JP2011160315A - Projector, and image projection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector and the like in which trapezoidal correction can be performed with a simple structure with a cost increase suppressed and adjustment work of the trapezoidal correction can be simplified after canceling the interruption of projection. <P>SOLUTION: In the case where operation of a first specific key is detected by a key input processing section 13 as a second detection section and the cancellation of a suspending operation is then detected by the key input processing section 13 or a shutter detecting section 18 as a first detection section, a control section 11 causes a video projection section to display a test pattern from which the state of trapezoidal correction can be determined. Accordingly, an image corresponding to an input signal can be prevented from being immediately projected by canceling the suspending operation and after preparation is completed by making the trapezoidal correction proper in accordance with the test pattern beforehand, the image corresponding to the input signal can be projected. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a projector capable of a pause operation for interrupting image projection, and an image projection method using the projector.

  As a projector, in order to reduce image distortion due to oblique projection, it is known to correct a trapezoidal distortion of a display image by forming an image in a part of an image display area of an image forming panel. The keystone correction key can be used to increase or decrease the trapezoidal distortion correction amount, that is, the trapezoidal correction amount. In order to improve the function of the above-described manual adjustment type projector, there is a type in which the installation angle of the projector is detected and keystone correction is automatically performed according to the installation angle (see Patent Document 1).

  As another projector, there is a projector that has a slide type lens shutter and controls the driving state of the liquid crystal panel to project a black image in order to suppress the heat generation of the lens shutter when the lens shutter is closed. (See Patent Document 2). In such a projector, since the display can be temporarily interrupted by temporarily closing the lens shutter, the screen can be temporarily hidden when switching presentations, for example.

JP 2003-283963 A JP 2007-240551 A

  However, the projector as disclosed in Patent Document 1 requires an installation angle detection device such as an angle sensor, which complicates the device and increases the cost.

  If the projector as in Patent Document 2 is a manual adjustment type projector that uses the keystone correction key, when the lens shutter is closed and the installation angle of the projector is changed, the keystone correction is set appropriately. Is not easy. In other words, when the lens shutter is closed, no image is projected onto the screen, so that the keystone correction cannot be optimized. In this type of projector, when the lens shutter is opened to optimize the keystone correction, the black display is canceled, and an unintended image, for example, a screen that is not ready for presentation, is projected.

  Therefore, the present invention provides a projector that can perform keystone correction with a simple structure that suppresses an increase in cost, and that can simplify the adjustment work of trapezoid correction after cancellation of projection interruption, and an image projection method using the projector. Objective.

  In order to solve the above problems, a projector according to the present invention detects a video projection unit that projects an image, a first detection unit that detects cancellation of a pause operation of the video projection unit, and an operation of a predetermined key among operation keys. And a second pattern of a predetermined pattern that makes it possible to determine the state of the keystone correction when the first detection unit detects the release of the pause operation after the second detection unit detects the operation of the predetermined key. And a control unit that causes the video projection unit to perform display.

  According to the projector described above, the keystone correction is performed when the control unit detects the release of the pause operation after the first detection unit detects the operation of the predetermined key (first specific key) by the second detection unit. Since the video projection unit displays a predetermined pattern that makes it possible to determine the state of the image, it is possible to avoid that the image corresponding to the input signal is immediately projected by canceling the pause operation, and the keystone correction is performed in advance using the predetermined pattern. The image corresponding to the input signal can be projected after the preparation of the actual projection is completed by optimizing the above.

  In a specific aspect of the invention, in the projector, a closed position that blocks light projected from the projection lens provided in the video projection unit and an open position that does not block light projected from the projection lens can be selected. A shutter is further provided, and the first detection unit detects that the shutter is changed from the closed position to the open position as cancellation of the pause operation. In this case, it is possible to perform a pause operation in which the operation of the video projection unit is paused by setting the shutter to the closed position, and the pause operation is canceled by setting the shutter to the open position. Furthermore, when a predetermined key is operated before the shutter is opened, a predetermined pattern that allows the image projection unit to determine the trapezoidal correction state can be displayed by opening the shutter. it can.

