JP2016106260A - Projector and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector and a control method thereof capable of reliably indicating the intrusion of an object interfering with image light to a user.SOLUTION: Upon detecting an object interfering with image light, a projector 1 displays a message image. When a predetermined time (e.g., several seconds) has elapsed, a control unit 20 instructs an OSD processor 24 to change the display position of the alarming message image within a projected image.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a projector that projects image light and a control method thereof.

  When using a projector that projects image light, if an obstacle enters the projector in the vicinity of the projector so as to block the image light, the obstacle is likely to be irradiated with light and become hot, so that sufficient care must be taken. For this reason, Patent Document 1 proposes a projector including a sensor that detects an obstacle (foreign matter) that has entered an opening of a housing through which image light passes. When the projector detects the obstacle, it can display a warning by OSD (on-screen display).

JP 2007-34318 A

  However, in a situation where projection of an image is partially blocked by an obstacle, even if a warning display is performed, a part of the warning display may not be visible. As a result, the content of the warning may not be transmitted to the user, and appropriate countermeasures may be delayed. In particular, in a proximity projection type projector that projects image light by widening the angle with a concave mirror, the image light reflected by the concave mirror diverges after being condensed at a predetermined position, so an obstacle is located near the position where the light is condensed. When an obstacle enters, the temperature of the obstacle tends to rise rapidly, and an immediate countermeasure is required.

  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 is a projector that displays an image by widening and projecting image light at a reflection unit, and detects an obstacle that blocks the image light reflected by the reflection unit. A detection unit, a message display unit that displays a warning message in the image when the detection unit detects the obstacle, and a display position of the warning message in the image is changed as time passes. And a display position changing unit.

  According to this projector, the display position changing unit changes the display position of the warning message displayed when an obstacle is detected as the time elapses, so that a part of the projected image is hidden by the obstacle. Even in such a case, the possibility that the warning message can be visually recognized increases as the display position changes.

  Application Example 2 In the projector according to the application example, it is preferable that the message display unit displays the warning message when the detection of the obstacle by the detection unit continues for a first predetermined time.

  According to this projector, since the warning message is displayed when the detection of the obstacle by the detection unit continues for the first predetermined time or more, it is possible to prevent the warning message from being displayed due to the obstacle that has temporarily entered. It becomes possible.

  Application Example 3 In the projector according to the application example described above, it is preferable that the projector further includes a luminance adjustment unit that reduces the luminance of the image light when the detection unit detects the obstacle.

  According to this projector, when the detection unit detects an obstacle, the brightness of the image light is reduced, so that an increase in the temperature of the obstacle can be suppressed.

  Application Example 4 In the projector according to the application example described above, when the detection of the obstacle by the detection unit continues for a second predetermined time after the warning message is displayed in the image by the message display unit, It is desirable to further include a projection stop unit that stops the projection of the image light.

  According to this projector, since the projection of the image light is stopped when the obstacle detection continues for the second predetermined time after the warning message is displayed, it is possible to prevent the obstacle from being continuously irradiated with the image light. It becomes possible.

  Application Example 5 In the projector according to the application example, it is preferable that the projector further includes an image processing unit that blackens an image on which the warning message is displayed when the detection unit detects the obstacle.

  According to this projector, since the image on which the warning message is displayed is black, it is possible to suppress the irradiation of light to the obstacle when the warning message is displayed, that is, the temperature rise of the obstacle. .

  Application Example 6 In the projector according to the application example described above, when the detection unit detects the obstacle, at least one of switching of a display state of a state display unit indicating an operation state of the projector and generation of a warning sound. It is desirable to start.

  According to this projector, when the detection unit detects an obstacle, at least one of switching of the state display unit indicating the operation state of the projector and generation of a warning sound is started. It is possible to notify the user more reliably that the user is in the state.

  Application Example 7 In the projector according to the application example, the projector further includes a housing having an opening that guides the image light reflected by the reflection unit to the outside, and the detection unit closes at least a part of the opening. It is desirable to detect obstacles.

  According to this projector, an opening that guides image light to the outside is formed in the housing, and the projector is installed so that the opening faces upward in order for the detection unit to detect an obstacle that closes the opening. When the obstacle is placed on the housing so as to cover a part of the opening, the obstacle can be easily detected.

  Application Example 8 The projector control method according to this application example is a projector control method for projecting image light with a wide angle projected by a reflection unit and displaying an image, and the image light reflected by the reflection unit is reflected on the image light. An obstacle to be detected is detected, and when the obstacle is detected, a warning message is displayed in the image, and a display position of the warning message in the image is changed with time. To do.

