JP2007163973A - Light source device and projector equipped with light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device which excellently emits laser beams and to provide a projector unit. <P>SOLUTION: In the light source device of the projector unit, a laser array 311 is equipped with a plurality of laser light source units 311A each having at least one laser light source, and a driving switch 313 is switched in sequence under the control of a control unit to make those laser light source groups cyclically illuminate through sequential pulse driving. Consequently, laswer ligh with high output can be emitted with a small current consumption and temporal use efficiency is improved by continuous projection of the laser light. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a light source device that emits laser light and a projector including the light source device.

  Conventionally, there is a projector that uses a laser light source that emits laser light as a light source for a projector (see, for example, Patent Document 1).

  The one described in Patent Document 1 is a laser illumination optical system that converts a laser beam emitted from a laser array light source constituted by a plurality of laser light sources into a uniform intensity by a hologram element.

JP 2003-149594 A (refer to pages 3 to 7, see FIGS. 1 to 4)

  Incidentally, in order to oscillate high-power laser light from a conventional laser illumination optical system as described in Patent Document 1, it is necessary to apply a large current. In particular, when the wavelength of laser light oscillated from a laser light source is converted by SHG (Second-Harmonic Generation), the amount of light emitted from SHG is proportional to the square of the amount of light incident on SHG. In order to increase the output, it is necessary to increase the output of the laser beam from the laser light source. For this purpose, it is effective to increase the output of laser light and increase the conversion efficiency of SHG by applying a large current instantaneously by pulse driving. However, although instantaneous, applying a large current to the laser light source requires a power source with a large current capacity, resulting in low cost efficiency. In particular, when a plurality of laser light sources are connected in parallel, a large current is applied to each of these laser light sources. Therefore, it is necessary to select a power supply device that supports a large current, which is more cost effective. Becomes worse. Furthermore, there is a problem that the time utilization efficiency of the power source is deteriorated.

  In view of the above problems, an object of the present invention is to provide a light source device that emits good laser light with low power and a projector including the light source device.

  A light source device according to the present invention is provided with a laser array in which a plurality of laser light sources are arranged in a matrix and a laser light emission surface of the laser array, and the wavelength of the laser light emitted from the laser array is determined. A light source device including a wavelength conversion element for conversion and a lighting drive unit that performs lighting driving of the laser array, wherein the lighting drive unit is set by dividing a plurality of laser light sources in the laser array. Each of the groups is sequentially pulsed to light cyclically.

  According to this invention, the lighting drive unit sequentially drives each of the groups set by dividing the plurality of laser light sources in the laser array. Thereby, since pulse driving is sequentially performed for each group, it is possible to emit a high-power laser beam with a smaller amount of current than when a pulse current is supplied to all laser light sources. Further, by sequentially driving each group with pulses, the entire laser array can emit continuous laser light, and the temporal utilization efficiency is improved as compared with the conventional configuration.

  The projector according to the present invention includes a plurality of light source devices that emit laser beams having different wavelengths, a plurality of light modulation elements that modulate the laser light emitted from each light source device according to image information, and each light modulation device. A projector comprising a color combining optical system for combining converted modulated light and a projection optical system for enlarging and projecting the combined light, wherein the light source device is a laser array in which a plurality of laser light sources are arranged in a matrix. A wavelength conversion element that is provided opposite to the laser light emission surface of the laser array and converts the wavelength of the laser light emitted from the laser array, and a lighting drive unit that performs lighting driving of the laser array. And the lighting driving unit sequentially pulsates each of the groups set by dividing the plurality of laser light sources in the laser array to light cyclically. And wherein the door.

  According to the present invention, since the projector includes the light source device as described above, power for driving the light source device is reduced, so that power consumption for driving the projector is also reduced. Further, the projector can be miniaturized by reducing the size of the light source device.