  In another aspect of the present invention, the first detection unit detects that the mute key among the operation keys is operated as release of the pause operation. In this case, by operating the mute key first, it is possible to perform a pause operation that puts the operation of the video projection unit into a pause state. By operating the mute key again, the pause operation is canceled. Further, when the predetermined key is operated before the mute key is operated again, the predetermined pattern that makes it possible to determine the keystone correction state can be displayed on the video projection unit by operating the mute key again. it can.

  In still another aspect of the present invention, the predetermined pattern is a test pattern including a geometric figure. In this case, it is possible to easily and quickly determine whether or not the keystone correction amount is appropriate, and manual keystone correction work can be simplified.

  In yet another aspect of the present invention, the control unit is configured to control the video projection unit based on an input signal when any one of the operation keys is operated while the video projection unit displays a predetermined pattern. Have the image projected. In this case, by operating any one key (second specific key) included in the operation keys, a predetermined pattern for determining the keystone correction state can be switched to an image corresponding to a normal input signal and projected. .

  In yet another aspect of the present invention, a timer is further provided for measuring a standing time after the operation of the predetermined key is detected by the second detection unit. When the timer reaches a predetermined time, an input signal is sent to the video projection unit. The image projection based on is performed. In this case, the detection of the predetermined key operation by the second detection unit is canceled in a predetermined time, so that the normal operation can be restored if the user leaves the user without performing any specific operation.

  In yet another aspect of the present invention, the image processing apparatus further includes a trapezoid correction unit that performs keystone correction on an image to be projected on the video projection unit, and the control unit operates the operation key when displaying the predetermined pattern on the video projection unit. The keystone correction amount by the keystone correction unit can be adjusted by reading any one or more operations included in the keystone correction unit. In this case, the keystone correction amount can be optimized by operating the keystone correction key before projecting the image corresponding to the input signal.

  In still another aspect of the present invention, the second detection unit detects an operation of a menu key that displays a menu screen for setting change as a predetermined key.

  In yet another aspect of the present invention, there is provided an image projection method by a projector including a video projection unit that projects an image, and an operation of a predetermined key among operation keys in a state in which pause control is performed to pause the operation of the video projection unit. When the release of the pause operation is detected, the video projection unit is caused to display a predetermined pattern that can determine the trapezoidal correction state.

  According to the above image projection method, when the operation of the predetermined key is detected in the state where the pause control is applied, the display of the predetermined pattern that makes it possible to determine the state of the keystone correction when the release of the pause operation is detected. By releasing the pause operation, the image corresponding to the input signal can be prevented from being projected immediately, and preparation for the actual projection can be performed by optimizing the keystone correction using the predetermined pattern in advance. After completion of this, an image corresponding to the input signal can be projected.

It is a figure which shows the external appearance of the projector of embodiment. It is a block diagram which shows the structure of the projector of embodiment. It is a figure which illustrates the key element which comprises a key operation part. It is a figure explaining the flow of the process performed with the projector of embodiment. It is a figure explaining the flow of the process performed with the projector of embodiment. (A) And (B) is a figure which illustrates the test pattern projected on a screen by a video projection part.

  Hereinafter, a projector according to an embodiment of the invention will be described in detail with reference to the drawings.

[A. (Appearance structure of projector)
As shown in FIG. 1, almost the entire projector 10 is accommodated in a case 41. A part of the top panel 41a of the case 41 is provided with a key operation unit 28 for a user to input an instruction. A recess 41c is provided in a part of the front panel 41b of the case 41, and a projection lens 42 is disposed in the recess 41c so as to expose the projection side portion 42a. A shutter 43 is assembled to the front panel 41b so as to be openable and closable. That is, the shutter 43 is slidable in the lateral direction along the front panel 41b by a slide mechanism (not shown), and the projection 43 is exposed so as not to block the projection light by exposing the projection side portion 42a to the outside. Selectively move between a position (shown with solid and dotted lines) and a closed position (shown with a dashed line) that blocks projection light by covering the projection side portion 42a of the projection lens 42 arranged in the recess 41c. It is possible. A pair of sensors 44a and 44b are embedded in the front panel 41b, and based on detection signals from these sensors 44a and 44b, the shutter 43 is in the open position or in the open state, or the shutter 43 is in the closed position. It can be judged whether it is in a closed state.