  According to this projector control method, the display position of a warning message that is displayed when an obstacle is detected is changed according to the passage of time, so that a part of the projected image is hidden by the obstacle. Even so, the possibility that the warning message can be visually recognized increases as the display position changes.

  Application Example 9 In the projector control method according to the application example described above, it is desirable to display the warning message when the obstacle detection continues for a first predetermined time.

  According to this projector control method, since the warning message is displayed when the obstacle detection continues for the first predetermined time or more, it is possible to prevent the warning message from being displayed due to the obstacle that has temporarily entered. It becomes possible.

  Application Example 10 In the projector control method according to the application example described above, it is desirable to reduce the luminance of the image light when the obstacle is detected.

  According to this projector control method, when an obstacle is detected, the brightness of the image light is reduced, so that an increase in the temperature of the obstacle can be suppressed.

  Application Example 11 In the projector control method according to the application example described above, when the obstacle detection continues for a second predetermined time after the warning message is displayed, the projection of the image light is stopped. desirable.

  According to this projector control method, when the obstacle detection continues for the second predetermined time after the warning message is displayed, the obstacle is continuously irradiated with the image light in order to stop projecting the image light. It becomes possible to prevent.

  Application Example 12 In the projector control method according to the application example described above, it is preferable that an image on which the warning message is displayed is black when the obstacle is detected.

  According to this projector control method, since the image on which the warning message is displayed is black, it is possible to suppress the irradiation of light on the obstacle, that is, the temperature rise of the obstacle when the warning message is displayed. It becomes possible.

  Application Example 13 In the projector control method according to the application example described above, when the obstacle is detected, at least one of switching of the display state of the state display unit indicating the operation state of the projector and generation of a warning sound is performed. It is desirable to start.

  According to this projector control method, when an obstacle is detected, the projector detects an obstacle in order to start at least one of switching of a status display unit indicating the operation state of the projector and generation of a warning sound. It is possible to notify the user more reliably that the user is in the state.

  Application Example 14 In the projector control method according to the application example, the projector includes a housing having an opening that guides the image light reflected by the reflection unit to the outside, and at least a part of the opening is provided. It is desirable to detect obstructions that block.

  According to this projector control method, an opening that guides image light to the outside is formed in the housing, and in order to detect an obstacle that closes this opening, the projector is installed so that the opening faces upward, When the obstacle is placed on the housing so as to cover a part of the opening, the obstacle can be easily detected.

It is a figure which shows a projector, (a) is a perspective view, (b) is explanatory drawing which shows the internal structure of a projector. 1 is a block diagram showing a schematic configuration of a projector. 6 is a flowchart for explaining the operation of the projector in a power-on state. The figure which shows a message image. Explanatory drawing for demonstrating the change of the display position of a message image.

Hereinafter, a projector for projecting image light will be described with reference to the drawings.
1A and 1B are diagrams illustrating a projector according to the present embodiment, in which FIG. 1A is a perspective view and FIG. 1B is an explanatory diagram illustrating an internal configuration of the projector.
As shown in FIGS. 1A and 1B, the projector 1 includes a housing 2 that accommodates the apparatus main body, and a user performs an input operation on the upper surface 2t of the housing 2. An input operation unit 21 and an LED display unit 28 representing the operating state of the projector 1 and the like are arranged. In addition, an inclined portion 2s that is recessed in a V shape in a side view is formed on the upper surface 2t of the housing 2, and the projection window 3 and an obstacle sensor 25 as a detection unit are formed on the inclined portion 2s. Has been placed. The projection window 3 is a portion in which an opening formed in the housing 2 is closed with a light-transmitting and heat-resistant member (for example, glass), and guides image light from the inside of the housing 2 to the outside. The obstacle sensor 25 can detect an obstacle that enters the vicinity of the projection window 3 and blocks the image light.

  As shown in FIG. 1B, the projector 1 is a proximity projection type projector that projects image light onto a projection surface S (for example, a screen) at a relatively short distance, and is below the vicinity of the projection surface S. Installed. The projector 1 receives supply of image information from an external image supply device (not shown), projects image light based on this image information, and displays a projection image on the projection surface S. Inside the housing 2 are housed a lens 14 for projecting image light and a concave mirror 15 as a reflection section for widening the angle of image light to be projected. The concave mirror 15 has a concave and aspherical reflecting surface 15a, and is arranged so that the reflecting surface 15a faces the projection surface S. Then, inside the housing 2, image light is emitted toward the reflecting surface 15 a of the concave mirror 15, and the image light reflected by the concave mirror 15 is emitted outside the housing 2 through the projection window 3. . At this time, the image light converges in the vicinity of the projection window 3 and then diverges and reaches the projection plane S.

