JP2007300009A - Laser light source device and laser display device having the same - Google Patents

Abstract

Provided is a laser light source device capable of reducing the size and weight of a laser light source and enabling temperature control with a minimum temperature control element.
A laser light source apparatus according to the present invention includes a red laser light source 2R that generates red laser light, a green laser light source 2G that generates green laser light, a blue laser light source 2B that generates blue laser light, A heat radiation substrate 3 on which the laser light sources of these colors are mounted in common is provided. Thus, by mounting the laser light sources of the respective colors on a common heat dissipation substrate, the laser light sources can be integrated, reduced in size and weight. In addition, by providing the temperature control element P1 for controlling the temperature of the heat dissipation substrate 3, the temperature of each color laser light source can be adjusted with one temperature control element.
[Selection] Figure 2

Description

  The present invention relates to an RGB (red green blue) laser light source device whose temperature is controlled to obtain an appropriate wavelength, and a laser display device including the same.

  The monochromatic RGB laser light source generally includes (1) a semiconductor laser, (2) a laser resonator composed of a wavelength conversion element, a solid-state laser crystal that oscillates its fundamental wave, and a semiconductor laser that excites the solid-state laser crystal, (3) Three types of laser resonators composed of a wavelength conversion element and a semiconductor laser that oscillates its fundamental wave are used.

  In particular, in recent years, development of portable laser display devices called mobile displays, pocket displays, microdisplays, and the like has been promoted. These laser display devices are required to have a small, light, low power consumption and low cost RGB laser light source. A semiconductor laser is used as a red laser light source, and a wavelength conversion element and its fundamental wave are used as a green laser light source. A laser resonator composed of a solid-state laser crystal that oscillates and a semiconductor laser that excites a solid-state laser is used, and a semiconductor laser is generally used as a blue laser light source.

  As a green laser light source, a laser resonator composed of a wavelength conversion element and a semiconductor laser that oscillates its fundamental wave has already been developed, but has not yet been widely used in terms of cost. Green semiconductor lasers are being developed, but have not yet been put into practical use in terms of oscillation temperature and output.

  A configuration of a conventional RGB laser light source will be described.

  FIG. 10 shows a configuration of a laser light source 100 described in Patent Document 1 below, which includes a wavelength conversion element, a solid-state laser crystal that oscillates its fundamental wave, and a semiconductor laser that excites the solid-state laser crystal. Yes. In FIG. 10, 101 is an Nd: YAG crystal as a solid laser crystal, 101a is a mirror formed on the end face of the solid laser crystal 101, 102 is a KNbO3 crystal which is a wavelength conversion element, 103 is a spherical laser mirror, and 104 is a solid laser crystal. This is a semiconductor laser that excites 101.

  The laser light source 100 having the above-described configuration oscillates a laser beam having a wavelength of 946 nm by exciting the solid-state laser crystal 101 with the semiconductor laser 104, and converts the wavelength of the laser light into ½ by the wavelength conversion element 102. The emitted light (blue) 105 of 473 nm is generated. Reference numeral 106 denotes a Peltier element (temperature control element) that adjusts the temperature of the wavelength conversion element 102 for phase control that maximizes the wavelength conversion efficiency.

  By changing the setting of the light reflection wavelength of the laser mirror, it is also possible to oscillate laser light having a wavelength of 1064 nm with a solid-state laser crystal and generate emitted light (green) with a wavelength of 532 nm by a wavelength conversion element. For example, FIG. 11 shows a configuration of a laser light source 110 described in Patent Document 2 below. In FIG. 11, 111 is a semiconductor laser that generates laser light having a wavelength of 809 nm, 112 is a laser mount, 113 is an Nd: YAG crystal as a solid-state laser crystal provided with a laser mirror coating 114, and 115 is a wavelength conversion element. A crystal, 116 is a mirror provided with a laser mirror coating 117, and 118 is a filter that selectively transmits light having a wavelength of 532 nm.

  Here, in order to maximize the excitation efficiency of the solid-state laser crystal 113, the wavelength of the semiconductor laser 111 needs to match the absorption peak of the solid-state laser crystal 113. For this reason, in the laser light source 110 having the above-described configuration, the laser mount 112 is mounted on a temperature control unit (not shown) incorporating a Peltier element, and the temperature is controlled so as to keep the emitted light of the semiconductor laser 111 at a wavelength of 809 nm. .

