JP6922236B2 - Laser light emitting device, engine spark plug system - Google Patents

Description

The present disclosure relates to a laser emitting device and an engine spark plug system.

Some laser light emitting devices collect and output high-power laser light from a laser light source unit with a condenser lens, and the laser light is used to ignite an internal combustion engine (engine ignition plug system). It is considered (see, for example, Patent Document 1).

In such a laser light emitting device, the laser light source unit generates heat when outputting a high-intensity laser beam and is provided in a high temperature environment due to the heat from the internal combustion engine. If this is done, the life may be shortened or the output may be reduced. Therefore, in the above-mentioned conventional laser light emitting device, by keeping the laser light source unit at a low temperature by using a cooling device, it is possible to prevent the life from being shortened and the output from being lowered.

By the way, in the above-mentioned conventional laser light emitting device, since the high-intensity laser light output from the laser light source unit is condensed by the condensing lens, the condensing lens absorbs a part of the laser light as heat energy. It causes the temperature of the condenser lens to rise. Then, in the laser light emitting device, since the optical performance of the condensing lens is generally temperature-dependent, it may not be possible to condense the laser light at a predetermined position, and it may not be possible to appropriately output the target amount of light.

The present disclosure has been made in view of the above circumstances, and provides a laser emitting device capable of suppressing a temperature rise of a condensing lens even if a high-intensity laser beam is condensing with a condensing lens. The purpose.

Laser light emitting device of the present disclosure, holds a laser light source unit for emitting a laser beam, a condenser lens for condensing the laser beam emitted from the laser light source section to a predetermined position, the front Symbol condensing lens-holding A member and a cooling device for cooling the laser light source unit are provided, and the holding member has a higher thermal conductivity than the condenser lens, and the portion in surface contact with the condenser lens and the cooling device It is characterized by having a portion that comes into surface contact.

In the laser light emitting device according to the present disclosure, even if a high-intensity laser beam is focused by a condenser lens, the temperature rise of the condenser lens can be suppressed.

The engine spark plug system 40 of the first embodiment according to the embodiment of the engine spark plug system of the present disclosure in which the laser light emitting device 10 of the first embodiment according to one embodiment of the laser light emitting device of the present disclosure is used for ignition of an internal combustion engine. It is explanatory drawing which shows the structure. It is explanatory drawing which shows the structure of the laser light emitting device 10 schematicly. It is sectional drawing which shows the cross section obtained along the line I-I of FIG. It is explanatory drawing for demonstrating how each electric wire 12 and each electrode piece 19 are attached to a heat diffusion plate 15. It is explanatory drawing which shows typically the structure of the laser light emitting device 10A of another example which concerns on one Embodiment of the laser light emitting device of this disclosure. It is explanatory drawing which shows typically the structure of the laser light emitting device 10B of another example which concerns on one Embodiment of the laser light emitting device of this disclosure. It is explanatory drawing which shows typically the structure of the laser light emitting device 10C of another example which concerns on one Embodiment of the laser light emitting device of this disclosure. It is explanatory drawing which shows typically the structure of the laser light emitting device 10D of another example which concerns on one Embodiment of the laser light emitting device of this disclosure. It is explanatory drawing which shows schematic structure of the laser light emitting device 10E of Example 2 which concerns on one Embodiment of the laser light emitting device of this disclosure. FIG. 5 is a flowchart showing a temperature control process (temperature control method) executed by the temperature control device 62 of the laser light emitting device 10E. It is explanatory drawing which shows typically the structure of the laser light emitting device 10F of another example which concerns on one Embodiment of the laser light emitting device of this disclosure. It is explanatory drawing which shows schematic structure of the laser light emitting device 10G of Example 3 which concerns on one Embodiment of the laser light emitting device of this disclosure. FIG. 5 is a flowchart showing a temperature control process (temperature control method) executed by the temperature control device 62G of the laser light emitting device 10G. It is explanatory drawing which shows schematic structure of the laser light emitting device 10H of Example 4 which concerns on one Embodiment of the laser light emitting device of this disclosure. FIG. 5 is a flowchart showing a temperature control process (temperature control method) executed by the temperature control device 62H of the laser light emitting device 10H. It is explanatory drawing which shows schematic structure of the laser light emitting device 10I of Example 5 which concerns on one Embodiment of the laser light emitting device of this disclosure. FIG. 5 is a flowchart showing a temperature control process (temperature control method) executed by the temperature control device 62I of the laser light emitting device 10I. It is explanatory drawing which shows schematic structure of the laser light emitting device 10J of Example 6 which concerns on one Embodiment of the laser light emitting device of this disclosure. FIG. 5 is a flowchart showing a temperature control process (temperature control method) executed by the temperature control device 62J of the laser light emitting device 10J.

Hereinafter, each embodiment of the laser light emitting device according to the present disclosure and the engine ignition plug system including the laser light emitting device will be described with reference to the drawings.

The laser light emitting device 10 of the first embodiment as an example of the laser light emitting device according to the present disclosure will be described with reference to FIGS. 1 to 4. At the same time, the engine spark plug system 40 of the first embodiment as an example of the engine spark plug system including the laser light emitting device 10 as an example thereof will be described. In FIG. 1, the laser light emitting device 10 is omitted in order to facilitate understanding of the configuration of the engine spark plug system 40. Further, in FIG. 2, the exterior member 28 is omitted in order to facilitate understanding of the configuration of the laser light emitting device 10. Further, FIGS. 2 to 4 schematically show the configuration of each part in order to facilitate understanding of the configuration of the laser light emitting device 10.

As shown in FIG. 1, the laser light emitting device 10 of the first embodiment as the laser light emitting device according to the present disclosure constitutes an engine spark plug system 40 and ignites an engine 41 as an example of an internal combustion engine. Used for. The engine 41 is configured such that an intake valve 43 is provided in an intake pipe 42, an exhaust valve 45 is provided in an exhaust pipe 44, and a combustion chamber 46 is partitioned by a piston 47 or the like. The intake valve 43 and the exhaust valve 45 are moved forward and backward by the cams 48 connected to each of the intake valve 43 and the exhaust valve 45 to appropriately open and close the intake pipe 42 or the exhaust pipe 44. The combustion chamber 46 is cooled by the cooling water 51 supplied to the cooling water channel 49 provided in the peripheral wall portion thereof. A spark plug 52 is provided in the combustion chamber 46.

The spark plug 52 ignites using a laser beam emitted from the laser light emitting device 10, and is an ignition plug for an internal combustion engine having excellent ignition efficiency. In the spark plug 52, the laser beam from the laser light emitting device 10 is applied to a laser resonator including a Q-switch type laser medium to oscillate a giant pulse. Further, in the spark plug 52, the pulsed light is condensed in the combustion chamber 46 of the engine 41 by using an optical element such as a condenser lens to generate an air breakdown, so that the air-fuel mixture in the combustion chamber 46 is ignited. I do. Therefore, the other end of the optical fiber 13 (the emission end surface 13b thereof) of the laser light emitting device 10, which will be described later, is connected to the spark plug 52.

The laser light emitting device 10 is fixedly provided in the vicinity of the engine 41, and in the first embodiment, a heat sink 32 as a cooling device 30 described later is attached to an engine outer shell portion 53 forming an outer diameter of the engine 41 via a mounting support portion. It is fixed and provided. The mounting support portion may be formed integrally with the engine outer shell portion 53, may be formed separately from the engine outer shell portion 53, or may be formed integrally with the heat sink 32.

As shown in FIGS. 2 and 3, the laser light emitting device 10 is configured by connecting each electric wire 12 as a conductor and an optical fiber 13 to a housing 11. In the laser light emitting device 10, when electric power is supplied through each electric wire 12 (conductor), a high-intensity laser beam is output through the optical fiber 13. The housing 11 includes a lens holding member 14 having a box shape with one end open, and a heat diffusing plate 15 having a plate shape as a whole, and the heat diffusing plate is provided so as to close the open end of the lens holding member 14. 15 is attached and configured.

As shown in FIG. 3, the lens holding member 14 has a hollow rectangular parallelepiped shape as a whole, one end (14a) thereof is opened, and the open end surface 14a is positioned on the same plane. The lens holding member 14 is a holding member that holds the condensing lens 23, which will be described later, and has a higher thermal conductivity than the condensing lens 23 that holds the condensing lens 23. The lens holding member 14 is formed of, for example, a metal material such as iron, copper, or stainless steel, and is formed of aluminum as an example in Example 1. The lens holding member 14 is provided with a lens holding hole 16 in the back wall 14b opposite to the open side, and two electric wire insertion holes 14d (only one is shown in FIG. 3) in the lower wall 14c orthogonal to the back wall 14b. prepare. Both electric wire insertion holes 14d are places through which the electric wires 12 are passed, and the electric wires 12 are passed through while maintaining airtightness.

The lens holding hole 16 is a place for holding the condenser lens 23, which will be described later, in order to prevent the large inner diameter portion 16a into which the condenser lens 23 can be fitted and the condenser lens 23 fitted therein from falling off. It has a small inner diameter portion 16b having an inner diameter smaller than that of the large inner diameter portion 16a. In the large inner diameter portion 16a, the inner side surface 16c that surrounds the central axis of the lens holding hole 16 and defines the inner circumference is made a surface parallel to the central axis, so that the outer surface of the condensing lens 23 fitted therein will be described later. Allows surface contact with 23c. Further, the large inner diameter portion 16a (inner side surface 16c thereof) has a dimension seen in the direction in which the central axis of the lens holding hole 16 extends from the dimension of the outer surface 23c of the condenser lens 23 in the direction in which the central axis extends. Also increase. Therefore, the inner side surface 16c (the area thereof) is larger than the outer surface 23c (the area thereof) which is made to be able to make surface contact. In the lens holding hole 16, the back end surface 16d is formed by the step between the large inner diameter portion 16a and the small inner diameter portion 16b, and the back end surface 16d is made a plane orthogonal to the central axis of the lens holding hole 16. The heat diffusion plate 15 is attached to the open end (open end surface 14a) of the lens holding member 14.

The heat diffusion plate 15 is a base member on which the laser array chip 21 is provided so as to position the laser array chip 21 in the housing 11 described later. The heat diffusion plate 15 is a heat diffusion member having a function of efficiently diffusing the heat generated by the provided laser array chip 21, and has a size that secures a sufficient endothermic area for cooling the laser array chip 21. .. In the first embodiment, the heat diffusion plate 15 has a flat plate shape having a size capable of closing the open end of the lens holding member 14 while bringing the peripheral edge portion into surface contact with the open end surface 14a of the lens holding member 14. The heat diffusion plate 15 has a thermal conductivity of 14 or more (same or higher) than the lens holding member 14 as a holding member, and a material having a high thermal conductivity (thermal conductivity) such as a metal material is used. In Example 1, it is formed using copper.

As shown in FIGS. 1, 3, and 4, the heat diffusion plate 15 is provided with a mount portion 17 for mounting (arranging) the laser array chip 21, which will be described later. In the first embodiment, the mount portion 17 is configured by providing an insulating layer on the heat diffusion plate 15 and appropriately providing a plurality of conductive layers on the insulating layer so as not to contact each other. The insulating layer is formed using, for example, aluminum nitride (AlN (aluminum nitride)), and the conductive layer is formed using, for example, copper (Cu). In the mount portion 17, a circuit for the laser array chip 21 is formed by a plurality of conductive layers insulated from each other by an insulating layer on the heat diffusion plate 15. Further, the mount portion 17 is provided with a positioning portion for positioning the laser array chip 21. The positioning portion may be formed of protrusions or recesses as long as it is positioned in contact with a predetermined portion of the laser array chip 21.

