JP2008124087A - Spatial mode synchronous laser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spatial mode synchronous laser for stably oscillating a light having various beam profiles with a lower threshold value, or oscillating one high-output light beam, and moreover spatially deflecting this light beam. <P>SOLUTION: The spatial mode synchronous laser is characterized in including a plurality of laser sources 111 periodically arranged one-dimensionally so that each laser light source is provided with a laser array 11 for emitting the laser beam of almost equal oscillation wavelength toward the free space 131 and a reflecting mirror array 12 formed of a plurality of reflecting mirrors periodically arranged one-dimensionally opposing to the laser array 11 with a predetermined distance toward the free space 131 from the laser sources 111 in the free space 131 to emit the laser beam from each reflecting mirror 121. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention oscillates light having various beam profiles by spatially synchronizing the phases of oscillation light from a plurality of laser light sources constituting a laser array, and oscillates one high-power beam. The present invention relates to a spatial mode-locked laser capable of spatially shaking an output beam.

  In order to synchronize the phases of the laser beams generated by the incoherent laser light sources, as shown in FIG. 9A, the laser device 8 using mode coupling between the waveguides 81 close to each other, as shown in FIG. ), A plurality of laser light sources 911 that emit laser light in a direction parallel to the laminated surface are periodically arranged to form a laser array 91, and the reflecting mirror 92 is placed in the free space 93 so as to face the laser array 91. There is known a laser apparatus 9 in which cylindrical lenses 941 and 942 are arranged between a laser array 91 and a reflecting mirror 92 so that light is collimated therebetween.

  Specifically, the laser device disclosed in Patent Document 1 includes a laser light emitting unit (edge emitting laser) in which a plurality of active regions that emit laser light are arranged in a direction parallel to the active layer, and a plurality of active regions. And a collimating lens that suppresses the beam divergence of the laser light emitted from the laser beam. This collimating lens reflects part of each laser beam emitted from the active region to the active region adjacent to the active region, and the optical path length of the reflected light is (1/4) × (integer multiple of Talbot length) ), Each laser beam can be phase-synchronized.

The laser device disclosed in Patent Document 2 includes a Talbot spatial filter so as to set a fundamental transverse mode vibration in an array of laser devices that feed back a surface radiation distribution. In this laser device, the array is composed of a plurality of first and second subarrays of semiconductor laser devices arranged in parallel, and the first subarray and the second subarray are formed by a free propagation region having a length equal to the Talbot distance. It is separated. These first and second subarrays are composed of a plurality of islands of light absorbing material in the free propagation region.
JP 2004-281890 A Japanese Unexamined Patent Publication No. 6-45696

  By the way, in the laser devices of Patent Documents 1 and 2, the lasers of the semiconductor laser array do not always oscillate stably, and the operation tends to become unstable. Further, when the number of laser light sources constituting the array increases, the threshold difference in gain between modes becomes small, and it becomes difficult to control the oscillation mode. Furthermore, since the loss of the resonator is large, the oscillation threshold value of the laser is increased and the oscillation efficiency is deteriorated. Moreover, it only has a function of converging oscillation light emitted from a large number of lasers into one beam.

  The present invention has been proposed in order to solve the above-described problem, and has light beams having various beam profiles by spatially synchronizing the phases of oscillation light from a plurality of light sources constituting a laser array. It is an object to provide a spatially mode-locked laser that can stably oscillate at a low threshold value, or can oscillate one high-power beam, and that can spatially oscillate this beam. .

The gist of the spatial mode-locked laser of the present invention is (1) to (16).
(1) A laser array comprising a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each laser light source emitting laser light having substantially the same oscillation wavelength toward free space;
A reflector array comprising a plurality of reflectors periodically spaced one-dimensionally or two-dimensionally so as to face the laser array at a predetermined distance from the laser light source in the free space toward the emission direction; A spatial mode-locked laser, wherein a laser beam is emitted from each of the reflecting mirrors or lasers.