FIG. 2 is a block diagram illustrating a schematic configuration of the projector 1.
As shown in FIG. 2, the projector 1 includes an image projection unit 10, a control unit 20, an input operation unit 21, an image information input unit 22, an image processing unit 23, an OSD processing unit 24, an obstacle sensor 25, and a light source control unit 26. A power circuit 27, an LED display unit 28, a buzzer 29, and the like.

  The image projection unit 10 includes a light source device 11 as a light source, three liquid crystal light valves 12R, 12G, and 12B as light modulation devices, a projection optical system 13, a liquid crystal drive unit 16, and the like. The image projection unit 10 modulates light emitted from the light source device 11 into image light by the liquid crystal light valves 12R, 12G, and 12B, and projects the image light by the projection optical system 13 to display an image on the projection surface S. To do.

  The light source device 11 includes a discharge-type light source lamp 11a composed of an ultrahigh pressure mercury lamp, a metal halide lamp, or the like. The light emitted from the light source device 11 is converted into light having a substantially uniform luminance distribution by an integrator optical system (not shown), and red (R), green (G), which are the three primary colors of light by a color separation optical system (not shown), After being separated into blue (B) color light components, they are incident on the liquid crystal light valves 12R, 12G, and 12B, respectively.

  The liquid crystal light valves 12R, 12G, and 12B are configured by a transmissive liquid crystal panel in which liquid crystal is sealed between a pair of transparent substrates. The liquid crystal light valves 12R, 12G, and 12B include a rectangular pixel region 12a in which a plurality of pixels (not shown) are arranged in a matrix, and a driving voltage can be applied to the liquid crystal for each pixel. ing. When the liquid crystal driving unit 16 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 device 11 is modulated by transmitting through the pixel regions 12a of the liquid crystal light valves 12R, 12G, and 12B, and image light corresponding to image information is formed for each color light. The formed color image light is synthesized for each pixel by a color synthesis optical system (not shown) to become color image light.

  The projection optical system 13 includes a lens 14 and a concave mirror 15, and the image light modulated by the liquid crystal light valves 12 R, 12 G, and 12 B is widened by the concave mirror 15 and projected onto the projection plane S.

  The control unit 20 includes a CPU (Central Processing Unit) 20a, a non-volatile ROM (Read Only Memory) 20b in which control programs and setting data are stored, and a RAM (Random Access Memory) used for temporary storage of various processes. The CPU 20a executes the control program stored in the ROM 20b, and controls the operation of the projector 1 by performing arithmetic processing while temporarily storing necessary information in the RAM 20c. That is, the control unit 20 functions as a computer.

  The input operation unit 21 receives user input operations, and includes a plurality of operation keys for the user to give various instructions to the projector 1. When the user operates various operation keys of the input operation unit 21, the input operation unit 21 receives this operation and outputs a control signal corresponding to the operated operation key to the control unit 20. When the control signal is input from the input operation unit 21, the control unit 20 controls the operation of the projector 1 by performing processing based on the input control signal. The input operation 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 operation content of the user, and a receiving unit (not shown) receives the signal and transmits it to the control unit 20.

  The image information input unit 22 includes a plurality of input terminals, and various types of image information are input to these input terminals from an external image supply device (not shown) such as a video playback device or a personal computer. The image information input unit 22 outputs the input image information to the image processing unit 23.

  The image processing unit 23 defines the image information input from the image information input unit 22 as image information representing the gradation of each pixel of the liquid crystal light valves 12R, 12G, and 12B, that is, a drive voltage applied to each pixel. Convert to image information. Here, the converted image information includes a plurality of pixel values corresponding to the respective pixels of the liquid crystal light valves 12R, 12G, and 12B. The pixel value determines the light transmittance of the corresponding pixel, and the luminance of light emitted from each pixel is defined by the pixel value. Further, the image processing unit 23 performs an image quality adjustment process for adjusting the image quality such as brightness, contrast, sharpness, hue, and the like on the converted image information based on an instruction from the control unit 20. Is output to the OSD processing unit 24.

  Further, the image processing unit 23 can perform a process of setting all the pixel values to the minimum value (0) so that the light transmittance of all the pixels is minimized based on an instruction from the control unit 20. . In this case, the OSD processing unit 24 outputs image information in which all pixel values are set to 0, that is, image information representing a black plain image (black image), and a black image is projected from the image projection unit 10. The As described above, the image processing unit 23 determines the state of projecting an image (input image) based on the image information input to the image information input unit 22 and the state of projecting a black image according to an instruction from the control unit 20. Can be switched.

