JP2016072610A - Laser apparatus, ignition apparatus and internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser apparatus capable of stably obtaining a desired laser characteristic.SOLUTION: A laser apparatus 200 includes: a surface emitting laser 201; a first light converging optical system 203; an optical fiber 204; a second light converging optical system 205 including a plurality of optical elements and a plurality of spacer members (207a-207d); and a laser resonator 206. The plurality of spacer members (207a-207d) are used for adjusting positions of the plurality of optical elements of the second light converging optical system 205 and a position of the laser resonator 206 in a Z-axis direction. Consequently, "a beam waist diameter", "an incident angle" and "a distance from a first surface up to a focal point" of light made incident on the laser resonator 206 can be individually and highly accurately adjusted.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a laser device, an ignition device, and an internal combustion engine, and more particularly to a laser device having a laser resonator, an ignition device having the laser device, and an internal combustion engine including the ignition device.

  A laser device using a laser crystal that oscillates by optical excitation is expected to be applied to various fields such as an ignition device, a laser processing machine, and a medical device.

  For example, Patent Literature 1 discloses a laser ignition device including a laser device and a pump light source having a plurality of surface emitting lasers.

  However, it has been difficult for the conventional laser apparatus to stably obtain desired laser characteristics.

  The present invention provides a light source, a light transmission member that transmits light emitted from the light source, a plurality of optical elements disposed on an optical path of light via the light transmission member, and the plurality of optical elements. The laser device includes a laser resonator to which the received light is input and an adjustment mechanism for adjusting the position of at least one of the plurality of optical elements.

  According to the laser device of the present invention, desired laser characteristics can be stably obtained.

It is a figure for demonstrating the outline of the engine 300 which concerns on one Embodiment of this invention. It is a figure for demonstrating the ignition device. 6 is a diagram for explaining a laser resonator 206. FIG. It is a figure for demonstrating the incident angle of the light which injects into the laser resonator 206, the beam waist diameter, and the distance from a 1st surface to a focus. It is a figure for demonstrating the 2nd condensing optical system. It is a figure for demonstrating a position adjustment mechanism. FIG. 7A and FIG. 7B are diagrams for explaining the spacer member. FIG. 8A and FIG. 8B are diagrams for explaining a first adjustment method when the first lens 205a is moved to the −Z side from the reference configuration. FIG. 9A and FIG. 9B are diagrams for explaining a second adjustment method in the case where the first lens 205a is moved to the −Z side from the reference configuration. FIGS. 10A and 10B are views for explaining a first adjustment method in the case where the first lens 205a is moved to the + Z side from the reference configuration. FIG. 11A and FIG. 11B are diagrams for explaining a second adjustment method when the first lens 205a is moved to the + Z side from the reference configuration. FIG. 12A and FIG. 12B are diagrams for explaining a first adjustment method in the case where the second lens 205b is moved to the −Z side from the reference configuration. FIGS. 13A and 13B are diagrams for describing a second adjustment method in the case where the second lens 205b is moved to the −Z side from the reference configuration. FIGS. 14A and 14B are diagrams for explaining a first adjustment method in the case where the second lens 205b is moved to the + Z side from the reference configuration. FIG. 15A and FIG. 15B are diagrams for explaining a second adjustment method when the second lens 205b is moved to the + Z side from the reference configuration. FIGS. 16A and 16B are diagrams for explaining a first adjustment method in the case where the laser resonator 206 is moved to the −Z side from the reference configuration. FIGS. 17A and 17B are diagrams for explaining a second adjustment method in the case where the laser resonator 206 is moved to the −Z side from the reference configuration. 18A and 18B are diagrams for explaining an adjustment method 1 in the case where the laser resonator 206 is moved to the + Z side from the reference configuration. FIGS. 19A and 19B are diagrams for explaining the adjustment method 2 in the case where the laser resonator 206 is moved to the + Z side from the reference configuration. It is a figure for demonstrating the modification 1 of a laser apparatus. It is a figure for demonstrating the modification 2 of a laser apparatus.

"Overview"
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows a main part of an engine 300 as an internal combustion engine according to an embodiment.

  The engine 300 includes an ignition device 301, a fuel ejection mechanism 302, an exhaust mechanism 303, a combustion chamber 304, a piston 305, and the like.