[B. (Internal structure of projector)
As shown in FIG. 2, the projector 10 includes a control unit 11, a storage unit 12, a key input processing unit 13, an input selection unit 14, an image processing unit 15, and a video projection unit 17 as a main body 10a. The shutter detection unit 18, the communication unit 19, and the power supply unit 22 are provided.

  The control unit 11 controls the entire function of the projector 10. That is, the control unit 11 is communicably connected to the storage unit 12, the key input processing unit 13, the input selection unit 14, the image processing unit 15, the shutter detection unit 18, the communication unit 19, the power supply unit 22, and the like. Information is taken in from these parts, or a control signal or the like is sent to these parts to control the operation state. In particular, the control unit 11 includes a mute instruction unit 11a, a test pattern instruction unit 11b, a timer function unit 11c, a keystone correction management unit 11d, and the like. Details of these functions will be described later.

  The storage unit 12 includes a ROM 12a, a RAM 12b, a nonvolatile memory 12c, and the like, and holds programs, data, and the like necessary for operating the projector 10. This data includes, for example, information on the keystone correction performed by the keystone correction unit 15a of the image processing unit 15, specifically, the keystone correction amount at the end of the previous operation before the current activation, and the keystone correction before the shutter 43 is closed. The amount is included. Such information on keystone correction is stored in a rewritable manner in, for example, the nonvolatile memory 12c of the storage unit 12. Although details will be described later, the storage unit 12 appropriately associates the opening / closing operation of the shutter 43 and the operation history of the key operation unit 28 and reflects them in a specific operation such as a test pattern display described later of the projector 10. The operation of the operation unit 28 is temporarily stored. Furthermore, the storage unit 12 can hold a signal processing state such as the type of input signal and the operation mode at the current time. Here, the type of input signal means, for example, an image signal from a computer or a video signal from a digital player. In addition, the storage unit 12 can also hold image data corresponding to a projection image to be projected on the video projection unit 17.

  The key input processing unit 13 is an input unit for inputting a user instruction, and includes a key operation unit 28 including a set of operation keys. The key input processing unit 13 can be accompanied by a display as a UI. A remote control light receiving unit 25 is provided along with the key input processing unit 13 so that a command signal can be received remotely from the remote control 26 by radio. As illustrated in FIG. 3, the key operation unit 28 includes a power key 28a, an input switching key 28b, a menu key 28c, a mute key 28d, an escape key 28e, and four triangular keys 29a, 29b, 29c indicating directions. , 29d, enter key 29e, two keystone correction keys 29f, 29g, zoom key 29h, etc. are provided in a suitable arrangement as a set of operation keys. These operation keys 28a, 28b, 28c, 28d, 28e, 29a, 29b, 29c, 29d, 29e, 29f, 29g, and 29h can be provided not only on the key operation unit 28 but also on the remote control 26. The number of operation keys provided in the key operation unit 28 can also be reduced. The menu key 28c is used when displaying a menu screen for changing various setting states of the projector 10. The input switching key 28b is used when the input selection unit 14 switches the input signal. Of the two keystone correction keys 29f and 29g, the first keystone correction key 29f is for shifting to the upper keystone correction and strengthening the upper keystone correction, and the second keystone correction key 29g is on the lower side. This is to shift to the trapezoidal correction and strengthen the lower keystone correction. The keystone correction keys 29f and 29g can be provided with a function of a keystone correction confirmation button that allows the keystone correction amount to be displayed and confirmed by projection when pressed for a short time.

  The input selection unit 14 is connected to the connector 31. A plurality of image output devices (not shown) such as a computer, a disk player and the like can be connected to the connector 31 at the same time. The input selection unit 14 operates under the control of the control unit 11, receives an input signal (that is, an image signal) from any one of a plurality of image output devices connected to the connector 31, and sends it to the image processing unit 15. Output.