As shown in FIGS. 3 and 4, the heat diffusion plate 15 is provided with an insulating member 18. The insulating member 18 constitutes a portion to which each electric wire 12 and each electrode piece 19 described later are attached while cutting off the conduction of electricity to the heat diffusion plate 15. In the first embodiment, the insulating member 18 is formed of at least a material that is more easily elastically deformed than the mount portion 17 (a material having a low elastic modulus), and more preferably, the electrode pieces 19 when the electrode pieces 19 are attached. It shall absorb the amount of deformation due to the stress from. Absorption of this amount of deformation is possible by setting the dimensions and shape while considering the elastic modulus of the material. In Example 1, the insulating member 18 is formed by using a resin material having an insulating property, and is formed by using POM (polyoxymethylene) as an example. The insulating member 18 has a rectangular parallelepiped shape, and constitutes a portion where each electrode piece 19 and each electric wire 12 are electrically connected and attached to the heat diffusion plate 15 as described later. A fixing screw hole 18a (see FIG. 4) for tightening and fixing the screw 26, which will be described later, is formed in the insulating member 18, and each electrode piece 19 and each electric wire 12 can be attached.

The electric wires 12 and the electrode pieces 19 are electrically connected to each other and attached to the insulating member 18 in order to supply electric power to the laser array chip 21 provided on the mount portion 17. As will be described later, each electric wire 12 is connected to an external power supply device, and each electrode piece 19 is connected to the laser array chip 21 via a mount portion 17. In the first embodiment, since the laser array chip 21 assumes the input of a high current of 100 (A) or more as described later, it is assumed that each electric wire 12 and each electrode piece 19 have a sufficient cross-sectional area. .. Along with this, a large force acts on each electric wire 12 for fixing, so as an example, a ring-shaped connection terminal 12a is provided at the tip. Further, each electrode piece 19 has a long plate shape made of a conductive material, and a mounting piece portion 19b having a mounting hole 19a (see FIG. 4) is provided at the base end. As will be described later, in each of the electrode pieces 19, the mounting piece 19b is attached to the insulating member 18, and the tip 19c on the opposite side of the mounting piece 19b is pressed against the mounting 17.

The laser array chip 21 provided on the mount portion 17 is configured by arranging a plurality of surface emitting lasers as an example. In the first embodiment, the laser array chip 21 is configured by appropriately arranging a plurality of vertical cavity surface emitting lasers (VCSEL (Vertical Cavity Surface Emitting Laser)). Each VCSEL is composed of a cylindrical active region and a reflecting mirror sandwiching a thin film active layer, and emits laser light from a resonator formed in a direction orthogonal to the main surface. Each VCSEL is formed by coating a VCSEL array substrate with a photomask and following the patterning of the photomask. With such a configuration, the laser array chip 21 requires an input of a high current (a pulse current of 100 (A) or more in this example) in order to appropriately emit laser light from each VCSEL. As a result, the laser array chip 21 can output high intensity (light intensity) laser light even with a small size.

When a predetermined power is supplied, the laser array chip 21 emits laser light from each VCSEL from the emission surface 21a. The laser array chip 21 is positioned by pressing a predetermined portion against the positioning portion of the mount portion 17, and is arranged on the mount portion 17. Then, the laser array chip 21 is electrically connected to the circuit formed in the mount portion 17 by wire bonding, flip chip bonding, or the like, and mounted on the mount portion 17. As a result, the laser array chip 21 is provided by being accurately positioned on the heat diffusion plate 15 (mount portion 17 thereof) as a base member, and electric power can be supplied via both electric wires 12 and each electrode piece 19. The laser array chip 21 may be provided on the mount portion 17 by positioning the laser array chip 21 while observing the alignment mark or the like with a microscope instead of pressing the laser array chip 21 against the positioning portion of the mount portion 17. A collimator lens 22 is provided in the emission direction of the laser beam from the laser array chip 21 (see FIG. 3).

As shown in FIG. 3, the collimator lens 22 uses a laser beam emitted as a divergent luminous flux from the laser array chip 21 (its emission surface 21a) as a parallel luminous flux (actually, a loose divergent luminous flux). In the first embodiment, the collimator lens 22 is configured by providing a plurality of microlenses corresponding to each VCSEL in the laser array chip 21 to form a lens array. The collimator lens 22 may be integrally configured with the laser array chip 21, or may be provided on the mount portion 17 (heat diffusing plate 15) or the lens holding member 14 as a configuration separate from the laser array chip 21. The collimator lens 22 may have other configurations as long as the laser beam emitted from the laser array chip 21 is a parallel luminous flux, and is not limited to the configuration of the first embodiment. A condenser lens 23 is provided in the traveling direction of the laser beam as a parallel luminous flux passing through the collimator lens 22.

The condensing lens 23 is formed of a glass material, and condenses the laser beam as a parallel light flux passing through the collimator lens 22 and causes it to be incident on the incident end surface 13a of the optical fiber 13. Therefore, in the first embodiment, the condensing lens 23 functions as a condensing lens that condenses the laser light emitted from the laser array chip 21 onto the incident end surface 13a (optical fiber 13) at a predetermined position. In the first embodiment, the condenser lens 23 has a plano-convex shape in which the collimator lens 22 side is a convex surface 23a and the opposite side is a flat surface 23b, and the convex surface 23a and the flat surface 23b are connected to each other while surrounding the optical axis. The side surface 23c is a plane parallel to the optical axis. In the condenser lens 23, the antireflection treatment film 23d is provided on the outer surface composed of the convex surface 23a, the flat surface 23b, and the outer surface 23c. The antireflection treated film 23d prevents a decrease in the amount of light due to Fresnel reflection, and is formed by applying AR coating in Example 1.

In the first embodiment, the condensing lens 23 is positioned and provided in the lens holding hole 16 of the back wall 14b of the lens holding member 14. Specifically, the condensing lens 23 is inserted into the large inner diameter portion 16a of the lens holding hole 16 from the flat surface 23b side, and the flat surface of the condensing lens 23 is brought into surface contact with the inner side surface 16c of the large inner diameter portion 16a. The 23b is brought into surface contact with the back end surface 16d of the lens holding hole 16. As a result, the position of the condenser lens 23 in the lens holding hole 16 as viewed in the direction in which the optical axis (central axis) extends is determined in a state where the optical axis is aligned with the central axis of the lens holding hole 16. .. Then, the presser ring 24 is inserted into the lens holding hole 16 (large inner diameter portion 16a) from behind the condenser lens 23 (collimator lens 22 side), and the presser ring 24 is fixed while being pressed against the convex surface 23a of the condenser lens 23. By doing so, the condenser lens 23 is fixed and held in the lens holding hole 16. As a result, the condenser lens 23 is accurately positioned and provided on the lens holding member 14 as the holding member. An optical fiber 13 (incident end surface 13a thereof) is provided in the traveling direction of the laser beam as the focused luminous flux passing through the condenser lens 23. The presser ring 24 and the small inner diameter portion 16b (back end surface 16d) have a diameter dimension that allows contact with the outer position of the effective diameter (effective luminous flux diameter) of the condenser lens 23.

As shown in FIG. 3, the optical fiber 13 has an incident end surface 13a at one end and an emission end surface 13b (see FIG. 1) at the other end, and emits laser light incident on the incident end surface 13a (one end) at the emission end surface 13b (others). Exit from the edge). The other end (emission end surface 13b) is connected to an external laser-using device such as a laser processing machine or an ignition plug for an engine using a laser, and in the first embodiment, the spark plug 52 (see FIG. 1) is connected as described above. ) Is connected. The optical fiber 13 is supported by the optical fiber support member 25 and attached to the lens holding member 14.

The optical fiber support member 25 has a cylindrical mounting base portion 25a having a large diameter dimension and a cylindrical support cylinder portion 25b having a small diameter dimension that coincides with the central axis. The mounting base portion 25a has an external dimension that closes the lens holding hole 16 of the back wall 14b. The support cylinder portion 25b has an inner diameter dimension into which the optical fiber 13 is fitted, and in the first embodiment, the optical fiber 13 is passed through while maintaining the airtightness. The optical fiber support member 25 is fixed to the lens holding member 14 (the back wall 14b thereof) with the optical fiber 13 fitted in the support cylinder portion 25b. Then, the optical fiber support member 25 aligns the central axis of the optical fiber 13 (incident end surface 13a thereof) with the central axis of the lens holding hole 16 (condensing lens 23), and causes the incident end surface 13a and the condensing lens 23 to be aligned with each other. Make the intervals appropriate. Therefore, in the optical fiber 13, the laser light as the focused luminous flux passing through the condenser lens 23 is appropriately incident on the incident end surface 13a.

As an example, the laser light emitting device 10 is assembled as follows. First, as shown in FIGS. 3 and 4, the laser array chip 21 is positioned and mounted on the mount portion 17 of the heat diffusion plate 15, and the mounting piece portion 19b is insulated while pressing the tip portion 19c against the mount portion 17. Each electrode piece 19 is provided on the 18th surface. After that, the connection terminal 12a of each electric wire 12 through each electric wire insertion hole 14d (see FIG. 3) of the lower wall 14c of the lens holding member 14 is placed on the mounting piece portion 19b on the insulating member 18 (see FIG. 4). ). Then, as shown in FIG. 4, the screw 26 passed through the ring-shaped connection terminal 12a of each electric wire 12 and the mounting hole 19a of the mounting piece portion 19b of each electrode piece 19 is screwed into the fixing screw hole 18a of the insulating member 18. , Each electric wire 12 and each electrode piece 19 are attached to the insulating member 18. Then, each electric wire 12 (the connection terminal 12a) and each electrode piece 19 (the attachment piece portion 19b) are electrically connected, and the tip portion 19c of each electrode piece 19 is pressed against the mount portion 17. As a result, the laser array chip 21 mounted on the mount portion 17 is electrically connected to each electric wire 12 (the connection terminal 12a thereof) via the mount portion 17 and each electrode piece 19.

Further, as shown in FIG. 3, the condensing lens 23 is inserted into the lens holding hole 16 (the large inner diameter portion 16a) of the back wall 14b of the lens holding member 14 from the flat surface 23b side, and the outer surface 23c is placed on the inner side surface 16c. The flat surface 23b is brought into surface contact with the back end surface 16d while being in surface contact for positioning. At this time, the heat transfer grease 27 is interposed between the lens holding hole 16 (the inner side surface 16c and the back end surface 16d) and the condensing lens 23 (the outer side surface 23c and the flat surface 23b). The heat transfer grease 27 is a lubricant made of a material having high thermal conductivity, and in Example 1, silicon grease is used. Then, the presser ring 24 is inserted into the lens holding hole 16 from behind the condenser lens 23 (on the collimator lens 22 side), and the presser ring 24 is fixed while being pressed against the convex surface 23a of the condenser lens 23 to fix the condenser lens. 23 is positioned and fixed in the lens holding hole 16. A sealing member, which will be described later, may be appropriately provided between the condenser lens 23 and the lens holding hole 16.

