WO2017098554A1

WO2017098554A1 - Laser light source device

Info

Publication number: WO2017098554A1
Application number: PCT/JP2015/084282
Authority: WO
Inventors: 廣瀬　達朗
Original assignee: 三菱電機株式会社
Priority date: 2015-12-07
Filing date: 2015-12-07
Publication date: 2017-06-15

Abstract

A laser light source device 1 is provided with: a laser light emitting element 10 that has a light emitting section 14, a flange section 12, to which the light emitting section 14 is fixed, and an electric terminal section 11, which is electrically connected to the light emitting section 14, and which protrudes from the flange section 12; a base member 20 having a bottomed hole 21, in which the laser light emitting element 10 is disposed, and a hole 22, which is provided in a bottom surface 21a of the hole 21, and which the electric terminal section 11 passes through; and a solder sheet 30 having a hole 32, which has an outer shape equal to a shape formed by partially cutting out, in plan view, the outer shape of the flange section 12 by two parallel straight lines, and which is in communication with the hole 22, and which the electric terminal section 11 passes through, said solder sheet being sandwiched between the flange section 12 and the bottom surface 21a, and bonding the laser light emitting element 10 and the base member 20 to each other.

Description

Laser light source device

The present invention relates to a laser light source device using a laser light emitting element.

In recent years, laser light emitting devices have been used as light sources for large-sized high-intensity projectors for large halls or digital cinema, medium- and small-sized projectors mainly used for meetings or presentations with a small number of people, and projection televisions with a built-in projection optical system in the housing. Those that use are widely commercialized or proposed. Such projectors and projection televisions have advantages in that the color reproduction range is wide, instantaneous lighting is possible, power consumption is low, and the life is long compared to the case where a conventional lamp is used as a light source.

In general, since there is a limit to increasing the output of a single laser light-emitting element, in such projectors and projection televisions, the laser light source device can be efficiently combined by combining laser beams from a plurality of laser light-emitting elements. The light output is increased.

Further, it is known that the laser light emitting element is more efficient as the temperature of the light emitting portion is lower, and a high output and a long life can be obtained.

In Patent Document 1, a first holder that holds a laser light emitting element and a second holder that holds a lens that collects light emitted from the laser light emitting element are joined together with a heat conductive adhesive, thereby radiating heat from the laser light emitting element. A light source device with improved effects is described.

Patent Document 2 describes a technique for suppressing the spread and creeping of the solder while improving the heat conduction efficiency by joining the laser diode and the heat sink with solder.

JP2015-122142A JP 2008-124152 A

However, in the light source device described in Patent Document 1, since the thermal conductivity of the heat conductive adhesive is generally several W / K · m, there is a limit to improving the heat conduction efficiency, and light emission It is difficult to lower the temperature of the part. Therefore, it is difficult to obtain a laser light source device with high output, long life, and high reliability.

In addition, the technique described in Patent Document 2 has a problem that the structure is complicated because a member that suppresses the spread of solder is required.

The present invention has been made in view of the above, and an object of the present invention is to provide a laser light source device capable of realizing high output and high reliability with a simple structure.

In order to solve the above-described problems and achieve the object, a laser light source device according to the present invention includes a light emitting part, a flange part to which the light emitting part is fixed, and an electrical connection to the light emitting part and protruding from the flange part. A laser light emitting element having an electric terminal portion to be connected, a bottomed first hole in which the laser light emitting element is disposed, and a second hole provided in a bottom surface of the first hole and through which the electric terminal portion passes. The external shape of the base member and the flange portion when viewed in plan is the same shape as a shape partially cut by two straight lines, and communicates with the second hole and penetrates through the electrical terminal portion. And a solder sheet which is sandwiched between the flange portion and the bottom surface and which joins the laser light emitting element and the base member.

According to the present invention, there is an effect that it is possible to provide a laser light source device capable of realizing high output and high reliability with a simple structure.