  On the other hand, FIG. 12 shows an example of the configuration of a laser display system (see Patent Document 3 below). This laser display system includes an RGB laser light source 120 including a red laser device 121R that emits red laser light 122R, a green laser device 121G that emits green laser light 122G, and a blue laser device 121B that emits blue laser light 122B. It has. The RGB laser light source 120 reflects the laser beams 122R, 122G, and 122B of the respective colors with the reflecting plates 123R, 123G, and 123B and combines them to generate a single light beam. The generated single light beam is projected onto the screen 125 via the laser control system 124, and a predetermined color image is displayed on the screen 125.

JP-A-5-11295 JP-A-5-243660 JP 2004-139081 A

As described above, semiconductor lasers, solid-state laser crystals, and wavelength conversion elements are used for conventional RGB laser light sources. In order to obtain the optimum color gamut for the red and blue semiconductor lasers, and to maximize the pumping efficiency of the semiconductor laser for pumping the solid-state laser crystal, each semiconductor laser was kept within the proper range. It is necessary to adjust the temperature so that
On the other hand, the solid laser crystal has a temperature dependency in the absorption efficiency and the wavelength conversion element has a temperature dependency in the conversion efficiency, and the temperature needs to be optimally controlled to obtain the maximum efficiency.

  For example, a red laser light source includes a semiconductor laser, a green laser light source includes a wavelength conversion element, a solid-state laser crystal that oscillates its fundamental wave, a laser resonator that includes a semiconductor laser that excites the solid-state laser, and a blue laser. As a display laser light source device using a semiconductor laser as a light source, at least a temperature control element for semiconductor lasers of RGB colors and a temperature control element commonly used for a solid-state laser crystal and a wavelength conversion element are used. Four temperature control elements are required.

  Therefore, the RGB laser light source is complicated and large with a temperature control function, and is conventionally manufactured as a single-color laser device for each color, and is used as a laser light source for a display by combining them. Therefore, the laser light source as a whole has a problem that it is very large, complicated and expensive, and uses a large number of temperature control elements, resulting in high power consumption.

  The present invention has been made in view of the above-mentioned problems, and can provide a laser light source device capable of reducing the size and weight of a laser light source and capable of temperature control with a minimum temperature control element, and a laser display device including the same. The issue is to provide.

  In solving the above problems, a laser light source device of the present invention includes a red laser light source that generates red laser light, a green laser light source that generates green laser light, a blue laser light source that generates blue laser light, and these And a heat dissipation substrate on which the laser light sources of the respective colors are mounted in common. Thus, by mounting the laser light sources of the respective colors on a common heat dissipation substrate, the laser light sources can be integrated, reduced in size and weight.

  In addition, the laser light source device of the present invention includes a temperature control element for controlling the temperature of the heat dissipation substrate, so that the temperature of each color laser light source can be adjusted with one temperature control element.

  The red laser light source and the blue laser light source can be composed of a single semiconductor laser. The green laser light source includes a wavelength conversion element, a solid-state laser crystal that oscillates its fundamental wave, and a semiconductor laser that excites the solid-state laser crystal. It can comprise with the laser resonator containing. In this case, the temperature control element is used as the first temperature control element for temperature control of the heat dissipation substrate, and the wavelength conversion element of the green laser light source is provided by a second temperature control element different from the first temperature control element. The temperature of the solid laser crystal is controlled. Thereby, the optimization of the oscillation wavelength of the semiconductor laser constituting the laser light source of each color and the optimization of the absorption efficiency of the solid laser crystal and the conversion efficiency of the wavelength conversion element can be realized by only two temperature control elements. .

  The first and second temperature control elements are not particularly limited, but elements that can be electrically controlled, such as Peltier elements, are suitable. In this case, the first temperature control element controls the temperature of the heat dissipation substrate in an endothermic state, and the second temperature control element controls the temperature of the wavelength conversion element and the solid-state laser crystal in a heat generation state, thereby controlling the temperature. It is possible to reduce the power consumption required.

  The laser light source device according to the present invention configured as described above can be used as a laser light source of a laser display provided with a laser control system that modulates and scans laser light of each color. In addition, the present invention can be applied to various laser apparatuses that use laser beams of RGB colors, such as biochemical analysis apparatuses.

  As described above, according to the present invention, the RGB laser light source can be reduced in size and weight, and temperature control can be performed with a minimum temperature control element.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 4 show the configuration of an RGB laser light source device 1 according to an embodiment of the present invention. FIG. 1 is a plan view, FIG. 2 is a side view, FIG. 3 is an overall perspective view, and FIG. It is a perspective view. In the figure, the direction parallel to the laser optical axes of each RGB color is the X axis, the arrangement direction of the laser optical axes of each color is the Y axis, and the direction perpendicular to these X and Y axes (height direction) Is the Z axis.