After that, the optical fiber support member 25 (the mounting base portion 25a thereof) in which the optical fiber 13 is fitted into the support cylinder portion 25b is attached to the lens holding member 14 (the back wall 14b thereof). At this time, a sealing member such as an elastic body is interposed between the mounting base portion 25a of the optical fiber support member 25 and the back wall 14b of the lens holding member 14. After that, the collimator lens 22 is appropriately provided, and the heat diffusion plate 15 (peripheral portion thereof) is pressed against the open end surface 14a of the lens holding member 14 to attach the heat diffusion plate 15 while closing the open end of the lens holding member 14. At this time, by interposing a sealing member such as an elastic body and the above-mentioned heat transfer grease 27 between the open end surface 14a of the lens holding member 14 and the heat diffusion plate 15 (peripheral portion), the lens holding member 14 and the heat transfer member 14 are heated. It is attached with a reduced thermal resistance while keeping the diffuser plate 15 in a sealed state. Therefore, between the lens holding hole 16 (the inner side surface 16c and the back end surface 16d) and the condensing lens 23 (the outer side surface 23c and the flat surface 23b), the open end surface 14a of the lens holding member 14, and the heat transfer plate 15. The heat transfer grease 27 interposed between them functions as a heat transfer promoting member that reduces the thermal resistance between them. The heat transfer promoting member is interposed between the lens holding hole 16 and the condensing lens 23 and between the lens holding member 14 and the heat diffusion plate 15 in order to reduce the thermal resistance. It suffices, and is not limited to the configuration of the first embodiment.

As a result, as shown in FIGS. 2 and 3, the laser light emitting device 10 is assembled. In the laser light emitting device 10, the lens holding member 14, the heat diffusing plate 15, and the optical fiber support member 25 form a sealed housing 11. Therefore, the lens holding member 14 as the holding member and the heat diffusion plate 15 as the base member form a part of the housing 11 to form a part of the outer shell of the laser light emitting device 10. When the heat diffusion plate 15 is used as the first outer member of the housing 11, the entire outer case is formed in cooperation with the lens holding member 14 which is the second outer member, and the optical fiber support which becomes the third outer member is formed. The optical fiber 13 is attached by the member 25 while maintaining a sealed state. In the housing 11, each electric wire 12 is provided through each electric wire insertion hole 14d (see FIG. 3) of the lower wall 14c of the lens holding member 14, and each electric wire 12 is connected from the housing 11 to an external power supply device. Then, in the laser light emitting device 10, a laser array chip 21 to which electric power is supplied from the power supply device via each electric wire 12 is provided inside the housing 11. In the first embodiment, each electric wire 12 is advanced from the housing 11 to the outside, but an electrode such as each electrode piece 19 may be advanced to the outside of the housing 11. Not limited to 1.

In the laser light emitting device 10, electric power is supplied to the laser array chip 21 from both electric wires 12 connected to an external power supply device via each electrode piece 19 and a mount portion 17. Then, in the laser light emitting device 10, laser light as a divergent light beam is emitted from the laser array chip 21 (its emission surface 21a), and the laser light is converted into a parallel light beam by the collimator lens 22 and proceeds to the condensing lens 23. In the laser light emitting device 10, the condensing lens 23 condenses the laser light as a parallel light beam on the incident end surface 13a of the optical fiber 13, and emits the laser light through the optical fiber 13 at the emission end surface 13b (the other end) (see FIG. 1). )) To output to the outside. As a result, the laser light emitting device 10 can output high-intensity laser light to the laser-using device (ignition plug 52 (see FIG. 1 in the first embodiment)) connected to the other end (emission end surface 13b) of the optical fiber 13. .. For this reason, in the laser light emitting device 10, the laser array chip 21 provided on the heat diffusion plate 15 functions as a laser light source unit.

Here, the laser light emitting device 10 uses a laser array chip 21 formed by providing a plurality of VCSELs in order to output a laser beam having a high intensity (amount of light) even if the size is small. In this laser light emitting device 10, a high current (100 (A) or more in this example) is required to be input in order to appropriately drive the laser array chip 21, that is, to appropriately emit laser light from each VCSEL. .. Therefore, in the laser array chip 21, heat is generated by driving, but if the temperature is high, the life may be shortened and the output may be lowered. For this reason, the laser array chip 21 needs to be driven while being appropriately cooled.

Therefore, in the laser light emitting device 10, the heat absorbing function unit of the cooling device 30 is addressed to the laser array chip 21 as the laser light source unit, and the heat absorbed by the endothermic function unit is dissipated by the heat dissipation function unit of the cooling device 30. Then, the laser array chip 21 is cooled. As the cooling device 30, for example, an air-cooled heat sink as a heat radiating member in which forced convection is formed by an air flow from a blower fan as a blower mechanism can be used. Further, as the cooling device 30, for example, when the temperature of the heat dissipation destination of the heat sink as a heat dissipation member cannot be sufficiently lowered, a thermoelectric element such as a Perche element is provided between the heat diffusion plate 15 and the heat sink. do.

In the laser light emitting device 10 of the first embodiment, as the cooling device 30, the heat diffusion plate 15 forming a part of the housing 11 as the outer shell of the laser light emitting device 10, the Perche element 31 as a thermoelectric element, and the heat radiating member The heat sink 32 and the blower fan 33 as a blower mechanism are used. In this cooling device 30, the heat sink 32 is addressed to the heat diffusion plate 15 via the Pelche element 31, and the blower fan 33 forms an air flow (sends air) toward the heat sink 32 (the heat radiating portion 32b described later). It is configured. In the cooling device 30, the Perche element 31 as the first cooling member cools the heat diffusion plate 15 (the laser array chip 21 provided therein), and the heat sink 32 as the second cooling member cools the Perche element 31. 3 The blower fan 33 as a cooling member cools the heat sink 32.

The Pelche element 31 (thermoelectric element) is located between the heat diffusion plate 15 (heat diffusion member) and the heat sink 32 (heat dissipation member) in order to cool the laser array chip 21 (laser light source unit) to a temperature lower than the ambient temperature. It is provided in. The Pelche element 31 is provided with a cooling surface 31a serving as a heat absorbing portion addressed to the heat diffusion plate 15 and a heat radiating surface 31b serving as a heat radiating portion addressed to a heat sink 32 (the heat absorbing portion 32a described later). The perche element 31 is controlled so as to have a predetermined temperature difference via the power line 31c. The predetermined temperature difference is set by the temperature desired to be maintained in the heat diffusion plate 15 (laser array chip 21 (laser light source unit)) and the temperature at which heat dissipation is possible in the heat sink 32. This is because the temperature at which heat dissipation is possible in the heat sink 32 changes according to the environmental temperature at which the heat sink 32 (the heat radiating portion 32b described later) is installed.

Then, as a preferred example, the Pelche element 31 has a cooling surface 31a interposed therebetween a size corresponding to a portion of the heat diffusion plate 15 where the open end surface 14a of the lens holding member 14 is in surface contact, that is, the heat diffusion plate 15. The size is set so that it can face the open end surface 14a. In the first embodiment, the cooling surface 31a of the Perche element 31 has a shape and dimensions substantially equal to those of the heat diffusion plate 15 (the outer surface thereof), and the heat of the cooling surface 31a is applied to the heat diffusion plate 15 over the entire surface. It faces the open end surface 14a via the diffuser plate 15. This also applies to the heat sink 32 (heat absorbing portion 32a described later), and when the Perche element 31 is not provided, the heat absorbing portion 32a faces the open end surface 14a via the heat diffusion plate 15.

The heat sink 32 dissipates heat from the heat absorbing portion 32a to which the heat radiating surface 31b of the Pelche element 31 is directed and transmitted by the heat radiating portion 32b provided with a plurality of fins 32c (see FIG. 2). The heat sink 32 lowers the temperature of the heat radiating surface 31b of the Pelche element 31 addressed to the endothermic unit 32a by radiating heat from the heat radiating portion 32b to the surrounding air. In the first embodiment, the heat radiating portion 32b is configured by arranging a plurality of fins 32c extending in the vertical direction in parallel in the horizontal direction with FIG. 2 as a front view. A blower fan 33 is provided to cool the heat radiating portion 32b (each fin 32c thereof).

As shown in FIG. 3, the blower fan 33 is configured by providing an intake port 33b and a blower port 33c in a housing that rotatably accommodates the blade portion 33a. The blower fan 33 takes in the surrounding air from the intake port 33b by supplying electric power and rotationally driving the blade portion 33a, and sends the taken-in air out from the blower port 33c in a predetermined direction. Form an air flow in a predetermined direction. The blower fan 33 is provided with a blower port 33c facing the heat radiating portion 32b of the heat sink 32, and causes forced convection in the heat radiating portion 32b to promote heat transfer.

Due to such a configuration, in the laser light emitting device 10 of the first embodiment, the heat diffusion plate 15 forming a part of the housing 11 also functions as the cooling device 30. Then, in the laser light emitting device 10, the heat diffusing plate 15 for diffusing the heat of the provided laser array chip 21 and the endothermic portion 32a of the Perche element 31 addressed to the heat diffusing plate 15 are included in the cooling device 30. It becomes an endothermic function part. Further, in the laser light emitting device 10 of the first embodiment, the heat radiating surface 31b of the Pelche element 31, the heat sink 32 to which the heat radiating surface 31b is addressed, and the blower fan 33 that causes forced convection in the heat radiating portion 32b are cooled. It serves as a heat dissipation function unit of the device 30.

In addition, in the laser light emitting device 10 of the first embodiment, the exterior member 28 is provided so as to surround the lens holding member 14. The exterior member 28 suppresses heat from flowing into the lens holding member 14 from the environment (ambient atmosphere) in which the laser light emitting device 10 (housing 11 (lens holding member 14)) is installed. The exterior member 28 has a lower thermal conductivity than the lens holding member 14, and is formed by using a plastic resin in the first embodiment. In the first embodiment, the exterior member 28 has a rectangular shape with one open end that is in contact with the lens holding member 14 (the outer surface thereof) and surrounds the lens holding member 14 and the optical fiber supporting member 25, and has an optical fiber opening 28a and an electric wire. It has an opening 28b and a cooling opening 28c. The optical fiber opening 28a is a portion through which the optical fiber 13 supported by the optical fiber support member 25 and projected from the lens holding member 14 passes through. The electric wire opening 28b is a place through which the electric wire 12 protruding outward from the housing 11 is passed through the electric wire insertion holes 14d of the lens holding member 14. The cooling opening 28c is a place through which a cooling device 30 for cooling the laser array chip 21 (laser light source portion) is passed, and is formed by an open end. Contact. Therefore, the exterior member 28 covers the lens holding member 14 together with the condensing lens 23 held by the lens holding member 14 over the entire surface, and also covers the endothermic function portion of the cooling device 30 to which the lens holding member 14 is addressed. cover. Then, in the laser light emitting device 10, electric power is supplied from the power supply device via the electric wire 12 in a state where the housing 11 (lens holding member 14) and the optical fiber support member 25 are surrounded by the exterior member 28, and the optical fiber 13 is used. A high-intensity laser beam is output from the other end (emission end surface 13b) of the above.

As shown in FIG. 1, the laser light emitting device 10 constitutes an engine ignition plug system 40 and is used for ignition of an engine 41 as an example of an internal combustion engine. In the engine ignition plug system 40, when the laser light emitting device 10 is driven, the laser light output from the laser array chip 21 is made into parallel light by the collimator lens 22, and the laser light is collected by the condenser lens 23. The light is incident on the incident end surface 13a of the optical fiber 13. Then, the laser beam is incident on the spark plug 52 from the emission end surface 13b through the optical fiber 13. Then, the spark plug 52 irradiates the laser resonator with a laser beam to oscillate a giant pulse, and the pulsed light is focused by an optical element in the combustion chamber 46 of the engine 41 to generate an air breakdown. As a result, the engine ignition plug system 40 ignites the air-fuel mixture in the combustion chamber 46 to drive the engine 41.

