can be applied to the liquid crystal for each pixel. When the light valve driving unit 14 applies a driving voltage corresponding to the input image information to each pixel, each pixel is set to a light transmittance corresponding to the image information. For this reason, the light emitted from the light source 11 is modulated by transmitting through the liquid crystal light valves 12R, 12G, and 12B, and an image corresponding to the image information is formed for each color light. The formed color images are synthesized for each pixel by a color synthesis optical system (not shown) to form a color image, and then projected from the projection lens 13.

  The control unit 20 includes a CPU (Central Processing Unit), a RAM used for temporary storage of various data, and a non-volatile memory such as a mask ROM, flash memory, FeRAM (Ferroelectric RAM), etc. (Not shown) and functions as a computer. The control unit 20 performs overall control of the operation of the projector 1 by the CPU operating according to a control program stored in a nonvolatile memory.

  Further, the control unit 20 includes a first counter 20a, a first counter previous value storage unit 20b, a second counter 20c, and a second counter previous value storage unit 20d that are stored in a writable nonvolatile memory. I have. The first counter 20a is added at the time when the light source 11 is turned on, that is, at the start of the first cooling state in which the inside of the housing 2 is cooled, and when the light source 11 is turned off, that is, at the end of the first cooling state. Sometimes subtracted. The first counter previous value storage unit 20b stores the value of the first counter 20a and compares it with the value of the first counter 20a at that time when the power is turned on next time. The second counter 20c is added at the start of the second cooling state, which is a cool-down state, and is subtracted at the end of the second cooling state. The second counter previous value storage unit 20d stores the value of the second counter 20c and compares it with the value of the second counter 20c at that time when the power is turned on and off next time.

  The initial value of the first counter 20a is zero. The initial value of the first counter previous value storage unit 20b is 1. The initial value of the second counter 20c is zero. The initial value of the second counter previous value storage unit 20d is 0. Here, the initial value indicates a value at the time of shipment of the projector 1.

  The operation receiving unit 21 receives an input operation from the user, and includes a plurality of operation keys for the user to give various instructions to the projector 1. The operation keys included in the operation accepting unit 21 include a power key for switching on / off the power, an input switching key for switching the input terminal 31a, and a menu for switching display / non-display of a menu screen for performing various settings. There are a key, a cursor key used for moving the cursor on the menu screen, and a determination key for determining various settings. When the user operates (presses) various operation keys of the operation receiving unit 21, the operation receiving unit 21 receives this input operation and outputs an operation signal corresponding to the operation content of the user to the control unit 20. The operation receiving unit 21 may be configured using a remote control (not shown) capable of remote operation. In this case, the remote control transmits an infrared operation signal corresponding to the user's operation content, and a remote control signal receiving unit (not shown) receives this and transmits it to the control unit 20.

  The temperature sensor 22 is composed of a thermistor or the like, detects the temperature inside the housing 2, and outputs the detection result to the cooling control unit 23. The temperature sensor 22 is disposed in a part that generates heat or is easily damaged by heat, such as the light source 11, the liquid crystal light valves 12R, 12G, and 12B, the power supply circuit 26, and the like. Further, instead of directly detecting the temperature inside the housing 2, the temperature inside the housing 2 may be indirectly detected by detecting the temperature of the air discharged from the exhaust port 3 b. Good.

  The cooling control unit 23 controls the start and stop of rotation of the cooling fan 24 based on an instruction from the control unit 20, and the cooling fan 24 based on the instruction from the control unit 20 and the detection result of the temperature sensor 22. The number of rotations (rotational speed) is controlled. Further, the cooling control unit 23 switches between the first cooling state and the second cooling state based on an instruction from the control unit 20. The cooling control unit 23 of the present embodiment can switch the rotation speed of the cooling fan 24 in a plurality of stages. The cooling control unit 23 increases the rotational speed of the cooling fan 24 to suppress the temperature rise as the internal temperature of the housing 2 is higher. When the internal temperature is low, the noise associated with the rotation of the fan. The rotation speed of the cooling fan 24 is reduced to suppress power consumption.