  The RGB laser light source device 1 of the present embodiment includes a red laser light source 2R, a green laser light source 2G, a blue laser light source 2B, and a heat dissipation substrate (commonly mounted) with the laser light sources 2R, 2G, and 2B of these colors. Substrate) 3.

  The heat dissipation substrate 3 is made of a metal substrate configured as a heat sink. The upper surface of the heat dissipation substrate 3 is a flat mounting surface 3a on which the laser light sources 2R, 2G, and 2B of the respective colors are mounted. A first temperature control element P1 is attached to the lower surface of the heat dissipation substrate 3, and the temperature of the heat dissipation substrate 3 is controlled by the first temperature control element P1.

  The first temperature control element P1 is set to a temperature at which the laser light generated by the semiconductor lasers 4R, 4G, and 4B mounted on the laser light sources 2R, 2G, and 2B of the respective colors can obtain an oscillation wavelength in an appropriate range. The temperature of the heat dissipation substrate 3 is controlled. The first temperature control element P1 is a Peltier element.

  The heat dissipation substrate 3 is disposed on the heat insulating plate 25. The heat insulating plate 25 is formed with an opening 25a for accommodating the first temperature control element P1. A front wall 25b is erected at the front end portion of the heat insulating plate 25, and the front surface of the heat radiating substrate 3 is aligned with the inner surface side of the front wall 25b so that the relative position of the heat radiating substrate 3 with respect to the heat insulating plate 25 is increased. It is determined. The heat insulating plate 25 is installed on a metal base substrate 26 that functions as a heat sink. The heat dissipation substrate 3, the heat insulating plate 25, and the base substrate 26 are integrally coupled by four bolt members 20 at the respective four corner positions.

  The red laser light source 2R includes a semiconductor laser 4R that generates red laser light having a wavelength of about 635 nm, a collimator lens 10R that collimates the red laser light generated by the semiconductor laser 4R, and a prism 11R that adjusts the beam emission position. Have.

  The blue laser light source 2B includes a semiconductor laser 4B that generates blue laser light having a wavelength of about 445 nm, a collimator lens 10B that collimates the blue laser light generated by the semiconductor laser 4B, and a prism 11B that adjusts the beam emission position. Have.

The green laser light source 2G is a laser including a wavelength conversion element 5 made of, for example, a KTP crystal, a solid-state laser crystal 6 made of, for example, Nd: YVO ₄ that oscillates its fundamental wave, and a semiconductor laser 4G that excites the solid-state laser crystal 6. It has a resonator. The pumping semiconductor laser 4G has an oscillation wavelength of 808.6 nm at 29 ° C. (807.4 nm at 25 ° C.), and light having a wavelength of 1064 nm pumped by the solid-state laser crystal 6 is amplified in the resonator, and is converted into a wavelength conversion element. 5, the frequency is doubled to generate a green laser beam having a wavelength of 532 nm. The generated green laser light is converted into collimated light while the beam size is expanded by the beam expander 12. Then, the polarization angle is adjusted by the half-wave plate 14. The light having a wavelength of 1064 nm leaking from the resonator is cut by an IR (infrared) cut filter 13.

  The wavelength conversion element 5 and the solid-state laser crystal 6 are formed of a combination crystal that is bonded and integrated through an adhesive, and a predetermined laser mirror coating is applied to both end faces thereof. That is, the one end face of the combination crystal facing the pumping semiconductor laser 14G is provided with a laser mirror coating that transmits light having a wavelength of 808.6 nm (807.4 nm) and reflects light having a wavelength of 1064 nm, and the other end face of the combination crystal. A laser mirror coating is applied to transmit light having a wavelength of 532 nm and reflect light having a wavelength of 1064 nm.

  The combination crystal composed of the wavelength conversion element 5 and the solid-state laser crystal 6 is disposed on the second temperature control element P2 via the substrate 15 on which the thermistor is mounted, and this second temperature control. The temperature of the combination crystal is controlled by the element P2 (29 ° C. or 25 ° C. in this example). The second temperature control element P2 controls the temperature of the solid laser crystal 6 so that the absorption efficiency of the solid-state laser crystal 6 and the conversion efficiency of the wavelength conversion element 5 can be tuned to the maximum. The second temperature control element is composed of a Peltier element.

  On the other hand, the red semiconductor laser 4R, the blue semiconductor laser 4B, and the pumping semiconductor laser 4G are each controlled to a common temperature on the heat dissipation substrate 3 whose temperature is controlled by the first temperature control element P1. The set temperature of the heat dissipation substrate 3 is set in consideration of the oscillation efficiency or excitation efficiency of these semiconductor lasers. In this example, the temperature is set to 29 ° C. or 25 ° C. Note that the temperature controlled by the first temperature control element P1 is monitored by a thermistor disposed close to the pumping semiconductor laser 4G.