Here, in an environment where the engine 41 is provided, for example, in an engine room, the temperature rises mainly due to heat generated from the engine 41. Then, in the laser light emitting device 10, the heat sink 32 as a heat radiating member in the cooling device 30 releases heat to the gas (atmosphere) around the engine 41 at the heat radiating portion 32b, so that the temperature of the gas around the engine 41 causes it to change. The cooling function depends. Here, in the vicinity of the engine 41, although the temperature rise is suppressed by cooling by the cooling water 51 supplied to the cooling water channel 49 and heat dissipation to the atmosphere, the engine 41 (engine outer shell portion 53) generates heat due to combustion. ), So it is a high temperature for arranging the laser array chip 21 (laser light source unit). Therefore, in the laser light emitting device 10 of the first embodiment, as the cooling device 30, in addition to the heat diffusion plate 15 (heat diffusion member), the heat sink 32 (heat dissipation member), and the blower fan 33 (blower mechanism), the Pelche element 31 (blower mechanism) Thermoelectric element) is also used.

In the laser light emitting device 10, since the blower fan 33 takes in the surrounding air from the intake port 33b to form an airflow, the temperature of the airflow (sent air) from the blower fan 33 is the temperature around the engine 41. Become. Therefore, in the laser light emitting device 10, the temperature of the heat sink 32 is higher than the temperature of the air from the blower fan 33 (the temperature around the engine 41), so that the front and back surfaces (cooling surface 31a and heat dissipation surface 31b) of the Perche element 31 are set higher. ), The temperature difference ΔT is controlled. Then, in the laser light emitting device 10, even if the heat sink 32 has a temperature higher than the temperature of the air from the blower fan 33, the heat radiating surface 31b (see FIG. 3) of the perche element 31 can be cooled, and the perche element 31 can be cooled. The cooling surface 31a (see FIG. 3) can be lowered to a temperature sufficient for cooling the laser array chip 21. As a result, in the laser light emitting device 10, even if the ambient atmosphere to be installed is high enough to arrange the laser array chip 21 (laser light source unit), the temperature of the laser array chip 21 can be kept below the target temperature. can.

In the laser light emitting device 10, since the laser array chip 21 outputs a laser beam having a high intensity (light amount), the condenser lens 23 that collects the laser beam absorbs a part of the laser beam as heat energy. , There is a risk that the temperature of the condenser lens 23 will rise. In that case, since the optical performance of the condenser lens 23 is temperature-dependent, there is a risk that the laser light cannot be focused at a predetermined position (in the first embodiment, the incident end surface 13a of the optical fiber 13). It is considered that the temperature dependence of the optical performance of the condenser lens 23 is due to the change in the refractive index and the change in the shape of the condenser lens 23 due to the temperature change. In the laser light emitting device 10, if the incident end surface 13a of the optical fiber 13 cannot be properly focused, all the light beams of the laser light from the laser array chip 21 cannot be incident (introduced) onto the incident end surface 13a. The utilization efficiency of the laser beam is reduced. Therefore, in the laser light emitting device 10, even if the laser array chip 21 (laser light source unit) is appropriately driven, there is a possibility that the target amount of light cannot be output appropriately.

On the other hand, in the laser light emitting device 10, the lens holding member 14 as a holding member for holding the condensing lens 23 has a higher thermal conductivity than the condensing lens 23, and the condensing lens 23 and the cooling device 30 (In Example 1, the heat diffusion plate 15) is in surface contact with the lens. Therefore, in the laser light emitting device 10, the heat of the condensing lens 23 is efficiently transferred to the lens holding member 14, the heat is diffused by the lens holding member 14, and the cooling device 30 efficiently transfers the heat to the lens holding member 14. Cooling. As a result, in the laser light emitting device 10, even if the condensing lens 23 absorbs a part of the laser light as heat energy, the condensing lens 23 can be cooled by the cooling device 30 via the lens holding member 14, so that the collecting lens 23 can be cooled. The rise in temperature of the optical lens 23 can be effectively suppressed.

Here, in the laser light emitting device 10, since the lens holding member 14 has a high thermal conductivity, when the ambient atmosphere to be installed is high temperature, the heat of the peripheral atmosphere flows into the lens holding member 14, and the cooling device 30 There is a risk that the load on the lens array chip 21 (laser light source unit) cannot be cooled properly, or the temperature of the condenser lens 23 rises. Here, assuming that the heat flowing into the lens holding member 14 is Q (W), the Pelche element 31 causes an increase in electric power of about 3Q (W) as compared with the case where the heat does not flow. In particular, in the laser light emitting device 10 of the first embodiment, the laser array chip 21 (laser light source unit) is provided by providing the Perche element 31 (thermoelectric element) in a high temperature environment in which the engine 41 (see FIG. 1) is arranged. Since the laser is cooled, there is a high possibility that a problem will occur due to the inflow of heat into the lens holding member 14.

On the other hand, in the laser light emitting device 10, since the exterior member 28 having a thermal conductivity lower than that of the lens holding member 14 is provided surrounding the lens holding member 14, the lens holding member 14 is provided from the surrounding atmosphere (heat thereof). Can be blocked. Therefore, in the laser light emitting device 10, since the heat of the ambient atmosphere can be suppressed from flowing into the lens holding member 14, the temperature rise of the condenser lens 23 can be suppressed regardless of the temperature of the ambient atmosphere to be installed. As a result, in the laser light emitting device 10, even if a high current is supplied in a high temperature environment to drive the laser array chip 21 (laser light source unit), the temperature rise of the condenser lens 23 can be suppressed more effectively. ..

In the laser light emitting device 10 of the embodiment of the laser light emitting device according to the present disclosure, the lens holding member 14 (holding member) has a higher thermal conductivity than the condensing lens 23 to hold, and the condensing lens 23 and cooling It comes into surface contact with the device 30 (heat diffusion plate 15 in Example 1). Therefore, in the laser light emitting device 10, the condensing lens 23 and the cooling device 30 (heat diffusion plate 15) can be thermally connected via the lens holding member 14 (holding member). As a result, in the laser light emitting device 10, even if the condensing lens 23 absorbs a part of the laser light as heat energy, the condensing lens 23 can be cooled by the cooling device 30 via the lens holding member 14, so that the collecting lens 23 can be cooled. The rise in temperature of the optical lens 23 can be effectively suppressed. Therefore, the laser light emitting device 10 can prevent a change in the optical performance of the condenser lens 23 due to a change in the refractive index or a change in the shape due to a temperature change, and can appropriately output a target amount of light.

Further, in the laser light emitting device 10, the temperature rise of the condenser lens 23 is suppressed by bringing the lens holding member 14 into surface contact with the cooling device 30 for cooling the laser array chip 21 (laser light source unit). Therefore, in the laser light emitting device 10, the laser array chip 21 (laser light source unit) is suitable with a simple configuration that does not invite the addition of a new cooling member only for suppressing the temperature rise of the condenser lens 23. It is possible to cool the lens 23 and suppress an increase in the temperature of the condenser lens 23.

Further, in the laser light emitting device 10, since the lens holding member 14 has a high thermal conductivity, the heat can be diffused even if the condensing lens 23 absorbs the heat energy, so that heat is generated in the peripheral portion of the lens holding hole 16. Can be prevented from accumulating. Then, in the laser light emitting device 10, the temperature rise of the entire lens holding member 14 can be suppressed by bringing the lens holding member 14 into surface contact with the cooling device 30, and the entire lens holding member 14 including the lens holding hole 16 can be suppressed. Deformation due to temperature rise can be prevented. Therefore, in the laser light emitting device 10, the laser beam is placed at a predetermined position due to the displacement of the condenser lens 23 due to the deformation of the lens holding member 14 (lens holding hole 16) (in the first embodiment, the incident end surface 13a of the optical fiber 13). ) Can be prevented from being unable to collect light, and the target amount of light can be output appropriately.

In the laser light emitting device 10, a Perche element 31 (thermoelectric element) is provided as a cooling device 30 for cooling the laser array chip 21 (laser light source unit) in addition to the heat diffusion plate 15, the heat sink 32, and the blower fan 33. Therefore, in the laser light emitting device 10, the laser array chip 21 (laser light source unit) and the condensing lens are dissipated by the heat sink 32 by controlling the temperature difference between the front and back surfaces of the perche element 31 even in a high temperature environment. 23 can be cooled. As a result, in the laser light emitting device 10, for example, even in an environment where an engine 41 (see FIG. 1) such as an engine room is provided and the temperature is high, the laser array chip 21 (laser light source unit) is moved from the ambient temperature. Can be cooled to a low temperature, and the temperature rise of the condenser lens 23 can be suppressed.

In the laser light emitting device 10, the condensing lens 23 is a plano-convex lens, and the flat surface 23b is brought into surface contact with the back end surface 16d of the lens holding hole 16 of the lens holding member 14, whereby the condensing lens 23 and the lens holding member 14 are brought into surface contact with each other. It is in surface contact. Therefore, in the laser light emitting device 10, the condensing lens 23 can be brought into surface contact with the lens holding member 14 while positioning the condensing lens 23 with a simple configuration.

In the laser light emitting device 10, the outer surface 23c of the condensing lens 23, which is a plano-convex lens, is brought into surface contact with the inner surface 16c of the large inner diameter portion 16a of the lens holding hole 16 of the lens holding member 14, so that the condensing lens 23 and the condensing lens 23 are brought into contact with each other. The lens holding member 14 is in surface contact with the lens holding member 14. Therefore, in the laser light emitting device 10, the condensing lens 23 can be brought into surface contact with the lens holding member 14 while positioning the condensing lens 23 with a simple configuration. In addition, in the laser light emitting device 10, the flat surface 23b of the condensing lens 23 as a plano-convex lens is brought into surface contact with the back end surface 16d of the lens holding member 14, and the outer surface 23c of the condensing lens 23 is brought into contact with the lens holding member 14. It is in surface contact with the inner surface 16c. Therefore, in the laser light emitting device 10, the contact area between the condenser lens 23 and the lens holding hole 16 (lens holding member 14) can be increased. In particular, in the laser light emitting device 10, the dimension seen in the direction in which the central axis of the lens holding hole 16 (inner side surface 16c) extends is larger than the dimension of the outer surface 23c of the condenser lens 23 seen in the direction in which the central axis extends. It's getting bigger. Therefore, in the laser light emitting device 10, the outer surface 23c of the condenser lens 23 can be brought into surface contact with the lens holding hole 16 (inner side surface 16c) over the entire area, and the condenser lens 23 and the lens holding hole 16 (inner side surface) can be brought into surface contact with each other. The contact area with 16c) can be increased. As a result, in the laser light emitting device 10, the heat transfer path between the condenser lens 23 and the lens holding hole 16 can be increased, and the temperature rise of the condenser lens 23 can be suppressed more appropriately.

In the laser light emitting device 10, the condensing lens 23 and the cooling device 30 (heat diffusion plate 15 in the first embodiment) are surfaced on the lens holding member 14 (holding member) by interposing a heat transfer grease 27 as a heat transfer promoting member. I'm in contact. Therefore, in the laser light emitting device 10, the thermal resistance between the condensing lens 23 and the cooling device 30 in surface contact with the lens holding member 14 can be further reduced, so that the temperature rise of the condensing lens 23 can be suppressed more appropriately. can. Further, since the laser light emitting device 10 uses the heat transfer grease 27 as the heat transfer promoting member, the work of inserting the condensing lens 23 into the lens holding hole 16 can be facilitated.

