阅读说明：本技术 光源装置 (Light source device ) 是由 永原靖治 于 2019-06-13 设计创作，主要内容包括：本公开提供一种能够期待斑点噪声的充分减轻的光源装置。本公开提供一种光源装置(1),该光源装置(1)具备：基板(12)；包含载置在基板(12)上的辅助座(40A、40B)以及载置在辅助座(40A、40B)上的半导体激光器元件(30)的激光光源(100A、100B),多个激光光源(100A、100B)各自独立地配置在基板(12)上,在相邻配置的出射相同波段的光的激光光源(100A、100B)中,各个激光光源(100A、100B)的半导体激光器元件(30)以及基板(12)之间的热阻不同。(The present disclosure provides a light source device that can expect sufficient reduction of speckle noise. The present disclosure provides a light source device (1), the light source device (1) comprising: a substrate (12); laser light sources (100A, 100B) including auxiliary seats (40A, 40B) mounted on a substrate (12) and semiconductor laser elements (30) mounted on the auxiliary seats (40A, 40B), wherein the plurality of laser light sources (100A, 100B) are independently arranged on the substrate (12), and in the laser light sources (100A, 100B) arranged adjacently and emitting light of the same wavelength band, the semiconductor laser elements (30) of the laser light sources (100A, 100B) and the substrate (12) have different thermal resistances.)

1. A light source device is provided with:

a substrate; and

a laser light source including an auxiliary mount mounted on the substrate and a semiconductor laser element mounted on the auxiliary mount,

the plurality of laser light sources are independently arranged on the substrate,

in the laser light sources which are arranged adjacent to each other and emit light of the same wavelength band, the thermal resistances between the semiconductor laser elements and the substrate of the respective laser light sources are different.

2. The light source device according to claim 1,

the light source device is provided with a plurality of modes in which two or more auxiliary seats having different thermal resistances are arranged adjacently.

3. The light source device according to claim 2,

two kinds of the auxiliary seats different in thermal resistance are alternately arranged.

4. The light source device according to any one of claims 1 to 3,

the auxiliary seats with different thermal resistances are made of different materials.

5. The light source device according to any one of claims 1 to 4,

in the auxiliary seats with different thermal resistances, the thicknesses of the auxiliary seats are different.

6. The light source device according to any one of claims 1 to 5,

the auxiliary seat having different thermal resistances has different areas in a plan view.

7. The light source device according to any one of claims 1 to 6,

the light source device includes a collimator lens corresponding to each of the laser light sources.

8. The light source device according to any one of claims 1 to 7,

the light source device includes a plurality of the laser light sources that emit blue light, a plurality of the laser light sources that emit green light, and a plurality of the laser light sources that emit red light.

Technical Field

The present invention relates to a light source device including a semiconductor laser.

Background

Light source devices including semiconductor lasers are used in various industrial fields. Among them, there is a light source device including a plurality of semiconductor laser elements that emit light in the same wavelength band. Among them, there is proposed a light source device including a semiconductor laser array in which a plurality of semiconductor laser elements are laterally arranged and integrally formed, and a heat sink in contact with a lower surface of the semiconductor laser array, in which a material of the heat sink is different between a central region and an end region in a lateral direction of the semiconductor laser array (for example, see patent document 1).

Prior art documents

Patent document

Patent document 1: WO2015/063973 gazette

Disclosure of Invention

Problems to be solved by the invention

In the light source device described in patent document 1, since the heat radiation efficiency is not uniform in the lateral direction of the semiconductor laser array, the wavelength width of the semiconductor laser element is widened, and speckle noise can be reduced. However, since the material of the heat sink is different only in the central region and the end region of the semiconductor laser array, the adjacent semiconductor laser elements are in contact with the heat sink of the same material except for the portion where the material is changed. Therefore, since the heat radiation efficiency of many adjacent semiconductor laser elements does not change so much and the wavelength of the emitted light does not change so much, it is not possible to sufficiently reduce speckle noise.

The present disclosure has been made in view of the above problems, and an object thereof is to provide a light source device which can expect sufficient reduction of speckle noise.

Means for solving the problems

In order to solve the above problem, a light source device according to an aspect of the present invention includes: a substrate; and a laser light source including an auxiliary mount mounted on the substrate and a semiconductor laser element mounted on the auxiliary mount, wherein the plurality of laser light sources are independently arranged on the substrate, and the semiconductor laser element and the substrate of each of the plurality of laser light sources emit light of the same wavelength band are different in thermal resistance between the laser light sources arranged adjacent to each other.