  The OSD processing unit 24 superimposes and displays an OSD (on-screen display) image such as a menu image or a message image on an image based on image information input from the image processing unit 23 based on an instruction from the control unit 20. Process to do. The OSD processing unit 24 includes an OSD memory (not shown), and stores OSD image information representing graphics, fonts, and the like for forming an OSD image. When the control unit 20 instructs to superimpose an OSD image, the OSD processing unit 24 reads out necessary OSD image information from the OSD memory and superimposes the OSD image at a predetermined position on the image. The OSD image information is synthesized with the image information input from the. The image information combined with the OSD image information is output to the liquid crystal driving unit 16. If there is no instruction to superimpose the OSD image from the control unit 20, the OSD processing unit 24 outputs the image information input from the image processing unit 23 to the liquid crystal driving unit 16 as it is.

  Thereafter, when the liquid crystal driving unit 16 drives the liquid crystal light valves 12R, 12G, and 12B according to the image information input from the OSD processing unit 24, the light emitted from the light source device 11 is transmitted by the liquid crystal light valves 12R, 12G, and 12B. The light is modulated into image light corresponding to the image information and projected from the projection optical system 13.

  The obstacle sensor 25 includes, for example, a light emitting device that emits infrared light (for example, a light emitting diode) and a light receiving device that receives infrared light (for example, a phototransistor), and the obstacle sensor 25 has entered the vicinity of the projection window 3. An object is detected, and the detection result is output to the control unit 20. Specifically, the obstacle sensor 25 detects an obstacle that blocks at least a part of the projection window 3 (opening) and blocks the image light.

  The light source control unit 26 controls lighting of the light source device 11 (light source lamp 11a) based on an instruction from the control unit 20. Specifically, the light source control unit 26 can turn on the light source lamp 11a by supplying predetermined power to the light source lamp 11a, and can turn off the light source lamp 11a by stopping the supply of power. The light source control unit 26 also functions as a luminance adjustment unit, and adjusts the luminance (brightness) of the light source lamp 11a by controlling the power supplied to the light source lamp 11a based on an instruction from the control unit 20. Can do. In the present embodiment, it is possible to adjust in two stages of relatively bright “high luminance” and relatively dark “low luminance”.

  The power supply circuit 27 is supplied with commercial power such as AC 100V from the outside. The power supply circuit 27 converts a commercial power supply (AC power supply) into a DC power supply having a predetermined voltage and supplies power to each part of the projector 1 (the supply path to each part is not shown). In addition, the power supply circuit 27 stops supplying power (operating power) necessary for image projection 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 standby state and a standby state for an operation for turning on the power.

  The LED display unit 28 is an indicator provided with an LED (light emitting diode), and switches the display state (lighted, blinking, extinguished, light emitting color, etc.) based on an instruction from the control unit 20, thereby allowing the user of the projector 1. Notifies the operating status (power on / off, occurrence of abnormality, etc.). The LED display unit 28 corresponds to a status display unit.

  The buzzer 29 is composed of, for example, a piezoelectric buzzer, and generates a warning sound (beep sound) based on an instruction from the control unit 20. The buzzer 29 corresponds to a warning sound generator.

Next, the operation of the projector 1 will be described.
When commercial power is supplied to the projector 1, the power supply circuit 27 supplies standby power (standby power) to at least the control unit 20, the input operation unit 21, and the LED display unit 28, and the control unit 20 supplies the power. In response, the operation according to the control program is started. Immediately after the commercial power is supplied, the projector 1 is in a standby state (also referred to as “power-off state”), in which the LED display unit 28 is turned on in orange and the light source lamp 11a is turned off. Is maintained. When the user operates the power key of the input operation unit 21 (ON operation), the control unit 20 instructs the power supply circuit 27 to start supplying operating power to each unit, and powers the projector 1. Transition to the on state.

  When the projector 1 shifts to the power-on state, the control unit 20 turns on the LED display unit 28 in green and instructs the light source control unit 26 to turn on the light source lamp 11a. As a result, an image based on the image information input to the image information input unit 22 is projected from the image projection unit 10. Further, the obstacle sensor 25 starts an operation for detecting an obstacle and outputs a detection result to the control unit 20.

  FIG. 3 is a flowchart for explaining the operation of the projector 1 in the power-on state. When the user turns on the light source lamp 11a, the control unit 20 operates according to the flow shown in FIG.