(2) a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each of the laser light sources emitting a laser beam having substantially the same oscillation wavelength toward a laser beam diffraction region;
A slab waveguide made of glass or electro-optic crystal when the plurality of laser light sources are arranged one-dimensionally, and a transparent block made of glass or electro-optic crystal when the plurality of laser light sources are arranged two-dimensionally A laser diffraction region that is a waveguide of the body;
A reflecting mirror array comprising a plurality of reflecting mirrors periodically and one-dimensionally or two-dimensionally arranged so as to face the laser array at a predetermined distance from the laser light source in the laser light diffraction region in the emission direction; And a spatial mode-locked laser, wherein a laser beam is emitted from each of the reflecting mirrors.

(3) The spatial mode-locked laser according to (2), wherein the width of the laser beam diffraction region is at least two times and not more than 100 times the width of the laser array.

(4) The period of the plurality of reflecting mirrors is an integral multiple of the period of the plurality of laser light sources or 1 / (integer) multiple, wherein (1) to (3) Spatial mode-locked laser.

(5) The plurality of laser light sources are edge-emitting lasers or surface-emitting lasers, and the predetermined distance between the laser array and the reflector array is an integral multiple of nd ² / (2λ) (where d Is the periodic interval of the laser light source, λ is the oscillation wavelength of the laser light source, and n is the refractive index of the medium between the laser array and the reflector array). The spatially mode-locked laser described.

(6) The spatial mode-locked laser according to any one of (1) to (5), wherein a waveguide type modulator or a spatial modulator is disposed after the plurality of reflecting mirrors.

(7) The spatial mode-locked laser according to (6), wherein the modulator is a phase modulator or an amplitude modulator.

(8) The spatial mode-locked laser according to any one of (1) to (7), wherein the plurality of reflecting mirrors have a characteristic (periodic filter characteristic) that reflects only wavelengths at a constant interval.

(9) a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each laser light source emitting a laser beam having substantially the same oscillation wavelength toward free space;
A second laser comprising a plurality of laser light sources that are periodically spaced one-dimensionally or two-dimensionally so as to face the first laser array, separated from the laser light source in the free space by a predetermined distance in the emission direction. A spatial mode-locked laser comprising: an array; and laser light is emitted from the second laser array.

(10) a first laser array comprising a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, wherein each laser light source emits laser light having substantially the same oscillation wavelength toward a laser light diffraction region; ,
A slab waveguide made of glass or electro-optic crystal when the plurality of laser light sources are arranged one-dimensionally, and a transparent block made of glass or electro-optic crystal when the plurality of laser light sources are arranged two-dimensionally A laser diffraction region that is a waveguide of the body;
A first light source comprising a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally so as to be opposed to the first laser array at a predetermined distance in the emission direction from the laser light source in the laser light diffraction region. A spatial mode-locked laser, wherein the laser beam is emitted from the second laser array.

(11) The spatial mode-locked laser as set forth in (10), wherein the width of the laser beam diffraction region is at least 2 to 4 times the width of the laser array.

(12) The period of the laser light source constituting the second laser array is an integral multiple or 1 / (integer) multiple of the period of the laser light source constituting the first laser array. The spatial mode-locked laser according to any one of (9) to (11).

(13) A laser light source constituting the first laser array and the second laser array is composed of an edge-emitting laser or a surface-emitting laser, and is disposed between the first laser array and the second laser array. The predetermined distance is an integral multiple of nd ² / (2λ) (where d is the periodic interval of the laser light source, λ is the oscillation wavelength of the laser light source, and n is the refractive index of the medium between the laser array and the reflector array). The spatial mode-locked laser according to any one of (9) to (12), wherein

(14) The waveguide modulator or the spatial modulator is disposed at the subsequent stage of the laser light source constituting the second laser array, according to any one of (9) to (13) Spatial mode-locked laser.

(15) The spatial mode-locked laser according to (14), wherein the modulator is a phase modulator or an amplitude modulator.

