JP2000332327A - Semiconductor laser pumped solid state laser and fabrication thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen the effect of slow axis and fast axis of a semiconductor laser by disposing a laser medium at a position where the beam diameter of light emitted from the semiconductor laser is equalized in the directions of slow axis and fast axis. SOLUTION: A semiconductor laser 1 and a laser medium 6 are disposed at an interval of L wherein L=Z and Z=d/ 2.(tan(θf/2)-tan(θs/2))}. Consequently, the position where the beam diameter is equalized in the directions of slow axis and fast axis is matched with one end face of the laser medium 6. In the formula, Z is the distance from the semiconductor laser 1, d is the length of emitter, and θs is divergence angle in the direction of slow axis. According to the arrangement, effect of the slow axis and fast axis of the semiconductor laser 1 can be lessened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser-pumped solid-state laser, and more particularly to a semiconductor laser-pumped solid-state laser and a solid-state laser capable of reducing the influence of the slow axis and the fast axis of the semiconductor laser with a simple structure. About the method.

[0002]

2. Description of the Related Art A semiconductor laser-excited solid-state laser is one in which output light of a semiconductor laser is incident on a laser medium, which is a solid laser crystal, to excite the laser medium and oscillate laser light. However, the output light of the semiconductor laser has a slow axis parallel to the junction plane of the semiconductor laser and a fast axis perpendicular to the junction plane of the semiconductor laser, which affects the shape of the beam incident on the laser medium.

FIG. 12 is an explanatory diagram showing the relationship between such a slow axis and a fast axis. In FIG. 12, 1 is a semiconductor laser, 2 is a joint plane of the semiconductor laser 1, 10
0 is the output light of the semiconductor laser 1. The divergence angle of the output light 100 in the direction of the fast axis perpendicular to the junction plane 2 of the semiconductor laser 1 indicated by “θf” in FIG. 12 varies depending on each device, but is approximately 60 degrees.
The divergence angle of the semiconductor laser 1 shown in the middle “θs” in the direction of the slow axis parallel to the joint plane 2 is about 20 degrees.

Therefore, the output light 100 of the semiconductor laser 1 is
However, there is a problem that the shape of the incident beam changes depending on the propagation distance when the laser beam is radiated into a laser medium that oscillates a laser beam.

FIG. 13 is a block diagram showing an example of a conventional semiconductor laser pumped solid-state laser in which the influence of the slow axis and the fast axis is reduced. In FIG. 13, reference numerals 1 and 100 denote the same reference numerals as in FIG. 12, reference numeral 3 denotes condensing means such as a lens, reference numeral 4 denotes an optical fiber, reference numeral 5 denotes a laser medium which is a solid laser crystal, and reference numeral 100a denotes a slow axis and a fast axis The output light with reduced influence, 101 is the oscillated laser light.

The output light 100 of the semiconductor laser 1 is condensed on one end of the optical fiber 4 by condensing means 3 such as a lens, propagates through the optical fiber 4, and is emitted from the other end of the optical fiber 4 as output light 100a. You. The output light 100a is incident on the laser medium 5, from which the oscillated laser light 101 is emitted.

Here, the operation of the conventional example shown in FIG. 13 will be described. The output light 100 of the semiconductor laser 1 is affected by the beam shape due to the influence of the slow axis and the fast axis as described above. Such output light 100 is transmitted through the optical fiber 4
When the light propagates through the inside and is emitted from the other end, the emitted light from the other end of the optical fiber 4 can be regarded as the emitted light from the point light source. However, the same divergence angle is obtained.

As a result, the output light 100 of the semiconductor laser 1
Propagates through the optical fiber 4 to become output light 100a that can be regarded as light emitted from a point light source, so that the effects of the slow axis and the fast axis are reduced.