Effects of the invention

As described above, the present disclosure can provide a light source device that can expect sufficient reduction of speckle noise.

Drawings

Fig. 1 is a side view schematically showing a part of a light source device according to embodiment 1 of the present invention.

Fig. 2 is a side view schematically showing a part of a light source device according to embodiment 2 of the present invention.

Fig. 3 is a side view schematically showing a part of a light source device according to embodiment 3 of the present invention.

Fig. 4A is a side view schematically showing an example of an arrangement pattern of two types of laser light sources having different thermal resistances.

Fig. 4B is a side view schematically showing an example of the arrangement pattern of three types of laser light sources having different thermal resistances.

Fig. 4C is a side view schematically showing another example of the arrangement pattern of three laser light sources different in thermal resistance.

Fig. 5A is a plan view schematically showing an example of a light source device including a collimator lens corresponding to each laser light source.

Fig. 5B is a sectional view a-a in fig. 5A.

Fig. 5C is a sectional view B-B in fig. 5A.

Fig. 5D is a cross-sectional view C-C in fig. 5A.

Description of the reference numerals

1: light source device

10: package body

12: substrate

14: side wall

20: lens array

22: lens unit

24: connecting part

30: semiconductor laser element

40A to F: auxiliary seat

50: reflecting mirror

60: wire rod

70: relay member

82: main body part

84: translucent member

90: lead wire

100: laser light source

LA: light incident surface

LB: light exit surface

Detailed Description

Embodiments and examples for carrying out the present invention will be described below with reference to the drawings. The light source device described below is a device for embodying the technical idea of the present invention, and the present invention is not limited to the following as long as it is not specifically described.

In each drawing, members having the same function are sometimes denoted by the same reference numerals. In view of the ease of explanation and understanding of the points, the embodiments and examples may be divided for convenience, but partial replacement or combination of the structures shown in the different embodiments and examples may be possible. In the embodiments and examples described below, descriptions of common matters with the above are omitted, and only differences will be described. In particular, the same operations and effects based on the same structures are not mentioned in each embodiment and example in order. The sizes, positional relationships, and the like of the members shown in the drawings are exaggerated for clarity of description in some cases.

(light source device according to embodiment 1)

First, a light source device according to embodiment 1 of the present invention will be described with reference to fig. 1. Fig. 1 is a side view schematically showing a part of a light source device according to embodiment 1 of the present invention.

The light source device 1 according to the present embodiment includes: a substrate 12; and laser light sources 100 (specifically, 100A, 100B) including submount 40 (specifically, 40A, 40B) mounted on substrate 12 and semiconductor laser element 30 mounted on submount 40(40A, 40B), the plurality of laser light sources 100(100A, 100B) being arranged independently of each other on substrate 12. In particular, in the laser light sources 100A and 100B provided with the semiconductor laser elements 30 that emit light in the same wavelength band and arranged adjacent to each other, the thermal resistance between the semiconductor laser elements 30 and the substrate 12 of the laser light sources 100A and 100B is different.

Fig. 1 shows a region where two laser light sources 100A and 100B emitting light of the same wavelength band and having different thermal resistances between the semiconductor laser element 30 and the substrate 12 are arranged adjacent to each other in the light source device 1. In fig. 1, the semiconductor laser elements 30 emit laser beams of the same wavelength band in the direction perpendicular to the plane of the drawing.

Describing the structure of the laser light sources 100A and 100B in more detail, the semiconductor laser element 30 and the sub-mounts 40A and 40B are bonded to each other by the metal bonding layer 32, and the sub-mounts 40A and 40B and the substrate 12 are bonded to each other by the metal bonding layer 42. Examples of the material of the metal bonding layers 32 and 42 include gold tin (AuSn), gold (Au), silver (Ag), copper (Cu), solder, and a metal nanomaterial.

The thermal resistance between the semiconductor laser element 30 and the substrate 12 includes not only the thermal resistance of the sub-mounts 40A and 40B but also the thermal resistance of the metal bonding layer 32 and the metal bonding layer 42. However, it is difficult to make the thermal resistances of the metal bonding layers 32 and 42 greatly different between the laser light sources 100A and 100B, and it is effective to change the thermal resistances between the semiconductor laser element 30 and the substrate 12 by changing the thermal resistances of the sub-mounts 40A and 40B.