The operation of engine 300 will be briefly described.
(1) The fuel ejection mechanism 302 ejects a combustible mixture of fuel and air into the combustion chamber 304 (intake).
(2) The piston 305 rises and compresses the combustible air-fuel mixture (compression).
(3) The ignition device 301 emits laser light into the combustion chamber 304. Thereby, the fuel is ignited (ignition).
(4) Combustion gas is generated and the piston 305 descends (combustion).
(5) The exhaust mechanism 303 exhausts the combustion gas to the outside of the combustion chamber 304 (exhaust).

  Thus, a series of processes consisting of intake, compression, ignition, combustion, and exhaust are repeated. Then, the piston 305 moves in response to a change in the volume of the gas in the combustion chamber 304 to generate kinetic energy. For example, natural gas or gasoline is used as the fuel.

  Engine 300 performs the above operation based on an instruction of an engine control device that is provided outside engine 300 and is electrically connected to engine 300.

  As shown in FIG. 2 as an example, the ignition device 301 includes a laser device 200, an emission optical system 210, a protection member 212, and the like.

  The emission optical system 210 condenses the light emitted from the laser device 200. Thereby, a high energy density can be obtained at the condensing point.

  The protection member 212 is a transparent window provided facing the combustion chamber 304. Here, as an example, sapphire glass is used as the material of the protection member 212.

  The laser device 200 includes a surface emitting laser array 201, a first condensing optical system 203, an optical fiber 204, a second condensing optical system 205, and a laser resonator 206. In the present specification, description will be made using the XYZ three-dimensional orthogonal coordinate system and assuming that the light emission direction from the surface emitting laser array 201 is the + Z direction.

  The surface emitting laser array 201 is an excitation light source and has a plurality of light emitting units. Each of the light emitting units is a vertical cavity surface emitting laser (VCSEL: Vertical Cavity Surface Emitting Laser).

  The surface-emitting laser array is a light source that is advantageous for exciting a Q-switched laser whose characteristics change greatly due to a shift in excitation wavelength because the wavelength shift of emitted light due to temperature is very small. Therefore, when a surface emitting laser array is used as an excitation light source, there is an advantage that environmental temperature control can be simplified.

  The first condensing optical system 203 condenses the light emitted from the surface emitting laser array 201.

  The optical fiber 204 is arranged so that the center of the end face on the −Z side of the core is located at a position where the light is collected by the first condensing optical system 203.

  By providing the optical fiber 204, the surface emitting laser array 201 can be placed at a position away from the laser resonator 206. Thereby, the freedom degree of arrangement design can be increased. Further, when the laser device 200 is used as an ignition device, the surface emitting laser array 201 can be moved away from the heat source, so that the range of methods for cooling the engine 300 can be increased.

  The light incident on the optical fiber 204 propagates through the core and is emitted from the + Z side end face of the core.

  The second condensing optical system 205 is disposed on the optical path of the light emitted from the optical fiber 204 and condenses the light. The light condensed by the second condensing optical system 205 enters the laser resonator 206.

  The laser resonator 206 is a Q-switched laser and includes a laser medium 206a and a saturable absorber 206b as shown in FIG. 3 as an example.

  The laser medium 206a is a rectangular parallelepiped Nd: YAG crystal having a resonator length of 8 mm. The saturable absorber 206b is a rectangular parallelepiped Cr: YAG crystal having a length of 2 mm.

  Here, the Nd: YAG crystal and the Cr: YAG crystal are joined to form a so-called composite crystal. Both the Nd: YAG crystal and the Cr: YAG crystal are ceramics.

  The light from the second condensing optical system 205 is incident on the laser medium 206a. That is, the laser medium 206a is excited by the light from the second condensing optical system 205. Note that the wavelength of light emitted from the surface emitting laser array 201 is desirably a wavelength of 808 nm, which has the highest absorption efficiency in the YAG crystal. The saturable absorber 206b operates as a Q switch.

  The surface on the incident side (−Z side) of the laser medium 206a and the surface on the exit side (+ Z side) of the saturable absorber 206b are subjected to an optical polishing process and serve as a mirror. Hereinafter, for convenience, the incident-side surface of the laser medium 206a is also referred to as a “first surface”, and the exit-side surface of the saturable absorber 206b is also referred to as a “second surface” (see FIG. 3).

  The first surface and the second surface are coated with a dielectric film corresponding to the wavelength of light emitted from the surface emitting laser array 201 and the wavelength of light emitted from the laser resonator 206. .

  Specifically, the first surface is coated with a sufficiently high transmittance for light having a wavelength of 808 nm and a sufficiently high reflectance for light having a wavelength of 1064 nm. In addition, the second surface is coated with a reflectance that is selected so that a desired threshold is obtained for light having a wavelength of 1064 nm.