[0009]

However, the prior art shown in FIG. 13 requires optical components such as the light condensing means 3 and the optical fiber 4, and the configuration is not simple. In addition, it is necessary to arrange the semiconductor laser 1, the condensing means 3, and the optical fiber 4 as the components in an optically accurate manner and to stably maintain the positional relationship. For this reason, there has been a problem that not only the configuration becomes complicated but also the cost and reliability may be reduced due to the high precision arrangement. Accordingly, an object of the present invention is to provide a semiconductor laser-excited solid-state laser and a method of forming a solid-state laser capable of reducing the influence of the slow axis and the fast axis of a semiconductor laser with a simple configuration.

[0010]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a semiconductor laser pumped solid-state laser, comprising: a pumping semiconductor laser; A laser medium that is excited by light to oscillate and emit laser light, and that the laser medium is arranged at a position where the beam diameter of the output light of the semiconductor laser in the slow axis direction and the first axis direction is equal. With a simple configuration, the influence of the slow axis and the fast axis of the semiconductor laser can be reduced.

According to a second aspect of the present invention, in the semiconductor laser pumped solid state laser according to the first aspect of the present invention, d / ｛2 · (tan (θf / 2) -tan (θs / 2)) is obtained from the semiconductor laser. ｝ Θf: divergence angle in the fast axis direction θs: divergence angle in the slow axis direction d: length of the emitter Any one of the end faces of the laser medium on the opposite side from the end face on which the output light is incident. By arranging the portions, the influence of the slow axis and the fast axis of the semiconductor laser can be reduced with a simple configuration.

According to a third aspect of the present invention, in the semiconductor laser-excited solid-state laser according to the first and second aspects of the present invention, the output light is transmitted through an end face of the laser medium on which the output light is incident. By providing the coating film for reflecting the laser light oscillated in the laser medium, the influence of the slow axis and the fast axis of the semiconductor laser can be reduced with a simple configuration.

According to a fourth aspect of the present invention, in the semiconductor laser pumped solid-state laser according to the first and second aspects of the present invention, the output light is reflected on an end face of the laser medium on the side where the laser light is emitted. By providing a coating film that reflects most of the laser light oscillated in the laser medium and partially transmits the laser light, the influence of the slow axis and the fast axis of the semiconductor laser can be reduced with a simple configuration. Will be possible.

According to a fifth aspect of the present invention, in the semiconductor laser pumped solid-state laser according to the fourth aspect of the present invention, the crystal plane of the saturable absorber is a [111] plane.
The angle dependence of the transmittance by the polarization plane is reduced.

According to a sixth aspect of the present invention, in the solid-state laser excited by the semiconductor laser according to the first and second aspects of the present invention, a laser having a high peak power is obtained by joining a saturable absorber to the laser medium. You can get light.

According to a seventh aspect of the present invention, in the semiconductor laser-excited solid-state laser according to the first and second aspects of the present invention, a harmonic having a high conversion efficiency can be produced by joining an optical nonlinear substance to the laser medium. Obtainable.

According to an eighth aspect of the present invention, in the method of forming a solid-state laser, the supersaturated absorber is formed in sequence by arranging the supersaturated absorber as a center and then growing the supersaturated absorber to form crystals. By joining a disk-shaped laser medium to the absorber and cutting the formed solid-state laser, the size of the cut can be freely adjusted, so that miniaturization is possible. Since a solid-state laser can be obtained, the cost can be reduced.

According to a ninth aspect of the present invention, in the method for forming a solid-state laser, a composite formed by joining a disk-shaped optical non-linear substance formed in advance and a laser medium formed in a disc shape to the optical non-linear substance is formed. By cutting a disk to form a solid-state laser, the size of the cut can be freely adjusted, so that the size can be reduced. In addition, a plurality of solid-state lasers can be obtained by one forming process, thereby reducing the cost. Becomes possible.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing the configuration of an embodiment of a semiconductor laser-pumped solid-state laser according to the present invention. In FIG. 1, reference numerals 1 and 100 denote the same reference numerals as in FIG. 13, 6 denotes a laser medium which is a solid laser crystal, and 101a denotes an oscillated laser beam.