  The laser light sources 2R, 2G, and 2B for the respective colors are mounted on the dedicated heat-transfer laser bases 8R, 8G, and 8B, and the heat dissipation substrate 3 is connected via the laser bases 8R, 8G, and 8B. Mounted on the top surface (mounting surface).

  The red laser base 8R is provided with a laser mount 9R that supports the semiconductor laser 4R, and optical elements such as a collimator lens 10R and a prism 11R are mounted via predetermined support members. On the laser base 8R, the red laser beam (R) has its beam optical axis tilt angle and divergence angle adjusted by adjusting the optical axes of the collimator lens 10R and the prism 11R.

  The blue laser base 8B is provided with a laser mount 9B that supports the semiconductor laser 4B, and optical elements such as a collimator lens 10B and a prism 11B are mounted via predetermined support members. For the blue laser beam (B), the tilt angle and divergence angle of the beam optical axis are adjusted with high accuracy by adjusting the optical axes of the collimator lens 10B and the prism 11B on the laser base 8B.

  The green laser base 8G includes a pumping semiconductor laser 4G, a wavelength conversion element 5, and a solid-state laser crystal 6 together with optical elements such as an expander lens 12, an IR (infrared) cut filter 13, and a half-wave plate 14, and a predetermined number. It is mounted via a support member. The green laser beam (G) has a tilt angle and a divergence angle of the beam optical axis adjusted with high accuracy by adjusting the optical axis of the beam expander 12 on the laser base 8G.

  The collimation adjustment and the optical axis angle adjustment of each RGB laser light are performed while moving the beam profiler on the optical rail and measuring the beam size and optical axis position at each distance from the light source.

  The red laser base 8R, the green laser base 8G, and the blue laser base 8B are respectively mounted on predetermined regions of the mount surface 3a of the heat dissipation substrate 3 through spacers 7R, 7G, and 7B. The red laser base 8R and the blue laser base 8B are integrally fixed to the mount surface 3a by two screw members 16, and the green laser base 8G is integrally fixed to the mount surface 3a by four screw members 16. Has been.

  The spacers 7R, 7G, and 7B are made of a metal plate having a constant thickness that defines the height of the laser optical axis of each color with respect to the mount surface 3a, as will be described later.

  According to the present embodiment, by mounting the red semiconductor laser light source 2R, the green laser light source 2G, and the blue laser light source 2B on the common heat dissipation substrate 3 that serves as a heat sink, it is possible to integrate the laser light sources of RGB colors. Thus, the laser light source device 1 can be reduced in size and weight. Further, it is possible to realize appropriate temperature control of the heat dissipation substrate 3 by the first temperature control element P1. As a result, the oscillation wavelengths of the semiconductor lasers 4R, 4G, and 4B of the laser light sources of the respective colors can be kept in an appropriate range.

  On the other hand, the laser resonator composed of the solid-state laser crystal 6 and the wavelength conversion element 5 for generating the green laser light is controlled by the second temperature control element P2 arranged on the upper side of the heat dissipation substrate 3, so that the solid-state laser High absorption efficiency of the crystal 6 and high conversion efficiency of the wavelength conversion element 5 can be obtained at the same time. In particular, by controlling the temperature of the solid-state laser crystal 6 and the wavelength conversion element 5 in a heat generation state (heating state) with the second temperature control element P2 made of a Peltier element, the cooling substrate 3 has a cooling effect. As a result, the power consumption of the first temperature control element P1 that cools the heat dissipation substrate 3 that rises in temperature due to heat generated by the semiconductor laser can be reduced.

  Also, a semiconductor laser as a red laser light source, a laser resonator comprising a wavelength laser as a green laser light source, a solid-state laser crystal that oscillates its fundamental wave, and a semiconductor laser that excites the solid-state laser crystal, and a semiconductor laser as a blue laser light source Conventionally, RGB laser light sources using the above are supplied as individual modules, and at least four temperature control elements are required for optimal temperature control. On the other hand, the RGB laser light source device 1 of this embodiment includes a first temperature control element P1 that controls the temperatures of the solid-state laser crystal excitation semiconductor laser 4G, the red semiconductor laser 4R, and the blue semiconductor laser 4B to a common temperature. The two temperature control elements, the second temperature control element P2 that controls the temperature of the solid-state laser crystal 6 and the wavelength conversion element 5 to a common temperature, enable optimal temperature control, and the optimal color gamut of red and blue The maximum excitation efficiency of the solid-state laser crystal by the semiconductor laser, the maximum absorption efficiency of the solid-state laser crystal, and the maximum conversion efficiency of the wavelength conversion element can be obtained.