  On the other hand, a projector according to the present invention includes a plurality of light source devices that emit laser beams having different wavelengths, a plurality of light modulation elements that modulate the laser light emitted from each light source device according to image information, and each light modulation device. A projector comprising a color synthesis optical system for synthesizing modulated light converted by an element and a projection optical system for enlarging and projecting the synthesized light, wherein the light source device has a plurality of laser light sources arranged in a matrix A laser array; and a wavelength conversion element provided opposite to the laser light emission surface of the laser array for converting the wavelength of the laser light emitted from the laser array, and sequentially driving the plurality of light source devices in pulses. It is also possible to consider a configuration having a drive device that turns on cyclically.

  According to the present invention, the driving device is a light source device corresponding to laser light having a plurality of wavelengths, for example, a light source device that emits red laser light, a light source device that emits blue laser light, and a light source device that emits green laser light. Are sequentially pulsed to light up cyclically. With this configuration, the laser light from the optical system including a plurality of light source devices that emit laser light of different wavelengths is reflected to DMD (Digital Micromirror Device: trademark of Texas Instruments). It can also be applied to a DLP (Digital Light Processing) projector that projects the reflected light in an enlarged manner. Thereby, also in such a DLP system projector, the electric power for driving these light source devices can be reduced.

  In the present invention, the light source device includes a lighting drive unit that sequentially pulsates and cyclically lights each of the groups set by dividing a plurality of laser light sources in the laser array, and the drive device and It is preferable to cyclically light a combination of groups in an arbitrary laser array by a combination of switching of each lighting drive unit.

  According to the present invention, the plurality of light source devices sequentially pulse-driven by the driving device are lit to cyclically light each of the groups set by dividing the plurality of laser light sources in the laser array. A drive unit is provided, and a combination of groups in an arbitrary laser array is cyclically lit by a combination of switching of the drive device and the lighting drive unit. Thereby, the electric power required in order to drive each of the light source device which comprises an optical system can be further reduced by switching switching of a drive device and a lighting drive part.

[First embodiment]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[Main configuration of rear projector]
FIG. 1 is a sectional side view of a rear projector according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a rear projector. The rear projector 1 includes a cabinet 2, a projector unit 3 as a projector, a control unit 4 constituting a part of a lighting drive unit and a drive device, and a reflection mirror 5. And a transmissive screen 6.

  As shown in FIG. 1, the cabinet 2 is configured in a box shape whose back side (right side in FIG. 1) is inclined, and houses and arranges the projector unit 3, the control unit 4, and the reflection mirror 5 therein. Although not specifically shown, the cabinet 2 includes a power supply unit that supplies power to each component of the rear projector 1, in addition to the projector unit 3, the control unit 4, and the reflection mirror 5, and a rear unit. A cooling unit that cools the inside of the projector 1, a sound output unit that outputs sound, and the like are disposed.

  An opening 21 having a rectangular shape in plan view is formed on the front side of the cabinet 2 (on the left side in FIG. 1), and the transmission screen 6 is supported and fixed on the periphery of the opening 21.

  The projector unit 3 is disposed on the bottom surface in the cabinet 2, forms image light L based on an image signal output from the control unit 4, and magnifies and projects the image light L toward the reflection mirror 5. A specific configuration of the projector unit 3 will be described later.

  Although not specifically shown, the control unit 4 includes, for example, a tuner, an IF circuit, an audio detection circuit, a video detection circuit, an amplification circuit, a CPU, and the like, and comprehensively controls the projector unit 3. . Further, the control unit 4 extracts, for example, a broadcast signal having a frequency corresponding to a channel selected by operating a remote controller (not shown), outputs an image signal to the projector unit 3, and outputs an audio signal to an audio output unit. (Not shown). Further, the control unit 4 controls the drive of the light source device 31 by controlling the operation of a drive switch 313 described later.

  The reflection mirror 5 is disposed on the upper back side in the cabinet 2 and reflects the image light L projected by the projector unit 3 to the back side of the transmissive screen 6.

