JP5195323B2 - Projection-type image display device - Google Patents

Description

  The present invention relates to a projection video display apparatus including a plurality of light sources, and more particularly to a projection video display apparatus having a light source switching function for switching a light source to be turned on.

  In general, a projection display apparatus that projects an image on a screen uses a lamp as a light source. However, if the lamp is lit for a long time, the lamp reaches the end of its life and the lamp is burned out. Therefore, for example, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 2-257192) and Patent Document 2 (Japanese Patent Laid-Open No. 6-82909), a plurality of lamps as light sources are provided, and a lamp that has been lit is out of lamp. When this occurs, a configuration has been proposed in which a mirror that reflects light from the lamp is driven, and a lamp that is switched from a lamp that has burned out to a spare lamp is switched. However, in Patent Documents 1 and 2, since the standby lamp starts to be turned on after the lamp to be turned on is switched on, no image display time is displayed on the screen until the brightness of the standby lamp increases. turn into. To solve such a problem, for example, as shown in Patent Document 3 (Japanese Patent Laid-Open No. 2003-215704), when switching to a spare lamp, the spare lamp is turned on in advance before switching, so that there is no display. A configuration for reducing time has been proposed.

JP-A-2-257192 JP-A-6-82909 JP 2003-215704 A

  However, in the lamp switching of the device according to Patent Document 3, when the spare lamp is lit in advance, the lamp that was originally lit is lit as it is. Therefore, in the switching operation, power must be supplied not only to the lamp that is lit but also to the standby lamp, so that there is a problem that power consumption increases and a power source with a large capacity must be used.

  Therefore, according to the present invention, the brightness of the first lamp that was originally lit is reduced, and the power supplied to the first lamp is reduced when switching to the second lamp that is a spare lamp, thereby reducing the power consumption. An object of the present invention is to provide a projection-type image display device capable of a small lamp switching operation.

A projection display apparatus according to the present invention includes a first lamp and a second lamp, optical processing means for modulating light emitted from the first lamp or the second lamp and projecting it on a screen, and a current flowing through the second lamp. Current detection means for detecting a value, and lighting control means for turning on the second lamp being turned off while the first lamp is turned on, and switching the lamp that enters the optical processing means from the first lamp to the second lamp. The lighting control means turns on the first lamp at a predetermined power lower than the power at the time of steady lighting before the lamp that enters the optical processing means is switched from the first lamp to the second lamp; and when the current value flowing through the second lamp exceeds a predetermined threshold value, it is shall switch the lamp light is incident on the optical processing means from the first ramp to the second ramp.
Also, the first lamp and the second lamp, the optical processing means for modulating the light emitted from the first lamp or the second lamp and projecting it on the screen, and the current for detecting the current value flowing through the first lamp and the second lamp A lighting control unit that includes a detection unit and a lighting control unit that switches on the second lamp that is turned off while the first lamp is on and switches the lamp that enters the optical processing unit from the first lamp to the second lamp; The first lamp is lit at a predetermined power lower than the power at the time of steady lighting before the lamp that enters the optical processing means is switched from the first lamp to the second lamp, and the current of the first lamp When the difference between the value and the current value of the second lamp becomes smaller than a predetermined value, the lamp that enters the optical processing means is switched from the first lamp to the second lamp.

In the present invention, before the lamp that enters the optical processing means is switched from the first lamp to the second lamp, the first lamp is lit at a predetermined power lower than the power during steady lighting , and the second lamp when the current value flowing in the lamp exceeds a predetermined threshold value, the second lamp switching order from the first lamp, a possible lamp switching operation with a small power consumption, and luminance of the lamp is switched in more than a certain value It is possible to provide a projection-type image display apparatus that can
In addition, before the lamp that enters the optical processing means is switched from the first lamp to the second lamp, the first lamp is lit with a predetermined power lower than the power during steady lighting, and the current of the first lamp When the difference between the value and the current value of the second lamp becomes smaller than a predetermined value, the lamp is switched from the first lamp to the second lamp, so that the lamp switching operation can be performed with low power consumption and the lamp switching. The magnitude of the output from the projection-type image display device before and after can be made constant.

Embodiment 1 FIG.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.