The output light 100 of the semiconductor laser 1 is directly incident on the laser medium 6, from which the oscillated laser light 101a is emitted.

The operation of the embodiment shown in FIG. 1 will now be described with reference to FIG. FIG. 2 is an explanatory diagram showing the relationship between the slow axis and the fast axis and the distance between the semiconductor laser 1 and the laser medium 6.

As shown in FIG. 1, the distance between the semiconductor laser 1 and the laser medium 6 is arranged to be "L". Then, as shown in FIG. 2, the distance from the semiconductor laser 1 is changed to "
Z, the divergence angle in the fast axis direction is “θf”, the radius of the beam in the fast axis direction is “rf”, the divergence angle in the slow axis direction is “θs”, and the radius of the beam in the slow axis direction is “θ”.
Assuming that rs ”and the length of the emitter are“ d ”, rf = Z · tan (θf / 2) (1) rs = d / 2 + Z · tan (θs / 2) (2)

From the equations (1) and (2), the interval “Z” when the beam radii in the slow axis direction and the beam axis in the fast axis direction are equal is expressed as “rs = tf”, and Z · tan (θf / 2) = D / 2 + Z · tan (θs / 2) Z · {tan (θf / 2) -tan (θs / 2)} = d / 2 Z = d / ｛2 · (tan (θf / 2) -tan (θs) / 2))｝ (3)

For example, the thickness of the laser medium 6 is "D", and the position "Z" at which the beam radii in the slow axis direction and the fast axis direction are equal is the end face of the laser medium 6 on the side where the output light is incident or If it is assumed that they coincide with the opposite end face, the distance between the semiconductor laser 1 and the laser medium 6 at this time is “L”: L = Z = d / ｛2 · (tan (θf / 2) −tan (θs / 2)) {(4) or L = Z−D = d / {2 · (tan (θf / 2) −tan (θs / 2))} − D (5)

As a result, the position where the radius of the beam in the slow axis direction and the radius of the beam in the fast axis direction are equal to one end face of the laser medium 6 as shown in the equation (4) or (5) is simplified. With the configuration, the influence of the slow axis and the fast axis of the semiconductor laser can be reduced.

FIG. 3 is a sectional view showing the configuration of the laser medium 6 in detail. In FIG. 3, 6,100 and 1
Reference numeral 01a is the same as in FIG. 1, reference numeral 7 is a coating film that transmits the output light 100 of the semiconductor laser 1 and reflects the laser light 101a oscillated in the laser medium 6, and reference numeral 8 is the output light of the semiconductor laser 1. 100 and the laser medium 6
This is a coating film that reflects most of the laser light 101a oscillated therein and transmits part of it.

The output light 100 of the semiconductor laser 1 passes through the coating film 7 provided at one end of the laser medium 6 and is incident on the laser medium 6 and is reflected by the coating film 8 provided at the other end.

On the other hand, the laser beam 101a excited by the output light 100 and oscillated is reflected between the coating film 7 and the coating film 8 so that the energy is amplified and a part of the laser beam 101a passes through the coating film 8. Then, the light is emitted as laser output light.

As a result, at one end of the laser medium 6, a coating film for transmitting the output light 100 of the semiconductor laser 1 and reflecting the laser light 101a oscillated in the laser medium 6 is provided. Output light 1 of laser 1
00 reflected from the laser beam 10 and oscillated in the laser medium 6.
The laser beam 101a can be oscillated by providing a coating film that reflects most of the light and transmits part of the light.

A saturable absorber may be joined to the laser medium 6. FIG. 4 is a sectional view showing the details of the configuration of the laser medium portion to which the saturable absorber is joined. FIG.
3, reference numeral 100 denotes the same reference numeral as in FIG. 3, reference numeral 6a denotes a laser medium which is a solid laser crystal, and reference numeral 7a denotes a coating which transmits the output light 100 of the semiconductor laser 1 and reflects the laser light oscillated in the laser medium 6a. A coating film 8a reflects the output light 100 of the semiconductor laser 1, reflects most of the laser light oscillated in the laser medium 6a, and partially transmits the laser light, 9 denotes a saturable absorber, and 101b denotes an oscillated laser light. It is.