  The transmission screen 6 has a rectangular shape and is supported and fixed to the periphery of the opening 21 of the cabinet 2. The transmissive screen 6 includes a Fresnel lens sheet 61 disposed on the back side and a lenticular lens sheet 62 disposed on the front side. The transmissive screen 6 converts the image light L incident through the reflection mirror 5 into parallel light by the Fresnel lens sheet 61, and converts the parallel light into enlarged (diffused) light by the lenticular lens sheet 62. Then, the projected image is displayed by projecting the image light from the back side to the front side.

[Configuration of projector unit]
Next, the configuration of the projector unit 3 will be described with reference to FIG. FIG. 2 is a schematic diagram showing an outline of an optical system configured inside the projector unit.
The projector unit 3 includes a light source device 31, a liquid crystal panel 32 that constitutes a light modulation element, a polarizing plate 33 that constitutes a light modulation element, a cross dichroic prism 34 as a color synthesis optical system, and a projection as a projection optical system. A lens 35, and the like.

  The light source device 31 is turned on based on the control signal input from the control device described above, and emits laser light toward the liquid crystal panel 32. These light source devices 31 include a red light source device 31R that emits red laser light, a blue light source device 31B that emits blue laser light, and a green light source device 31G that emits green laser light. As shown in FIG. 2, these light source devices 31 are disposed so as to face the three side surfaces of the cross dichroic prism 34, respectively. At this time, each light source device 31 is disposed so that the red light source device 31R and the blue light source device 31B face each other and the projection lens 35 and the green light source device 31G face each other across the cross dichroic prism 34. A detailed description of these light source devices 31 will be described later.

  The liquid crystal panel 32 uses, for example, a polysilicon TFT (Thin Film Transistor) as a switching element, and each color light emitted from the light source device 31 is transmitted between these three liquid crystal panels 32 and their light beam incident sides and An optical image is formed by being modulated according to image information by the polarizing plate 33 on the exit side.

  The polarizing plate 33 includes an incident-side polarizing plate 331 and an emission-side polarizing plate 332 that are disposed on the front side and the rear side of the optical path of the liquid crystal panel 32. The incident-side polarizing plate 331 transmits only polarized light in a certain direction out of each color light emitted from the light source device 31 and absorbs other light beams. A polarizing film is attached to a substrate made of quartz or sapphire. It has been done. The exit-side polarizing plate 332 is configured in substantially the same manner as the incident-side polarizing plate 331, and transmits only polarized light in a predetermined direction and absorbs other light beams out of the light beams emitted from the liquid crystal panel 32. Further, the polarizing film may be attached to the cross dichroic prism 34 without using the substrate, or the substrate may be attached to the cross dichroic prism 34. The incident side polarizing plate 331 and the exit side polarizing plate 332 are set so that the directions of the polarization axes thereof are orthogonal to each other.

  The cross dichroic prism 34 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from each liquid crystal panel 32. The cross dichroic prism 34 has a substantially square shape in plan view in which four right angle prisms are bonded together, and two dielectric multilayer films are formed at the interface where the right angle prisms are bonded together. These dielectric multilayer films reflect the color lights emitted from the liquid crystal panels 32 facing each other and transmit the color lights emitted from the liquid crystal panel 32 opposed to the projection lens 35. In this manner, the color lights modulated by the liquid crystal panels 32 are combined to form a color image.

  The projection lens 35 is configured as a combined lens in which a plurality of lenses are combined. The projection lens 35 forms image light L based on the color image formed by the cross dichroic prism 34 and enlarges and projects the image light L toward the reflection mirror 5.

(Configuration of light source device)
Next, the configuration of the light source device 31 will be described with reference to FIG. FIG. 3 is a schematic diagram showing an outline of a drive circuit of the light source device. FIG. 4 is a cross-sectional view schematically showing a schematic configuration of the light source device.

  In FIG. 3, each light source device 31 includes a laser array 311, a power supply unit 312, and a drive switch 313 as a lighting drive unit.

  The laser array 311 is formed by arranging a plurality of laser light sources 41 in a matrix. The plurality of laser light sources 41 constituting the laser array 311 are grouped by a predetermined number to constitute a laser light source unit 311A. In addition, although the laser light source unit 311A in this Embodiment shows the example provided with the one laser light source 41, respectively, it is not limited to this, It is good also as a structure provided with the several laser light source 41. FIG.