  As a result, the light resonates and is amplified in the laser resonator 206. Here, the resonator length of the laser resonator 206 is 10 (= 8 + 2) mm.

  Returning to FIG. 2, the driving device 220 drives the surface emitting laser array 201 based on an instruction from the engine control device 222. That is, drive device 220 drives surface emitting laser array 201 so that light is emitted from ignition device 301 at the timing of ignition in the operation of engine 300. The plurality of light emitting units in the surface emitting laser array 201 are turned on and off simultaneously.

  In the above embodiment, when it is not necessary to place the surface emitting laser array 201 at a position away from the laser resonator 206, the optical fiber 204 may not be provided.

  Further, each of the first condensing optical system 203 and the emission optical system 210 may be composed of a single lens or a plurality of lenses.

  Here, the case of an engine (piston engine) in which a piston is moved by combustion gas as an internal combustion engine has been described. However, the present invention is not limited to this. For example, a rotary engine, a gas turbine engine, or a jet engine may be used. In short, what is necessary is just to burn the fuel and generate the combustion gas.

  In addition, the ignition device 301 may be used for cogeneration, which is a system that uses exhaust heat to extract power, heat, and cold to improve energy efficiency comprehensively.

  Although the case where the ignition device 301 is used in an internal combustion engine has been described here, the present invention is not limited to this.

  Although the case where the laser device 200 is used in an ignition device has been described here, the present invention is not limited to this. For example, it can be used for a laser processing machine, a laser peening apparatus, a terahertz generator, and the like.

"Details"
The so-called incident light characteristics such as “beam waist diameter” and “incident angle” of light incident on the laser resonator 206 and “distance from the first surface to the focal point” (see FIG. 4) are the Q-switched laser characteristics. A big influence. For example, when the incident light characteristic changes due to an assembly error, the Q-switch laser characteristic changes.

  The plurality of light emitting portions in the surface emitting laser 201 are arranged in a region having a diameter of 8.9 mm. When light is emitted from the surface emitting laser 201, the plurality of light emitting units emit light simultaneously.

  Thus, since the surface emitting laser 201 has a plurality of light emitting units, the light output can be increased. Here, the optical output of the surface emitting laser 201 is about 200 W.

  In the present embodiment, the second condensing optical system 205 includes a first lens 205a, a second lens 205b, and a plurality of spacer members (207a to 207d) (see FIG. 5). The second condensing optical system 205 may have three or more lenses.

  The first lens 205a is a collimating lens, and makes light emitted from the optical fiber 204 substantially parallel light. Here, a collimating lens (manufactured by Thorlabs, model number: C240TME-B) having a focal length of 8 mm is used as the first lens 205a.

  The second lens 205b is a condensing lens, and condenses the light that has been made substantially parallel by the first lens 205a. Here, a condensing lens having a focal length of 6.24 mm (manufactured by Thorlabs, model number: C110TME-B) is used as the second lens 205b.

  In addition, you may use things other than the above as the 1st lens 205a and the 2nd lens 205b.

  In the present embodiment, the incident light characteristics can be adjusted by adjusting the positions of the first lens 205a, the second lens 205b, and the laser resonator 206 in the Z-axis direction.

  For example, when adjusting the “distance from the first surface to the focal point”, the position of at least one of the second lens 205b and the laser resonator 206 in the Z-axis direction is adjusted.

  When adjusting the “beam waist diameter”, the position of at least one of the first lens 205a and the second lens 205b in the Z-axis direction is adjusted.

  When adjusting the “incident angle”, the position of at least one of the first lens 205a and the second lens 205b in the Z-axis direction is adjusted.

  In the present embodiment, the position adjustment of the first lens 205a is performed by at least one of the spacer member 207a and the spacer member 207b.

  The position adjustment of the second lens 205b is performed by at least one of the spacer member 207b and the spacer member 207c.

  The position adjustment of the laser resonator 206 is performed by at least one of the spacer member 207c and the spacer member 207d.

  Here, as an example, as shown in FIG. 6, the first lens 205 a is held by the first lens holder 226, and the second lens 205 b is held by the second lens holder 223. The laser resonator 206 is held by the crystal holder 224, and the emission optical system 210 is held by the third lens holder 225. The optical fiber 204 is held by the fiber holder 221.