  As shown in FIG. 3, in step S <b> 101, the control unit 20 determines whether the obstacle sensor 25 has detected an obstacle in the vicinity of the projection window 3 based on the detection result of the obstacle sensor 25. If an obstacle is detected, the process proceeds to step S102. If no obstacle is detected, this step is repeated.

  When the obstacle sensor 25 detects an obstacle and proceeds to step S102, the control unit 20 sets the luminance of the light source lamp 11a to low luminance. Along with this, the luminance of the image light projected from the image projection unit 10 decreases. Note that, if the brightness has already been set, the state is maintained.

  In step S <b> 103, the control unit 20 determines whether or not the obstacle sensor 25 continues to detect an obstacle based on the detection result of the obstacle sensor 25. If an obstacle is still detected, the process proceeds to step S104. If the obstacle is removed and no longer detected, the process proceeds to step S112.

  When the obstacle is not detected and the process proceeds to step S112, the control unit 20 returns the luminance of the light source lamp 11a to the luminance before the obstacle is detected, and returns to step S101. That is, if the high brightness is set before the obstacle is detected, the high brightness is restored, and if the obstacle is set, the state is maintained.

  On the other hand, when the obstacle detection continues in step S103 and the process proceeds to step S104, the control unit 20 determines whether the obstacle detection state continues for a predetermined time t1 or more, that is, step It is determined whether or not a predetermined time t1 has elapsed since the obstacle was detected in S101. When the predetermined time t1 has elapsed, the process proceeds to step S105, and when the predetermined time t1 has not elapsed, the process returns to step S103. The predetermined time t1 is set to several seconds, for example. When the obstacle detection continues for the predetermined time t1, a warning (notification) is given to the user. On the other hand, if the obstacle is removed before the predetermined time t1 elapses, no warning is given to the user. The predetermined time t1 corresponds to the first predetermined time.

  When the obstacle detection continues for a predetermined time t1 or longer and the process proceeds to step S105, the control unit 20 causes the LED display unit 28 to blink in red and starts the buzzer 29, that is, the generation of a warning sound, The user is notified that the projector 1 is in an abnormal state.

  In step S106, the control unit 20 instructs the image processing unit 23 to project a black image. In step S107, the control unit 20 instructs the OSD processing unit 24 to display the message image Pm (see FIG. 4) superimposed on the black image. That is, the control unit 20 displays the message image Pm on a black background.

FIG. 4 is a diagram showing the message image Pm, and FIG. 5 is an explanatory diagram for explaining the change of the display position of the message image Pm.
As shown in FIG. 4, in the message image Pm, a warning message Ms prompting the user to remove the obstacle (for example, “please remove the obstacle near the projection window”) is written inside a substantially rectangular area. It is an image that was made. The width of the message image Pm is ½ or less of the width of the image projected from the image projection unit 10 (projection image Pa), and the height of the message image Pm is １ ／ or less of the height of the projection image Pa. It is. That is, the area of the message image Pm is 1/6 or less of the area of the projection image Pa. First, the control unit 20 displays the message image Pm at the position shown in FIG. 4, that is, the upper left position L1 (see FIG. 5) in the projection image Pa, and then changes the position of the message image Pm as time passes. Change (details will be described later).

  In step S108, the control unit 20 determines whether or not the obstacle sensor 25 continues to detect the obstacle based on the detection result of the obstacle sensor 25. If an obstacle is still detected, the process proceeds to step S113. If the obstacle is removed and no longer detected, the process proceeds to step S109.

  When the obstacle is not detected and the process proceeds to step S109, the control unit 20 stops the notification by the LED display unit 28 and the buzzer 29. That is, the control unit 20 returns the LED display unit 28 to a green lighting state and stops the buzzer 29 from ringing.

  In step S110, the control unit 20 instructs the OSD processing unit 24 to end the superimposed display of the message image Pm. In step S111, the control unit 20 instructs the image processing unit 23 to end the projection of the black image, and returns to the state of projecting the input image. In step S112, as described above, the control unit 20 returns the luminance of the light source lamp 11a to the luminance before the obstacle is detected, and returns to step S101. As a result, the operating state of the projector 1 returns to the state before the obstacle is detected.

  On the other hand, when the obstacle detection is continued in step S108 and the process proceeds to step S113, the control unit 20 displays a message image Pm at the current position, and a predetermined time t2 (for example, several seconds) has elapsed. Determine whether or not. That is, the first time measurement for the predetermined time t2 is started in step S107. When the predetermined time t2 has elapsed, the process proceeds to step S114, and when the predetermined time t2 has not elapsed, the process proceeds to step S116. In the present embodiment, the control unit 20 measures time for various predetermined times, but is not particularly limited to the control unit 20 and may be performed by various time measuring means.