  Furthermore, by integrating the laser light source of each color and minimizing the temperature control element, the component cost of the RGB laser light source device can be reduced, the temperature control power can be reduced, and the size and weight can be reduced. It is extremely effective when used for an RGB laser light source of a portable laser display device called a pocket display, a micro display or the like, and can also be applied to a biochemical analysis device using a similar RGB laser light source.

  Next, an optical axis adjustment mechanism in the RGB laser light source device 1 having the above-described configuration will be described.

  The laser light source device 1 includes an optical axis adjustment mechanism that can adjust the laser optical axis with respect to the mount surface 3a by moving the laser light sources 2R, 2G, and 2B of the respective colors relative to the heat dissipation substrate 3. This optical axis adjusting mechanism is for emitting laser optical axes of RGB colors in parallel and at the same height position, and a laser light source whose optical axis is controlled with high accuracy in units of laser bases 8R, 8G, and 8B. A mechanism for aligning 2R, 2G, and 2B on the heat dissipation substrate 3 in the Y and Z axis directions with high accuracy is provided.

  FIG. 5A is a cross-sectional view of the bottom structure of the laser bases 8R, 8G, and 8B as viewed from the upper surface side. FIG. 5B is a plan view showing the configuration of the mount surface 3a of the heat dissipation substrate 3 together with the spacers 7R, 7G, and 7B.

  A pair of reference pins 18R, 18G, and 18B are erected on the mount surface 3a of the heat dissipation substrate 3 corresponding to the mounting positions of the laser light sources 2R, 2G, and 2B (FIG. 4). The pair of reference pins 18R, 18G, and 18B of these colors are arranged to face each other in the Y-axis direction.

  On the other hand, guide grooves 17R, 17G, and 17B that fit into the reference pins 18R, 18G, and 18B are formed on the bottoms of the laser bases 8R, 8G, and 8B of the respective colors, and the guide shafts 17R, 17G, and The laser bases 8R, 8G, and 8B are configured to be relatively movable in the Y-axis direction with respect to the mount surface 3a by the fitting action of 17B and the reference pins 18R, 18G, and 18B.

  The laser bases 8R, 8G, and 8B are formed with insertion holes 19R, 19G, and 19B for eccentric drivers used when the laser bases 8R, 8G, and 8B are moved in the Y-axis direction along the mount surface 3a, respectively. Has been. On the other hand, the mounting surface 3a has engagement holes 21R, 21G that engage with the rotational axis of the eccentric driver corresponding to the positions where the insertion holes 19R, 19G, 19B of the laser bases 8R, 8G, 8B are formed. , 21B are formed (FIG. 4).

  6A and 6B show a relative position adjustment process of the laser base 8 (8R, 8G, 8B) with respect to the mount surface 3a. As shown in the figure, the eccentric driver 30 is inserted into the insertion hole 19 (19 R, 19 G, 19 B) of the laser base 8, and the protrusion 31 at the tip of the eccentric driver 30 is engaged with the engagement hole 21. Then, by rotating the eccentric driver 30 with the protrusion 31 as the rotation center, the outer periphery of the eccentric driver 30 and the inner wall of the insertion hole 19 come into contact with each other, and the guide grooves 17R, 17G, 17B and the reference pins 18R, 18G, 18B The laser base 8 is moved in the a direction or the b direction according to the rotation direction of the eccentric driver 30 by the configured linear guide mechanism. Therefore, the amount of linear movement of the laser base 8 can be adjusted by adjusting the amount of rotation of the eccentric driver 30.

  In the present embodiment, in the laser bases 8R, 8G, and 8B of the respective colors, the screw holes 22 into which the screw members 16 for coupling to the heat radiating substrate 3 are inserted slightly to allow movement adjustment of the laser base. Although it is formed in a long hole shape, it may be a perfect circle as long as it has a certain degree of play.

  Further, the spacers 7R, 7G, and 7B interposed between the laser bases 8R, 8G, and 8B and the mount surface 3a have predetermined plate thicknesses for adjusting the optical axis height of each color with respect to the mount surface 3a. It is formed with. The spacers 7R, 7G, and 7B include an engagement hole 21 formed in the mount surface 3a, an opening for exposing the screw holes 23R, 23G, and 23B to be screwed with the screw member 16, and reference pins 18R, 18G, Openings for inserting 18B are respectively formed.