Here, the configuration of the laser array 311 will be described in more detail with reference to FIG. In FIG. 4, the laser array 311 has a configuration including one laser light source 41, but actually, a plurality of such laser light sources 41 are arranged in a matrix as described above.
The laser array 311 includes an infrared laser light source formed on the n-type semiconductor substrate 411, an SHG (Second-Harmonic Generation) element 415 that converts the infrared laser light source 41 into RGB visible light, and transmits visible light to the outside. And an external coupler 416 for reflecting infrared light to the inside. The infrared laser light source 41 includes an n-type GaAs semiconductor substrate 411, a mirror layer 412, an active layer 413 having a quantum well structure, and a p-type semiconductor layer 414.

  The active layer 413 is provided with an electrode (not shown) for injecting current, and laser light is oscillated by applying current from the electrode. Laser light generated in the active layer 413 is emitted by the mirror layer 412 in the out-of-plane direction of the active layer 413.

  The mirror layer 412 is configured as a DBR (Distributed Bragg Reflector) mirror. The mirror layer 412 constitutes one of a pair of mirrors essential for the laser light source. An external coupler 416 is used for the other mirror. The external coupler 416 will be described later. The mirror layer 412 emits the laser beam generated in the active layer 413 as described above in the out-of-plane direction of the active layer 413.

  The SHG element 415 converts the oscillation wavelength of the infrared laser beam into a visible laser beam having a half wavelength. This SHG element 415 uses a single crystal substrate of an inorganic nonlinear optical material such as LN (LiNbO 3) or LT (LiTaO 3), for example, forms a stripe-shaped insulating layer periodically by photolithography, and then applies an electric field. The substrate on which the periodic domain-inverted structure is formed is cut into an appropriate size, the surface on which laser light enters and exits is polished, and an antireflection film is further formed.

  As described above, the external coupler 416 constitutes the other of the pair of mirrors essential for the laser light source. As the external coupler 416, for example, a VBG (Volume Bragg Grating) element is used. A VBG element is an optical element that narrows and reflects a laser beam having an oscillation wavelength. In this VBG element, a glass layer such as alkali boroaluminosilicate glass mainly composed of SiO2 is irradiated with ultraviolet rays having a predetermined wavelength, and interference patterns having different refractive indexes are formed in layers in the glass layer. This VBG element uses the formed interference pattern to selectively reflect only the laser light having the oscillation wavelength, and allows visible light generated by the SHG element 415 to pass therethrough.

  In such a laser array 311, when a current is applied to the active layer 413, the laser light generated in the active layer 413 is repeatedly reflected between the mirror layer 412 and the external coupler 416, resonated and amplified, and has a predetermined transmission frequency. Infrared laser light is oscillated. The infrared laser light is converted into visible light having a half wavelength by the SHG element 415, and is output from the external coupler 416 in the out-of-plane direction of the laser array 311.

  Returning to FIG. 3, the laser light source unit 311 </ b> A including the laser light source 41 as described above is connected to the power supply unit 312 via a drive switch 313 as a lighting drive unit.

  The power supply unit 312 is connected to the power supply unit housed in the cabinet 2 of the rear projector 1 described above, and supplies a constant current to the light source device 31 under the control of the control unit 4.

  The drive switch 313 is electrically connected to the control unit 4 and is driven by the control of the control unit 4. That is, the drive switch 313 is controlled to be turned ON and OFF under the control of the control unit 4, and electrically connects the predetermined laser light source unit 311A and the power supply unit 312 in the ON state. Then, when the predetermined laser light source unit 311A and the power supply unit 312 are connected, a current flows from the above-described conducting means to the laser light source 41, and laser light having a predetermined wavelength is oscillated from the laser light source 41.