  The image processing unit 15 can perform various corrections including gradation correction, color correction, keystone correction, magnification correction, and the like on an image signal or image data input from the outside via the input selection unit 14 or the communication unit 19. it can. These gradation correction, color correction, trapezoidal correction, magnification correction, and the like can be changed under the control of the control unit 11, and the user uses the key input processing unit 13 to change the contents of the image processing unit 15. The image processing state can be switched, and settings such as gradation correction, color correction, keystone correction, and magnification correction can be adjusted as appropriate. In particular, the image processing unit 15 can form an image corresponding to the input signal only on a part of the liquid crystal panel (trapezoid region) of the video projection unit 17 by the trapezoid correction unit 15a, and is projected onto a screen (not shown). As a result, the trapezoidal distortion of the image can be corrected. Such a trapezoidal correction amount can be adjusted by operating the keystone correction keys 29f and 29g of the key operation unit 28, and a substantially rectangular image can be projected on the screen. Further, the image processing unit 15 replaces or superimposes an external image signal or the like based on a command from the control unit 11 with an image signal for displaying character information or the like from the image data extracted from the storage unit 12. Can be generated.

  The video projection unit 17 includes a liquid crystal panel drive unit 17 a that drives the liquid crystal panels for each color of RGB based on the image signal after image processing output from the image processing unit 15. In addition, the video projection unit 17 includes a lamp driving circuit 17 c that turns on a lamp provided in the lighting device in a desired state. The lamp driving circuit 17 c operates under the control of the control unit 11. Although not described in detail, the video projection unit 17 includes, as an optical system, an illumination device, a liquid crystal panel for each color, a synthesis prism, and the like in addition to the projection lens 42 shown in FIG. A color image is displayed on a screen (not shown) by combining and projecting the light transmitted through the liquid crystal light valves for the respective colors. Here, although not shown in FIG. 2, the projection lens 42 shown in FIG. 1 projects an image modulated by the liquid crystal panel for each color and synthesized by the synthesis prism at a desired magnification. Note that the optical system of the video projection unit 17 is not limited to the liquid crystal system, but can use various systems such as a digital micromirror device system, an LCOS system, a GLV system, and a CRT system. Moreover, although the projector 10 which projects using a lamp as a light source was illustrated, it can apply also to the projector which projects using an LED light source, a laser light source, etc. as a light source.

  The shutter detection unit 18 operates under the control of the control unit 11, and can detect whether or not the shutter 43 is in the open position and in the open state based on the detection signal of the sensor 44a. Based on this detection signal, it is possible to detect whether or not the shutter 43 is in the closed position.

  The communication unit 19 is an interface circuit that enables communication. The communication unit 19 can be a wireless interface circuit that enables communication in an ad hoc mode of a wireless LAN, for example. In this case, peer-to-peer connection can be performed with a computer or other network connection type device. . The communication unit 19 may be a wired interface circuit connected to a wired LAN or the like.

  The power supply unit 22 operates under the control of the control unit 11 and supplies power to each unit of the projector 10.

[C. Projector operation)
Hereinafter, an example of a projection operation by the projector 10 illustrated in FIG. 1 and the like will be described with reference to FIGS.

  When the instruction signal detected by the key input processing unit 13 requests activation, the control unit 11 of the projector 10 starts processing described below. Specifically, when the projection operation of the projector 10 is in a stopped state, when the user presses the power key 28a of the key operation unit 28, display processing for projecting an image is started.

  First, the control unit 11 operates the lamp driving circuit 17c of the video projection unit 17 to execute a sequence for lighting the lamp of the illumination device, and appropriately operates the image processing unit 15 to output an image signal or a driving signal. This causes the video projection unit 17 to start projecting an image (step S1). At this time, the control unit 11 refers to the non-volatile memory 12c of the storage unit 12 to restore the signal processing state in the main body 10a to the state at the end of the previous operation. Specifically, the input terminal selected by the input selection unit 14, the operation mode, the keystone correction amount, and the like are set to a state immediately before the lamp is turned off, that is, before the projection operation is stopped, and the video projection unit via the image processing unit 15 17 starts image projection.