(16) Comprising a plurality of edge emitting lasers periodically arranged one-dimensionally or two-dimensionally, each laser light source emits laser light having substantially the same oscillation wavelength toward a laser light diffraction region through a wavelength filter array. A laser array to
When the plurality of edge emitting lasers are arranged one-dimensionally, it is a slab waveguide made of glass or electro-optic crystal, and when the plurality of laser light sources are arranged two-dimensionally, it is transparent made of glass or electro-optic crystal. A laser beam diffraction region composed of a waveguide of a block body;
A reflector array composed of a plurality of reflectors periodically spaced one-dimensionally or two-dimensionally so as to face the laser array at a predetermined distance in the emission direction from the edge-emitting laser in the laser beam diffraction region A spatial mode-locked laser characterized in that laser light is emitted from the end of each of the edge-emitting lasers opposite to the wavelength filter array.

The spatial mode-locked laser of the present invention can align the phase of the light emitted from each laser light source of the laser array, and also modulates the phase of the oscillating light to swing the light beam (scan) and freely adjust the beam profile. (There is no need for a mechanical reflector), and the frequency comb can be generated spatially separated, so that it can be applied to the synthesis of short light pulses.
That is, the spatial mode-locked laser of the present invention is used not only as an optical pulse generation light source but also as a light beam generation device for high-power laser processing.

  Embodiments of the present invention will be described below. In the drawings referred to below, the diffraction state of the laser beam is schematically shown for easy understanding of the embodiment, but the actual self-coupling state is not displayed. In addition, although added as a precaution, the phase-synchronized light is indicated by arrows, the directions of these arrows are for convenience, and do not represent the directions that actually occur.

<< First Embodiment >>
FIG. 1A is an explanatory view showing a first embodiment of the present invention. In FIG. 1A, the spatial mode-locked laser 1 </ b> A includes a laser array 11 and a reflector array 12. The laser array 11 includes a plurality of laser light sources 111 periodically arranged one-dimensionally, and each laser light source 111 emits laser light having substantially the same oscillation wavelength toward the free space 131.

  In the present embodiment, the laser light source 111 is a surface emitting laser. FIG. 2A shows an example of a laser light source 111 (surface emitting laser). In FIG. 2A, a surface emitting laser is denoted by reference numeral 7 for convenience of explanation. The surface emitting laser 7 has a lower electrode 71 on one surface (lower surface) of a substrate 70, a lower surface Bragg reflector (lower surface DBR) 72 is formed on the substrate 70, and an active layer 73 is formed in a predetermined region of the lower surface DBR 72. The upper surface Bragg reflector (upper surface DBR) 74 is formed, and the upper ring electrode 75 is formed on the upper surface Bragg reflector 74.

  The reflector array 12 is a plurality of one-dimensionally arranged at the same period as the laser light source 111 of the laser array 11 so as to be separated from the laser light source 111 of the free space 131 by a predetermined distance in the emission direction and to face the laser array 11 It consists of a reflecting mirror 121.

  As shown in FIG. 2B, the reflecting mirror 121 is manufactured by forming the reflecting mirror 121 and the light absorption layer 122 on the surface of the glass substrate 124. The light absorption layer 122 is formed in a region other than the reflecting mirror 121. Further, as shown in FIG. 2C, the reflecting mirror 121 is manufactured by forming the reflecting mirror 121 and the antireflection film 123 on the surface of the glass substrate 124. The antireflection film 123 is formed in a region other than the reflecting mirror 121. In FIGS. 2B and 2C, the laser light L is not reflected by portions other than the reflecting mirror 121.

The predetermined distance between the laser array 11 and the reflector array 12 is an integral multiple of d ² / (2λ) (where d is the periodic interval of the laser light source 111 and λ is the oscillation wavelength of the laser light source 111). Further, the period interval d is set sufficiently larger than the wavelength λ.

In this embodiment, a surface emitting laser is used as the laser light source 111, and an array of reflecting mirrors 121 (reflecting mirror array 12) corresponding to a one-dimensional arrangement period of each laser light source 111 is used. Therefore, since there is no reflection from unnecessary portions, there is an advantage that the S / N characteristic is improved and the oscillation mode is stabilized.
In the example of FIG. 1A, the laser array 11 and the reflector array 12 may be two-dimensionally arranged.