  Next, a method for adjusting the optical axes of the laser light sources 2R, 2G, and 2B for RGB colors will be described.

  First, the red laser light source 2 </ b> R, the green laser light source 2 </ b> G, and the blue laser light source 2 </ b> B are respectively mounted on predetermined regions of the mount surface 3 a of the heat dissipation substrate 3. At this time, spacers 7R, 7G, and 7B are interposed in order to adjust a predetermined optical axis height. Of course, the thickness of these spacers may be different for each color, or a plurality of the spacers may be used in an overlapping manner. As a result, the optical axes of the laser light sources are adjusted in the vertical direction with respect to the mount surface 3a, and the optical axes of the RGB colors match the predetermined optical axis height indicated by LH in FIG.

  The laser light sources 2R, 2G, and 2B of the respective colors are temporarily fixed by the screw member 16 on the mount surface 3a. Thereafter, the optical axis interval of each laser light source is adjusted. This adjustment is performed by translating the laser bases 8R, 8G, and 8B in the Y-axis direction using the eccentric driver 30 described with reference to FIG. Thereby, the optical axis of each laser light source is adjusted in a direction parallel to the mount surface 3a, and is matched with a predetermined optical axis interval. After the optical axis adjustment, the laser light sources 2R, 2G, and 2B are integrally fixed on the mount surface 3a by fastening the screw member 16.

  The optical axis interval adjustment may be performed by adjusting the red and blue optical axis positions with reference to the optical axis of the green laser beam, for example. In this case, the position of the green laser optical axis is initially adjusted so as to fall within an appropriate range from a reference surface S (see FIGS. 1 to 3) provided on one side surface of the heat dissipation substrate 3.

  As described above, fine adjustment of the optical axis of the laser light sources 2R, 2G, and 2B of RGB colors is performed on the mount surface 3a. According to the present embodiment, since the optical axes of the RGB colors can be easily translated on the common heat radiating substrate 3, the optical axes between the colors can be adjusted with high accuracy. Further, by using the eccentric driver 30 for this optical axis adjustment, the optical axis position can be adjusted with high resolution.

  In particular, in display devices and biochemical analyzers, it is required to adjust the optical axis position and optical axis angle of a laser with extremely high accuracy. Conventionally, the RGB laser light source uses a combination of individual independent devices, and adjustment of the optical axis position between the RGB lasers is performed by optical parts such as mirrors and prisms, so that workability is poor. Complicated work and high cost were problems. On the other hand, according to the present embodiment, it is possible to supply the RGB laser light source device 1 as an integrated RGB laser light source device 1 in which the optical axes of the RGB laser beams are aligned with high accuracy. It is extremely effective when used as a light source.

  FIG. 7 shows a schematic configuration of a laser display device having the above-described laser light source device 1 as a light source. Here, an image display system using a GLV (Grating Light Valve), which is a one-dimensional reflective display device, will be described as an example of the laser display device 40.

  As shown in FIG. 7, the laser display device 40 includes an RGB laser light source device 1, an illumination lens 42 that converts light emitted from the laser light source device 41 into plate-like light, and light modulation (diffraction) made up of a GLV device. A projection lens 44 having a built-in element 43, a filter that passes only the diffracted light by the light modulation element 43, and a scanning mirror 45 that projects the light that has passed through the projection lens 44 onto a screen 46 are provided. The light modulation element 43 is provided separately for each of the RGB laser beams and modulates the light based on the positional relationship of the microribbons when irradiated with the laser beams, thereby projecting colors and images. Made.

Example 1
As in the above-described embodiment, the power consumption required for temperature control of the laser light source device 1 according to the present invention including the first and second two temperature control elements P1 and P2, and RGB using the four temperature control elements. The power consumption required for temperature control of a laser light source device having a conventional structure in which the temperature of each laser unit was individually controlled was compared. The result is shown in FIG.

The temperature control element is a Peltier element. In the present embodiment, the first temperature control element P1 for RGB laser base is a Peltier element (model number 9500/035/040, Qcmax: 10 W) manufactured by Ferrotec Corporation, which is solid. The second temperature control element P2 for the laser crystal and the wavelength conversion element was a Peltier element (model number 9500/007/012, Qcmax: 0.63 W) manufactured by Ferrotec.
Further, in the laser light source device having a conventional structure shown as a comparative example, the Peltier element for the red laser base and the blue laser base is a Peltier element manufactured by Ferrotec Corporation (model number 9501/017/040, Qcmax: 5.1 W) and green. The Peltier device for laser base (excitation laser) is a Peltier device manufactured by Ferrotec (model number 9500/035/040, Qcmax: 10 W), and the Peltier device for solid laser crystal and wavelength conversion device is manufactured by Ferrotech. A Peltier element (model number 9500/007/012, Qcmax: 0.63 W) was used.