The saturable absorber 9 is, for example, Cr ⁴⁺ : YAG (chromium-doped yttrium aluminum garnet) and functions as a passive Q switch. That is, when the intensity of the incident light is low, the saturable absorber 9 has a high absorptivity, and when the intensity of the incident light is high, the absorption of the light is weakened due to the saturation of the absorption. In other words, as the light intensity increases, the absorptance decreases and the light becomes transparent.

The output light 100 of the semiconductor laser 1 passes through the coating film 7a provided at one end of the laser medium 6a and is incident on the laser medium 6a, where the junction surface between the laser medium 6a and the saturable absorber 9 and the saturable absorber 9 and is reflected by a coating film 8 a provided at one end of the saturable absorber 9.

On the other hand, the energy of the laser light 101b excited and oscillated by the output light 100 is amplified while being reflected between the coating films 7a and 8a. However, the laser beam 101b oscillated by the saturable absorber 9 is not absorbed and emitted by the saturable absorber 9 until the intensity of the laser light 101b oscillated by the saturable absorber 9 increases to some extent, so that the laser light is emitted as a pulsed laser beam having a large peak power.

As a result, by joining the saturable absorber 9 to the laser medium 6a, it is possible to obtain a laser beam 101b of a pulse having a large peak power. In addition, the following effects are produced by joining the laser medium 6a and the saturable absorber 9.

That is, the thermal expansion of the laser medium 6a and the saturable absorber 9 due to the energy absorption
Since the concave mirror is formed on the surface of the a and the saturable absorber 9, it becomes possible to select the single mode and oscillate the laser beam 101b. Further, optical adjustment is not required, and the configuration of the optical system can be simplified.

The mode hopping of the longitudinal mode is determined by the thickness of the laser medium 6a corresponding to the length of the resonator, and the smaller the thickness, the larger the width of the mode hopping. If the width of this mode hopping is sufficiently larger than the fluorescence spectrum width of YAG, oscillation occurs only in one mode. In other words, it becomes possible to select the single mode and oscillate the laser beam 101b.

For example, if the thickness of the laser medium 6a is "1 m
In the case of "m", the mode hopping is "83 GHz", which is sufficiently large compared to the fluorescent spectrum width of YAG "30 GHz", so that oscillation occurs only in one mode.

Further, since the number of boundaries is reduced and the loss at the boundaries can be suppressed, the light use efficiency is improved. For example, when the saturable absorber 9 is disposed outside the laser medium 6a, the boundary surface when the emitted laser light 101b is incident on the saturable absorber 9 disposed outside increases. By joining the saturable absorber 9 to the laser medium 6a, the loss at the boundary is reduced.

Further, the saturable absorber 9 serves as the laser medium 6a.
Laser beam 101 with a large power
b can be oscillated, and processing into a microchip becomes easy.

An optical non-linear substance may be bonded to the laser medium 6. FIG. 5 is a sectional view showing the details of the configuration of the laser medium portion to which the optical nonlinear material is bonded. FIG.
In the figure, reference numeral 100 denotes the same reference numeral as in FIG. 3, reference numeral 6b denotes a laser medium which is a solid laser crystal, and reference numeral 7b denotes a coating which transmits the output light 100 of the semiconductor laser 1 and reflects the laser light oscillated in the laser medium 6b. The coating film 8b reflects the output light 100 of the semiconductor laser 1, reflects most of the laser light oscillated in the laser medium 6b, and partially transmits the laser light.
Represents the oscillated laser beam, and 102 represents a harmonic of the laser beam 101b.