  The cooling fan 24 corresponds to a cooling unit, and includes, for example, an axial fan or a sirocco fan. The cooling fan 24 rotates based on the control of the cooling control unit 23 and sucks outside air from the air inlet 3a, so that the inside of the housing 2 (particularly, the image projection unit 10, the power circuit 26, etc.) is sucked. It cools and the air after cooling is discharged | emitted from the exhaust port 3b. The cooling fan 24 may be composed of a plurality of fans, for example, a fan (intake fan) disposed in the vicinity of the intake port 3a and a fan (exhaust fan) disposed in the vicinity of the exhaust port 3b. It may be comprised including.

  The light source control unit 25 performs an insulation breakdown between an inverter (not shown) that converts a direct current generated by the power supply circuit 26 into an alternating current rectangular wave current and an electrode of the light source lamp 11a to start the light source lamp 11a. An igniter (not shown) for prompting is provided, and lighting of the light source 11 is controlled based on an instruction from the control unit 20. Specifically, the light source control unit 25 can turn on the light source 11 by starting the light source 11 and supplying predetermined power, and can stop the supply of power and turn off the light source 11. The light source control unit 25 can adjust the luminance (brightness) of the light source 11 by controlling the power supplied to the light source 11 based on an instruction from the control unit 20.

  A commercial power source (external power source) such as AC 100 V is supplied from the outside to the power circuit 26 through a power terminal 27. The power supply circuit 26 converts a commercial power supply (AC power supply) into a DC power supply having a predetermined voltage, and supplies power to each unit of the projector 1 including the light source control unit 25. Further, the power supply circuit 26 stops supplying power (operating power) necessary for projecting an image to each unit (power-on state) and operating power supply based on an instruction from the control unit 20. It is possible to switch between a state (standby state) of waiting for an operation for turning on.

  The image information input unit 31 includes various input terminals 31a for connecting to an external image supply device (not shown) such as a personal computer, a video playback device, a memory card, a USB storage, and a digital camera via a cable. (See FIG. 2), and image information (image signal) is input from the image supply device. The image information input unit 31 converts the input image information into image information in a format that can be processed by the image processing unit 32, and outputs the image information to the image processing unit 32.

  The image processing unit 32 converts the image information input from the image information input unit 31 into image data representing the gradation of each pixel of the liquid crystal light valves 12R, 12G, and 12B. Here, the converted image data is for each color light of R, G, B, and is composed of a plurality of pixel values corresponding to all the pixels of each liquid crystal light valve 12R, 12G, 12B. The pixel value determines the light transmittance of the corresponding pixel, and the intensity (gradation) of light emitted from each pixel is defined by the pixel value. The image processing unit 32 performs image quality adjustment processing for adjusting brightness, contrast, sharpness, hue, and the like on the converted image data based on an instruction from the control unit 20, and the processed image data Is output to the OSD processing unit 33.

  The OSD processing unit 33 performs processing for superimposing an OSD (on-screen display) image such as a menu image or a message image on the input image based on an instruction from the control unit 20. The OSD processing unit 33 includes an OSD memory 33a, and stores image data representing graphics, fonts, and the like for forming an OSD image. In the present embodiment, the OSD memory 33a stores image data of a first warning screen, a second warning screen, and a third warning screen, which will be described later. Furthermore, the image data of the power-off number display screen described later is stored.

  When the control unit 20 instructs to superimpose an OSD image, the OSD processing unit 33 reads necessary image data from the OSD memory 33a and generates OSD image data for forming a specified OSD image. Then, the OSD image data is combined with the image data input from the image processing unit 32 so that the OSD image is superimposed at a predetermined position on the input image. The image data combined with the OSD image data is output to the light valve driving unit 14. If there is no instruction to superimpose the OSD image from the control unit 20, the OSD processing unit 33 outputs the image data input from the image processing unit 32 to the light valve driving unit 14 as it is.