Further, the duty ratio of the drive time for driving the individual drive switch 313 is about 20% because there are five drive switches here, and the ON state is maintained by this drive time ratio, and from the laser light source unit 311A. Laser light is emitted.
These drive switches 313 are driven by switching sequentially at drive time intervals under the control of the control unit 4. In other words, while one drive switch 313 is set to the ON state and driven, the other drive switch 313 is maintained in the OFF state. Thereafter, when a predetermined drive time has elapsed and the one drive switch 313 is turned off under the control of the control unit 4, one of the other drive switches 313 is set to the ON state. Further, when the switching of the drive switch 313 is completed, the drive switch 313 that is driven first is set to the ON state again. In this manner, the control unit 4 sequentially switches the drive switch 313 to sequentially drive the laser light source unit 311A to light up.

(Operational effects of the first embodiment)
Next, the operation and effect of the light source device 31 of the projector unit 3 of the rear projector 1 according to the present embodiment will be described.

  The control unit 4 of the light source device 31 controls the laser array by controlling the ON / OFF driving state of the drive switch 313 when an operation signal indicating that the laser light is emitted from the light source device 31 is recognized by a user operation or the like. Laser light is emitted from 311. Specifically, the control unit 4 drives only one drive switch 313 among the laser light source units 311A in the laser array 311 and energizes the laser light source unit 311A connected to the driven drive switch 313. . As a result, a current flows from the conducting means to the laser light source 41, and laser light having a predetermined wavelength is oscillated. The output of the oscillated laser light is amplified by the laser light source 41, passes through the SHG element 415, undergoes wavelength conversion, and is emitted from the external coupler 416 to the outside.

  Then, the control unit 4 drives the one drive switch 313 for a predetermined drive time, and then switches the drive switch 313 to the OFF state and simultaneously switches one of the other drive switches 313 to the ON state. Thereafter, the control unit 4 performs the same control as described above, and periodically switches the ON / OFF state of the drive switch 313 sequentially at drive time intervals. Accordingly, the laser light source units 311A of the laser array 311 are sequentially energized, and laser light is sequentially emitted from these laser light source units 311A.

  For this reason, in the light source device 31 as described above, since a current is supplied to each laser light source unit 311A, a current required for emitting laser light having a predetermined output can be reduced. Therefore, the power consumption when driving the light source device 31, the projector unit 3, and the rear projector 1 can also be reduced.

  Further, since a large-sized power supply device that generates high output power is not required, the projector unit 3 and the rear projector 1 can be reduced in size. Further, since the laser light source unit 311A is sequentially driven by sequentially switching the ON / OFF state of the drive switch 313, the laser light can be continuously emitted from the laser array 311. On the other hand, the time utilization efficiency can be improved.

  Further, the light source device 31 includes a red light source device 31R, a blue light source device 31B, and a green light source device 31G. Each of the color light source devices includes a laser array 311 that emits laser light corresponding to each color. For this reason, it is possible to easily output, for example, red laser light, blue laser light, and green laser light from each color light source device 31 simultaneously, or to select and emit laser light of any one of the three colors. Can do.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. In the following description, the same structure and the same member as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified. FIG. 5 is a diagram showing a schematic configuration of the optical system of the projector unit 3A according to the second embodiment. FIG. 6 is a schematic diagram illustrating a schematic configuration of a drive circuit of the light source device according to the second embodiment.

[Configuration of projector unit]
In the second embodiment, a so-called DLP (Digital Light Processing) projector is used as the projector unit 3A. As shown in FIG. 5, the projector unit 03A includes a light source device 36, a DMD (Digital Micromirror Device: trademark of Texas Instruments) 37, and a projection lens 35.

  As shown in FIG. 5, the light source device 36 includes a red light source device 36R that emits red laser light, a green light source device 36G that emits green laser light, and a blue light source device 36B that emits blue laser light. Each of these color light source devices 36R, 36G, and 36B is provided so as to be connectable to a power supply unit 312 via a light source drive switch 314 as a drive device, as shown in FIG. Similar to the drive switch 313 of the first embodiment, these light source drive switches 314 are switched between ON / OFF states under the control of the control unit 4, and in the ON state, the corresponding light source devices 36 and power supply units are switched. 312 is electrically connected.