The optical non-linear substance is an optical crystal such as KTP (potassium titanyl phosphate: KTiOPO ₄ ), and generates an n-th harmonic with respect to incident light.

The output light 100 of the semiconductor laser 1 passes through the coating film 7b provided at one end of the laser medium 6b and is incident on the laser medium 6b, and the junction surface between the laser medium 6b and the optical nonlinear substance 10 and the optical nonlinear substance 10 Through the inside,
Coating film 8 provided at one end of optical nonlinear substance 10
b.

On the other hand, the laser light 101c excited and oscillated by the output light 100 is amplified between the coating films 7b and 8b while being reflected between the coating films 7b and 8b, and a part of the laser light 101c passes through the coating film 8b. Then, the light is emitted as laser output light. Further, the harmonics 102 of the laser light 101b generated by the optical nonlinear material 10 also pass through the coating film 8b and are emitted as laser output light.

The higher the amount of the incident light on the nonlinear optical material 10, the larger the amount of the higher harmonic wave. The higher the energy of the harmonic, the higher the energy of the harmonic. Therefore, the nonlinear optical material 10 must be disposed in the laser cavity surrounded by the coating films 7 b and 8 b. As a result, higher energy harmonics can be obtained.

That is, the reflectance of the coating film 8b is generally "90% or more", and the energy of about 10 times the energy that can be taken out as laser light exists in the laser cavity. In addition, it becomes about 10 times.

As a result, by joining the optical nonlinear substance 10 to the laser medium 6b, about 10 times the energy in the laser cavity can be utilized as compared with the energy of the external output, so that a higher harmonic of a larger energy is obtained. be able to.

A method for forming such a solid-state laser will be described with reference to FIGS. 6, 7, 8, 9, 10, and 11. FIG. FIG. 6 is a flowchart illustrating the process of the method of forming a solid-state laser, FIG. 7 is a plan view illustrating the crystal growth of a saturable absorber,
8 is a perspective view showing a state in which crystal growth is completed, FIG. 9 is a perspective view showing a formed laser medium, FIG. 10 is a perspective view showing a state in which a saturable absorber and a laser medium are joined, and FIG.
FIG. 4 is a plan view illustrating a cutting method.

In FIGS. 7 to 11, reference numeral 11 denotes C.
r ⁴⁺ : a seed crystal of a saturable absorber such as YAG, 12 is a saturable absorber formed by crystal growth, 13 is a facet, and 14 is a formed laser medium.

In FIG. 6, in S001, the seed crystal 11 of the saturable absorber is disposed at the center, and in S002 in FIG. 6, the saturable absorber is grown by crystal growth.
Are sequentially formed.

For example, as shown in FIG. 7, by using a disc-shaped seed crystal 11 of a saturable absorber, "DR0" in FIG.
By sequentially growing crystals in the directions indicated by 1 "," DR02 "," DR03 "and" DR04 ", the disc-shaped saturable absorber 11 is formed as shown in FIG.

Here, for example, facet 13 corresponds to FIG.
The supersaturated absorbers that grow in the middle “DR02” and “DR03” directions interfere with each other, and have no uniform crystal plane. Therefore, this part cannot be used as a saturable absorber.

Then, in "S003" in FIG. 6, it is joined to the laser medium 14 formed in a disk shape. For example, the saturable absorber 12 or the like shown in FIG. 8 is joined to the previously formed disk-shaped laser medium 14 as shown in FIG. 9, for example, the mirror surface is joined without using an adhesive by Van der Waals force. Thus, a disk-shaped solid laser as shown in FIG. 10 is formed.

The solid laser formed in "S004" in FIG. 6 is cut by a dicing saw or the like. For example, FIG.
As shown by the dashed line in FIG. 1, the disk-shaped solid laser shown in FIG. 10 is cut into a lattice shape.