Sectional drawing which shows the structure of the laser light source apparatus which concerns on Embodiment 1. FIG. 3 is an exploded perspective view for explaining the method for manufacturing the laser light source device according to the first embodiment. Sectional drawing for demonstrating the manufacturing method of the laser light source apparatus which concerns on Embodiment 1. FIG. The bottom view which shows the structure of the laser light emitting element of Embodiment 1. FIG. 3 is a side view showing the configuration of the laser light-emitting element of the first embodiment. Another side view showing the configuration of the laser light emitting element of the first embodiment The top view which shows the shape of the solder sheet of Embodiment 1 The side view which shows the shape of the solder sheet of Embodiment 1 In Embodiment 1, the bottom view of the laser light emitting element for explaining the wet spread of the solder In Embodiment 1, the side view of the laser light emitting element for demonstrating the wetting and spreading of the solder In Embodiment 1, another side view of the laser light emitting element for explaining the wetting and spreading of the solder The figure which shows the characteristic with respect to the combination of the material of a base member, the presence or absence of plating of a base member, and the presence or absence of the flux coating of a solder sheet in Embodiment 2.

Hereinafter, a laser light source device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing a configuration of a laser light source device according to the present embodiment, FIG. 2 is an exploded perspective view for explaining a method for manufacturing the laser light source device according to the present embodiment, and FIG. Sectional drawing for demonstrating the manufacturing method of the laser light source apparatus which concerns on embodiment, FIG. 4 is a bottom view which shows the structure of the laser light emitting element of this Embodiment, FIG. 5 is the laser light emitting element of this Embodiment FIG. 6 is another side view showing the configuration of the laser light emitting element of the present embodiment, FIG. 7 is a plan view showing the shape of the solder sheet of the present embodiment, and FIG. It is a side view which shows the shape of the solder sheet | seat of this Embodiment.

As shown in FIG. 1, a laser light source device 1 according to the present embodiment includes a laser light emitting element 10 that emits laser light and a hole 21 that is a bottomed first hole in which the laser light emitting element 10 is disposed. And a solder sheet 30 that is sandwiched between the base member 20 and the laser light emitting element 10 and joins the laser light emitting element 10 and the base member 20 to each other. The laser light source device 1 is used for a projector or a projector television.

As shown in FIGS. 1 to 6, the laser light emitting element 10 includes a light emitting unit 14 that emits laser light, an electric terminal unit 11 that is electrically connected to the light emitting unit 14, and a flange to which the light emitting unit 14 is fixed. Part 12.

The light emitting unit 14 has a cylindrical outer shape. The flange portion 12 has a disk shape. The outer diameter of the flange portion 12 is larger than the outer diameter of the light emitting portion 14, and the outer peripheral edge portion of the flange portion 12 protrudes from the light emitting portion 14 outward in the radial direction. The light emitting portion 14 is fixed to the upper end surface of the flange portion 12 coaxially with the flange portion 12.

The flange portion 12 has a circular outer shape in plan view, and has two notches 13 as concave portions on the outer periphery. Specifically, the two notches 13 are arranged at positions symmetrical in the circumferential direction with respect to the center of the flange portion 12. That is, the two cutouts 13 are spaced apart in the radial direction. The notch 13 has a corner E on the inside in the radial direction.

The electric terminal portion 11 has a pin shape and protrudes from the lower end surface of the flange portion 12. The number of electrical terminal portions 11 is generally two. Two notches 13 are arranged on an extension line of a line connecting the two electric terminal portions 11. When the electric terminal portion 11 is energized, the light emitting portion 14 oscillates and the laser light emitting element 10 emits laser light through the light emitting portion 14.

The base member 20 includes a plurality of holes 21 in which the plurality of laser light emitting elements 10 are respectively disposed. The base member 20 is a plate-shaped metal member. The hole 21 is a counterbore, and the depth thereof is smaller than the thickness of the base member 20. The hole 21 is circular when viewed from above. The diameter of the hole 21 is equal to or larger than the diameter of the flange portion 12 so that the flange portion 12 can be inserted.

The bottom surface 21a of the hole 21 is flat, and a hole 22 that is a second hole is provided at the center of the bottom surface 21a. The hole 22 is an oval long hole. The size of the hole 22 is smaller than the size of the flange portion 12, and the electric terminal portion 11 can penetrate the hole 22 without contacting the base member 20. Is set to That is, the electrical terminal portion 11 passes through the hole 22 in a state where the laser light emitting element 10 is disposed in the hole 21. As a result, wiring for energization from the lower end surface side of the base member 20 to the laser light emitting element 10 becomes possible.