  The DMD 37 is formed on, for example, a semiconductor, is driven at a high speed under the control of the control unit 4, and reflects the laser light having different wavelengths emitted from the light source device 36 to the projection lens 35.

  The projection lens 35 projects the incident laser light as image light L toward the reflection mirror 5 as in the first embodiment.

  In the projector unit 3A of the second embodiment as described above, when one light source drive switch 314 is driven and is in the ON state, the control unit 4 turns off the other light source drive switch 314 and performs a predetermined drive. After the elapse of time, the one light source drive switch 314 is turned off, and one of the other light source drive switches 314 is turned on. In this way, the control unit 4 sequentially switches the ON / OFF state of the light source drive switch 314 to sequentially drive the color light source devices 36 to light them.

  For this reason, since each color light source device 36R, 36G, 36B is independently pulse-driven, each color light source device 36R, 36G, 36B can be pulse-driven with a small current, and the light source device 36 is driven. Therefore, power consumption can be reduced. Further, a large-sized power supply device that generates high output power is not required, and the projector unit 3A and the rear projector 1 can be downsized. Furthermore, since the respective color light source devices 36R, 36G, and 36B are sequentially pulse-driven, the temporal utilization efficiency can be improved.

  In addition, since each color laser beam is emitted from the light source device 36, a color wheel filter such as a conventional DLP projector, or lenses arranged before and after the color wheel filter are not necessary, and the configuration of the DLP projector is eliminated. Easy to do.

[Third embodiment]
Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a schematic diagram showing a schematic configuration of a drive circuit of the light source device in the third embodiment.

  In the light source device 36 of the second embodiment described above, each light source device 36R, 36G, 36B is sequentially pulse-driven by the light source drive switch 314, whereas in the light source device 36 of the third embodiment. Each of the color light source devices 36R, 36G, and 36B includes a plurality of color laser light source units 311A that are sequentially pulse-driven by a drive switch 313.

  That is, as in the second embodiment, the light source device 36 includes a red light source device 36R that emits red laser light, a green light source device 36G that emits green laser light, and a blue light source device that emits blue laser light. 36B. Each of the color light source devices 36R, 36G, and 36B includes each color laser array 311 that emits laser light corresponding to each color. These laser arrays 311 are composed of a plurality of laser light sources 41 as shown in FIG. 4, and these laser light sources 41 are further divided into groups each including at least one laser light source 41 to form a laser light source unit. 311A is configured.

  These laser light source units 311A are provided so as to be connectable to the power supply unit 312 via the drive switch 313, as in the first embodiment. These drive switches 313 are switched between ON / OFF states under the control of the control unit 4, and electrically connect the corresponding laser light source unit 311 </ b> A and the power supply unit 312 in the ON state.

  In the projector unit 3A of the third embodiment as described above, when one drive switch 313 is driven and is in the ON state, the control unit 4 turns off the other drive switch 313. Then, after a predetermined drive time has elapsed, the one drive switch 313 is turned off, and one of the other drive switches 313 is turned on. In this way, the control unit 4 sequentially switches the drive switch 313 to sequentially drive the laser light source unit 311A in a pulsed manner so as to light cyclically.

  Also in the third embodiment as described above, each of the color light source devices 36R, 36G, and 36B includes a plurality of laser light source units 311A and is controlled by the control unit 4 as in the other embodiments described above. By sequentially switching the drive switch 313, the laser light source unit 311A is sequentially pulse-driven to light cyclically. For this reason, the laser light source 41 of the laser light source unit 311A can be driven with a small current, and the power consumption for driving the light source device 36 can be reduced. In addition, a large-sized power supply device that generates high output power is not required, and the projector unit 3A and the rear projector 1 can be reduced in size, and moreover, time utilization efficiency can be improved.