  When the light valve driving unit 14 drives the liquid crystal light valves 12R, 12G, and 12B according to the image data input from the OSD processing unit 33, the liquid crystal light valves 12R, 12G, and 12B form images according to the image data, This image is projected from the projection lens 13.

Next, the operation of the projector 1 will be described.
When one end of a power cable (not shown) is connected to the power terminal 27 and a power plug provided at the other end of the power cable is inserted into an outlet, power is supplied to the power circuit 26 from a commercial power source. When power is supplied from the commercial power supply, the power supply circuit 26 supplies power (standby power) to at least the control unit 20 and the operation receiving unit 21, and the control unit 20 receives this power supply and executes the control program. Start following the operation. Immediately after power is supplied from the commercial power supply, the projector 1 is in a standby state (also referred to as a “power-off state”), and the control unit 20 monitors an operation on the power key of the operation reception unit 21. When the power key is operated by the user, the control unit 20 instructs the power supply circuit 26 to start supplying operating power to each unit, and causes the projector 1 to shift to the power-on state.

Next, processing when the projector 1 shifts to the power-on state will be described.
FIG. 4 is a flowchart of processing when the projector 1 shifts to the power-on state.

  When the power-on operation is performed with the power key, the control unit 20 instructs the light source control unit 25 to turn on the light source 11 (step S101). Next, the control unit 20 instructs the cooling control unit 23 to start cooling by the cooling fan 24 (first cooling state) (step S102). Then, the control unit 20 adds 1 to the first counter 20a (step S103). Next, the control unit 20 determines whether or not the value of the first counter 20a is larger than the first counter previous value stored in the first counter previous value storage unit 20b (step S104). The control unit 20 at this time corresponds to a first determination unit. When the value of the first counter 20a is larger than the previous value of the first counter (step S104: YES), the control unit 20 issues an instruction to the OSD processing unit 33 and projects a first warning screen described later (step S105). ). Then, control goes to a step S106. When the value of the first counter 20a is not greater than the previous value of the first counter (step S104: NO), the control unit 20 proceeds to step S106 without executing step S105.

  In step S106, the control unit 20 determines whether or not the value of the second counter 20c is greater than the second counter previous value stored in the second counter previous value storage unit 20d (step S106). The control unit 20 at this time corresponds to a second determination unit. When the value of the second counter 20c is larger than the previous value of the second counter (step S106: YES), the control unit 20 issues an instruction to the OSD processing unit 33 and projects a second warning screen described later (step S107). ). Then, control goes to a step S108. When the value of the second counter 20c is not greater than the previous value of the second counter (step S106: NO), the control unit 20 proceeds to step S108 without executing step S107. Here, the control unit 20 that performs the processing from step S104 to step S107 corresponds to a warning projection control unit.

  In step S108, the control unit 20 stores the value of the first counter 20a in the first counter previous value storage unit 20b (step S108). And the process at the time of the projector 1 shifting to a power-on state is complete | finished.

Here, the first warning screen and the second warning screen will be described.
FIG. 5 is an explanatory diagram of the first warning screen and the second warning screen, FIG. 5A is an explanatory diagram of the first warning screen, and FIG. 5B is a second warning screen. It is explanatory drawing of a screen.

  As shown in FIG. 5A, the first warning screen M1 displays a character string “AC power is cut off during previous light source lighting” as an OSD image. As shown in FIG. 5B, the second warning screen M2 displays a character string “AC power is shut off before the last cool-down is completed” as an OSD image.