In addition, the base member 20 includes a positioning hole 23. The positioning hole 23 is used when the laser light source device 1 is attached to a projection optical system of a projector or a projector television, and has a function of increasing optical efficiency. Therefore, disposing the laser light emitting element 10 on the base member 20 with high positional accuracy is also an important element for improving optical efficiency.

The exhaust heat of the laser light emitting element 10 is mainly made from the lower surface of the laser light emitting element 10 that is in contact with the base member 20, that is, the lower surface of the flange portion 12. The base member 20 enables thermal diffusion of the laser light emitting element 10, and furthermore, the base member 20 can be efficiently cooled by increasing the exhaust heat area through a cooler (not shown) attached to the base member 20. Therefore, reducing the contact thermal resistance between the laser light emitting element 10 and the base member 20 is an important element for increasing the cooling efficiency.

7 and 8, the outer shape of the solder sheet 30 is oval. The solder sheet 30 is a sheet-like solder and has a constant thickness. Further, the solder sheet 30 is provided with a hole 32 which is a third hole. Here, the hole 32 is an oval long hole.

Specifically, the outer shape of the solder sheet 30 is a part of a circle that forms the outer shape of the flange portion 12, and more precisely, a circle having the same size as the circle is arranged in parallel with two straight lines arranged symmetrically with respect to the center thereof. The shape is cut out. That is, the outer shape of the solder sheet 30 connects the

string portions

31a and 31b, which are first and second string portions spaced apart from each other in the radial direction, and one end of the string portion 31a and one end of the string portion 31b. An arc portion 31c that is a first arc portion, and an arc portion 31d that is a second arc portion that connects the other end of the chord portion 31a and the other end of the chord portion 31b. Here, the

arc portions

31c and 31d are spaced apart in the radial direction perpendicular to the arrangement direction of the

chord portions

31a and 31b.

The hole 32 has the same shape and the same size as the hole 22. The short direction of the hole 32 is parallel to the two parallel straight lines described above.

The solder sheet 30 is disposed on the bottom surface 21 a of the hole 21 with the hole 32 and the hole 22 communicating with each other. In a state where the solder sheet 30 is sandwiched between the laser light emitting element 10 and the base member 20, the

arc portions

31c and 31d coincide with a part of the outer shape of the flange portion 12, and 2 on the outer side in the radial direction of the chord portion 31a. One of the notches 13 is disposed, and the other of the two notches 13 is disposed on the outer side in the radial direction of the string portion 31b. That is, the string portion 31a faces one of the two notches 13 in the radial direction in plan view, and the string portion 31b faces the other of the two notches 13 in the radial direction in plan view. The radial direction is the radial direction of the flange portion 12.

Here, the dimensions of the configuration of the laser light source device 1 will be described. In the laser light emitting element 10 shown in FIG. 4, the outer diameter D = 9 mm, the outer diameter d of the electric terminal portion 11 = 0.6 mm, and the pitch P = 2.5 mm, which is the distance between the electric terminal portions 11. Further, in the solder sheet 30 shown in FIGS. 7 and 8, the longitudinal width W1 of the hole 32 = 3.8 mm, the lateral width W2 of the hole 32 = 1.3 mm, and the width W3 between the chord portions 31a and 31b. = 7 mm, thickness W4 = 0.1 mm.

Next, with reference to FIGS. 2 and 3, a method for manufacturing the laser light source device 1, specifically, a method for assembling the laser light emitting element 10 to the base member 20 will be described.

The solder placement jig 50 has the same shape as the hole 22 of the base member 20 in plan view and has a slightly smaller outer shape. Further, the solder arrangement jig 50 has a bottomed hole 50a into which the electric terminal portion 11 can be inserted at the tip. The shape of the hole 50 a is also the same shape as the hole 22.