  Similarly to the second embodiment, since each color laser beam is emitted from the light source device 36, a color wheel filter such as a conventional DLP projector, a lens disposed before and after the color wheel filter, and the like. The configuration of the DLP projector that is not necessary can be simplified.

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a schematic diagram illustrating a schematic configuration of a drive circuit of the light source device according to the fourth embodiment.

  In the light source device 31 of the fourth embodiment, the light source drive switch 314 of the second embodiment and the drive switch 313 of the third embodiment are combined to emit laser light of each color.

  That is, the fourth embodiment includes a red light source device 36R that emits red laser light, a green light source device 36G that emits green laser light, and a blue light source device 36B that emits blue laser light. These color light source devices 36R, 36G, and 36B are provided so as to be connectable to a power supply unit 312 via a light source driving switch 314 as shown in FIG. These light source drive switches 314 are switched between ON / OFF states under the control of the control unit 4, and in the ON state, the corresponding color light source devices 36R, 36G, 36B and the power supply unit 312 are electrically connected.

  Each color light source device 36R, 36G, 36B includes each color laser array 311 for emitting laser light corresponding to each color. These laser arrays 311 are composed of a plurality of laser light sources 41 as shown in FIG. 4, and these laser light sources 41 are further divided into groups each including at least one laser light source 41 to form a laser light source unit. 311A is configured.

  These laser light source units 311A are provided so as to be connectable to the light source drive switch 314 via the drive switch 313. These drive switches 313 are switched between ON / OFF states under the control of the control unit 4, and electrically connect the corresponding laser light source unit 311 </ b> A and the light source drive switch 314 in the ON state.

  In the light source device 36 of the fourth embodiment as described above, the control unit 4 drives the laser light source unit 311A in a pulse manner by the combination of the light source drive switch 314 and the drive switch 313. For example, the control unit 4 sequentially switches the laser light source unit 311A that emits red laser light by sequentially switching the drive switch 313 in the red light source device 36R in a state where the light source drive switch 314 is connected to the red light source device 36R. Pulse drive to light cyclically. Then, after all of the laser light source units 311A of the red light source device 36R are turned on, the light source drive switch 314 is switched to, for example, the green light source device 36G, and the drive switch 313 in the green light source device 36G is sequentially switched. In this way, the laser light source units 311A of the respective colors are sequentially pulse-driven and turned on cyclically.

  By operating as described above, also in the fourth embodiment as described above, the laser light source 41 of the laser light source unit 311A is driven with a small current, as in the first to third embodiments. Can do. In addition, a large-sized power supply device that generates high output power is not required, the projector unit 3 and the rear projector 1 can be downsized, and the time utilization efficiency can be improved.

  In addition, by controlling both the light source drive switch 314 and the drive switch 313 by the control unit 4, the order in which the respective color laser lights are emitted can be easily changed.

[Modification of the embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

  For example, in the first to third embodiments, one drive switch 313 is provided for one laser light source unit 311A, and the laser light source unit 311A is switched by switching the ON / OFF state of these drive switches 313. However, the present invention is not limited to this. For example, as shown in FIG. 8, each of the laser light source units 311A has a terminal, and the drive switch 313 is connected to one of these terminals, so that the laser light source unit corresponding to the connected terminal. It is good also as a structure which sends an electric current to 311A.

  In the second to fourth embodiments, the configuration of the DLP projector unit 3A is illustrated, but the present invention is not limited to this. For example, as in the first embodiment, three light source devices 31 provided facing the side surfaces of the cross dichroic prism may be connected to the light source drive switch 314 and sequentially pulse-driven.

  Further, in the above embodiment, the control unit 4 is provided outside the projector unit 3 and controls the projector unit 3 and the rear projector 1 as a whole. However, the control means for controlling only the drive switch 313 of the light source device 31. May be separately provided in the projector units 3 and 3A.