  Each holder has a male screw formed on the outer periphery. The first lens holder 226, the second lens holder 223, and the crystal holder 224 are housed inside the oscillation housing. A female screw corresponding to the male screw of each holder is formed inside the oscillation housing. The fiber holder 221 is screwed into the oscillation casing from the −Z side end of the oscillation casing, and the third lens holder 225 is screwed into the oscillation casing from the + Z side end of the oscillation casing. In this case, each holder can be moved in the Z-axis direction by rotating each holder.

  That is, the position of the first lens 205a in the Z-axis direction can be adjusted by rotating the first lens holder 226. Further, the position of the second lens 205b in the Z-axis direction can be adjusted by rotating the second lens holder 223. Further, the position of the laser resonator 206 in the Z-axis direction can be adjusted by rotating the crystal holder 224.

  As shown in FIGS. 7A and 7B as an example, each spacer member is a ring-shaped plate member having an opening at the center so that light can pass therethrough. Note that FIG. 7B is a cross-sectional view taken along the line AA in FIG.

  Here, a stainless steel (SUS430) plate member is used as each spacer member. In the basic configuration, the spacer member 207a has a plate thickness of 1.32 mm, the spacer member 207b has a plate thickness of 2.0 mm, the spacer member 207c has a plate thickness of 1.4 mm, and the spacer member 207d has a plate thickness. The thickness is 1.0 mm. Further, here, a plurality of plate members having different plate thicknesses are prepared.

(1) When the first lens 205a is moved to the −Z side with respect to the reference configuration In this case, as shown in FIGS. 8A and 8B, the spacer member 207a is set as the reference configuration. The thinner plate member is replaced, and the spacer member 207b is replaced with a thicker plate member than the reference configuration.

  Specifically, for example, when the moving amount is 0.5 mm, the spacer member 207a is replaced with a plate member having a plate thickness of 0.82 mm, and the spacer member 207b is replaced with a 2.5 mm plate member.

  In this case, as shown in FIG. 9A and FIG. 9B as an example, the spacer member 207a is replaced with a plate member thinner than the reference configuration, and the first lens holder 226 and the reference configuration spacer are replaced. The spacer member 207b ′ may be inserted into the gap with the member 207b.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207a is replaced with a plate member having a plate thickness of 0.82 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207b '.

(2) When moving the first lens 205a to the + Z side with respect to the reference configuration In this case, as shown in FIG. 10A and FIG. 10B as an example, the spacer member 207a is moved from the reference configuration. In addition, the spacer member 207b is replaced with a plate member thinner than the reference configuration.

  Specifically, for example, when the moving amount is 0.5 mm, the spacer member 207a is replaced with a plate member having a plate thickness of 1.82 mm, and the spacer member 207b is replaced with a 1.5 mm plate member.

  In this case, as an example, as shown in FIGS. 11A and 11B, the spacer member 207b is replaced with a plate member thinner than the reference configuration, and the first lens holder 226 and the reference configuration spacer are replaced. The spacer member 207a ′ may be inserted into the gap with the member 207a.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207b is replaced with a plate member having a plate thickness of 1.5 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207a '.

(3) When the second lens 205b is moved to the −Z side with respect to the reference configuration In this case, as shown in FIGS. 12A and 12B, the spacer member 207b is set as the reference configuration. The thinner plate member is replaced, and the spacer member 207c is replaced with a thicker plate member than the reference configuration.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207b is replaced with a plate member having a plate thickness of 1.5 mm, and the spacer member 207c is replaced with a plate member having a thickness of 1.9 mm.

  In this case, as shown in FIGS. 13A and 13B as an example, the spacer member 207b is replaced with a plate member thinner than the reference configuration, and the second lens holder 223 and the reference configuration spacer are replaced. A spacer member 207c ′ may be inserted into the gap with the member 207c.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207b is replaced with a plate member having a plate thickness of 1.5 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207c '.

(4) When moving the second lens 205b to the + Z side with respect to the reference configuration In this case, as shown in FIG. 14A and FIG. 14B as an example, the spacer member 207c is moved from the reference configuration. In addition, the spacer member 207b is replaced with a thicker plate member than the reference structure.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207c is replaced with a plate member having a plate thickness of 0.9 mm, and the spacer member 207b is replaced with a plate member having a thickness of 2.5 mm.

  In this case, as an example, as shown in FIGS. 15A and 15B, the spacer member 207c is replaced with a plate member thinner than the reference configuration, and the second lens holder 223 and the reference configuration spacer are replaced. The spacer member 207b ′ may be inserted into the gap with the member 207b.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207 c is replaced with a plate member having a plate thickness of 0.9 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207 b ′.