  When the predetermined time t2 has elapsed and the process proceeds to step S114, the control unit 20 instructs the OSD processing unit 24 to change the display position of the message image Pm in the projection image Pa. In step S115, the time count for the predetermined time t2 is initialized (set to 0). Furthermore, with the initialization of the time measurement, the control unit 20 starts time measurement for the predetermined time t2 from zero.

  For example, the control unit 20 displays the message image Pm at the position L1 (upper left) shown in FIG. 5 in step S107, and further determines that the predetermined time t2 has elapsed since the message image Pm was displayed at the position L1. In this case, as shown in FIG. 5, the control unit 20 changes the display position of the message image Pm to a position L2 (upper right). Then, the control unit 20 initializes the time measurement for the predetermined time t2 and restarts the time measurement from 0. Thereafter, the control unit 20 changes the display position of the message image Pm in the order of the position L3 (center), the position L4 (lower left), and the position L5 (lower right) every time the predetermined time t2 elapses. Returning to the position L1, the change of the display position is repeated in the same order.

  In step S116, the control unit 20 determines whether or not a predetermined time t3 (for example, several minutes) has elapsed since the message image Pm was displayed in step S107. That is, the control unit 20 determines whether or not the obstacle detection has continued for a predetermined time t3 or more after displaying the message image Pm. If the predetermined time t3 has elapsed, the process proceeds to step S117. If the predetermined time t3 has not elapsed, the process returns to step S108. The predetermined time t3 corresponds to a second predetermined time.

  When the predetermined time t3 has elapsed after displaying the message image Pm and the process proceeds to step S117, the control unit 20 performs an abnormal stop process and ends the flow. Specifically, the control unit 20 instructs the light source control unit 26 to turn off the light source lamp 11a and stop the projection of the image light. Thereafter, the control unit 20 instructs the power supply circuit 27 to stop the supply of the operating power, thereby shifting the projector 1 to the standby state. However, the control unit 20 keeps the LED display unit 28 blinking in red and continues to notify that the projector 1 is in an abnormal state.

  As described above, according to the projector 1 of the present embodiment, the following effects can be obtained.

  (1) According to the projector 1 of the present embodiment, the control unit 20 changes the display position of the message image Pm displayed when the obstacle sensor 25 detects an obstacle according to the passage of time. Even when a part of the projection image Pa is hidden by an obstacle, the possibility that the message image Pm can be visually recognized by changing the display position is increased.

  (2) According to the projector 1 of the present embodiment, when the obstacle detection by the obstacle sensor 25 continues for a predetermined time t1 (first predetermined time) or longer, the message image Pm is displayed, so that the projector 1 has entered temporarily. It is possible to prevent the message image Pm from being displayed by an obstacle (for example, a user's hand).

  (3) According to the projector 1 of the present embodiment, when the obstacle sensor 25 detects an obstacle, the light source lamp 11a is set to a low brightness and the brightness of the image light is lowered. Can be suppressed.

  (4) According to the projector 1 of the present embodiment, when the obstacle detection continues for the predetermined time t3 (second predetermined time) or more after the message image Pm is displayed, the light source lamp 11a is turned off and the image light is displayed. Since the projection is stopped, it is possible to prevent the obstacle from being continuously irradiated with the image light.

  (5) According to the projector 1 of the present embodiment, even when the obstacle sensor 25 detects an obstacle, the obstacle detection is completed before the predetermined time t1 (first predetermined time) elapses. In this case, the message image Pm display, the black image projection, the LED display unit 28 blinking, the buzzer 29 ringing, and the abnormal stop process are not executed. Therefore, before an abnormality occurs (an obstacle is detected). It becomes possible to return earlier according to the operating state of the previous projector 1.

  (6) According to the projector 1 of the present embodiment, even when the obstacle sensor 25 detects an obstacle, the obstacle detection is completed before the predetermined time t3 (second predetermined time) elapses. In such a case, since the abnormal stop process is not executed, it is possible to quickly return to the operating state of the projector 1 before the abnormality occurs (before the obstacle is detected).

  (7) According to the projector 1 of the present embodiment, the image on which the message image Pm is displayed, that is, the background of the message image Pm is black, so that the light to the obstacle when the message image Pm is displayed is displayed. Irradiation, that is, temperature rise of the obstacle can be suppressed.