In order to change the thermal resistance of the submount 40A, 40B, in embodiment 1, the submount 40A of the laser light source 100A and the submount 40B of the laser light source 100B are formed of different materials. Specifically, ceramic is used as the material of the sub-mounts 40A and 40B, and in particular, aluminum nitride (AlN) is used as the material of the sub-mount 40A and silicon carbide (SiC) is used as the material of the sub-mount 40B.

Both silicon carbide (SiC) and aluminum nitride (AlN) have high thermal conductivity, and heat can be efficiently dissipated from the semiconductor laser element 30 toward the substrate 12. Among them, silicon carbide (SiC) has a higher thermal conductivity than aluminum nitride (AlN). Thus, the thermal resistance between the semiconductor laser element 30 and the substrate 12 in the laser light source 100A having the submount 40A is larger than that in the laser light source 100B having the submount 40B.

As described above, in the laser light sources 100A and 100B which are arranged adjacent to each other and emit light of the same wavelength band, the heat radiation state can be changed by making the thermal resistance between the semiconductor laser element 30 and the substrate 12 different from each other, and the junction temperature of the adjacent semiconductor laser elements 30 can be made different from each other. Therefore, the emission wavelengths of the adjacent laser light sources 100A and 100B can be made different, and speckle noise can be effectively suppressed.

As described above, in embodiment 1 of the present invention, the thermal resistance between the semiconductor laser element 30 and the substrate 12 can be changed by using the submount 40A or 40B having the same shape by changing the material of the submount in the adjacent laser light sources 100A and 100B that emit light in the same wavelength band. Therefore, the optical design and manufacturing of the light source device 1 are facilitated, and the thermal resistance can be efficiently changed at low manufacturing cost.

In the present embodiment, a semiconductor laser element 30 that emits light having an arbitrary wavelength from the ultraviolet region to the infrared region can be used. When at least two laser light sources emitting light of the same wavelength band and having different thermal resistances are arranged adjacent to each other, the light source device may emit light of one wavelength band or may emit light of a plurality of wavelength bands.

The material for forming the sub-mount 40 is not limited to the above-mentioned material, and alumina (Al) may be used₂O₃) Silicon nitride (Si)₃N₄) And other materials such as ceramic materials, silicon, and resin.

In the present embodiment, aluminum nitride (AlN) is used as a material of the substrate 12. However, the present invention is not limited thereto, and silicon carbide (SiC) and aluminum oxide (Al) may be used₂O₃) Silicon nitride (Si)₃N₄) And other ceramic materials, resin materials, single crystals of silicon and the like, metal materials provided with an insulating layer, and the like.

(light source device according to embodiment 2)

Next, a light source device according to embodiment 2 of the present invention will be described with reference to fig. 2. Fig. 2 is a side view schematically showing a part of a light source device according to embodiment 2 of the present invention.

Fig. 2 shows regions of the light source device 1 in which laser light sources 100C and 100D emitting light of the same wavelength band and having different thermal resistances between the semiconductor laser element 30 and the substrate 12 are arranged adjacent to each other. In fig. 2, the semiconductor laser elements 30 emit laser beams of the same wavelength band in the direction perpendicular to the plane of the drawing.

Embodiment 2 is different from embodiment 1 in that, in laser light sources 100C and 100D arranged adjacent to each other and emitting light of the same wavelength band, submount 40C and 40D having different thicknesses (height dimensions) are used to change the thermal resistance between the semiconductor laser element 30 and the substrate 12. The auxiliary seats 40C and 40D are formed of the same material.

More specifically, in the present embodiment, the auxiliary seat 40C having the thickness T1 and the auxiliary seat 40D having the thickness T2 are used. The thickness T1 is thicker than the thickness T2, and thus the thermal resistance between the semiconductor laser element 30 and the substrate 12 in the laser light source 100C having the submount 40C is larger than that in the laser light source 100D having the submount 40D.

In the present embodiment, by adjusting the thicknesses of the auxiliary seats 40C and 40D, the difference in thermal resistance between the semiconductor laser element 30 and the substrate 12 can be easily and reliably adjusted in the adjacent laser light sources 100C and 100D that emit light in the same wavelength band.

Other points are basically the same as those in embodiment 1, and therefore further description thereof is omitted.

(light source device according to embodiment 3)

Next, a light source device according to embodiment 3 of the present invention will be described with reference to fig. 3. Fig. 3 is a side view schematically showing a part of a light source device according to embodiment 3 of the present invention.