In the laser light emitting device 10, the antireflection processing film 23d is provided on the outer surface of the condensing lens 23 composed of the convex surface 23a, the flat surface 23b, and the outer surface 23c. Here, the antireflection treated film 23d may not be able to exhibit appropriate performance due to thermal stress caused by the difference in thermal expansion from the condensing lens 23 caused by the temperature rise and deterioration caused by the temperature rise. be. In the laser light emitting device 10, since the lens holding member 14 (holding member) comes into surface contact with the antireflection processing film 23d on the outer surface of the condenser lens 23, the temperature rise of the antireflection treatment film 23d can also be suppressed. As a result, in the laser light emitting device 10, it is possible to prevent a change in optical performance due to a temperature rise of the condenser lens 23, and it is possible to prevent the laser light emitting device 10 from being unable to exhibit its performance due to a temperature rise of the antireflection processing film 23d. The target amount of light can be output more appropriately.

In the laser light emitting device 10, an exterior member 28 having a thermal conductivity lower than that of the lens holding member 14 is provided so as to surround the lens holding member 14. Therefore, in the laser light emitting device 10, even if the environment in which the laser light emitting device 10 is installed is a high temperature atmosphere, the inflow of heat from the environment (ambient atmosphere) to the lens holding member 14 can be suppressed. As a result, the laser light emitting device 10 can suppress the heat of the ambient atmosphere from flowing into the lens holding member 14 regardless of the temperature of the ambient atmosphere to be installed, and can appropriately suppress the temperature rise of the condenser lens 23. .. Further, in the laser light emitting device 10, since it is possible to suppress the heat of the ambient atmosphere from flowing into the lens holding member 14, it is possible to suppress an increase in the load on the cooling device 30 (mainly the Perche element 31 (thermoelectric element)), and the laser array. The chip 21 (laser light source unit) can be appropriately cooled. In particular, in the laser light emitting device 10, the exterior member 28 surrounds the condensing lens 23 and the optical fiber support member 25 together with the lens holding member 14. Therefore, in the laser light emitting device 10, it is possible to suppress the heat of the ambient atmosphere from flowing into the condensing lens 23 and flowing into the lens holding member 14 and the condensing lens 23 via the optical fiber support member 25. The rise in temperature of the optical lens 23 can be suppressed more appropriately.

In the laser light emitting device 10, the lens holding member 14 and the optical fiber support member 25 are surrounded by the exterior member 28. Therefore, in the laser light emitting device 10, even if the optical fiber support member 25 is formed of a material having high thermal conductivity such as a metal material in order to appropriately support the optical fiber 13, light is emitted from the environment (ambient atmosphere). The inflow of heat into the fiber support member 25 can be suppressed.

In the laser light emitting device 10, the cooling opening 28c of the exterior member 28 is brought into contact with the cooling surface 31a (heat absorbing portion) of the Perche element 31 which is the heat absorbing function portion of the cooling device 30, and the lens holding member 14 is surrounded by the exterior member 28. There is. Here, in the laser light emitting device 10, the laser array chip 21 (laser light source unit) and the lens holding member 14 are cooled to a temperature lower than the ambient temperature by providing the Perche element 31 (thermoelectric element). Therefore, in the laser light emitting device 10, together with the lens holding member 14 cooled by the cooling device 30, the cold portion (endothermic function unit) in the cooling device 30 can be shielded from the ambient atmosphere (heat thereof), and the temperature of the condenser lens 23 can be increased. The rise can be suppressed more appropriately.

The laser light emitting device 10 uses a laser array chip 21 in which a plurality of surface emitting lasers are arranged as a laser light source unit. Here, if the surface-emitting semiconductor lasers are arranged at a high density, heat is generated at a high density due to the concentration of heat sources. However, in the laser light emitting device 10, the cooling device 30 (heat diffusion plate 15 in the first embodiment) is attached to the laser array chip 21 (laser light source unit), and the cooling device 30 (heat diffusion plate 15) is lensed. The holding member 14 is in surface contact. Therefore, in the laser light emitting device 10, the temperature rise of the condenser lens 23 can be appropriately suppressed while appropriately cooling the laser array chip 21 (laser light source unit). In particular, in the laser light emitting device 10, the laser array chip 21 is located near the center of the cooling surface 31a of the Pelche element 31 (the same applies to the heat sink 32), which is the position where the cooling intensity is highest (cooling center position) in the cooling device 30. The mount portion 17 provided with the above is brought close to each other. Then, in the laser light emitting device 10, the lens holding member 14 (open end surface 14a thereof) is brought into surface contact with the peripheral edge of the cooling surface 31a of the cooling device 30. Therefore, in the laser light emitting device 10, the laser array chip 21 (laser light source unit), which is most required to be cooled, is cooled at the cooling center position of the cooling device 30, so that the laser array chip 21 (laser light source unit) is cooled. ) Can be cooled without impairing the cooling function of the condenser lens 23.

In the laser light emitting device 10, the lens holding member 14 (open end surface 14a thereof) is brought into surface contact with the heat diffusion plate 15 provided with the laser array chip 21 (laser light source unit). Therefore, in the laser light emitting device 10, the perche element 31 (cooling surface 31a thereof) can be addressed over the entire surface of the heat diffusion plate 15, so that the laser array chip 21 (laser light source unit) can be addressed via the heat diffusion plate 15. ) And the condenser lens 23 can be cooled appropriately.

In the engine spark plug system 40 of one embodiment of the engine spark plug system according to the present disclosure, the laser light source unit (laser array chip 21) and the condenser lens 23 can be appropriately cooled. Therefore, in the engine spark plug system 40, it is possible to prevent the life of the laser light source unit (laser array chip 21) from being shortened and the output from being lowered even in a high temperature environment, and it is possible to prevent the output of the internal combustion engine from being shortened. The engine 41 as an example can be appropriately ignited.

Therefore, in the laser light emitting device 10 of the first embodiment as the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the above-described first embodiment, the laser light emitting device 10 of the first embodiment as an example of the laser light emitting device according to the present disclosure has been described, but the laser light source unit that emits the laser light and the laser light source unit that emits the laser light emit the laser light. A condensing lens that condenses the laser beam at a predetermined position, a holding member that holds the condensing lens while in surface contact with the condensing lens, and a laser light source unit for cooling the laser light source unit. The holding member may be a laser light emitting device having a higher thermal conductivity than the condensing lens and in surface contact with the cooling device, and is limited to the above-described first embodiment. Not done.

Further, in the above-described first embodiment, the open end surface 14a of the lens holding member 14 is brought into surface contact with the heat diffusion plate 15 that also functions as the cooling device 30, but the laser light emitting device 10A shown in FIG. 5 may be configured. .. In the laser light emitting device 10A, the heat sink 32 (the heat absorbing portion 32a thereof) has the open end surface 14a of the lens holding member 14 as the cooling device 30 so that the heat diffusing plate 15A can be fitted inside the lens holding member 14. ) Is in surface contact. Since the laser light emitting device 10A basically has the same configuration as the laser light emitting device 10 of the first embodiment, basically the same effect as that of the first embodiment can be obtained. In addition, in the laser light emitting device 10A, the cooling intensity of the peripheral portion of the cooling surface 31a of the Perche element 31 is relatively low, but the open end surface 14a of the lens holding member 14 is brought into direct surface contact with the peripheral portion. Therefore, the temperature rise of the condenser lens 23 can be suppressed more appropriately.

Further, in the above-described first embodiment, the heat diffusion plate 15 and the heat sink 32 are separately configured in the cooling device 30, but the laser light emitting device 10B shown in FIG. 6 may be configured. The laser light emitting device 10B uses a heat sink 32B in which a heat diffusion plate (15) and a heat sink (32) are integrated, and a laser array chip 21 is provided on the heat absorbing portion 32Ba. The heat sink 32B also has a function of efficiently diffusing the heat generated by the laser array chip 21 provided in the same manner as the heat diffusion plate 15, and such a function has, for example, the thermal conductivity of a metal material or the like. It can be realized by forming using a material having high (thermal conductivity), and in the example of FIG. 6, it is formed by using copper. Since the laser light emitting device 10B basically has the same configuration as the laser light emitting device 10 of the first embodiment, basically the same effect as that of the first embodiment can be obtained. In addition, the laser light emitting device 10B can eliminate the heat resistance between the heat diffusing plate 15 and the heat sink 32 in the laser light emitting device 10 while having a simple configuration, and the laser array chip 21 (laser light source unit) can be made more. It is possible to more appropriately suppress an increase in the temperature of the condenser lens 23 while appropriately cooling the condenser lens 23. Even when the heat sink 32B is used, the open end surface 14a of the lens holding member 14 may be brought into direct surface contact with the heat sink 32B (the endothermic portion 32Ba thereof) as in the laser light emitting device 10A of FIG. ..

In the above-described first embodiment, the air-cooled heat sink 32 is used as the cooling device 30, but the laser light emitting device 10C shown in FIG. 7 may be configured. The laser light emitting device 10C uses a liquid-cooled heat sink 32C. In the heat sink 32C, a heat absorbing portion 32Ca is defined by a heat absorbing block 32Cd in which a refrigerant passage 32Ce is formed, and cooling water is appropriately supplied to the refrigerant passage 32Ce. As the cooling water, the cooling water 51 supplied to the cooling water channel 49 of the engine ignition plug system 40 may be used, or may be supplied from another source. In this laser light emitting device 10C, other configurations are the same as those of the laser light emitting device 10 of the first embodiment, and basically the same effect as that of the first embodiment can be obtained. Even when the heat sink 32C is used, the open end surface 14a of the lens holding member 14 may be brought into direct surface contact with the heat sink 32C (the endothermic portion 32Ca thereof) as in the laser light emitting device 10A of FIG. ..

In the examples shown in Example 1 and FIGS. 5 to 7 described above, the condenser lens 23 was inserted into the lens holding hole 16 of the lens holding member 14 from the laser array chip 21 (laser light source unit) side, but FIG. 8 The laser light emitting device 10D shown in the above may be configured. In the laser light emitting device 10D, the lens holding hole 16D of the lens holding member 14D is configured to be opposite to the lens holding hole 16 of the laser light emitting device 10 of the first embodiment in the optical axis direction, and the lens holding member 14D The condensing lens 23 (the plane 23b thereof) is inserted into the lens holding hole 16D from the outside of the lens. Since the laser light emitting device 10D has the same other configurations as the laser light emitting device 10 of the first embodiment, basically the same effect as that of the first embodiment can be obtained. Even when the condensing lens 23 is oriented in the opposite direction, the open end surface 14a of the lens holding member 14 is used as the heat sink 32C (heat absorbing portion 32Ca) of the lens holding member 14 as in the laser light emitting device 10A of FIG. Direct surface contact may be used, an integrated heat sink 32B may be used as in the laser light emitting device 10B of FIG. 6, or a liquid-cooled heat sink 32C may be used as in the laser light emitting device 10C of FIG. good.

In Examples 1, FIGS. 5 to 8 and 11 described above, and Examples 2 to 6 described later, the condenser lens 23 has a plano-convex shape, but the laser beam passing through the collimator lens 22 is used. Other configurations may be used as long as the light is focused and incident on a predetermined position (in each example, the incident end surface 13a of the optical fiber 13). As another configuration, for example, when the condensing lens has a biconvex shape, the outer surface connecting the two convex surfaces is made a surface parallel to the optical axis, as in the outer surface 23c, so that the lens holding member 14 has a biconvex shape. The lens holding hole 16 (inner side surface 16c thereof) can be brought into surface contact with the lens holding hole 16. Further, the condenser lens and the lens holding hole may be brought into surface contact with each other so that the shape of the lens holding hole (the portion corresponding to the back end surface 16d) of the lens holding member 14 follows a curved surface such as a convex surface. .. Further, in the above-mentioned Examples 1 and the examples shown in FIGS. 5 to 8, the condenser lens 23 was formed of a glass material, but the laser light passing through the collimator lens 22 is condensed and placed at a predetermined position (optical fiber). As long as it is incident on the incident end face 13a) of 13, it may be formed of a resin material or another material, and is not limited to the configuration of each of the above examples.