  (8) According to the projector 1 of the present embodiment, when the obstacle sensor 25 detects an obstacle, the control unit 20 starts blinking of the LED display unit 28 and ringing of the buzzer 29. It becomes possible to notify the user more reliably of the abnormal state.

  (9) According to the projector 1 of the present embodiment, the projection window 3 (opening) that guides image light to the outside is formed in the housing 2, and the obstacle sensor 25 detects an obstacle near the projection window 3. In order to detect, when the projector is installed so that the projection window 3 faces upward and the obstacle is placed on the casing 2 so as to cover a part of the projection window 3, the obstacle is easily removed. It becomes possible to detect.

  In the present embodiment, the control unit 20 and the OSD processing unit 24 that superimpose and display the message image Pm in step S107 correspond to the message display unit. In step S114, the display position of the message image Pm is changed. The control unit 20 and the OSD processing unit 24 correspond to the display position changing unit, and the control unit 20 for stopping the projection of the image light by performing the abnormal stop process in step S117 corresponds to the projection stop unit. Step S101 corresponds to a detection step, step S102 corresponds to a luminance adjustment step, step S106 corresponds to an image processing step, step S107 corresponds to a message display step, and step S114 corresponds to a display position change step. Step S117 corresponds to a projection stop step. Further, the “warning message” in the claims of the present application can correspond to both the warning message Ms and the message image Pm including the warning message Ms.

(Modification)
Moreover, you may change the said embodiment as follows.

  In the above embodiment, the image processing unit 23 may be provided with a function (size adjustment function) for reducing the input image. In the size adjustment function, a rectangular image forming area smaller than the pixel area 12a is set in the pixel area 12a of the liquid crystal light valves 12R, 12G, and 12B, and an input image is reduced and formed in the image forming area. The outside of the image forming area is set to black. When the input image is reduced by this size adjustment function, it is desirable to cancel the reduction of the input image when displaying the message image Pm. In this way, it is possible to prevent the visibility from being reduced due to the reduction of the warning message Ms. However, when the liquid crystal light valves 12R, 12G, and 12B have sufficiently high resolution, the message image Pm may be displayed in the image forming area.

  In the above-described embodiment, the image processing unit 23 may be provided with a function (keystone correction function) for correcting trapezoidal distortion that occurs when the casing 2 is installed with the projection surface S tilted. The keystone correction function sets an image forming area having a shape that can cancel the trapezoidal distortion in the pixel area 12a, forms an input image in the image forming area, and sets the outside of the image forming area to black. When the keystone correction function corrects the trapezoidal distortion, it is desirable to maintain the corrected state even when the message image Pm is displayed. In this case, it is possible to suppress the visibility of the message image Pm from being distorted. However, when the inclination of the housing 2 is not so large, the message image Pm may be displayed with the keystone correction function canceled.

  In the above embodiment, the size (area) of the message image Pm is 1/6 or less of the projected image Pa, and the display positions of the message image Pm are five positions L1 to L5. The number of positions is not limited to this. For example, when the liquid crystal light valves 12R, 12G, and 12B have high resolution, the message image Pm can be reduced without significantly reducing the visibility. As the message image Pm is reduced and the number of display positions is increased, the possibility that the message image Pm can be visually recognized increases even when a part of the projection image Pa is hidden by an obstacle. .

  In the above embodiment, the size of the message image Pm does not always have to be constant, and the size may be changed in the middle or gradually changed.

  In the above embodiment, the display position is sequentially changed every time the predetermined time t2 has elapsed since the message image Pm was displayed. However, the message image Pm may be moved smoothly with the passage of time.

  In the above embodiment, the display position of the message image Pm is changed every predetermined time t2, but the timing of changing the display position may be irregular.

  In the above embodiment, the display position of the message image Pm is changed according to a predetermined order, but may be changed at random.

  In the above embodiment, the background of the message image Pm is black with a minimum pixel value, but may be a pixel value other than the minimum value. In addition, a color other than black or an input image may be used as the background, but it is desirable that the background be a dark color in order to suppress light irradiation to the obstacle.

  In the above embodiment, in step S105, the control unit 20 causes the LED display unit 28 to blink and the buzzer 29 to sound to notify the user that the projector 1 is in an abnormal state. Only one of them may be executed. Accordingly, in step S109, the control unit 20 stops one of the executed executions.

  In the above embodiment, when the predetermined time t1 has elapsed since the obstacle was detected in step S104, the processes of steps S105 to S107 are performed. However, these processes may be performed in any order. In step S108, when no obstacle is detected, the processes in steps S109 to S111 are performed. However, these processes may be performed in any order.