(5) When moving the laser resonator 206 to the −Z side with respect to the reference configuration In this case, as shown in FIGS. 16A and 16B, the spacer member 207c is set as the reference configuration. The spacer member 207d is replaced with a plate member that is thicker than the reference configuration.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207c is replaced with a plate member having a plate thickness of 0.9 mm, and the spacer member 207d is replaced with a plate member having a thickness of 1.5 mm.

  In this case, as shown in FIGS. 17A and 17B as an example, the spacer member 207c is replaced with a plate member thinner than the reference configuration, and the crystal holder 224 and the reference configuration spacer member 207d are also replaced. A spacer member 207d ′ may be inserted into the gap.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207c is replaced with a plate member having a plate thickness of 0.9 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207d '.

(6) When moving the laser resonator 206 to the + Z side with respect to the reference configuration In this case, as shown in FIG. 18 (A) and FIG. 18 (B) as an example, the spacer member 207d is moved from the reference configuration. In addition, the spacer member 207c is replaced with a thicker plate member than the reference configuration.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207d is replaced with a plate member having a plate thickness of 0.5 mm, and the spacer member 207c is replaced with a plate member having a thickness of 1.9 mm.

  In this case, as shown in FIG. 19A and FIG. 19B as an example, the spacer member 207d is replaced with a plate member thinner than the reference configuration, and the crystal holder 224 and the reference configuration spacer member 207c are also replaced. The spacer member 207c ′ may be inserted into the gap.

  Specifically, for example, when the movement amount is 0.5 mm, the spacer member 207d is replaced with a plate member having a plate thickness of 0.5 mm, and a plate member having a plate thickness of 0.5 mm is used as the spacer member 207c '.

  In the present embodiment, the first lens 205a, the second lens 205b, and the laser are set so that the operator can reach the target value of the Q-switched laser output, which is a characteristic of the light emitted from the laser resonator 206, and the number of pulses. The position of the resonator 206 is adjusted. Here, the target value of the number of pulses is set to four every 500 μs.

  By the position adjustment, the distance between the + Z side end face of the optical fiber 204 and the first lens 205a can be adjusted within a range of about 3 mm. The distance between the first lens 205a and the second lens 205b can be adjusted within a range of about 10 mm. The distance between the second lens 205b and the laser resonator 206 can be adjusted within a range of about 5 mm. Further, the distance between the laser resonator 206 and the emission optical system 210 can be adjusted within a range of about 50 mm. In addition, these adjustable ranges are examples, and are not limited to these.

  If the position of the second lens 205b can be adjusted, the “distance from the first surface to the focal point” can be adjusted without adjusting the positions of the first lens 205a and the laser resonator 206. .

  The ignition device 301 using the laser device 200 has higher energy than an ordinary ignition device, for example, a spark plug, and the ignition position can be arbitrarily changed. Therefore, improvement in engine efficiency can be expected.

  As is clear from the above description, according to the laser apparatus 200 according to the present embodiment, the plurality of optical elements in the present invention are configured by the second condensing optical system 205, and at least one of the spacer members 207a to 207c is used. An adjustment mechanism for adjusting the position of the optical element is configured. Further, the spacer member 207c and the spacer member 207d constitute an adjustment mechanism for adjusting the position of the laser resonator in the present invention.

  As described above, the laser apparatus 200 according to this embodiment includes the surface emitting laser 201, the first condensing optical system 203, the optical fiber 204, the plurality of optical elements, and the plurality of spacer members (207a to 207d). Two condensing optical systems 205 and a laser resonator 206 are provided.

  The surface emitting laser 201 has a plurality of light emitting portions. The light emitted from the surface emitting laser 201 is condensed by the first condensing optical system 203, propagates through the optical fiber 204, is condensed by the second condensing optical system 205, and enters the laser resonator 206.

  The laser resonator 206 is a composite crystal of a laser medium 206a and a saturable absorber 206b. This composite crystal has the same characteristics as a single crystal because the boundary between the laser medium 206a and the saturable absorber 206b is not separated, and is advantageous mechanically and optically.

  The plurality of spacer members (207a to 207d) are used to adjust the positions of the plurality of optical elements of the second condensing optical system 205 and the laser resonator 206 in the Z-axis direction.

  That is, in the laser apparatus 200, a plurality of optical elements are provided between the optical fiber 204 and the laser resonator 206, and adjustment for adjusting the positions of the plurality of optical elements and the laser resonator 206 in the Z-axis direction is performed. A mechanism is provided.