  Next, the control unit 11 checks the operation of the power key 28a of the key operation unit 28 provided in the key input processing unit 13, and determines whether or not there is an instruction to end projection from the user (step S2). When there is no instruction to end projection from the user (step S2: N), the control unit 11 determines whether or not a pause operation has been performed by the user (step S3). Here, the pause operation is a screen mute start condition to be described later, and means that the user starts the closing operation of the shutter 43 or the user presses the mute key 28d of the key operation unit 28. Specifically, for example, when the shutter detection unit 18 detects that the shutter 43 starts to be displaced from the open position to the closed position based on the output of the sensor 44a or the like, the control unit 11 performs a pause operation. Judge that

  When the control unit 11 determines that the user has not performed the pause operation (step S3: N), the control unit 11 returns to step S2 and determines whether or not the user has instructed to end the projection. On the other hand, when it is determined that a pause operation has been performed by the user (step S3: Y), the control unit 11 sets the pattern flag stored in the RAM 12b or the nonvolatile memory 12c of the storage unit 12 to OFF (step S11). Here, the pattern flag is for recording the operation of the first specific key in the mute state, and means that the test pattern is displayed on the video projection unit 17 when the screen mute is released. When the pattern flag is ON, the control unit 11 prepares in advance via the image processing unit 15 without immediately projecting the image corresponding to the input signal even if the screen mute corresponding to the pause operation is released thereafter. A test pattern for keystone correction is projected on the video projection unit 17.

  Next, the control unit 11 sets the projection screen to mute, which is a paused state, as the mute instruction unit 11a (step S12). Specifically, the control signal is output to the image processing unit 15 to perform black display image processing regardless of the input signal, and the video projection unit 17 projects a black image. Due to the screen mute state, that is, the pause state, the image projection is temporarily stopped regardless of the input signal selected by the input selection unit 14. Note that the screen mute state is not limited to the black image projection as described above, but includes a case where a dark image with low illuminance is projected, and a static or dynamic pattern unrelated to the input signal in the image. May be included. When performing the above-mentioned screen mute, the control unit 11 temporarily stores the signal processing state such as the type of the input signal and the keystone correction amount in the RAM 12b, the nonvolatile memory 12c, and the like of the storage unit 12.

  Next, the control unit 11 determines whether or not the screen mute release operation has been performed by the user (step S13). Here, the screen mute release operation means the reverse operation of the pause operation detected in step S3. That is, the screen mute release operation means that the user moves the shutter 43 to the open position, or the user presses the mute key 28d again in the key operation unit 28 provided in the key input processing unit 13. Here, the shutter detection unit 18 that detects the opening of the shutter 43 and the key input processing unit 13 including the mute key 28d function as a first detection unit that detects the release of the pause operation. However, when the shutter 43 is not in the open position, there is no point in projecting an image, and therefore it is not assumed that the screen mute is not canceled even if the mute key 28d is pressed again. That is, the screen mute is canceled by the mute key 28d only when the shutter 43 is in the open position.

  When the control unit 11 determines that the screen mute release operation has not been performed by the user (step S13: N), the pattern flag described in step S11 is set with reference to the RAM 12b or the nonvolatile memory 12c of the storage unit 12. It is determined whether or not it is ON (step S14). When the pattern flag is OFF, the control unit 11 determines whether or not the user has operated the first specific key, that is, the predetermined key among the key operation units 28 provided in the key input processing unit 13 as the second detection unit. It detects (step S15). Here, the first specific key is a key for requesting that a test pattern for keystone correction be projected without projecting an image corresponding to the input signal even when the screen mute is canceled. Of these, for example, the menu key 28c, the escape key 28e, and the like correspond to this.

  When the control unit 11 detects that the user has operated the first specific key of the key operation unit 28 provided in the key input processing unit 13 (step S15: Y), the RAM 12b of the storage unit 12 or the nonvolatile memory 12c In step S16, the pattern flag is rewritten to ON, and the timer function unit 11c starts timer counting (step S16). Note that if the control unit 11 does not detect that the user has operated the first specific key in the key operation unit 28 (step S15: N), the control unit 11 returns to step S13, and already described steps S13 to S13. The detection or determination in S15 is performed.