<< Second Embodiment >>
FIG. 1B is an explanatory view showing a second embodiment of the present invention. In FIG. 1B, the spatial mode-locked laser 1B includes a laser array 11, a reflector array 12, and a slab waveguide 132.
As in the first embodiment, the laser array 11 includes a plurality of laser light sources 111 periodically arranged one-dimensionally. Each laser light source 111 propagates laser light having substantially the same oscillation wavelength in the slab waveguide 132. . The laser light source 111 is a surface emitting laser as in the first embodiment.

As in the first embodiment, the reflector array 12 is spaced from the laser light source 111 of the slab waveguide 132 by a predetermined distance in the emission direction and is opposed to the laser array 11 at the same periodic intervals as the laser light sources 111. It is composed of a plurality of reflecting mirrors 121 (see FIGS. 2B and 2C) arranged one-dimensionally, and the predetermined distance between the laser array 11 and the reflecting mirror array 12 is n × [d ² / (2λ)]. (Where d is the periodic interval of the laser light source 111, λ is the oscillation wavelength of the laser light source 111, and n is the refractive index of the slab waveguide 132).

The slab waveguide 132 is made of glass, plastic, or electro-optic crystal.
In the above embodiment, the laser array 11 and the reflector array 22 may be two-dimensionally arranged. In this case, the laser beam diffraction region can be constituted by a waveguide of a transparent block body made of glass, plastic or electro-optic crystal.
<< Third Embodiment >>

  FIG. 1C is an explanatory view showing a third embodiment of the present invention. In FIG. 1C, a spatial mode-locked laser 1C includes a laser array 11, a reflector array 12, and a slab waveguide 133, like the spatial mode-locked laser 1B in the second embodiment. However, in the third embodiment, the width of the slab waveguide 133 is selected to be several times or more (usually at least twice or more and 100 times or less) the width of the laser array 11.

  In this embodiment, since the width of the slab waveguide 133 is wide, the laser light does not spread to the side of the slab waveguide 133, so that the waveguide mode does not stand. Thereby, the slab waveguide 133 can be handled substantially the same as the free space of the first embodiment (FIG. 1A), and a stable operation is performed.

<< 4th Embodiment >>
FIG. 3A is an explanatory view showing a fourth embodiment of the present invention. In FIG. 3A, the spatial mode-locked laser 2 </ b> A includes a first laser array 21 and a second laser array 22. The first laser array 21 includes a plurality of laser light sources 211 periodically arranged one-dimensionally, and each laser light source 211 emits laser light having substantially the same oscillation wavelength toward the free space 231.

The second laser array 22 is primary at the same periodic interval as the first laser array 21 so as to be separated from the laser light source 211 in the free space 231 by a predetermined distance in the emission direction and to face the first laser array 21. It consists of a plurality of laser light sources 221 originally arranged.
That is, in the fourth embodiment, the reflector array 12 in the first embodiment is replaced with a laser array (reference numeral 22 in the present embodiment).
In this embodiment, since the first laser array 21 and the second laser array 22 are arranged on both sides of the resonator space (free space 231), the oscillation threshold value can be set even if the resonator loss is large. As a result, the spatially mode-locked laser can be efficiently oscillated. Further, as in the first embodiment, since there is no unnecessary portion, there is an advantage that the S / N characteristic is improved and the oscillation mode is stabilized.
In the example of FIG. 3A, the laser array 21 and the reflector array 22 may be two-dimensionally arranged.

<< 5th Embodiment >>
FIG. 3B is an explanatory view showing a fifth embodiment of the present invention. In FIG. 3B, the spatial mode-locked laser 2 </ b> B includes a first laser array 21, a second laser array 22, and a slab waveguide 232.
As in the fourth embodiment, the first laser array 21 and the second laser array 22 are composed of a plurality of laser light sources 211 and 221 periodically arranged one-dimensionally. These laser light sources are the same as those in the first embodiment. Similarly, it is a surface emitting laser.
In the fifth embodiment, the reflector array 12 in the second embodiment is replaced with a laser array (reference numeral 22 in the present embodiment).