When the solder sheet 30 is arranged on the base member 20, the solder arrangement jig 50 is passed through the hole 22, and the solder arrangement jig 50 having the tip protruding upward from the bottom surface 21a is disposed in the hole 32 of the solder sheet 30. While passing the jig 50, the solder sheet 30 is moved to the bottom surface 21a side, and the solder sheet 30 is arranged on the bottom surface 21a. After the solder sheet 30 is placed on the bottom surface 21 a, the solder placement jig 50 is pulled out from the hole 22. As described above, since the arrangement position of the solder sheet 30 is limited by the solder arrangement jig 50, it is uniquely determined with respect to the base member 20.

The laser arrangement jig 40 has a cylindrical portion 40a and two claw portions 41 provided at one end of the cylindrical portion 40a in the axial direction. The cylindrical portion 40a has the same shape as the hole 21 of the base member 20 in plan view and has a slightly smaller outer shape. The two claw portions 41 can be locked by the two notches 13 of the laser light emitting element 10, respectively, and the laser light emitting element 10 can be sandwiched and held at the two notches 13. is there.

When the laser light emitting element 10 is arranged on the base member 20, the two claw portions 41 are respectively locked by the two notches 13, and the laser light emitting element 10 is held by the laser arrangement jig 40, and the base member The laser arrangement jig 40 is inserted into the 20 holes 21 from above, and the laser light emitting element 10 is arranged on the solder sheet 30 arranged on the bottom surface 21a.

Note that the rotation direction of the laser arrangement jig 40 is limited by the outer shape of the base member 20 or the positioning shape such as the positioning hole 23, and the arrangement position of the laser light emitting element 10 is also unique with respect to the base member 20. It is determined.

Next, in a state where the solder sheet 30 is sandwiched between the laser light emitting element 10 and the base member 20, the solder sheet 30 is heated and melted. The solder sheet 30 is heated, for example, via the base member 20. When the temperature of the solder sheet 30 exceeds its melting point, the solder sheet 30 becomes liquid and wets and spreads on the surfaces of the laser light emitting element 10 and the base member 20. Thereafter, the solder sheet 30 is cooled to a temperature below the melting point, so that the solder sheet 30 returns to the solid state again, and the laser light emitting element 10 and the base member 20 are soldered.

The laser arrangement jig 40 remains attached to the laser light emitting element 10 even in the temperature rising process for melting the solder, and is removed from the laser light emitting element 10 and the base member 20 after being soldered through the cooling process. It is. Thereby, the arrangement position of the laser light emitting element 10 is fixed by the position accuracy determined by the laser arrangement jig 40 even after the solder bonding. The laser arrangement jig 40 may be applied with an external force from the top in order to prevent the laser light emitting element 10 from being lifted during the temperature rising process.

By the manufacturing method as described above, the laser light source device 1 after the laser arrangement jig 40 is removed is obtained as shown in FIG.

FIGS. 9 to 11 are diagrams for explaining solder wetting and spreading on the surface of the laser light emitting element 10 in a state where the laser light emitting element 10 is soldered to the base member 20. FIG. 10 is a side view of the laser light emitting element 10, and FIG. 11 is another side view of the laser light emitting element 10. 9 to 11, the same components as those shown in FIGS. 4 to 6 are denoted by the same reference numerals.

In FIGS. 9 to 11, the hatched area is an area where wetting and spreading of solder is prevented. Corresponding to the outer shape of the solder sheet 30, the solder is prevented from spreading around the notch 13, and corresponding to the hole 32 of the solder sheet 30, the solder is prevented from spreading around the electrical terminal portion 11. Is done.

In FIG. 9, the distance L representing the range of solder wetting and spreading in the radial direction connecting the two notches 13 is 7.7 mm, and the width W3 between the

chord portions

31a and 31b of the solder sheet 30 is 7 mm. Is also increased by wet spreading. However, the outer diameter D is 9 mm, and the dimension is set so that the wet spread area does not reach the corner E of the notch 13.

As described above, by using the solder sheet 30, the spread of the solder to the hatched area in FIGS. 9 to 11 is sufficiently limited.

As described above, according to the present embodiment, since the solder sheet 30 having the shape shown in FIG. 7 is used for joining the laser light emitting element 10 and the base member 20, the molten solder is the laser light emitting element 10. The range of wetting and spreading on the surface is limited.