  In this embodiment, the power required to control the temperature of the solid-state laser crystal and the wavelength conversion element to 25 ° C. is 0.026 W, the power required to control the RGB laser base to 25 ° C. is 2.117 W, and the solid-state laser The total power required to control the crystal, the wavelength conversion element, the pumping semiconductor laser, the blue semiconductor laser, and the red semiconductor laser to an appropriate temperature was 2.143 W.

  On the other hand, when the temperature of the base of each semiconductor laser having the conventional structure according to the comparative example is controlled by a dedicated Peltier element, the power required for temperature control of the red semiconductor laser 2 to 25 ° C. is 0.31 W, and the pumping semiconductor The power required to control the temperature of the laser to 25 ° C. is 1.809 W, the power required to control the temperature of the blue semiconductor laser to 25 ° C. is 1.056 W, these power and the solid-state laser crystal and the wavelength conversion element The total power consumption including the temperature control power was 3.201 W.

  From the above results, in this embodiment, the temperature control power is reduced by 33.1% of the conventional structure. An RGB laser light source having a conventional structure is a combination of individual devices, and the configuration size of each individual device is larger than that of each RGB laser unit of the embodiment of the invention, so that it is necessary for an actual conventional RGB laser light source. The temperature control power becomes a larger value.

(Example 2)
Next, the power consumption required for temperature control was compared based on the results of experiments performed by changing the set temperatures of the first and second temperature control elements P1 and P2 in the above-described embodiment. The result is shown in FIG.

  The temperature control elements used in the experiment are all Peltier elements, and the first temperature control element P1 for RGB laser base is a Peltier element (model number 9500/035/040, Qcmax: 10 W) manufactured by Ferrotec Co., Ltd. The second temperature control element P2 for the crystal and wavelength conversion element was a Peltier element (model number 9500/007/012, Qcmax: 0.63 W) manufactured by Ferrotec.

  The power required to control the temperature of the solid-state laser crystal and the wavelength conversion element to 29 ° C. is 0.018 W (heating) when lighted at a room temperature of 25 ° C. with an excitation laser output of 500 mW, a blue laser output of 100 mW, and a red laser output of 100 mW. ), The power required to control the RGB laser base to 29 ° C. was 0.296 W. The total power required to control the solid-state laser crystal, the wavelength conversion element, the pumping semiconductor laser, the blue semiconductor laser, and the red semiconductor laser to an appropriate temperature was 0.314 W.

  Conventionally, in general, the temperature dependence of a solid-state laser crystal, a wavelength conversion element, an excitation semiconductor laser, and a monochromatic semiconductor laser is optimal at about 25 ° C. where absorption efficiency, conversion efficiency, excitation efficiency, and oscillation wavelength are close to room temperature, respectively. Designed to be In this example, when the temperature of the solid-state laser crystal and the wavelength conversion element is controlled, the temperature-dependent design is adjusted to 29 ° C., which switches from the cooling state (endothermic state) to the heating state (heat generation state) in the heat exchange condition.

  On the other hand, the power required to control the temperature of the solid-state laser crystal and the wavelength conversion element to 25 ° C. is 0.026 W, and the power required to control the temperature of the RGB laser base to 25 ° C. is 2.117 W. Was 2.143 W (Experimental Example 1). The power required to control the temperature of the solid-state laser crystal and the wavelength conversion element to 29 ° C. is 0.028 W, and the power required to control the temperature of the RGB laser base to 25 ° C. is 1.997 W. Was 2.025 W (Experimental Example 2). Furthermore, the power required to control the temperature of the solid-state laser crystal and the wavelength conversion element to 25 ° C. is 0.120 W, and the power required to control the temperature of the RGB laser base to 29 ° C. is 0.391 W. Was 0.511 W (Experimental Example 3).

  As described above, the temperature control power can be drastically reduced by controlling the temperature of the RGB laser base at a high temperature. However, it is known that when a semiconductor laser is driven at a high temperature, the lifetime until output degradation is shortened, and the upper limit of the driving temperature is limited from the guarantee of the lifetime quality. However, even if the driving temperature of the solid-state laser crystal and the wavelength conversion element is designed at about 60 ° C., no particular problem occurs, so the example is 29 ° C. However, by designing at a higher temperature and cooling the common substrate, The total power can be minimized.