Fig. 3 shows regions of the light source device 1 in which laser light sources 100E and 100F emitting light of the same wavelength band and having different thermal resistances between the semiconductor laser element 30 and the substrate 12 are arranged adjacent to each other. In fig. 3, the semiconductor laser elements 30 emit laser beams of the same wavelength band in the direction perpendicular to the plane of the drawing.

Embodiment 3 is different from embodiments 1 and 2 described above in that, in laser light sources 100E and 100F arranged adjacent to each other and emitting light of the same wavelength band, auxiliary seats 40E and 40F having different areas in plan view are used to change the thermal resistance between the semiconductor laser element 30 and the substrate 12. In addition, the auxiliary seats 40E and 40F are formed of the same material.

More specifically, in the present embodiment, the auxiliary seat 40E having the width W1 and the auxiliary seat 40F having the width W2 are used. Width dimension W1 is less than width dimension W2. The dimension in the direction perpendicular to the width direction is the same in the auxiliary seats 40E and 40F, and the heat radiation area of the auxiliary seat 40E is smaller than the heat radiation area of the auxiliary seat 40F. Thus, the thermal resistance between the semiconductor laser element 30 and the substrate 12 in the laser light source 100E having the submount 40E is larger than that in the laser light source 100D having the submount 40F.

In the present embodiment, by adjusting the area of the sub-mounts 40E and 40F in a plan view, the difference in thermal resistance between the semiconductor laser element 30 and the substrate 12 can be easily and reliably adjusted in the adjacent laser light sources 100E and 100F that emit light in the same wavelength band.

Other points are basically the same as those of the above-described embodiments 1 and 2, and therefore, further description thereof is omitted.

As described above, according to the light source device 1 of the above embodiment, in the laser light sources 100 of the same wavelength which are adjacently arranged, the thermal resistance between the semiconductor laser element 30 and the substrate 12 is made different, whereby the heat radiation state can be changed without adding a special member, and the junction temperature of the semiconductor laser element 30 can be made different. This makes it possible to make the emission wavelengths of the adjacent laser light sources 100 different from each other, and effectively suppress speckle noise. Therefore, the light source device 1 expected to sufficiently reduce speckle noise can be provided.

It can be said that the difference in the thermal resistance between the semiconductor laser element 30 and the substrate 12 is preferably 0.5 ℃/W or more. This can reliably suppress the occurrence of speckle noise.

In addition, when the wavelengths of the light emitted from the laser light sources 100 arranged adjacent to each other are different, since the necessity of considering the generation of speckle noise is low, the submount 40 having the same thermal resistance between the semiconductor laser element 30 and the substrate 12 can be used.

In fig. 1 to 3, two types of submount 40 having different thermal resistances are used, but when laser light sources for emitting light of the same wavelength are disposed more adjacent to each other, any number of submount 40 having different thermal resistances can be used. In this case, it is also possible to use a plurality of types of sub-mounts 40 having different thermal resistances in combination with the above-described embodiments 1 to 3. Further, in addition to the sub-mount 40, the thermal resistance in the metal bonding layers 32, 42 can be made different.

(arrangement mode of laser light sources having different thermal resistances)

Next, the arrangement pattern of the plurality of types of laser light sources having different thermal resistances between the semiconductor laser element and the substrate will be described with reference to fig. 4A to 4C. Fig. 4A is a side view schematically showing an example of an arrangement pattern of two types of laser light sources having different thermal resistances. Fig. 4B is a side view schematically showing an example of the arrangement pattern of three types of laser light sources having different thermal resistances. Fig. 4C is a side view schematically showing another example of the arrangement pattern of three laser light sources different in thermal resistance. In any arrangement mode, 12 laser light sources emitting light of the same wavelength band are adjacently arranged on the substrate 12. In fig. 4A to 4C, the semiconductor laser element and the sub-mount are not separately illustrated, but the laser light source is schematically illustrated by a rectangle.

In the example shown in fig. 4A, two types of laser light sources 100P and 100Q having different thermal resistances between the semiconductor laser element and the substrate 12, that is, having different thermal resistances of the submount, are alternately arranged. With such a configuration, speckle noise can be efficiently suppressed with fewer types of auxiliary seats.

In the example shown in fig. 4B, three types of laser light sources 100P, 100Q, and 100R having different thermal resistances are used, and the arrangement pattern of the laser light sources 100P, 100Q, and 100R in this order is repeated from the left side to the right side in the drawing.