  In this case, the “beam waist diameter” and “incident angle” of the light incident on the laser resonator 206 and the “distance from the first surface to the focal point” can be individually adjusted with high accuracy. Therefore, even if there is an assembly error, desired Q-switch laser characteristics can be stably obtained.

  If the second condensing optical system 205 is composed of a single lens, the “beam waist diameter” of the light incident on the laser resonator 206 even if the position of the lens in the Z-axis direction is adjusted. It is difficult to individually adjust the “incident angle” and “distance from the first surface to the focal point” with high accuracy.

  And since the ignition device 301 which concerns on this embodiment has the laser apparatus 200, as a result, stable ignition can be performed. In addition, by adjusting the focal length of the emission optical system 210, the condensing position in the Z-axis direction can be adjusted.

  Furthermore, since the engine 300 according to the present embodiment includes the ignition device 301, the operation can be stabilized as a result.

  In addition, although the said embodiment demonstrated the case where the material of the spacer member was stainless steel, it is not limited to this.

  Moreover, although the said embodiment demonstrated the case where the external shape of a spacer member was circular shape, it is not limited to this. For example, the outer shape of the spacer member may be rectangular or elliptical.

  Further, in the above embodiment, if the position adjustment of the laser resonator 206 is unnecessary, the spacer member 207d may be omitted as in the laser device 400 shown in FIG. 20 as an example.

  Moreover, although the said embodiment demonstrated the case where the position adjustment of the 1st lens 205a, the 2nd lens 205b, and the laser resonator 206 was performed using a spacer member, it is not limited to this. For example, a fixing screw may be used (see FIG. 21).

  Each fixing screw penetrates the oscillating housing along a direction orthogonal to the Z axis, and its tip faces each holder. Therefore, when the fixing screw is tightened, the holder is fixed to the oscillation housing, and when the fixing screw is loosened, the holder is released from the oscillation housing. The fixing screw is loosened when adjusting the position of the corresponding holder, and is tightened when the adjustment is completed.

  Moreover, although the said embodiment demonstrated the case where the position adjustment using a spacer member was used only for the position adjustment regarding a Z-axis direction, it is not limited to this, For example, an X-axis direction or a Y-axis direction May also be used for position adjustment.

  DESCRIPTION OF SYMBOLS 200 ... Laser apparatus, 201 ... Surface emitting laser, 203 ... 1st condensing optical system, 204 ... Optical fiber, 205 ... 2nd condensing optical system, 205a ... 1st lens (one of several optical elements), 205b ... Second lens (one of a plurality of optical elements), 206 ... Laser resonator, 206a ... Laser medium, 206b ... Saturable absorber, 207a to 207d ... Spacer member (adjustment mechanism), 210 ... Ejecting optical system (optical) System), 221 ... fiber holder, 226 ... first lens holder, 223 ... second lens holder, 224 ... crystal holder, 225 ... third lens holder, 300 ... engine (internal combustion engine), 301 ... ignition device, 302 ... fuel Ejection mechanism, 303 ... exhaust mechanism, 304 ... combustion chamber, 305 ... piston.

Special table 2013-545280 gazette

Claims (11)

A light source;
An optical transmission member for transmitting light emitted from the light source;
A plurality of optical elements arranged on an optical path of light through the light transmission member;
A laser resonator to which light is input via the plurality of optical elements;
A laser apparatus comprising: an adjustment mechanism for adjusting a position of at least one of the plurality of optical elements.   The laser device according to claim 1, wherein the at least one optical element is an optical element closest to the laser resonator.   The laser apparatus according to claim 1, further comprising an adjustment mechanism for adjusting a position of the laser resonator.   The laser device according to claim 1, wherein the light source is a surface emitting laser.   The laser device according to claim 1, wherein the laser resonator is a Q-switched laser.   The laser device according to claim 5, wherein the laser resonator is ceramic.   The laser device according to claim 5, wherein the laser resonator is a composite crystal in which a laser medium and a saturable absorber are joined.   8. The laser device according to claim 7, wherein the laser medium is a YAG crystal doped with Nd, and the saturable absorber is a YAG crystal doped with Cr.   The laser device according to claim 1, wherein the optical transmission member is an optical fiber. A laser device according to any one of claims 1 to 9,
An ignition device comprising: an optical system that collects light emitted from the laser device. In an internal combustion engine that generates combustion gas by burning fuel,
An internal combustion engine comprising the ignition device according to claim 10 for igniting the fuel.

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