  FIG. 1 is a diagram showing a projection type video display apparatus according to Embodiment 1 of the present invention. The projection display apparatus 2 according to Embodiment 1 includes a signal conversion circuit 20, an optical engine 11 (optical processing means), a luminance sensor 12, a control circuit 4, a lamp power supply 5, a lamp power supply 6, and a lamp 7 (first lamp). ), A lamp 8 (second lamp), a rotary motor 9 (driving means), a mirror 10 (reflecting means), and a power supply circuit 3, and is applied to the screen 1 by the light output from the projection display apparatus 2. Video is projected.

  In FIG. 1, the projection type video display device 2 is connected to an external video signal output means (for example, a personal computer) (not shown) for outputting a video signal, and is output from the video signal output means. The video signal is input to the signal conversion circuit 20. In the signal conversion circuit 20, after the input video signal is AD-converted or the like, it is converted to be enlarged or reduced to a screen resolution suitable for display so that it can be displayed on the screen 1 by projection type video display. Process. With this signal processing, a drive signal for driving a DMD (Digital Mirror Device) (registered trademark) in the optical engine 11 is generated in the signal conversion circuit 20, and the drive signal is output to the optical engine 11. Here, the optical engine 11 is an optical system including a DMD (modulation means) (not shown), and spatially modulates the input light and outputs it. The control circuit 4, the lamp power source 5 and the lamp power source 6 correspond to lighting control means, and the mirror 10 and the rotation motor 9 correspond to switching means.

  The output signal of the signal conversion circuit 20 is also input to the control circuit 4, and the control circuit 4 generates a drive signal for driving the lamp power source 5 and the lamp power source 6 based on the input output signal, and the lamp power source 5 and lamp power supply 6 respectively. The lamp power supply 5 drives the lamp 7 based on the drive signal input from the control circuit 4, and the lamp power supply 6 drives the lamp 8 based on the drive signal input from the control circuit 4. The output of one of the lamps is input to the optical engine 11 via the mirror 10 (lamp 7 in FIG. 1), and the output of the lamp input to the optical engine 11 is a drive signal output from the signal conversion circuit 20. The signal is spatially modulated by the DMD driven by the signal output from the control circuit 4 and projected onto the screen 1 by a projection lens (output means) (not shown) provided in the optical engine 11. As a result, an image based on the image signal input to the signal conversion circuit 20 is displayed on the screen 1.

  The luminance sensor 12 measures the luminance level of the light output from the optical engine 11 and outputs it to the control circuit 4. The control circuit 4 controls the first lamp 7 and the second lamp 8 by changing the position of the mirror 10 by controlling the rotary motor 9 when the brightness of the currently lit lamp decreases according to the output of the brightness sensor 12. The output is controlled to be switched. The power supply circuit 3 is power supply means for supplying power to the lamp power supply 5, the lamp power supply 6, the control means 4, and the signal conversion circuit 20.

  Next, the lamp switching operation in the control circuit 4 will be described with reference to FIG. FIG. 2 is a flowchart showing a lamp switching operation for switching the lamp from the lamp 7 to the lamp 8.

  The output of the optical engine 11 is constantly measured by the luminance sensor 12, and the measurement result is input to the control circuit 4. When the luminance level of the light output from the optical engine 11 is below a certain value (S1), the control circuit 4 outputs a drive signal to the lamp power source 6 to light the lamp 8, and the lamp power source 6 The lighting of the lamp 8 is started based on the drive signal (S2). At the same time or after a certain period of time has elapsed, the control circuit 4 outputs a drive signal to the lamp power supply 5 so as to reduce the value of the current flowing through the lamp 7, and the lamp power supply 5 flows to the lamp 7 based on the drive signal. The lamp 7 is controlled so as to reduce the current value (S3).

  Next, after waiting for T1 time (after performing WAIT) (S4), the control circuit 4 outputs a change signal to the rotating motor 9, and the rotating motor 9 outputs the output of the lamp 8 to the optical engine 11 by the change signal. The position of the mirror 10 is changed so as to be input (lamp change) (S5). Thereafter, the control circuit 4 outputs a drive signal to the lamp power supply 5 so that the lamp 7 is turned off, and the lamp power supply 5 turns off the lamp 7 based on the drive signal (S6) and ends the lamp switching operation (S6). S7).

  The brightness of the lamps 7 and 8 at the time of lamp switching actually changes as shown in FIG. FIG. 3 is a waveform diagram showing changes in the luminance levels of the lamp 7 and the lamp 8.