  In addition, when the temperature of the solid laser crystal, the wavelength conversion element, and the RGB laser base is controlled to 29 ° C., an effect of reducing the temperature control power by 85% as compared with Experimental Example 1 can be obtained. An RGB laser light source having a conventional structure is a combination of individual devices, and the configuration size of each individual device is larger than that of each RGB laser unit of the embodiment of the invention, so that it is necessary for an actual conventional RGB laser light source. The temperature control power becomes a larger value.

  As described above, according to the RGB laser light source device according to the present invention in which the red laser light source, the green laser light source, and the blue laser light source are integrated and miniaturized, the component cost, the temperature control power, and the size weight are compared with the conventional one. The effect that it can improve significantly is acquired. Accordingly, the present invention is particularly effective when used for an RGB laser light source of a portable laser display device that is required to be small, light, low power consumption and low cost.

  The embodiment of the present invention has been described above. Of course, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention.

  For example, in the above embodiments, the optical axis adjustment mechanism is provided for all of the RGB laser light sources 2R, 2G, and 2B, so that the optical axis position can be adjusted for each color alone. By providing the optical axis adjusting mechanism in the light source, it is possible to adjust the position of the other two optical axes with reference to one optical axis.

It is a top view of the laser light source apparatus by embodiment of this invention. It is a side view of the laser light source apparatus by embodiment of this invention. 1 is an overall perspective view of a laser light source device according to an embodiment of the present invention. It is a disassembled perspective view of the laser light source apparatus by embodiment of this invention. It is a figure which shows the structure of the optical axis adjustment mechanism of the laser light source apparatus by embodiment of this invention, A is sectional drawing which looked at the structure of the bottom part of a laser plate from the upper surface side, B is a top view by the side of a mount surface. It is a figure explaining the optical axis adjustment method of the laser light source apparatus by embodiment of this invention. It is a figure which shows an example of the laser display apparatus with which the laser light source apparatus by embodiment of this invention is applied. It is a figure which shows the experimental result by one Example of this invention. It is a figure which shows the experimental result by the other Example of this invention. It is a schematic block diagram of the conventional laser light source device. It is a schematic block diagram of the other conventional laser light source apparatus. It is a schematic block diagram of the conventional laser display apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Laser light source device, 2R, 2G, 2B ... Laser light source, 3 ... Radiation substrate (common substrate), 4R, 4G, 4B ... Semiconductor laser, 5 ... Wavelength conversion element, 6 ... Solid laser crystal, 7R, 7G, 7B: spacer, 8R, 8G, 8B ... laser base, 17R, 17G, 17B ... guide groove, 18R, 18G, 18B ... reference pin, 19R, 19G, 19B ... eccentric driver insertion hole, 21R, 21G, 21B ... engagement 25, heat insulating plate, 26, base substrate, P1, first temperature control element (Peltier element), P2, second temperature control element (Peltier element)

Claims (8)

A red laser light source for generating red laser light;
A green laser light source for generating green laser light;
A blue laser light source for generating blue laser light;
A laser light source device comprising: a heat dissipation substrate on which the laser light sources of the respective colors are mounted in common. The laser light source device according to claim 1, further comprising a temperature control element for controlling the temperature of the heat dissipation substrate. The red laser light source and the blue laser light source are composed of a single semiconductor laser,
The green laser light source comprises a laser resonator including a wavelength conversion element, a solid-state laser crystal that oscillates its fundamental wave, and a semiconductor laser that excites the solid-state laser crystal,
The heat dissipation substrate has a first temperature control element for controlling the temperature of the heat dissipation substrate,
The laser light source device according to claim 1, wherein the green laser light source includes a second temperature control element for commonly controlling the temperature of the wavelength conversion element and the solid-state laser crystal. The laser light source device according to claim 3, wherein each of the first and second temperature control elements is a Peltier element. The first and second temperature control elements are each Peltier elements,
The first temperature control element controls the temperature of the heat dissipation substrate in an endothermic state,
The laser light source device according to claim 3, wherein the second temperature control element controls the temperature of the wavelength conversion element and the solid-state laser crystal in a heat generation state. The laser light source device according to claim 1, wherein the laser light sources of the respective colors are mounted on the heat dissipation substrate via dedicated heat conductive laser bases. The laser light source apparatus according to claim 6, wherein an optical element for controlling laser light generated by the laser light source is mounted on the laser base. A laser light source device for generating red, green and blue laser beams;
In a laser display device comprising a laser control system that modulates and scans the laser light of each color,
In the laser light source device, a red laser light source that generates red laser light, a green laser light source that generates green laser light, and a blue laser light source that generates blue laser light are mounted on a common heat dissipation substrate. A laser display device characterized by the above.

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