  After the timer is started in step S16, the control unit 11 determines whether or not the measurement of the timer has reached a predetermined time (step S17). Here, the predetermined time is stored in advance in the nonvolatile memory 12c of the storage unit 12, and is a criterion for determining whether or not the leaving time after the operation of the first specific key is long. In a specific operation example, for example, 10 seconds is set as the predetermined time, but the present invention is not limited to this, and an appropriate time can be set, and the user can change the predetermined time. Even if it is determined in step S14 that the pattern flag is ON, it is assumed that the timer has already been started in step S16, and the process skips steps S15 and S16 to proceed to step S17, where the timer measurement is performed in advance. It is determined whether time has been reached.

  When it is determined that the timer measurement has reached the predetermined time (step S17: Y), the control unit 11 rewrites the pattern flag to OFF and counts the timer in the RAM 12b or the nonvolatile memory 12c of the storage unit 12. Stop (step S18).

  On the other hand, when it is determined that the measurement of the timer has not reached the predetermined time (step S17: N), the control unit 11 returns to step S13 and performs detection, determination, or processing of steps S13 to S16. That is, the control unit 11 determines whether or not the user has performed a screen mute release operation (step S13), whether or not the user has operated the first specific key of the key input processing unit 13 (step S15), and the like. If the operation of the first specific key is detected in a state where the screen mute is not released, and the screen mute is not released even after a predetermined time has elapsed (step S17: Y), the pattern flag is turned off. Is done. That is, when the user leaves the camera for a predetermined time without any particular operation, the mode for resuming the projection operation by a test pattern described later in response to the detection of the first specific key is canceled, and the normal operation mode can be restored.

  When it is determined in step S13 that the user has performed the screen mute canceling operation, the control unit 11 cancels the screen mute setting (step S21). Specifically, a control signal is output to the image processing unit 15 to interrupt the black display image processing.

  Thereafter, the control unit 11 refers to the RAM 12b or the nonvolatile memory 12c of the storage unit 12 to determine whether or not the pattern flag is ON (step S22). When the pattern flag is ON, the control unit 11 causes the video projection unit 17 to project the test pattern via the image processing unit 15 as the test pattern instruction unit 11b (step S23).

  FIG. 6A is a diagram illustrating a test pattern PA projected by the video projection unit 17. The image of the test pattern PA projected on the screen SC is a trapezoid spreading upward due to trapezoidal distortion. In the illustrated example, the projector 10 is arranged considerably below the screen SC, and projection is performed such that the projector 10 is obliquely incident on the screen SC at a large angle. It has spread. The illustrated test pattern is merely an example, and the test pattern PA can include various geometric figures. Further, various color patterns can be included in the test pattern PA.

  Next, the control unit 11 reads the image data with reference to the storage unit 12, and the image projection unit 17 through the image processing unit 15 shows, for example, a part of the test pattern PA as shown in FIG. In this way, a display KD that informs that the keystone correction is being received is projected (step S24). The user can gradually change the keystone correction amount by operating the keystone correction keys 29f and 29g of the key operation unit 28 provided in the key input processing unit 13 while observing the test pattern. When detecting a change in the trapezoid correction amount by monitoring the key operation unit 28, the control unit 11 stores the changed trapezoid correction amount setting in the RAM 12b or the like as the trapezoid correction management unit 11d, and changes the trapezoid after the change by the user. The image processing unit 15 is caused to perform a keystone correction process corresponding to the correction amount setting (step S25). During the display of the test pattern PA, it is a kind of pause state in which the projection state can be confirmed, and the user can adjust the focus and the like. Further, the user can switch the input signal by the input selection unit 14 by operating the input switching key 28b.

  FIG. 6B corresponds to FIG. 6A and shows a test pattern PA after keystone correction. In this case, the trapezoidal distortion is corrected, and the test pattern PA on the screen SC is in a rectangular state.