As shown in FIG. 3, when the lamp 7 and the lamp 8 are driven at 150 W, the output becomes 150 W, which is an output at the time of steady lighting, T2 hours after the second lamp is turned on.
When the brightness level of the light measured by the brightness sensor 12 falls below a certain value, the lamp power supply 6 starts to turn on the lamp 8 and at the same time, the lamp power supply 5 controls the current so that the output of the lamp 7 is changed from 150 W to 132 W. Do.

  After T1 time from the start of lighting of the lamp 8, the control circuit 4 outputs a change signal to the rotary motor 9 to switch the output of the lamp 7 and the lamp 8. Here, while the change signal is output from the control circuit 4 to the rotary motor 9 (time t), the output of the lamp is not input to the optical engine 11 because the mirror 10 is rotating. Therefore, the time t in FIG. 3 is a non-display time when nothing is displayed on the screen 1. Here, in the case of a normal lamp, the T2 time is about 2 minutes, the time T1 that is the WAIT time is set to 1 minute, and the time t required for the lamp to switch by the change signal is about 1.5 seconds. It is.

  As described above, in the projection display apparatus according to Embodiment 1, the current of the lamp 7 is already controlled so that the output power becomes small before the change signal is output. Power consumption can be reduced even when the lamps are lit at the same time, and the lamp temperature after the lamp is turned off can be lowered compared to the case where current control is not performed. Even when the lamp is replaced, it can be safely done without worrying about burns.

  In addition, since the power of the lamp 7 is reduced to 132 W from when the lamp 8 starts to be turned on until the lamp 7 is turned off, the lamp 7 and the lamp 8 are turned on in the lamp switching operation. The required power can be suppressed to 132 W (Lamp 7) +150 W (Lamp 8) = 282 W at the maximum. Therefore, the circuit scale of the power supply circuit 3 that supplies power to the lamp power supplies 5 and 6 can be reduced, and the temperature rise in the housing of the video display device 2 can be suppressed.

  When switching from the lamp 7 to the lamp 8, the lighting of the lamp 8 is started in advance, and the switching is performed after a predetermined time has elapsed from the start of the lighting, so the non-display period on the screen 1 associated with the switching is minimized. it can.

  In addition, by setting the WAIT time to about 1 minute, the output of the lamp 8 after the lamp switching becomes approximately 132 W, which is a level substantially equal to the power of the lamp 7 before the lamp switching, and is thus projected on the screen 1 before and after the lamp switching. It is possible to suppress a change in the luminance level of the light to be reduced.

  Further, since the lamp 7 is turned off almost simultaneously with the output of the change signal, the power consumption of the entire video display apparatus can be further reduced. For example, if the output of the lamp 8 is 132 W when the lamp is switched as described above, it can be suppressed to about 264 W at the maximum.

  Further, when the lamp is switched after the lit lamp 7 is turned off, the non-display time during which nothing is displayed on the screen 1 becomes longer, but the luminance level of the light output from the optical engine 11 by the luminance sensor 12 is increased. Can be predicted by detecting the decrease in brightness, and the lamp 7 and the lamp 8 can be switched before the lamp break occurs.

  In the above description, the output of the lamp 7 is reduced at the same time as the lighting of the lamp 8 is started. However, the output of the lamp 7 can be reduced after a certain time has elapsed after the lighting of the lamp 8 is started. . Further, the lamp 8 can be turned on after the output of the lamp 7 is reduced.

Embodiment 2. FIG.

  In the first embodiment, the control circuit 4 outputs a change signal to the rotary motor 9 after performing a WAIT for a predetermined time when the lamp is replaced. However, the current detection means measures the value of the current flowing through the lamp 8. The lamp power supply 6 can be provided with the function as described above, and the lamp can be switched based on the current value measured by the lamp power supply 6. For example, after the lighting of the lamp 8 starts, when the current value flowing through the lamp 8 becomes equal to or higher than a threshold value, it is determined that the luminance of the lamp 8 has reached a certain level or more, and the control circuit 4 applies to the rotary motor 9. Control may be performed so as to output a change signal.

  The lamp switching operation as described above will be described with reference to FIG. FIG. 4 is a flowchart showing the lamp switching operation based on the current value of the lamp 8. In FIG. 4, the same steps as those in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted except for some steps.

  In FIG. 4, when the luminance level of the optical engine 11 becomes a predetermined value or less, the control circuit 4 outputs a lighting signal to the lamp power supply 8 (S 2), and at the same time, the lamp 7 to the lamp power supply 5. The current value is controlled to be small (S3). Next, the value of the current flowing through the lamp power supply 8 is measured in the lamp power supply 6, and when the lamp current becomes Ith or more (S8), the control circuit 4 outputs a change signal to the rotary motor 9 (S5).