<< 6th Embodiment >>
FIG. 3C is an explanatory view showing a sixth embodiment of the present invention. In FIG. 3C, a spatial mode-locked laser 2C includes a first laser array 21, a second laser array 22, and a slab waveguide (laser beam diffraction) as in the spatial mode-locked laser 2B in the fifth embodiment. Area) 23. However, in the sixth embodiment, the width of the slab waveguide 233 is selected to be several times or more (usually at least twice or more and 100 times or less) the width of the first laser array 21.
As in the third embodiment of FIG. 1C, in this embodiment, the waveguide mode does not stand because the width of the slab waveguide 233 is wide. Thereby, the effect which has both the effect in 3rd Embodiment and the effect in 4th Embodiment can be show | played.

<< 7th Embodiment >>
4 (A) to 4 (C) and FIGS. 5 (A) to 5 (D) show the arrangement of laser arrays (reference numeral 11) in the spatial mode-locked lasers 1A to 1C shown in FIGS. 1 (A) to 1 (C). It is embodiment which shows the case where a space | interval and the arrangement | sequence space | interval of a reflective mirror array (code | symbol 12) differ.

  4A to 4C, when the arrangement interval (distance between laser light sources 121) of the reflector array (reference numeral 12) is larger than the arrangement interval (distance between laser light sources 111) of the laser array 11 (for example, 5 (A) to (C), when the arrangement interval of the reflector array (reference numeral 12) is smaller than the arrangement interval of the laser array 11 (for example, 1/2 times, (In case of 1/4 times).

In the spatial mode-locked lasers 2A to 2C shown in FIGS. 3A to 3C, the arrangement interval of the first laser array (reference numeral 21) and the arrangement interval of the second laser array (reference numeral 22) Can be configured differently.
With the configuration as described above, the laser light emitted from the spatial mode-locked laser can be a spherical wave (divergent wave or convergent wave), and the same effect as when a lens is arranged can be achieved.

<< Eighth Embodiment >>
FIG. 6 shows an embodiment in which a spatial modulator (for example, a transmissive liquid crystal spatial modulator or the like) 14 is arranged in the subsequent stage of the reflector array (reference numeral 12) of the spatial mode-locked laser 1A shown in FIG. It is explanatory drawing which shows. In the present embodiment, the beam profile of the emitted light can be changed, or the beam can be converged into one beam and scanned.
Also in the spatial mode-locked laser 2A shown in FIG. 3A, the above-described spatial modulator can be arranged after the second laser array.

<< Ninth Embodiment >>
FIG. 7 shows an embodiment in which a spatially mode-locked laser 1B shown in FIG. 1B has a slab waveguide and a monolithically one-dimensional waveguide type modulator array arranged after the reflector array (reference numeral 12). It is explanatory drawing which shows. As the material at this time, glass, electro-optic crystal or the like is used.
In the present embodiment, the modulator array 15 enables beam control. In addition, the modulator array 15 can be arranged after the reflecting mirror array (reference numeral 12) of the spatial mode-locked laser 1C shown in FIG. 1C, as shown in FIGS. 3B and 3C. The modulator array described above can be arranged after the second laser array of the spatial mode-locked lasers 2B and 2C.

<< 10th Embodiment >>
FIG. 8A is an explanatory diagram of a tenth embodiment of the spatial mode-locked laser according to the present invention. In FIG. 8A, the spatial mode-locked laser 5 includes a laser array 51, a reflector array 54, and a slab waveguide (laser light diffraction region) 53.
The laser array 51 includes a plurality of laser light sources (edge emitting lasers) 511 periodically arranged one-dimensionally. The laser light source 511 transmits laser light having substantially the same oscillation wavelength to the wavelength filter array 52 (wavelength filters F1, F2, and F2). F3,..., And FN) are emitted toward the slab waveguide 53. As shown in FIG. 8B, the wavelength filters F1, F2, F3,..., FN have a characteristic that only one of the laser oscillation modes is selectively transmitted in order.