  As described above, when the power of the projector 1 is turned on, if the value of the first counter 20a is larger than the previous value of the first counter, the AC light source 11 is turned on, i.e., in the first cooling state. It is determined that the power from the power source (commercial power source) has been cut off, and the fact is notified to the user. Further, when the value of the second counter 20c is larger than the previous value of the second counter, it is determined that the power from the AC power source (commercial power source) is cut off during the previous cool-down, that is, in the second cooling state. Inform the user to that effect.

Next, processing when the power-off operation of the projector 1 is performed will be described.
FIG. 6 is a flowchart of processing when the power-off operation of the projector 1 is performed.

  When the power-off operation is performed with the power key, the control unit 20 determines whether or not the value of the second counter 20c is greater than the second counter previous value stored in the second counter previous value storage unit 20d ( Step S201). The control unit 20 at this time corresponds to a second determination unit. When the value of the second counter 20c is larger than the previous value of the second counter (step S201: YES), the control unit 20 issues an instruction to the OSD processing unit 33 and projects a third warning screen described later (step S202). ). When the power key is pressed, the process proceeds to step S203. When the value of the second counter 20c is not greater than the previous value of the second counter (step S201: NO), the control unit 20 proceeds to step S203 without executing step S202. Here, the control unit 20 that performs the processing from step S201 to step S202 corresponds to a warning projection control unit.

  In step S203, the control unit 20 stores the value of the second counter 20c in the second counter previous value storage unit 20d (step S203). Next, the control unit 20 instructs the light source control unit 25 to turn off the light source 11 (step S204). Then, the control unit 20 subtracts 1 from the first counter 20a (step S205). Then, the control unit 20 issues an instruction to the cooling control unit 23, ends the first cooling state, and starts cool-down (second cooling state) (step S206). In the present embodiment, it is assumed that the control unit 20 includes a timer (not shown) and measures a predetermined time (for example, 30 seconds) for performing cool-down.

  The control unit 20 adds 1 to the second counter 20c (step S207). Then, the control unit 20 monitors the timer to determine whether or not the cool-down has ended, that is, whether or not a predetermined time has elapsed (step S208). If the cool-down has not ended (step S208: NO), the control unit 20 continues to wait for the end. If the cool-down is completed (step S208: YES), 1 is subtracted from the second counter 20c (step S209). And the process at the time of power-off operation of the projector 1 is complete | finished, and it transfers to a standby state.

Here, the third warning screen will be described.
FIG. 7 is an explanatory diagram of a third warning screen.

  As shown in FIG. 7, a character string “Do you want to turn off the power? OFF: Press the power button” is displayed as an OSD image at the top of the third warning screen M3. In the center of the third warning screen M3, a character string “AC power is cut off before the last cooldown is finished. Please do not cut off until the cooldown is finished” is displayed as an OSD image. Is done.

  As described above, when the power of the projector 1 is turned off, if the value of the second counter 20c is larger than the previous value of the second counter, the power is cut off during the previous cool-down (second cooling state). Judging and prompting the user not to cut off the power from the AC power supply (commercial power supply) until the cool-down is completed.

  As described above, when the control unit 20 performs the process, the first counter 20a stores the number of times the power from the AC power source (commercial power source) is cut off while the light source 11 is turned on. The second counter 20c stores the number of times the power from the AC power source (commercial power source) is cut off during the cool-down. When the operation receiving unit 21 receives a predetermined operation, the projector 1 according to the present embodiment displays (projects) these numbers as a power-off number display screen. The predetermined operation refers to, for example, an operation of displaying a menu screen and selecting a predetermined item in the menu screen.

Here, the power shutdown count display screen will be described.
FIG. 8 is an explanatory diagram of a power shutdown count display screen.

  As shown in FIG. 8, on the power shut-off count display screen M4, a character string “AC power shut-off while the lamp is lit” is displayed as an OSD image, and below that “number of times” based on the value of the first counter 20a. Is displayed. In this embodiment, “twice” is set. Further below, a character string “AC power supply cut off during cool-down” is displayed as an OSD image, and below the “number of times” based on the value of the second counter 20c. In this embodiment, “3 times” is set.