In Examples 1, FIG. 5, FIG. 7, and FIG. 8 described above, and in Examples 2 and 3 described later, a Perche element 31 is used as the thermoelectric element as the cooling device 30. However, the thermoelectric element is appropriately determined in consideration of the temperature required for the laser array chip 21 (laser light source unit), the temperature of the ambient atmosphere, and the cooling function of the heat sink 32 (radiating member) and the blower fan 33 (blower mechanism). It may be provided, and is not limited to the configuration of each of the above examples. Further, the thermoelectric element may be provided between the laser light source unit and the heat radiating member (heat sink 32) in order to cool the laser light source unit (laser array chip 21) to a temperature lower than the ambient temperature. The present invention is not limited to the first embodiment. This is the case with the blower fan 33 as the blower mechanism of the cooling device 30 provided in the above-mentioned Example 1 and the examples shown in FIGS. 5, 6 and 8, and the examples shown in Example 1 and FIGS. 5 to 8. The same applies to the provided exterior member 28.

In the examples shown in Example 1 and FIGS. 5 to 8 described above, an example in which laser light is used for ignition of an internal combustion engine has been shown, but the emission end face 13b of the optical fiber 13 is to be used in a laser-using device such as a laser processing machine. (The other end) may be connected to the laser-using device, and the present invention is not limited to the above-described first embodiment.

Next, the laser light emitting device 10E of the second embodiment, which is one embodiment of the present disclosure, will be described with reference to FIGS. 9 and 10. The laser light emitting device 10E is an example in which a part of the configuration is different from that of the laser light emitting device 10 of the first embodiment. Since the laser emitting device 10E has the same basic concept, configuration, and effect as the laser emitting device 10 of the first embodiment shown in FIGS. 1 to 4, the same reference numerals are given to the parts having the same configuration, and the details are detailed. The description is omitted.

The laser light emitting device 10E of the second embodiment enhances the accuracy of cooling of the laser light source unit (laser array chip 21) and the condenser lens 23 by the cooling device 30 as compared with the first embodiment. As shown in FIG. 9, the laser light emitting device 10E has a thermistor 61 and a temperature control device 62. The thermista 61 is a laser output mechanism that outputs laser light in the laser light emitting device 10E, that is, the temperature of a laser light source unit (laser array chip 21), a heat diffusion plate 15 provided with the laser light source unit, a condensing lens 23, a lens holding member 14, and the like. This is an example of a temperature detection unit that detects. In the second embodiment, the thermistor 61 is provided to detect the temperature t1 of the heat diffusion plate 15 in the laser output mechanism, and measures the temperature t1 (the signal) detected via the detection line 61a connected to the thermistor 61. It is sent to the control device 62. Along with this, the exterior member 28 is provided with a detection opening 28d through which the detection line 61a passes.

The temperature control device 62 is provided for adjusting the amount of heat radiated in the heat radiating function unit of the cooling device 30 (the heat radiating surface 31b of the Pelche element 31 (thermoelectric element), the heat sink 32, and the blower fan 33 (blower mechanism)). The temperature control device 62 of the second embodiment is supposed to control the temperature of the perche element 31, and the power line 31c of the perche element 31 is connected and the detection line 61a of the thermistor 61 is connected. The temperature control device 62 adjusts the temperature of the cooling surface 31a addressed to the heat diffusion plate 15 so that the heat diffusion plate 15 becomes a preset target temperature T1 based on the temperature t1 detected by the thermistor 61. do. That is, when the temperature t1 is higher than the target temperature T1, the temperature control device 62 is not sufficiently cooled, so the temperature of the cooling surface 31a is lowered, and when the temperature t1 is lower than the target temperature T1, the temperature control device 62 is excessively cooled. Therefore, the temperature of the cooling surface 31a is raised (cooling is relaxed). At this time, the temperature of the cooling surface 31a may be adjusted according to the difference between the temperature t1 and the target temperature T1, or may be adjusted to a predetermined temperature regardless of the difference. In the first embodiment, the temperature of the cooling surface 31a is adjusted by controlling the current value or the like supplied from the power line 31c. The target temperature T1 may be a numerical value at one point or may have a predetermined width (range).

Next, in the laser light emitting device 10E, an example of a temperature control process in which the temperature control device 62 controls the temperature of the Perche element 31 for adjusting the cooling temperature will be described with reference to FIG. The temperature control process is executed by the temperature control device 62 based on the program stored in the built-in memory. Hereinafter, each step (each step) of the flowchart of FIG. 10 will be described. This flowchart is started when the laser light emitting device 10E is driven and the temperature control device 62 controls the Pelche element 31 so that the cooling surface 31a and the heat radiating surface 31b have a set predetermined temperature difference.

In step S1, the temperature t1 is acquired from the thermistor 61, and the process proceeds to step S2.

In step S2, it is determined whether or not the temperature t1 is the same as the target temperature T1, and if YES, the process proceeds to step S3, and if NO, the process proceeds to step S4. In step S2, when the target temperature T1 has a predetermined width, it is determined whether or not the temperature t1 is within the target temperature T1.

In step S3, the temperature of the cooling surface 31a is maintained, and the process proceeds to step S7. In step S3, since the temperature t1 is the same as the target temperature T1, the control of the Pelche element 31 performed at this point, that is, the temperature of the cooling surface 31a is maintained.

In step S4, it is determined whether or not the temperature t1 is higher than the target temperature T1, and if YES, the process proceeds to step S5, and if NO, the process proceeds to step S6.

In step S5, the temperature of the cooling surface 31a is lowered, and the process proceeds to step S7. In step S5, the temperature of the cooling surface 31a is lowered so that the heat diffusion plate 15 reaches the target temperature T1.

In step S6, the temperature of the cooling surface 31a is raised, and the process proceeds to step S7. In step S6, the temperature of the cooling surface 31a is raised so that the heat diffusion plate 15 reaches the target temperature T1.

In step S7, it is determined whether or not the laser light emitting device 10E has been stopped. If YES, this temperature control process is terminated, and if NO, the process proceeds to step S8. In step S7, it is determined whether or not the laser light emitting device 10E is stopped, that is, whether or not it is necessary for the cooling device 30 to cool the laser light source unit (laser array chip 21).

In step S8, it is determined whether or not the sampling interval is Δt, and if YES, the process returns to step S1, and if NO, step S8 is repeated. In step S8, the process waits until the elapsed time from the acquisition of the temperature t1 in step S1 reaches the sampling interval Δt, and returns to step S1 when the sampling interval Δt is reached.

When the laser light emitting device 10E is driven, the cooling device 30 starts cooling the laser light source unit (laser array chip 21). At that time, the temperature control device 62 performs the temperature control process shown in the flowchart of FIG. 10 so that the heat diffusion plate 15 becomes the target temperature T1 based on the temperature t1 detected by the thermistor 61. The temperature of the cooling surface 31a is adjusted. As a result, the cooling device 30 can always keep the temperature of the heat diffusion plate 15 in the vicinity of the target temperature T1, can cool the laser light source unit (laser array chip 21) more appropriately, and hold the lens holding member 14 (holding). The condenser lens 23 can be cooled more appropriately via the member).

Since the laser light emitting device 10E of the second embodiment basically has the same configuration as the laser light emitting device 10 of the first embodiment, basically the same effect as that of the first embodiment can be obtained.

In addition, in the laser light emitting device 10E, the temperature control device 62 adjusts the temperature of the cooling surface 31a of the Pelche element 31 so that the heat diffusion plate 15 becomes the target temperature T1 based on the temperature t1 detected by the thermistor 61. Therefore, the laser light source unit (laser array chip 21) and the condenser lens 23 can be cooled more appropriately.

Therefore, in the laser light emitting device 10E of the second embodiment of the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the second embodiment described above, the temperature of the perche element 31 (cooling surface 31a thereof) was controlled based on the temperature t1 of the heat diffusion plate 15 detected by the thermistor 61, but the laser light emitting device shown in FIG. 11 It may be configured on the 10th floor. In the laser light emitting device 10F, a thermistor 63 is provided to detect the temperature t2 of the lens holding member 14 in the laser output mechanism. Along with this, the exterior member 28 is provided with a detection opening 28e through which the detection line 63a of the thermistor 63 passes instead of the detection opening 28d. In the laser light emitting device 10F, the temperature control device 62F sets the temperature of the cooling surface 31a of the Pelche element 31 so that the lens holding member 14 becomes the preset target temperature T2 based on the temperature t2 detected by the thermistor 63. Adjust. Since the laser light emitting device 10F basically has the same configuration as the laser light emitting device 10E of the second embodiment, basically the same effect as that of the second embodiment can be obtained. In addition, in the laser light emitting device 10F, since the temperature of the cooling surface 31a is adjusted so that the lens holding member 14 reaches the target temperature T2, the condenser lens 23 can be cooled more appropriately.

Next, the laser light emitting device 10G of the third embodiment, which is one embodiment of the present disclosure, will be described with reference to FIGS. 12 and 13. The laser light emitting device 10G is an example in which a part of the configuration is different from that of the laser light emitting device 10 of the first embodiment. Since the laser light emitting device 10G has the same basic concept, configuration, and effect as the laser light emitting device 10 of the first embodiment shown in FIGS. 1 to 4, the same reference numerals are given to the parts having the same configuration, and the details are detailed. The description is omitted.

In the laser light emitting device 10G of the third embodiment, the accuracy of cooling the laser light source unit (laser array chip 21) and the condensing lens 23 by the cooling device 30 is based on the same concept as that of the laser light emitting device 10E of the second embodiment. It enhances more than. As shown in FIG. 12, the laser light emitting device 10G includes a thermistor 61, a thermistor 63, and a temperature control device 62G. The thermistor 61 is the same as that shown in FIG. 9 of Example 2, and the thermistor 63 is the same as that shown in FIG. 11, which is another example of Example 2.

The temperature control device 62G is basically the same as that shown in FIGS. 9 and 11 of the second embodiment, and the detection line 61a of the thermistor 61 and the detection line 63a of the thermistor 63 are connected to each other. The temperature control device 62G adjusts the temperature of the cooling surface 31a so that the lens holding member 14 becomes the preset target temperature T2 in the normal state where the heat diffusion plate 15 is the preset target temperature T1. Further, the temperature control device 62G switches the control so as to adjust the temperature of the cooling surface 31a so that the heat diffusion plate 15 becomes the target temperature T1 when the heat diffusion plate 15 becomes a temperature higher than the target temperature T1. In other words, the temperature control device 62G operates in the same manner as the laser light emitting device 10F in FIG. 11 under normal conditions, and when the heat diffusion plate 15 reaches a temperature higher than the desired temperature, the temperature control device 62G operates in the same manner as the laser light emitting device 10E in FIG. Operate. At this time, the temperature of the cooling surface 31a may be adjusted according to the difference between the detected temperature (t1, t2) and the target temperature (T1, T2), or may be adjusted to a predetermined temperature regardless of the difference. .. Here, as a scene where the heat diffusion plate 15 has a temperature higher than a desired temperature, for example, it is conceivable that heat generation increases due to an increase in electrical resistance due to deterioration of the electric circuit over time. As a result, the temperature control device 62G prevents defects and rapid shortening of the life due to the laser light source unit (laser array chip 21) becoming excessively high in temperature.