  Next, the control unit 11 detects whether or not the user has operated the second specific key among the key operation units 28 provided in the key input processing unit 13 (step S26). Here, the second specific key is a key that requests to project an image corresponding to an input signal without projecting a trapezoidal correction test pattern, for example, the input switching key 28b of the key operation unit 28 or the escape key. The key 28e corresponds to this. If the second specific key of the key operation unit 28 provided in the key input processing unit 13 is not operated, the control unit 11 returns to step S25, and when the user changes the keystone correction amount, the changed keystone correction is performed. The image processing unit 15 is caused to perform trapezoidal correction processing corresponding to the amount.

  On the other hand, when the second specific key of the key operation unit 28 provided in the key input processing unit 13 is operated, the control unit 11 refers to the nonvolatile memory 12c of the storage unit 12 and the like and pauses in step S3. When it is determined that the operation has been performed or when the signal processing state such as the type of the input signal and the keystone correction amount stored at the time of changing the settings in steps S23 to S25 is read, video projection is performed via the image processing unit 15. The unit 17 is caused to resume image projection (step S27). Thereafter, the control unit 11 returns to step S2 and determines whether or not there is an instruction to end projection from the user.

  When the user gives an instruction to end projection in step S2 (step S2: Y), the control unit 11 stores the current signal processing state in the nonvolatile memory 12c of the storage unit 12 and stores the current signal processing state in the image processing unit 15. The operation is stopped, the operation of the lamp driving circuit 17c of the video projection unit 17 is stopped, and the lamp is turned off (step S31).

  As is apparent from the above description, according to the projector 10 of the present embodiment, after the control unit 11 detects the operation of the first specific key by the key input processing unit 13 as the second detection unit (step S15). : Y), when the release of the pause operation is detected by the key input processing unit 13 or the shutter detection unit 18 which is the first detection unit (step S13: Y), the test pattern PA that can determine the trapezoid correction state Is displayed on the video projection unit 17 (step S22: Y), so that the image corresponding to the input signal can be prevented from being projected immediately by canceling the pause operation, and the keystone correction is performed in advance by the test pattern PA. After preparation is completed by optimization or the like (step S25), an image corresponding to the input signal can be projected (step S27).

[Other modifications]
Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments, and can be implemented in various modes without departing from the gist thereof. Such modifications are also possible.

  In the above embodiment, the screen mute is started by the user starting the closing operation of the shutter 43 or by a pause operation such as pressing the mute key 28d of the key operation unit 28. However, the user closes the shutter 43. The screen mute can be started only when the operation is started. Further, the screen mute can be started only when the user presses the mute key 28d of the key operation unit 28.

  In the above embodiment, as the first specific key for determining whether or not it is necessary to rewrite the pattern flag to ON, for example, the menu key 28c or the escape key 28e among the key operation units 28 constituting the second detection unit is used. (See step S15). However, the key operation for rewriting the pattern flag to ON is not limited to the menu key 28c and the escape key 28e, but the operation of other keys constituting the second detection unit, specifically, the keystone correction keys 29f and 29g, etc. It can be an operation. When the keystone correction keys 29f and 29g are dedicated keys for adjusting the keystone correction amount and a keystone correction confirmation button is separately provided in the key operation unit 28, the operation of such a keystone correction confirmation button is performed by the pattern flag. Key operation for rewriting to ON.

  In the above embodiment, when the second specific key such as the input switching key 28b and the escape key 28e in the key operation unit 28 is operated in step S26, the image projection unit 17 resumes image projection. Even if the second specific key is not operated, the image projection unit 17 can resume image projection when a predetermined time or more has passed without the trapezoid correction amount being changed in step S25.

  Further, in the above embodiment, the upper keystone correction and the lower keystone correction can be performed by the trapezoid correction unit 15a of the image processing unit 15. However, the keystone correction can also be performed on the left and right by the trapezoid correction unit 15a. .

  In the above embodiment, the pattern flag is reset using a timer (step S18), but an operation in which the pattern flag is not reset after a certain period is also possible.

  In the above embodiment, a black image or a low-illuminance image is projected when the screen is muted. However, the lamp itself provided in the illumination device can be darkened via the lamp driving circuit 17c when the screen is muted.