According to the first embodiment described above, the following effects can be obtained.
(1) The projector 1 compares the first counter 20a with the previous value of the first counter, so that whether or not the power from the commercial power source is cut off in the state where the light source 11 is turned on, that is, the first cooling state. Can be determined. Further, by comparing the second counter 20c and the previous value of the second counter, it can be determined whether or not the power from the commercial power source is cut off in the cool-down state, that is, the second cooling state. . When the power is cut off, the projector 1 can project a warning screen corresponding to each and notify the user of the warning screen. Accordingly, the user can recognize an error in the operation method of the projector 1 and can improve the operation method. Further, when an AV system or the like is constructed using the projector 1, it is possible to improve the control method and power management method of the AV system.

  (2) The projector 1 can count the number of times power is cut off by the first counter 20a and the second counter 20c. Then, the number of times can be projected as a power-off number display screen M4. This is beneficial because it enables a user (particularly a user who maintains or repairs the projector) to recognize the power cutoff status of the projector 1.

  (3) When the projector 1 accepts the power-on operation, the projector 1 has previously determined whether or not the power from the commercial power source has been cut off in the state where the light source 11 is turned on, and has cooled down last time. It is determined whether or not power from the commercial power source is cut off in the state. If the power is cut off in any state, a corresponding warning screen is projected. This is beneficial because the user can recognize at the time of power-on operation that the power was interrupted last time when the light source 11 was turned on or during cool-down.

  (4) When the projector 1 receives the power-off operation, the projector 1 determines whether or not the power from the commercial power source has been cut off in the previous cool-down state. Then, if the power from the commercial power source is cut off, the third warning screen M3 is projected. Thereby, the user can recognize at the time of power-off operation that the power was cut off in the cool-down state last time. Further, in the third warning screen M3, the user recognizes that the power should not be cut off during the cool-down in order to prompt the user not to cut off the AC power (commercial power) until the cool-down is completed. It is possible and beneficial.

(Second Embodiment)
In the second embodiment, a projector will be described that uses the first flag and the second flag to determine that power from a commercial power source (external power source) has been cut off.

  The external appearance of the projector of the second embodiment is the same as that of the first embodiment shown in FIGS. Therefore, explanation is omitted.

Next, a circuit configuration of the projector according to the second embodiment will be described.
FIG. 9 is a block diagram illustrating a circuit configuration of the projector 100 according to the second embodiment.
As shown in FIG. 9, the difference between the circuit configuration of the projector 100 and the circuit configuration of the projector 1 of the first embodiment is only the control unit. Hereinafter, differences will be described.

  Instead of the first counter 20a, the first counter previous value storage unit 20b, the second counter 20c, and the second counter previous value storage unit 20d included in the control unit 20 of the projector 1, the control unit 20s of the projector 100 is provided. A first flag setting unit 20e, a third counter 20f, a second flag setting unit 20g, and a fourth counter 20h are provided. The first flag setting unit 20e, the third counter 20f, the second flag setting unit 20g, and the fourth counter 20h are configured by a writable nonvolatile memory.

  A first flag is set in the first flag setting unit 20e. The first flag is set when the light source 11 is turned on, that is, when the first cooling state in which the inside of the housing 2 is cooled, and is cleared when the first cooling state ends. A second flag is set in the second flag setting unit 20g. The second flag is set at the start of the second cooling state, which is a cool-down state, and is cleared at the end of the second cooling state. The third counter 20f adds 1 when the first flag is not cleared. The fourth counter 20h adds 1 when the second flag is not cleared.

  The initial value of the first flag is 0 (clear). The initial value of the third counter 20f is zero. The initial value of the second flag is 0 (clear). The initial value of the fourth counter 20h is zero. Here, the initial value indicates a value at the time of shipment of the projector 100.

Next, processing when the projector 100 shifts to the power-on state will be described.
FIG. 10 is a flowchart of processing when the projector 100 shifts to the power-on state.