That is, solder does not spread over a part of the side surface of the flange portion 12 including the notch 13 and a portion of the end surface of the flange portion 12 on the solder sheet 30 side including the notch 13. Therefore, when the laser light emitting element 10 is assembled using the side surface of the notch 13 by the laser arrangement jig 40, the laser arrangement jig 40 is unintentionally soldered to the laser light emission element 10 or soldered to the laser arrangement jig 40. Is prevented from becoming unusable due to adhesion, and simple and accurate positioning and assembly using the outer shape of the laser light emitting element 10 are possible.

Further, the solder does not spread even in the region around the electric terminal portion 11 in the end surface of the flange portion 12 on the solder sheet 30 side. Therefore, it is possible to prevent a solder bridge from being formed between the electric terminal portion 11 and the base member 20, and it is possible to maintain electric insulation, and reliability is improved.

In addition, according to the present embodiment, the contact thermal resistance between the laser light emitting element 10 and the base member 20 can be kept low by performing solder bonding between the laser light emitting element 10 and the base member 20. . Solder has a thermal conductivity of 10 times or more and a thickness of 1/2 or less compared to a heat-dissipating grease or heat conductive adhesive that is generally used, and therefore the contact thermal resistance is 1/20 or less. It is possible. Thus, by suppressing the contact thermal resistance to a low level, the cooling efficiency of the laser light emitting element 10 is increased and the temperature of the light emitting unit 14 is lowered. Therefore, the laser light source device 1 with higher output and longer life and higher reliability. Is obtained.

In addition, since the laser light emitting element 10 and the base member 20 are soldered, the fixing strength of the laser light emitting element 10 to the base member 20 increases. Therefore, it becomes difficult for the user to easily remove the laser light emitting element 10, and unauthorized use can be prevented in advance.

As described above, according to the present embodiment, it is possible to obtain the laser light source device 1 that can realize high output and high reliability with a simple structure.

In this embodiment, the hole 21 has a circular shape, the flange portion 12 has a disk shape, the

holes

22 and 32 have long holes, and the outer shape of the solder sheet 30 is obtained when the flange portion 12 is viewed in plan view. However, the present invention is not limited to these shapes. However, the shape is not limited to these shapes.

When the flange portion 12 has a shape other than the disk shape, the solder sheet 30 having an outer shape that is the same shape as a shape partially cut out by two straight lines that are parallel when the flange portion 12 is viewed in plan view. May be used. The size and shape of the hole 21 can be determined according to the size and shape of the flange portion 12. The size and shape of the hole 22 may be any as long as the electrical terminal portion 11 is not in contact with the base member 20. The size and shape of the positioning hole 23 are the same as in the case of the hole 22.

In the present embodiment, the notch 13 has a shape having a corner E, but is not limited thereto, and may be a concave shape with respect to the outer periphery of the flange portion 12.

Further, the dimensions of the configuration of the laser light source device 1 described above are an example. For example, in the solder sheet 30, the longitudinal width W1 of the hole 32 may be 3.8 mm or more, the lateral width W2 of the hole 32 may be 1.3 mm or more, and the width W3 between the

chord portions

31a and 31b may be 7 mm or less. it can. By doing so, it is possible to limit the spread of the solder onto the surface of the laser light emitting element 10 while securing the area of the solder joint. The width W3 is larger than the width W1.

In the present embodiment, the laser light source device 1 is used for a projector or a projector television, but is not limited to this, and can be used for other devices.

Embodiment 2. FIG.
In the present embodiment, a combination of the material of the base member 20 and the material of the solder sheet 30 will be described. Other configurations of the present embodiment are the same as those of the first embodiment.

FIG. 12 is a diagram showing characteristics with respect to a combination of the material of the base member 20, the presence or absence of plating of the base member 20, and the presence or absence of flux coating of the solder sheet 30.

The material of the base member 20 is required to have the structural strength of the laser light source device 1, the manufacturability of the base member 20, and the heat resistance in the temperature rising process at the time of soldering. For example, copper, aluminum, or iron is assumed. As shown in FIG. 12, the base material of the base member 20 is preferably copper or aluminum in consideration of the heat dissipation performance of the base member 20, and more preferably aluminum in consideration of cost. In FIG. 12, regarding “heat dissipation performance of the base member”, “◯” indicates that the heat dissipation performance is higher than “×”, and “cost” indicates that “○” is less expensive than “△”. Low, “Δ” indicates that the cost is lower than “x”.