The reflecting mirror array 52 is composed of a plurality of reflecting mirrors 521 that are spaced apart from the laser light source 511 of the slab waveguide 53 by a predetermined distance in the emission direction and periodically arranged so as to face the laser array 51. The predetermined distance between the array 51 and the reflector array 52 is n × [d ² / (2λ)] (where d is the periodic interval of the laser light source 511, λ is the oscillation wavelength of the laser light source 511, and n is the slab guide. It is selected to be an integral multiple of the refractive index of the waveguide 532. The slab waveguide (laser light diffraction region) 53 is made of glass or an electro-optic crystal.
In the present embodiment, laser light is emitted from the end of the laser light source 511 opposite to the wavelength filter array 54.
In this structure, it is needless to say that the same waveguide type modulator array as that of the ninth embodiment can be arranged on the right side of the laser light source 511.

(A) is explanatory drawing which shows 1st Embodiment of this invention, (B) is explanatory drawing which shows 2nd Embodiment of this invention, (C) is explanatory drawing which shows 3rd Embodiment of this invention. (A) is an explanatory view of a surface emitting laser, (B) is a diagram showing a slab waveguide whose periphery is a light absorption layer, and (C) is a slab waveguide whose periphery is an antireflection film. FIG. (A) is explanatory drawing which shows 4th Embodiment of this invention, (B) is explanatory drawing which shows 5th Embodiment of this invention, (C) is explanatory drawing which shows 6th Embodiment of this invention. FIGS. 1A to 1C show embodiments in which the arrangement intervals of the reflecting mirrors are larger than the arrangement intervals of the laser arrays in the spatial mode-locked lasers 1A to 1C shown in FIGS. It is explanatory drawing shown. FIGS. 1A to 1C show embodiments in which the arrangement intervals of the reflecting mirrors are smaller than the arrangement intervals of the laser arrays in the spatial mode-locked lasers 1A to 1C shown in FIGS. It is explanatory drawing shown. It is explanatory drawing which shows embodiment which has arrange | positioned the spatial modulator in the back | latter stage of the reflector array of the spatial mode-locked laser shown to FIG. 1 (A). It is explanatory drawing which shows embodiment which has arrange | positioned the slab waveguide and the monolithic one-dimensional waveguide type modulator array in the back | latter stage of the reflector array of the space mode-locked laser shown to FIG. 1 (B). (A) is explanatory drawing of 10th Embodiment of the spatial mode locking laser of this invention, (B) is explanatory drawing which shows the transmission characteristic of a wavelength filter. (A) is an explanatory view of a conventional laser device using mode coupling between waveguides 81 that are close to each other, (B) is a plurality of laser light sources that emit laser light in a direction parallel to the laminated surface, and laser It is explanatory drawing of the conventional laser apparatus which formed the reflective mirror facing the array.

Explanation of symbols

1A, 1B, 1C, 2A, 2B, 2C Spatial mode-locked laser 11, 21, 51 Laser array 12, 22, 54 Reflector array 15 Modulator array 52 Wavelength filter array 111, 211, 511 Laser light source 112, 212, 541 Reflector 131,231 Free space 132,133,232,233,53 Slab waveguide 521 (F1, F2, ..., FN) Wavelength filter

Claims (16)

A plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, and each laser light source emits laser light having substantially the same oscillation wavelength toward free space; and
A reflector array comprising a plurality of reflectors periodically spaced one-dimensionally or two-dimensionally so as to face the laser array at a predetermined distance from the laser light source in the free space toward the emission direction; A spatial mode-locked laser, wherein a laser beam is emitted from each of the reflecting mirrors or lasers. A plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each laser light source emitting a laser beam having substantially the same oscillation wavelength toward a laser beam diffraction region; and
A slab waveguide made of glass or electro-optic crystal when the plurality of laser light sources are arranged one-dimensionally, and a transparent block made of glass or electro-optic crystal when the plurality of laser light sources are arranged two-dimensionally A laser diffraction region that is a waveguide of the body;
A reflecting mirror array comprising a plurality of reflecting mirrors periodically and one-dimensionally or two-dimensionally arranged so as to face the laser array at a predetermined distance from the laser light source in the laser light diffraction region in the emission direction; And a spatial mode-locked laser, wherein a laser beam is emitted from each of the reflecting mirrors.   3. The spatial mode-locked laser according to claim 2, wherein a width of the laser beam diffraction region is at least two times and not more than 100 times a width of the laser array.   4. The spatial mode-locked laser according to claim 1, wherein a period of the plurality of reflecting mirrors is an integral multiple or 1 / (integer) multiple of a period of the plurality of laser light sources. The plurality of laser light sources are edge-emitting lasers or surface-emitting lasers, and the predetermined distance between the laser array and the reflector array is an integral multiple of nd ² / (2λ) (where d is a laser light source) 5. The spatial mode synchronization according to claim 1, wherein λ is an oscillation wavelength of the laser light source, and n is a refractive index of a medium between the laser array and the reflector array). laser.   6. The spatial mode-locked laser according to claim 1, wherein a waveguide type modulator or a spatial modulator is disposed after the plurality of reflecting mirrors.   The spatially mode-locked laser according to claim 6, wherein the modulator is a phase modulator or an amplitude modulator.   8. The spatial mode-locked laser according to claim 1, wherein the plurality of reflecting mirrors have a characteristic of reflecting only wavelengths at a constant interval. A plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each laser light source emitting a laser beam having substantially the same oscillation wavelength toward free space;
A second laser comprising a plurality of laser light sources that are periodically spaced one-dimensionally or two-dimensionally so as to face the first laser array, separated from the laser light source in the free space by a predetermined distance in the emission direction. A spatial mode-locked laser comprising: an array; and laser light is emitted from the second laser array. A plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally, each laser light source emitting a laser beam having substantially the same oscillation wavelength toward a laser beam diffraction region;
A slab waveguide made of glass or electro-optic crystal when the plurality of laser light sources are arranged one-dimensionally, and a transparent block made of glass or electro-optic crystal when the plurality of laser light sources are arranged two-dimensionally A laser diffraction region that is a waveguide of the body;
A first light source comprising a plurality of laser light sources periodically arranged one-dimensionally or two-dimensionally so as to be opposed to the first laser array at a predetermined distance in the emission direction from the laser light source in the laser light diffraction region. A spatial mode-locked laser, wherein the laser beam is emitted from the second laser array.   11. The spatial mode-locked laser according to claim 10, wherein the width of the laser beam diffraction region is at least 2 to 4 times the width of the laser array.   10. The period of the laser light source constituting the second laser array is an integral multiple or 1 / (integer) multiple of the period of the laser light source constituting the first laser array. To 11. The spatially mode-locked laser according to any one of 11 to 11. The laser light source constituting the first laser array and the second laser array is an edge emitting laser or a surface emitting laser, and the predetermined distance between the first laser array and the second laser array. Is an integral multiple of nd ² / (2λ) (where d is the periodic interval of the laser light source, λ is the oscillation wavelength of the laser light source, and n is the refractive index of the medium between the laser array and the reflector array). The spatially mode-locked laser according to any one of claims 9 to 12, characterized in that:   The spatial mode-locked laser according to any one of claims 9 to 13, wherein a waveguide type modulator or a spatial modulator is arranged at a subsequent stage of a laser light source constituting the second laser array.   The spatially mode-locked laser according to claim 14, wherein the modulator is a phase modulator or an amplitude modulator. A laser array comprising a plurality of edge emitting lasers periodically arranged one-dimensionally or two-dimensionally, wherein each laser light source emits laser light having substantially the same oscillation wavelength toward a laser light diffraction region via a wavelength filter array When,
When the plurality of edge emitting lasers are arranged one-dimensionally, it is a slab waveguide made of glass or electro-optic crystal, and when the plurality of laser light sources are arranged two-dimensionally, it is transparent made of glass or electro-optic crystal. A laser beam diffraction region composed of a waveguide of a block body;
A reflector array composed of a plurality of reflectors periodically spaced one-dimensionally or two-dimensionally so as to face the laser array at a predetermined distance in the emission direction from the edge-emitting laser in the laser beam diffraction region A spatial mode-locked laser characterized in that laser light is emitted from the end of each of the edge-emitting lasers opposite to the wavelength filter array.

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