  In the above embodiment, the laser light source unit 311A that emits each color laser light is provided with one laser light source 41. However, as described above, one laser light source unit 311A includes a plurality of laser light sources 41. May be configured. In this case, the laser light source 41 constituting the laser light source unit 311A is determined according to the output of the emitted laser light and the supplied power. That is, when it is necessary to increase the output of the laser light or when the power supplied from the power supply unit 312 is small, the number of laser light sources 41 constituting one laser light source unit 311A is reduced. On the other hand, when the output of laser light may be weak or when high power can be supplied from the power supply unit, the number of laser light sources 41 per laser light source unit 311A is increased.

  In the above embodiment, the light source devices 31 and 36 constituting the projector unit 3 mounted on the rear projector 1 are exemplified. However, the present invention is not limited to this, and the present invention may be used for other types of projectors such as a front projector. Good.

Although the best configuration for carrying out the present invention has been disclosed in the above description, the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

  The present invention can be used in a light source device that emits laser light and a projector including the light source device.

The side section of the rear projector of a 1st embodiment concerning the present invention. FIG. 2 is a schematic diagram showing an outline of an optical system configured inside a projector unit. The schematic diagram which shows the outline of the drive circuit of a light source device. Sectional drawing which shows typically schematic structure of a laser light source. The schematic diagram which shows the outline of the optical system comprised inside the projector unit in 2nd embodiment. The schematic diagram which shows schematic structure of the drive circuit of the light source device in 2nd embodiment. The schematic diagram which shows schematic structure of the drive circuit of the light source device in 3rd embodiment. The schematic diagram which shows schematic structure of the drive circuit of the light source device in 4th embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 3, 3A ... Projector unit as a projector, 4 ... Control unit which comprises a part of a lighting drive part and a drive device, 31, 36 ... Light source device, 32 ... Liquid crystal panel which comprises a light modulation element, 33 ... Light modulation element 34... Cross dichroic prism as color synthesis optical system, 35. Projection lens as projection optical system, 41... Laser light source, 311... Laser array, 311 A. Drive switch constituting drive unit, 314... Light source drive switch constituting drive device, 413... Active layer, 415... SHG element as wavelength conversion element.

Claims (4)

A laser array in which a plurality of laser light sources are arranged in a matrix, a wavelength conversion element that is provided facing the laser light emission surface of the laser array and converts the wavelength of the laser light emitted from the laser array; A light source device including a lighting drive unit that performs lighting driving of the laser array,
The light-emitting device is characterized in that the lighting drive unit sequentially pulse-drives each of the groups set by dividing a plurality of laser light sources in the laser array to light cyclically. Combining multiple light source devices that emit laser light of different wavelengths, multiple light modulation elements that modulate laser light emitted from each light source device according to image information, and modulated light converted by each light modulation device A projector that includes a color combining optical system that performs a projecting optical system that magnifies and projects the combined light,
The light source device includes a laser array in which a plurality of laser light sources are arranged in a matrix, and a wavelength for converting the wavelength of the laser light emitted from the laser array provided opposite to the laser light emission surface of the laser array. A conversion element, and a lighting driving unit that performs lighting driving of the laser array,
The projector is characterized in that the lighting drive unit sequentially pulse-drives each of a group set by dividing a plurality of laser light sources in the laser array to cyclically light up the projector. Combining multiple light source devices that emit laser light of different wavelengths, multiple light modulation elements that modulate laser light emitted from each light source device according to image information, and modulated light converted by each light modulation device A projector that includes a color combining optical system that performs a projecting optical system that magnifies and projects the combined light,
The light source device includes a laser array in which a plurality of laser light sources are arranged in a matrix, and a wavelength for converting the wavelength of the laser light emitted from the laser array provided opposite to the laser light emission surface of the laser array. A conversion element,
A projector comprising: a driving device that sequentially pulses the plurality of light source devices to light them cyclically. The projector according to claim 3, wherein
The light source device includes a lighting drive unit that sequentially pulsates and cyclically lights each of the groups set by dividing a plurality of laser light sources in the laser array,
A projector characterized in that a combination of groups in an arbitrary laser array is cyclically lit by a combination of switching of the driving device and each lighting driving unit.

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