  When a power-on operation is performed using the power key, the control unit 20s instructs the light source control unit 25 to turn on the light source 11 (step S301). The control unit 20s instructs the cooling control unit 23 to start cooling by the cooling fan 24 (first cooling state) (step S302). Next, the control unit 20s determines whether or not the first flag is set (step S303). The control unit 20s at this time corresponds to a first determination unit. When the first flag is set (step S303: YES), the control unit 20s instructs the OSD processing unit 33 to project the first warning screen M1 (see FIG. 5) (step S304). Then, 1 is added to the third counter 20f (step S305). Then, the process proceeds to step S306. When the first flag is not set (that is, when it is cleared) (step S303: NO), the control unit 20s proceeds to step S306 without executing steps S304 and S305.

  In step S306, the control unit 20s sets the first flag (step S306). Then, the control unit 20s determines whether or not the second flag is set (step S307). The control unit 20s at this time corresponds to a second determination unit. If the second flag is set (step S307: YES), the control unit 20s instructs the OSD processing unit 33 to project the second warning screen M2 (see FIG. 5) (step S308). Then, the control unit 20s adds 1 to the fourth counter 20h (step S309). And the process at the time of the projector 100 shifting to a power-on state is complete | finished.

  When the second flag is not set (that is, when it is cleared) (step S307: NO), the control unit 20s does not execute step S308 and step S309, and the projector 100 shifts to the power-on state. The processing when performing is terminated. Here, the control unit 20s that performs the processing from step S303 to step S309 corresponds to a warning projection control unit.

  As described above, when the power is turned on, when the first flag is set, the projector 100 is assumed that the power from the AC power source (commercial power source) is cut off during the previous lighting of the light source 11. Judgment is made and the user is notified of this. If the second flag is set, it is determined that the power from the AC power source (commercial power source) has been cut off during the previous cool-down, and the user is informed accordingly.

Next, a process when the projector 100 is turned off will be described.
FIG. 11 is a flowchart of processing when the power-off operation of the projector 100 is performed.

  When the power-off operation is performed with the power key, the control unit 20s determines whether or not the second flag is set (step S401). The control unit 20s at this time corresponds to a second determination unit. When the second flag is set (step S401: YES), the control unit 20s instructs the OSD processing unit 33 to project the third warning screen M3 (see FIG. 7) (step S402). When the power key (power button) is pressed, the process proceeds to step S403. When the second flag is not set (that is, when it is cleared) (step S401: NO), the control unit 20s proceeds to step S403 without executing step S402. Here, the control unit 20s that performs the processing from step S401 to step S402 corresponds to a warning projection control unit.

  In step S403, the control unit 20s instructs the light source control unit 25 to turn off the light source 11 (step S403). Next, the control unit 20s clears the first flag (step S404). Then, the control unit 20s issues an instruction to the cooling control unit 23, ends the first cooling state, and starts cool-down (second cooling state) (step S405). And control part 20s sets the 2nd flag (Step S406).

  The control unit 20s monitors the timer to determine whether or not the cool-down has ended (step S407). If the cool-down has not ended (step S407: NO), the control unit 20s continues to wait for the end. If the cool-down is completed (step S407: YES), the second flag is cleared (step S408). Then, the process when the power-off operation of the projector 100 is performed is terminated, and the process shifts to the standby state.

  As described above, when the power-off operation is performed, if the second flag is set, the projector 100 determines that the power from the AC power source (commercial power source) is cut off during the previous cool-down, The user is encouraged not to cut off the AC power (commercial power) until the cool-down is completed.

  Further, as described above, the control unit 20s performs the process, and the third counter 20f stores the number of times the power from the AC power source (commercial power source) is cut off while the light source 11 is turned on. The fourth counter 20h stores the number of times the power from the AC power source (commercial power source) is cut off during the cool-down. Similarly to the projector 1 of the first embodiment, when the operation receiving unit 21 receives a predetermined operation, the projector 100 according to the present embodiment displays (projects) these times as a power-off number display screen M4.