  In the above embodiment, the trapezoid correction amount is stored in the storage unit 12 and the trapezoid correction state at the start of screen mute is reproduced when the screen mute is released. However, the trapezoid correction amount is set to zero when the screen mute is released. The correction process can also be canceled once.

  The key operation unit 28 that functions as the second detection unit or a part of the first detection unit or the second detection unit is not necessarily provided in the main body 10a, and the key operation unit 28 may be provided only in the remote control 26.

  In the above description, the projection amount of the projection side portion 42a of the projection lens 42 is not large. However, for example, in the case of the type in which the projection side portion 42a protrudes greatly, it is not easy to cover the projection side portion 42a with the shutter 43. The shutter 43 may be provided behind or inside the projection lens 42, that is, between the projection lens 42 and the combining prism, or in the projection lens 42.

DESCRIPTION OF SYMBOLS 10 ... Projector, 10a ... Main body, 11 ... Control part, 11a ... Mute instruction | indication part, 11b ... Test pattern instruction | indication part, 11c ... Timer function part, 11d ... Keystone correction management part, 12 ... Memory | storage part, 12c ... Nonvolatile memory, DESCRIPTION OF SYMBOLS 13 ... Key input process part (2nd detection part or 1st detection part and 2nd detection part), 14 ... Input selection part, 15 ... Image processing part, 15a ... Trapezoid correction part, 17 ... Image | video projection part, 17a ... Liquid crystal panel driving unit 18 ... Shutter detection unit (first detection unit) 25 ... Remote control light receiving unit 28 ... Key operation unit 28a ... Power key 28b ... Input switching key 28c ... Menu key (predetermined key) 28d ... mute key, 28e ... escape key (predetermined key), 29e ... confirm key, 29f, 29g ... keystone correction key (predetermined key), 4 ... Case, 41b ... front panel, 41c ... recess, 42 ... projection lens, 42a ... projection portion, 43 ... shutter, 44a, 44b ... Sensor, PA ... test pattern, SC ... Screen

Claims (9)

A video projection unit for projecting an image;
A first detection unit for detecting release of the pause operation of the video projection unit;
A second detector for detecting an operation of a predetermined key among the operation keys;
A display of a predetermined pattern that makes it possible to determine the state of trapezoid correction when the release of the pause operation is detected by the first detection unit after the operation of the predetermined key is detected by the second detection unit. A control unit for the video projection unit to perform,
A projector comprising: A shutter that can select a closed position that blocks light projected from a projection lens provided in the video projection unit and an open position that does not block light projected from the projection lens;
The projector according to claim 1, wherein the first detection unit detects that the shutter is changed from the closed position to the open position as release of the pause operation.   The projector according to claim 1, wherein the first detection unit detects that the mute key among the operation keys is operated as release of the pause operation.   The projector according to any one of claims 1 to 3, wherein the predetermined pattern is a test pattern including a geometric figure.   The control unit is configured to output an image based on an input signal to the video projection unit when any one or more of the operation keys are operated while the video projection unit displays the predetermined pattern. The projector according to any one of claims 1 to 4, wherein projection is performed. A timer for measuring a standing time after detecting the operation of the predetermined key by the second detection unit;
The projector according to claim 5, wherein when the measurement of the timer reaches a predetermined time, the video projection unit is caused to perform image projection based on an input signal. A trapezoid correction unit that performs keystone correction on the image projected on the video projection unit;
The control unit reads one or more operations included in the operation key and adjusts the trapezoid correction amount by the trapezoid correction unit when the video projection unit displays the predetermined pattern. The projector according to any one of claims 1 to 6, wherein the projector is made possible.   The projector according to claim 7, wherein the second detection unit detects an operation of a menu key that displays a menu screen for changing a setting as the predetermined key. An image projection method using a projector including a video projection unit for projecting an image,
When the operation of a predetermined key among the operation keys is detected in a state in which the pause control for pausing the operation of the video projection unit is applied, it is possible to determine the trapezoidal correction state when the release of the pause operation is detected. An image projection method comprising causing the video projection unit to display a predetermined pattern.

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