Next, in the laser light emitting device 10G, an example of the temperature control process in which the temperature control device 62G controls the temperature of the Pelche element 31 for adjusting the cooling temperature will be described with reference to FIG. The temperature control process is basically the same as the temperature control process shown in the flowchart of FIG. 10, and is executed by the temperature control device 62G based on the program stored in the built-in memory. Hereinafter, each step (each step) of the flowchart of FIG. 13 will be described.

In step S11, the temperature t1 is acquired from the thermistor 61 and the temperature t2 is acquired from the thermistor 63, and the process proceeds to step S12.

In step S12, it is determined whether or not the temperature t1 is higher than the target temperature T1, and if YES, the process proceeds to step S13, and if NO, the process proceeds to step S14.

In step S13, the temperature of the cooling surface 31a is lowered so as to be the target temperature T1, and the process proceeds to step S19. In step S13, the temperature of the cooling surface 31a is lowered so that the heat diffusion plate 15 reaches the target temperature T1.

In step S14, it is determined whether or not the temperature t1 is the same as the target temperature T1, and if YES, the process proceeds to step S15, and if NO, the process proceeds to step S16.

In step S15, the temperature of the cooling surface 31a is maintained, and the process proceeds to step S19.

In step S16, it is determined whether or not the temperature t2 is higher than the target temperature T2, and if YES, the process proceeds to step S17, and if NO, the process proceeds to step S18.

In step S17, the temperature of the cooling surface 31a is lowered so as to set the target temperature T2, and the process proceeds to step S19. In step S17, the temperature of the cooling surface 31a is lowered so that the lens holding member 14 reaches the target temperature T2.

In step S18, the temperature of the cooling surface 31a is raised so as to be the target temperature T2, and the process proceeds to step S19. In step S18, the temperature of the cooling surface 31a is raised so that the lens holding member 14 reaches the target temperature T2.

In step S19, it is determined whether or not the laser light emitting device 10G has been stopped. If YES, this temperature control process is terminated, and if NO, the process proceeds to step S20.

In step S20, it is determined whether or not the sampling interval is Δt, and if YES, the process returns to step S11, and if NO, step S20 is repeated.

When the laser light emitting device 10G is driven, the cooling device 30 starts cooling the laser light source unit (laser array chip 21). At that time, the temperature control device 62G performs the temperature control process shown in the flowchart of FIG. 13, and when the temperature t1 of the heat diffusion plate 15 is lower than the target temperature T1, the temperature control device 62G is based on the temperature t2 detected by the thermistor 63. The temperature of the cooling surface 31a is adjusted so that the lens holding member 14 reaches the target temperature T2. Further, the temperature control device 62G performs the temperature control process so that when the temperature t1 of the heat diffusion plate 15 becomes higher than the target temperature T1, the temperature of the cooling surface 31a becomes the target temperature T1 of the heat diffusion plate 15. Lower. As a result, in the cooling device 30, the temperature of the lens holding member 14 can always be in the vicinity of the target temperature T2 under the normal state, and the temperature of the heat diffusion plate 15 can be made lower than the target temperature T1. The light source unit (laser array chip 21) and the condenser lens 23 can be cooled more appropriately.

Since the laser light emitting device 10G of the third embodiment basically has the same configuration as the laser light emitting device 10 of the first embodiment, basically the same effect as that of the first embodiment can be obtained.

In addition, the laser light emitting device 10G adjusts the temperature of the cooling surface 31a of the Pelche element 31 so that the lens holding member 14 becomes the target temperature T2 while keeping the temperature of the heat diffusion plate 15 lower than the target temperature T1. Therefore, the laser light source unit (laser array chip 21) and the condenser lens 23 can be cooled more appropriately.

Therefore, in the laser light emitting device 10G of the third embodiment of the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the second and third embodiments, the thermistor 61 and the thermistor 63 are provided in the laser light emitting device 10 of FIG. 3, but the laser light emitting device 10A of FIG. 5 and the laser light emitting device 10D of FIG. 8 may be provided. , The configuration of Example 2 and Example 3 is not limited.

Next, the laser light emitting device 10H of the fourth embodiment, which is one embodiment of the present disclosure, will be described with reference to FIGS. 14 and 15. The laser light emitting device 10H is an example in which the thermistor 61 and the temperature control device 62H are provided in the laser light emitting device 10B shown in FIG. Since the laser light emitting device 10H has the same basic concept, configuration, and effect as the laser light emitting device 10B of FIG. 6, the same reference numerals are given to the parts having the same configuration, and detailed description thereof will be omitted.

In the laser light emitting device 10H of the fourth embodiment, the accuracy of cooling the laser light source unit (laser array chip 21) and the condensing lens 23 by the cooling device 30 is based on the same concept as that of the laser light emitting device 10E of the second embodiment. It is higher than the laser light emitting device 10B of. As shown in FIG. 14, the laser light emitting device 10H has a thermistor 61 and a temperature control device 62H similar to those in the second embodiment. The thermistor 61 is an example of a temperature detection unit that detects the temperature t3 of the endothermic unit 32Ba of the heat sink 32B in the laser output mechanism, and sends the temperature t3 detected via the detection line 61a to the temperature control device 62H.

The temperature control device 62H controls the air volume (rotation speed) from the blower fan 33 (blower mechanism) in the heat dissipation function unit of the cooling device 30, and the power line 33d of the blower fan 33 is connected and the thermistor. The detection line 61a of 61 is connected. The temperature control device 62H adjusts the air volume from the blower fan 33 so that the endothermic unit 32Ba reaches the preset target temperature T3 based on the temperature t3 detected by the thermistor 61. That is, the temperature control device 62 increases the air volume from the blower fan 33 when the temperature t3 is higher than the target temperature T3, and decreases the air volume from the blower fan 33 when the temperature t3 is lower than the target temperature T3. At this time, the air volume from the blower fan 33 may be adjusted according to the difference between the temperature t3 and the target temperature T3, or may be adjusted to a predetermined air volume regardless of the difference. The target temperature T3 may be a numerical value at one point or may have a predetermined width (range).

Next, in the laser light emitting device 10H, an example of a temperature control process in which the temperature control device 62H controls the air volume of the blower fan 33 for adjusting the cooling temperature will be described with reference to FIG. The temperature control process is basically the same as the temperature control process shown in the flowchart of FIG. 10, and is executed by the temperature control device 62H based on the program stored in the built-in memory. Hereinafter, each step (each step) of the flowchart of FIG. 15 will be described.

Step S31 acquires the temperature t3 from the thermistor 61 and proceeds to step S32.

Step S32 determines whether or not the temperature t3 is the same as the target temperature T3. If YES, the process proceeds to step S33, and if NO, the process proceeds to step S34.

Step S33 maintains the air volume of the blower fan 33 and proceeds to step S37.

Step S34 determines whether or not the temperature t3 is higher than the target temperature T3. If YES, the process proceeds to step S35, and if NO, the process proceeds to step S36.

In step S35, the air volume of the blower fan 33 is increased, and the process proceeds to step S37.

In step S36, the air volume of the blower fan 33 is reduced, and the process proceeds to step S37.

In step S37, it is determined whether or not the laser light emitting device 10H has been stopped. If YES, this temperature control process is terminated, and if NO, the process proceeds to step S38.

Step S38 determines whether or not the sampling interval has reached Δt. If YES, the process returns to step S31, and if NO, step S38 is repeated.

When the laser light emitting device 10H is driven, the cooling device 30 starts cooling the laser light source unit (laser array chip 21). At that time, the temperature control device 62H performs the temperature control process shown in the flowchart of FIG. 15 so that the heat absorbing portion 32Ba of the heat sink 32B becomes the target temperature T3 based on the temperature t3 detected by the thermistor 61. Adjust the air volume of 33. As a result, the cooling device 30 can keep the temperature of the endothermic unit 32Ba always in the vicinity of the target temperature T3, and can more appropriately cool the laser light source unit (laser array chip 21) and the condenser lens 23.

Since the laser light emitting device 10H of the fourth embodiment basically has the same configuration as the laser light emitting device 10B of FIG. 6, basically the same effect as the example of FIG. 6 can be obtained.

In addition, the laser light emitting device 10H adjusts the air volume of the blower fan 33 so that the endothermic unit 32Ba reaches the target temperature T3, so that the laser light source unit (laser array chip 21) and the condenser lens 23 are cooled more appropriately. can.

Therefore, in the laser light emitting device 10H of the fourth embodiment of the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the fourth embodiment, the thermistor 61 is provided only in the endothermic portion 32Ba, but the thermistor 63 may be provided only in the lens holding member 14 as in the example of FIG. The thermistor 63 may be provided, and the configuration is not limited to that of the fourth embodiment.

Next, the laser light emitting device 10I of the fifth embodiment, which is one embodiment of the present disclosure, will be described with reference to FIGS. 16 and 17. The laser light emitting device 10I is an example in which the thermistor 63 and the temperature control device 62I are provided in the laser light emitting device 10C shown in FIG. 7. Since the laser light emitting device 10I has the same basic concept, configuration, and effect as the laser light emitting device 10C of FIG. 7, the same reference numerals are given to the parts having the same configuration, and detailed description thereof will be omitted.

In the laser light emitting device 10I of the fifth embodiment, the accuracy of cooling the laser light source unit (laser array chip 21) and the condensing lens 23 by the cooling device 30 is the same as that of the laser light emitting device 10E of the second embodiment. It is higher than the laser light emitting device 10C of. First, as shown in FIG. 16, the laser light emitting device 10I is provided with a liquid storage tank 64, a pump 65, and a heat exchanger 66 in a refrigerant passage 32C of a liquid-cooled heat sink 32C. In the refrigerant passage 32Ce, the pump 65 is driven to send the cooling water stored in the liquid storage tank 64 to the heat exchanger 66, and the cooling water cooled by the heat exchanger 66 is supplied to the heat sink 32C. .. Then, the cooling water that has been heated by heat exchange with the heat sink 32C is stored in the liquid storage tank 64. Therefore, in the laser light emitting device 10I, the refrigerant passage 32Ce, the liquid storage tank 64, the pump 65, and the heat exchanger 66 all function as heat dissipation function units of the cooling device 30.

The laser light emitting device 10I has the thermistor 63 and the temperature control device 62I similar to those in the second embodiment. The thermistor 63 is an example of a temperature detection unit that detects the temperature t2 of the lens holding member 14 in the laser output mechanism, and sends the temperature t2 detected via the detection line 63a to the temperature control device 62I. Along with this, the exterior member 28 is provided with a detection opening 28e through which the detection line 63a passes.

The temperature control device 62I controls the amount of heat exchange (cooling force) in the heat exchanger 66 in the heat dissipation function unit of the cooling device 30, and is connected to the power line 66a of the heat exchanger 66 and the thermistor 63. Detection line 63a is connected. The temperature control device 62I adjusts the amount of heat exchange in the heat exchanger 66 so that the lens holding member 14 reaches the preset target temperature T2 based on the temperature t2 detected by the thermistor 63. That is, the temperature control device 62 increases the amount of heat exchange in the heat exchanger 66 to lower the temperature of the refrigerant when the temperature t2 is higher than the target temperature T2, and lowers the temperature of the refrigerant when the temperature t2 is lower than the target temperature T2. Reduce the amount of heat exchange in and raise the temperature of the refrigerant. At this time, the amount of heat exchange in the heat exchanger 66 may be adjusted according to the difference between the temperature t2 and the target temperature T2, or may be adjusted to a predetermined amount of heat exchange regardless of the difference.

Next, in the laser light emitting device 10I, an example of a temperature control process in which the temperature control device 62I controls the amount of heat exchange in the heat exchanger 66 for adjusting the cooling temperature will be described with reference to FIG. The temperature control process is basically the same as the temperature control process shown in the flowchart of FIG. 10, and is executed by the temperature control device 62I based on the program stored in the built-in memory. Hereinafter, each step (each step) of the flowchart of FIG. 17 will be described.