According to the second embodiment described above, the same effects as the effects (3) and (4) of the first embodiment can be achieved. In addition, the following effects can be obtained.
(1) By determining the state of the first flag, the projector 100 can determine whether or not the power from the commercial power source is cut off in the state where the light source 11 is turned on, that is, in the first cooling state. . Further, by determining the state of the second flag, it is possible to determine whether or not the power from the commercial power source is cut off in the cool-down state, that is, in the second cooling state. When the power is cut off, the projector 100 can project a warning screen corresponding to each and notify the user of the warning screen. Thereby, the user can recognize an error in the operation method of the projector 100 and can improve the operation method. Further, when an AV system or the like is constructed using the projector 100, it is possible to improve the control method and power management method of the AV system.

  (2) The projector 100 can count the number of times power is cut off by the third counter 20f and the fourth counter 20h. The number of times can be displayed as a power-off number display screen M4. This is beneficial because a user (particularly a user who maintains or repairs the projector) can recognize the power cutoff status of the projector 100.

  In addition, it is not limited to embodiment mentioned above, It is possible to implement by adding various change, improvement, etc. A modification will be described below.

  (Modification 1) In the above embodiment, the power-on operation, the power-off operation, and other key operations are performed by the power key provided in the operation accepting unit 21, but the communication unit ( (Not shown), and a power-on operation signal, a power-off operation signal, and other key operation signals may be received by communication from an external electronic device (not shown).

  (Modification 2) In the above embodiment, the light source 11 is constituted by the discharge-type light source lamp 11a. However, an LED (Light Emitting Diode) light source, a solid light source such as a laser, and other light sources can also be used. .

  (Modification 3) In the embodiment described above, the projector 1 (100) performs the cool-down for a predetermined time (for example, 30 seconds), but is not limited thereto. For example, the temperature inside the housing 2 may be detected by the temperature sensor 22 during the cool-down, and the cool-down may be terminated when the temperature reaches a predetermined temperature.

  (Modification 4) In the above embodiment, the projector 1 (100) is described as an example. However, the inside of the housing 2 is cooled when the light source 11 is turned on, and then cooled after the light source 11 is turned off. The present invention can be applied to any image display device having a function of continuing the operation for a while. For example, the present invention can be applied to a rear projector or the like that is integrally provided with a transmissive screen.

  (Modification 5) In the above-described embodiment, the transmissive liquid crystal light valves 12R, 12G, and 12B are used as the light modulators. However, a reflective light modulator such as a reflective liquid crystal light valve may be used. Is possible. In addition, it is possible to use a micromirror array device that modulates light emitted from a light source by controlling the emission direction of incident light for each micromirror as a pixel.

  DESCRIPTION OF SYMBOLS 1,100 ... Projector, 2 ... Housing | casing, 3a ... Intake port, 3b ... Exhaust port, 10 ... Image projection part, 11 ... Light source, 11a ... Light source lamp, 11b ... Reflector, 12R, 12G, 12B ... Liquid crystal light valve, DESCRIPTION OF SYMBOLS 13 ... Projection lens, 14 ... Light valve drive part, 20, 20s ... Control part, 20a ... 1st counter, 20b ... 1st counter last time value memory | storage part, 20c ... 2nd counter, 20d ... 2nd counter last time value memory part 20e ... first flag setting unit, 20f ... third counter, 20g ... second flag setting unit, 20h ... fourth counter, 21 ... operation receiving unit, 22 ... temperature sensor, 23 ... cooling control unit, 24 ... cooling fan , 25 ... light source control unit, 26 ... power supply circuit, 27 ... power supply terminal, 31 ... image information input unit, 31a ... input terminal, 32 ... image processing unit, 33 ... OSD processing unit 33a ... OSD memory.