  FIG. 5 is a waveform diagram showing changes in the luminance levels of the lamp 7 and the lamp 8. When the output power of the lamp 8 increases as shown in FIG. 5, the value of the current flowing through the lamp 8 at the time Ts is calculated so that the lamp 8 output becomes 132 W at the time Te when the switching of the lamp is completed. Ith. In the case of a normal lamp, T2 is about 2 minutes, and it takes about 1.5 seconds for the lamp to be switched by a change signal. Therefore, Ith has a power of 132 W (lamp switching) What is necessary is just to select the electric current used as the power consumption of the previous lamp 7.

  If the change signal is managed by WAIT for a certain period of time as in the first embodiment, if the lamp 8 fails to be lit, a non-display period will occur even after the lamp is switched. If the current value is measured, even if the lighting of the lamp 8 fails, the lamp can be switched after confirming that the lamp 8 has been lit by a re-lighting operation, etc. The period can be minimized.

  In the second embodiment, the lamp is switched when the value of the current flowing through the lamp 8 becomes Ith. However, the lamp power source 5 has a function as a current detection means for measuring the current value flowing through the lamp 7. When the current values flowing in the lamps 7 and 8 become equal, or when the difference becomes a certain value or less, control is performed so that the lamps are switched, whereby the projection-type image display device 2 before and after the lamps are switched. The output from the can be kept constant.

As the lamp 7 and the lamp 8, a halogen lamp, a high-intensity discharge lamp, or the like can be used.

  In the above description, the DMD is used to spatially modulate the light output from the mirror 10. However, another light valve such as a transmissive or reflective liquid crystal display element may be used.

It is the schematic of the projection type video display apparatus concerning this embodiment. It is a flowchart which shows the lamp | ramp switching operation | movement which concerns on this embodiment. It is the wave form diagram shown about the change of the luminance level of the lamp | ramp which concerns on this embodiment. It is a flowchart which shows the lamp | ramp switching operation | movement which concerns on other embodiment. It is the wave form diagram shown about the change of the luminance level of the lamp | ramp which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Screen 3 Power supply circuit 4 Control circuit 5,6 Lamp power supply 7,8 Lamp 9 Rotating motor 10 Mirror 11 Optical engine 12 Luminance sensor 20 Signal conversion circuit

Claims (4)

A first lamp and a second lamp, an optical processing means for modulating the light emitted from the first lamp or the second lamp and projecting it on a screen, a current detection means for detecting a current value flowing through the second lamp, A lighting control means for turning on a second lamp that is turned off while the first lamp is turned on, and switching a lamp that enters the optical processing means from the first lamp to the second lamp; , the prior lamp which light enters is switched to the second lamp from the first lamp to the optical processing means, together with the turns on the first lamp a predetermined power lower than the power of the rated operation, the when the current value flowing through the second lamp exceeds a predetermined threshold value, and wherein the switching to the second lamp a lamp is incident light to the optical processing means from said first ramp Cum-type image display device. A first lamp and a second lamp; an optical processing means for modulating light emitted from the first lamp or the second lamp and projecting the light onto a screen; and a current for detecting a current value flowing through the first lamp and the second lamp. Detecting means; and a lighting control means for turning on the second lamp being turned off while the first lamp is turned on, and switching the lamp that enters the optical processing means from the first lamp to the second lamp, The lighting control means turns on the first lamp with a predetermined power lower than the power at the time of steady lighting before the lamp that enters the optical processing means is switched from the first lamp to the second lamp. And when the difference between the current value of the first lamp and the current value of the second lamp becomes smaller than a predetermined value, a lamp that makes light incident on the optical processing means is removed from the first lamp. Projection display device characterized by switching to serial second lamp. Luminance detection means for detecting the luminance level of the light output from the optical processing means is further provided, and the lighting control means starts lighting the second lamp when the luminance level becomes a predetermined threshold value or less. The projection type image display device according to claim 1 or 2 . Reflecting means for reflecting light emitted from the first lamp or the second lamp toward the optical processing means, and a lamp for driving the reflecting means and reflecting the light from the first lamp to the second lamp. The projection type image display apparatus according to claim 1, further comprising a switching unit including a switching driving unit, wherein the lighting control unit controls the switching unit .

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