In the example shown in fig. 4C, three types of laser light sources 100P, 100Q, and 100R having different thermal resistances are used, and the arrangement pattern of the laser light sources 100P, 100Q, and 100R in this order and the arrangement pattern of the laser light sources 100Q, 100P, and 100R in this order are alternately repeated from the left side to the right side in the drawing.

In either case, the semiconductor laser device has an arrangement pattern in which two or more types of laser light sources having different thermal resistances between the semiconductor laser element and the substrate, that is, having different thermal resistances of the sub-mount are arranged adjacent to each other, and by repeating this arrangement pattern, speckle noise can be efficiently suppressed with a small number of types of sub-mounts.

Further, by repeating the arrangement pattern of two or more laser light sources having different thermal resistances, it is possible to effectively suppress the color distribution from being unbalanced due to the emission wavelengths of the two or more light sources.

The method of repeating the arrangement pattern in which two or more kinds of laser light sources having different thermal resistances are arranged adjacent to each other is not limited to the above example, and any other arrangement pattern can be adopted.

(light source device with collimating lens)

Next, an example of a light source device including a collimator lens corresponding to each laser light source according to the above-described embodiment will be described with reference to fig. 5A to 5D. Fig. 5A is a plan view schematically showing an example of a light source device including a collimator lens corresponding to each laser light source. Fig. 5B is a sectional view a-a in fig. 5A, fig. 5C is a sectional view B-B in fig. 5A, and fig. 5D is a sectional view C-C in fig. 5A.

As shown in fig. 5A to 5D, the light source device 1 includes a package 10 including a substrate 12 and a sidewall 14, and a lens array 20 including a plurality of lens portions 22 in a matrix. The lens array 20 is an integrally molded transparent glass member in which a plurality of lens portions 22 are connected by a connecting portion 24. A main body 82 and a translucent member 84 for sealing the inside of the package 10 are disposed below the lens array 20.

A plurality of laser light sources 100 including the semiconductor laser element 30 and the submount 40, and a reflector 50 corresponding to each laser light source 100 are mounted on the substrate 12. Power is supplied to each laser light source 100 from the outside of the package 10 via the lead 90, the wiring 60, and the relay member 70.

Fig. 5A is a perspective view showing a laser light source 100 including a semiconductor laser element 30 and an auxiliary mount 40 arranged below the leftmost lens portion 22 of the lens array 20 for easy understanding.

The light source device 1 includes a plurality of laser light sources 100 that emit blue light, a plurality of laser light sources 100 that emit green light, and a plurality of laser light sources 100 that emit red light. In the laser light sources 100 that emit light in the same wavelength band of blue light, green light, or red light, which are adjacently arranged, the thermal resistance between the semiconductor laser element 30 and the substrate 12 of each laser light source 100 is different. Any of the above embodiments can be adopted in order to make the thermal resistance different.

The semiconductor laser element 30 of each laser light source 100 emits laser light in the horizontal direction and is reflected by the corresponding mirror 50 in the substantially vertical direction. The reflected light passes through the light-transmitting member 84, reaches the light incident surface LA of the lens array 20, and passes through each lens portion 22, whereby parallel light is emitted from the light emitting surface LB of the lens array 20. The parallel light beams emitted from the lens portions 22 of the lens array 20 are condensed by, for example, a condenser lens, and the light beams of the respective wavelengths are combined. This enables white light with little speckle noise to be emitted. In the present embodiment, since the laser light sources 100 are independently arranged, the collimator lenses (lens portions) 22 corresponding to the laser light sources 100 can be easily arranged.

In the above, the light source device 1 in which the light from the laser light sources 100 is reflected in the substantially vertical direction by the reflecting mirror 50 is shown, but the present invention is not limited thereto, and the light emitted in the horizontal direction from each laser light source 100 may be emitted in the horizontal direction directly to the outside from the light source device without passing through the reflecting mirror. In the above, the case of the white light source is shown, but the white light source is not limited to this, and may be a light source device that emits light of a single wavelength in an arbitrary wavelength region or a light source device that emits light of arbitrary multiple wavelength regions.

While the embodiments and embodiments of the present invention have been described, the disclosure may be modified in details of the structure, and combinations of elements and sequences in the embodiments and embodiments may be implemented without departing from the scope and spirit of the claimed invention.