Claims (8)

A projector having an image projection unit that modulates and projects light emitted from a light source, a housing that houses the image projection unit, and a cooling unit that cools the inside of the housing,
A cooling control unit that switches between a first cooling state in which the cooling unit performs cooling when the light source is turned on and a second cooling state in which the cooling unit continues the cooling for a while after the light source is turned off; ,
A first determination unit that determines whether or not power from an external power source is interrupted in the first cooling state during a previous operation;
A second determination unit configured to determine whether power from the external power source is interrupted in the second cooling state during a previous operation;
When the first determination unit determines that the power from the external power source has been cut off during the previous operation, the first determination unit causes the image projection unit to project a first warning screen, and the second determination unit A warning projection control unit that causes the image projection unit to project a second warning screen when it is determined that power from the external power source has been cut off during a previous operation;
A projector comprising: The projector according to claim 1,
An operation receiving unit that receives an operation for instructing to turn on or off the light source;
The first determination unit and the second determination unit make a determination when the operation reception unit receives an operation for turning on the light source,
The warning projection control unit causes the image projection unit to project the first warning screen or the second warning screen based on the determination results by the first determination unit and the second determination unit. Projector. The projector according to claim 1 or 2,
An operation receiving unit that receives an operation for instructing to turn on or off the light source;
The second determination unit performs a determination when the operation reception unit receives an operation for turning off the light source,
The warning projection control unit causes the image projection unit to project a third warning screen when it is determined that the power from the external power source has been cut off in the previous second cooling state. . The projector according to claim 3,
The projector according to claim 3, wherein the third warning screen includes a display prompting the user not to cut off the power from the external power source during the second cooling state. A projector according to any one of claims 1 to 4,
A first counter that is added at the start of the first cooling state and subtracted at the end of the first cooling state;
A second counter that is added at the start of the second cooling state and subtracted at the end of the second cooling state;
Have
The first determination unit determines whether power from the external power source is interrupted in the first cooling state based on a value of the first counter,
The projector according to claim 2, wherein the second determination unit determines whether power from the external power source is cut off in the second cooling state based on a value of the second counter. A projector according to any one of claims 1 to 4,
A first flag setting unit that is set at the start of the first cooling state and that sets a first flag that is cleared at the end of the first cooling state;
A second flag setting unit that is set at the start of the second cooling state and that sets a second flag that is cleared at the end of the second cooling state;
Have
The first determination unit determines whether power from the external power source is interrupted in the first cooling state based on a value of the first flag,
The projector according to claim 2, wherein the second determination unit determines whether power from the external power source is cut off in the second cooling state based on a value of the second flag. The projector according to claim 6, wherein
A third counter to be added if the first flag is not cleared;
A fourth counter to be added when the second flag is not cleared;
Further comprising
The first determination unit counts the number of times the power from the external power source is cut off in the first cooling state according to the value of the third counter,
The projector according to claim 2, wherein the second determination unit counts the number of times power from the external power source is cut off in the second cooling state according to a value of the fourth counter. A method for controlling a projector, comprising: an image projection unit that modulates and projects light emitted from a light source; a housing that houses the image projection unit; and a cooling unit that cools the interior of the housing. ,
A cooling control step of switching between a first cooling state in which the cooling unit performs cooling when the light source is turned on and a second cooling state in which the cooling unit continues the cooling for a while after the light source is turned off; ,
A first determination step of determining whether or not power from an external power source is interrupted in the first cooling state during a previous operation;
A second determination step of determining whether or not power from the external power source is interrupted in the second cooling state during the previous operation;
When it is determined by the first determination step that the power from the external power source has been cut off during the previous operation, the image projection unit projects a first warning screen, and the second determination step A warning projection control step for causing the image projection unit to project a second warning screen when it is determined that power from the external power source has been cut off during a previous operation;
A projector control method comprising:

Images