The presence / absence of a surface oxide film on the base member 20 affects the solder wettability and the solder joint strength at the time of solder joint. Since a strong oxide film is formed on the surface of aluminum, solder bonding is generally difficult. Therefore, when aluminum is used for the base material of the base member 20, it is important to apply gold plating or nickel boron plating, which is a material in which a surface oxide film is difficult to be formed. It is desirable to do.

Also, the formation state of the surface oxide film changes depending on the temperature and humidity environment when the base member 20 is transported and stored. In general, the formation of a surface oxide film is accelerated in a high-temperature and high-humidity environment, but limiting the temperature-humidity environment during transportation and storage significantly affects cost and productivity.

Therefore, by using a flux at the time of soldering, the surface oxide film is destroyed and stable and good soldering can be obtained regardless of the temperature and humidity environment history of the base member 20. Since the flux to be used is coated on the surface of the solder sheet 30 in advance, the process of applying the liquid flux becomes unnecessary and the workability is improved. In FIG. 12, regarding “solder wettability and solder joint strength”, “◯” has higher solder wettability than “Δ” and higher solder joint strength, and “Δ” has higher solder wettability than “x”. It shows that solder joint strength is high.

From the above, in the present embodiment, the base member 20 is constituted by using nickel-plated aluminum as a base material, and the solder sheet 30 has a flux coating on the surface.

According to the present embodiment, it is possible to obtain a laser light source device 1 that is inexpensive and easily obtained with high fixing strength and has high cooling efficiency and high reliability.

The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

DESCRIPTION OF SYMBOLS 1 Laser light source device, 10 Laser light emitting element, 11 Electrical terminal part, 12 Flange part, 14 Light emitting part, 20 Base member, 21, 22, 32, 50a hole, 21a Bottom face, 23 Positioning hole, 30 Solder sheet, 31a, 31b String part, 31c, 31d arc part, 40 laser arrangement jig, 40a cylindrical part, 41 claw part, 50 solder arrangement jig.

Claims

A laser emitting element having a light emitting portion, a flange portion to which the light emitting portion is fixed, and an electric terminal portion that is electrically connected to the light emitting portion and protrudes from the flange portion;
A base member having a bottomed first hole in which the laser light emitting element is disposed and a second hole provided in a bottom surface of the first hole and through which the electric terminal portion passes;
A third outer shape having an outer shape that is the same as a shape partially cut out by two straight lines parallel to each other when the flange portion is viewed in plan, and that communicates with the second hole and through which the electric terminal portion passes. A solder sheet having a hole, sandwiched between the flange portion and the bottom surface, and joining the laser light emitting element and the base member;
A laser light source device comprising:
The first hole is circular;
The second and third holes are oblong holes;
The flange portion is disk-shaped,
The outer shape of the solder sheet has the same shape as a shape partially cut by the two straight lines arranged symmetrically with respect to the center of the circle when the flange portion is viewed in plan. ,
2. The laser light source device according to claim 1, wherein a short direction of the second and third holes is parallel to the two straight lines.
The flange portion has two concave portions on the outer periphery in plan view,
The two recesses are separated from each other in the radial direction of the flange portion,
The outer shape of the solder sheet is a first connecting the first and second chord portions spaced apart from each other in the radial direction, and one end of the first chord portion and one end of the second chord portion. And a second arc portion connecting the other end of the first chord portion and the other end of the second chord portion,
One of the two concave portions is opposed to the first chord portion in the radial direction in a plan view,
The laser light source device according to claim 2, wherein the other of the two concave portions is opposed to the second chord portion in the radial direction in a plan view.
The longitudinal width of the third hole is 3.8 mm or more,
The lateral width of the third hole is 1.3 mm or more,
The laser light source device according to claim 3, wherein a width between the first and second string portions is 7 mm or less.
The base member is composed of nickel-plated aluminum as a base material,
The laser light source device according to claim 2, wherein the solder sheet has a flux coating on a surface thereof.