  In the above embodiment, the three-plate projector 1 using the three liquid crystal light valves 12R, 12G, and 12B as the light modulation device has been described. However, the present invention is not limited to this. For example, a mode in which each pixel is modulated into image light by a single liquid crystal light valve including sub-pixels that can transmit R light, G light, and B light can be employed.

  In the above-described embodiment, the transmissive liquid crystal light valves 12R, 12G, and 12B are used as the light modulator, but a reflective light modulator such as a reflective liquid crystal light valve can also be used. 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.

  In the above embodiment, the light source device 11 is constituted by the discharge-type light source lamp 11a, but it can also be applied to a solid light source such as an LED light source or a laser light source, or other light sources.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 2 ... Housing | casing, 2s ... Inclination part, 2t ... Upper surface, 3 ... Projection window, 10 ... Image projection part, 11 ... Light source device, 11a ... Light source lamp, 12R, 12G, 12B ... Liquid crystal light valve, 12a ... Pixel area, 13 ... Projection optical system, 14 ... Lens, 15 ... Concave mirror, 15a ... Reflective surface, 16 ... Liquid crystal drive unit, 20 ... Control unit, 20a ... CPU, 20b ... ROM, 20c ... RAM, 21 ... Input Operation unit, 22 ... Image information input unit, 23 ... Image processing unit, 24 ... OSD processing unit, 25 ... Obstacle sensor, 26 ... Light source control unit, 27 ... Power supply circuit, 28 ... LED display unit, 29 ... Buzzer, L1 , L2, L3, L4, L5 ... position, Ms ... warning message, Pa ... projected image, Pm ... message image, S ... projection surface, t1 ... predetermined time (first predetermined time), t2 ... predetermined time, t3 ... predetermined time The second predetermined time).

Claims (15)

A projector that displays image by widening and projecting image light at a reflection part,
A detection unit for detecting an obstacle that blocks the image light reflected by the reflection unit;
A message display unit for displaying a warning message in the image when the detection unit detects the obstacle;
A display position changing unit that changes the display position of the warning message in the image according to the passage of time;
A projector characterized by comprising: The projector according to claim 1,
The message display unit displays the warning message when the detection of the obstacle by the detection unit continues for a first predetermined time. The projector according to claim 1 or 2,
A projector further comprising a luminance adjusting unit that reduces the luminance of the image light when the detecting unit detects the obstacle. It is a projector as described in any one of Claims 1-3, Comprising:
A projection stop unit that stops projection of the image light when the detection of the obstacle by the detection unit continues for a second predetermined time after the warning message is displayed in the image by the message display unit; A projector comprising: It is a projector as described in any one of Claims 1-4, Comprising:
A projector further comprising: an image processing unit that blackens an image on which the warning message is displayed when the detection unit detects the obstacle. A projector according to any one of claims 1 to 5,
When the detection unit detects the obstacle, the projector starts at least one of switching of a display state of a state display unit indicating an operation state of the projector and generation of a warning sound. The projector according to any one of claims 1 to 6,
A housing having an opening for guiding the image light reflected by the reflecting portion to the outside;
The said detection part detects the obstruction which blocks at least one part of the said opening part, The projector characterized by the above-mentioned. A method for controlling a projector that displays image by widening and projecting image light at a reflection part,
Detecting an obstacle that blocks the image light reflected by the reflecting portion,
When the obstacle is detected, a warning message is displayed in the image,
A projector control method, wherein the display position of the warning message in the image is changed with the passage of time. The projector control method according to claim 8, comprising:
The projector control method, wherein the warning message is displayed when detection of the obstacle continues for a first predetermined time. A projector control method according to claim 8 or 9, wherein:
A projector control method, comprising: reducing brightness of the image light when the obstacle is detected. A method for controlling a projector according to any one of claims 8 to 10,
A projector control method comprising: stopping projection of the image light when detection of the obstacle continues for a second predetermined time after the warning message is displayed. A method for controlling a projector according to any one of claims 8 to 11,
A method for controlling a projector, characterized in that an image on which the warning message is displayed is black when the obstacle is detected. A projector control method according to any one of claims 8 to 12, comprising:
When the obstacle is detected, at least one of switching a display state of a state display unit indicating an operation state of the projector and generating a warning sound is started. A method for controlling a projector according to any one of claims 8 to 13,
The projector includes a housing having an opening that guides the image light reflected by the reflecting portion to the outside, and detects an obstacle that blocks at least a part of the opening. A method for controlling a projector according to any one of claims 8 to 14,
A projector control method, comprising: changing a size of the warning message while displaying the warning message.

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