Step S41 acquires the temperature t2 from the thermistor 63 and proceeds to step S42.

Step S42 determines whether or not the temperature t2 is the same as the target temperature T2. If YES, the process proceeds to step S43, and if NO, the process proceeds to step S44.

In step S43, the heat exchange amount in the heat exchanger 66 is maintained, and the process proceeds to step S47.

Step S44 determines whether or not the temperature t2 is higher than the target temperature T2. If YES, the process proceeds to step S45, and if NO, the process proceeds to step S46.

In step S45, the amount of heat exchanged by the heat exchanger 66 is increased, and the process proceeds to step S47.

In step S46, the amount of heat exchanged by the heat exchanger 66 is reduced, and the process proceeds to step S47.

In step S47, it is determined whether or not the laser light emitting device 10I has been stopped. If YES, this temperature control process is terminated, and if NO, the process proceeds to step S48.

Step S48 determines whether or not the sampling interval has reached Δt. If YES, the process returns to step S41, and if NO, step S48 is repeated.

When the laser light emitting device 10I is driven, the cooling device 30 starts cooling the laser light source unit (laser array chip 21). At that time, the temperature control device 62I performs the temperature control process shown in the flowchart of FIG. 17 so that the lens holding member 14 becomes the target temperature T2 based on the temperature t2 detected by the thermistor 63. Adjust the amount of heat exchange in. As a result, the cooling device 30 can keep the temperature of the lens holding member 14 in the vicinity of the target temperature T2, and can more appropriately cool the laser light source unit (laser array chip 21) and the condenser lens 23.

Since the laser light emitting device 10I of the fifth embodiment basically has the same configuration as the laser light emitting device 10C of FIG. 7, basically the same effect as the example of FIG. 7 can be obtained.

In addition, the laser light emitting device 10I adjusts the amount of heat exchange in the heat exchanger 66 so that the lens holding member 14 reaches the target temperature T2, so that the laser light source unit (laser array chip 21) and the condenser lens 23 Can be cooled more appropriately.

Therefore, in the laser light emitting device 10I of the fifth embodiment of the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the fifth embodiment, the thermistor 63 is provided only on the lens holding member 14, but the thermistor 61 may be provided only on the heat diffusion plate 15 as in the second embodiment, and the thermistor 61 may be provided only on the heat diffusion plate 15 as in the third embodiment. The thermistor 63 may be provided, and the configuration is not limited to that of the fifth embodiment.

Next, the laser light emitting device 10J of the sixth embodiment, which is one embodiment of the present disclosure, will be described with reference to FIGS. 18 and 19. The laser light emitting device 10J is an example in which the pump 65 is controlled in place of the heat exchanger 66 in the laser light emitting device 10I shown in FIG. 16 of the fifth embodiment. Since the laser light emitting device 10J has the same basic concept, configuration, and effect as the laser light emitting device 10I of the fifth embodiment, the same reference numerals are given to the parts having the same configuration, and detailed description thereof will be omitted.

Similar to the laser light emitting device 10I of the fifth embodiment, the laser light emitting device 10J of the sixth embodiment determines the accuracy of cooling of the laser light source unit (laser array chip 21) and the condenser lens 23 by the cooling device 30 with respect to the laser of FIG. It is higher than the light emitting device 10C. The temperature control device 62J controls the output (amount (flow rate) of sending out cooling water) of the pump 65 in the heat dissipation function unit of the cooling device 30, and the power line 65a of the pump 65 is connected and the thermistor. The detection line 63a of 63 is connected. The temperature control device 62J adjusts the output of the pump 65 so that the lens holding member 14 reaches the target temperature T2 based on the temperature t2 detected by the thermistor 63. That is, the temperature control device 62 increases the output of the pump 65 when the temperature t2 is higher than the target temperature T2 to increase the flow rate of the refrigerant, and decreases the output of the pump 65 when the temperature t2 is lower than the target temperature T2. Reduce the flow rate of the refrigerant. At this time, the output of the pump 65 may be adjusted according to the difference between the temperature t2 and the target temperature T2, or may be adjusted to a predetermined output regardless of the difference.

Next, in the laser light emitting device 10J, an example of a temperature control process in which the temperature control device 62J controls the output of the pump 65 for adjusting the cooling temperature will be described with reference to FIG. The temperature control process is basically the same as the temperature control process shown in the flowchart of FIG. 10, and is executed by the temperature control device 62J based on the program stored in the built-in memory. Hereinafter, each step (each step) of the flowchart of FIG. 19 will be described.

Step S51 acquires the temperature t2 from the thermistor 63 and proceeds to step S52.

Step S52 determines whether or not the temperature t2 is the same as the target temperature T2. If YES, the process proceeds to step S53, and if NO, the process proceeds to step S54.

Step S53 maintains the output of the pump 65 and proceeds to step S57.

Step S54 determines whether or not the temperature t2 is higher than the target temperature T2. If YES, the process proceeds to step S55, and if NO, the process proceeds to step S56.

In step S55, the output of the pump 65 is increased, and the process proceeds to step S57.

In step S56, the output of the pump 65 is reduced, and the process proceeds to step S57.

In step S57, it is determined whether or not the laser light emitting device 10J has been stopped. If YES, this temperature control process is terminated, and if NO, the process proceeds to step S58.

Step S58 determines whether or not the sampling interval has reached Δt. If YES, the process returns to step S51, and if NO, step S58 is repeated.

When the laser light emitting device 10J is driven, the cooling device 30 starts cooling the laser light source unit (laser array chip 21). At that time, the temperature control device 62J performs the temperature control process shown in the flowchart of FIG. 19 to output the pump 65 so that the lens holding member 14 reaches the target temperature T2 based on the temperature t2 detected by the thermistor 63. To adjust. As a result, the cooling device 30 can keep the temperature of the lens holding member 14 in the vicinity of the target temperature T2, and can more appropriately cool the laser light source unit (laser array chip 21) and the condenser lens 23.

Since the laser light emitting device 10J of the sixth embodiment basically has the same configuration as the laser light emitting device 10I of the fifth embodiment, basically the same effect as that of the fifth embodiment can be obtained.

In addition, the laser light emitting device 10J adjusts the output of the pump 65 so that the lens holding member 14 reaches the target temperature T2, so that the laser light source unit (laser array chip 21) and the condenser lens 23 are cooled more appropriately. can.

Therefore, in the laser light emitting device 10J of the sixth embodiment of the laser light emitting device according to the present disclosure, even if the high intensity laser light is focused by the condenser lens 23, the temperature rise of the condenser lens 23 can be suppressed.

In the sixth embodiment, the thermistor 63 is provided only on the lens holding member 14, but the thermistor 61 may be provided only on the heat diffusion plate 15 as in the second embodiment, and the thermistor 61 may be provided only on the heat diffusion plate 15 as in the third embodiment. The thermistor 63 may be provided, and the configuration is not limited to that of the sixth embodiment.

The laser light emitting device of the present disclosure has been described based on each embodiment and the examples shown in FIGS. 5 to 8 and 11, but the specific configuration is described in each embodiment and FIGS. 5 to 8 and 11. The design is not limited to the example shown, and design changes and additions are permitted as long as the gist of the present invention is not deviated.

10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I Laser light emitting device (as an example of laser light emitting device) 14 Lens holding member (as an example of holding member) 15 (Endothermic function part and heat Heat diffusion plate (as an example of diffuser) 16 Lens holding hole 16c Inner surface 21 (As an example of laser light source) Laser array chip 23 Condensing lens 23c Outer surface 23b Flat surface 23d Anti-reflection treatment film 27 (Heat transfer promotion member) (As an example) Heat transfer grease 28 Exterior member 28c Cooling opening 30 Cooling device 31 (Consists of a part of the heat dissipation function part as an example) Pelche element 32 (As an example of the heat dissipation member) Heat sink 32a (As an example of the heat absorption function part) (As an example) Endothermic part 32b Heat dissipation part 32Ce (Consists of a part of the heat dissipation function part as an example) Coolant passage 33 (Consists of a part of the heat dissipation function part as an example) Blower fan 40 Engine ignition plug system

Japanese Unexamined Patent Publication No. 2014-192166

Claims (14)

A laser light source unit that emits laser light and
A condensing lens that collects the laser light emitted from the laser light source unit at a predetermined position,
A holding member that holds the condenser lens while in surface contact with the condenser lens,
A cooling device addressed to the laser light source unit to cool the laser light source unit, and
It is provided with an exterior member having a lower thermal conductivity than the holding member and surrounding the outside of the holding member.
The holding member is a laser light emitting device having a higher thermal conductivity than the condensing lens and being in surface contact with the cooling device. The cooling device includes a heat dissipation function unit whose amount of heat radiation can be adjusted, and at least one temperature detection unit that detects the temperature of a laser output mechanism having the laser light source unit, the condenser lens, and the holding member.
The laser light emitting device according to claim 1, wherein the heat radiation function unit adjusts the amount of heat radiation according to the temperature detected by the temperature detection unit. The laser light emitting device according to claim 2, wherein the heat dissipation function unit has a thermoelectric element, and the temperature of the cooling surface of the thermoelectric element is adjusted according to the temperature detected by the temperature detection unit. The laser light emitting device according to claim 2, wherein the heat radiating function unit has a blowing mechanism, and the air volume of the blowing mechanism is adjusted according to the temperature detected by the temperature detecting unit. The laser light emitting device according to claim 2, wherein the heat dissipation function unit has a refrigerant passage through which the refrigerant passes, and the temperature or flow rate of the refrigerant is adjusted according to the temperature detected by the temperature detection unit. .. The laser light emitting device according to any one of claims 1 to 5, wherein the condensing lens is a plano-convex lens, and a flat surface is brought into surface contact with the holding member. The holding member is provided with a lens holding hole for receiving the condenser lens.
The condenser lens has an outer surface that makes surface contact with the inner surface of the lens holding hole.
The laser light emitting device according to any one of claims 1 to 6, wherein the inner surface is larger than the outer surface. The laser light emitting device according to any one of claims 1 to 7, wherein the holding member has a heat transfer promoting member interposed at a portion that comes into surface contact with the condensing lens and the cooling device. The laser light emitting device according to any one of claims 1 to 8, wherein the condensing lens is provided with an antireflection processing film on the surface thereof. 9. The exterior member has a cooling opening that exposes a part of the cooling device that is in surface contact with the holding member, and the cooling opening contacts the endothermic function portion of the cooling device. The laser light emitting device according to. The laser light emitting device according to any one of claims 1 to 10, wherein the laser light source unit has a laser array chip in which a plurality of surface emitting lasers are arranged. The cooling device has a heat radiating member that dissipates heat absorbed by the heat absorbing portion in the heat radiating portion so as to form at least a part of the heat radiating function portion.
The holding member is a laser light emitting device according to any one of claims 1 to 11, characterized that you face in contact with the heat absorbing portion. The cooling device includes a heat radiating member that dissipates heat absorbed by the heat absorbing portion in order to form at least a part of the heat radiating function portion, and a heat conduction member equal to or higher than the holding member so as to form at least a part of the heat absorbing function portion. It has a heat diffusion member having a rate, which is addressed to the endothermic portion and is provided with the laser light source portion .
The laser light emitting device according to any one of claims 1 to 12, wherein the holding member comes into surface contact with the heat diffusion member. The laser light emitting device according to any one of claims 1 to 13.
Engine ignition plug system characterized Rukoto provided a spark plug for igniting the internal combustion engine, the using laser light output from the laser light emitting device.

Images