Finally, "S005" and "S00" in FIG.
By removing the portion of the seed crystal 11 and the portion of the facet 13 that cannot be used as the saturable absorber in 6 ″, the formation of the solid-state laser is completed. For example, FIG.
A solid-state laser as indicated by "LR01" can be obtained. However, description of a method for forming a coating film or the like generated after this process is omitted.

As described above, by forming the solid-state laser, the size of the cut can be freely adjusted, so that the size can be reduced, and a plurality of solid-state lasers can be obtained by one forming step, so that the cost is low. Becomes possible.

In the description of FIGS. 1 and 2, one end face or the other end face of the laser medium 6 is arranged at a position where the beam diameter of the output light of the semiconductor laser 1 in the slow axis direction and the fast axis direction becomes equal. However, the laser medium 6
In other words, it suffices that any part of the laser medium 6 coincides with a position where the beam diameter of the output light of the semiconductor laser 1 in the slow axis direction and the fast axis direction becomes equal.

Further, it is not necessary that the beam diameters of the output light of the semiconductor laser 1 in the slow axis direction and the fast axis direction are strictly equal, and a certain degree of error is allowed in practical use.

Also, in the description of FIG. 3 and the like, it has been described that the coating film 7 and the like transmit the output light of the semiconductor laser and reflect the laser light oscillated in the laser medium. Any coating film that transmits and reflects nearly 100% of the laser light oscillated in the laser medium may be used.

In the description of FIG. 3 and the like, it has been described that the coating film 8 reflects the output light of the semiconductor laser, reflects most of the laser light oscillated in the laser medium, and partially transmits the laser light. 100 laser output light
5% of the laser light reflected in the laser medium and oscillated in the laser medium
Any coating film may be used as long as it transmits about 95% of the design value.

The saturable absorber described with reference to FIG. 4 is exemplified by Cr ⁴⁺ : YAG, but is not limited to this. Of course, the saturable absorber realized by a fine transparent cell containing a dye in a solution is used. It does not matter.

In FIG. 4, it is described that a concave mirror is formed on the surfaces of the laser medium 6a and the saturable absorber 9 due to thermal expansion. However, the concave mirror is similarly formed on the surface of the laser medium 6 alone shown in FIG. Is formed. Therefore, it becomes possible to select the single mode and oscillate the laser beam 101a. Also, optical adjustment is not required, and the configuration of the optical system can be simplified.

The optical non-linear substance described with reference to FIG. 5 is exemplified by KTP, but is not limited to KTP. LiNbO ₃ (lithium niobate), KDP, LB
O, BBO, LiIO ₃ or the like may be used.

Further, in the description of FIGS. 6 to 11, the saturable absorber is illustrated as an example, but a crystal which is an optical nonlinear substance may be used.

In the description of FIGS. 6 to 11, a method of forming a solid-state laser in which a laser medium and a saturable absorber are joined has been exemplified. Although the operation is different, the effects such as miniaturization and reduction of interface reflection are also the same.

The crystal plane of the saturable absorber was changed to [111]
By using a plane, the angle dependence of the transmittance by the polarization plane is reduced.

[0066]

As is apparent from the above description,
According to the present invention, the following effects can be obtained. According to the first to fourth aspects of the present invention, the laser medium is disposed at a position where the radii of the beams of the output light of the semiconductor laser in the slow axis direction and the fast axis direction are equal to each other. It is possible to reduce the influence of the slow axis and the fast axis.

According to the fifth aspect of the present invention, a laser beam having a high peak power can be obtained by joining a saturable absorber to a laser medium. In addition, since a concave mirror is formed on the surface of the laser medium and the saturable absorber due to thermal expansion due to energy absorption of the laser medium and the saturable absorber, it becomes possible to select a single mode and oscillate laser light. Further, optical adjustment is not required, and the configuration of the optical system can be simplified.

Further, since the number of boundary surfaces is reduced and the loss at the boundary can be suppressed, the light use efficiency is improved. Further, since the saturable absorber functions as a radiator for the laser medium, it is possible to oscillate the laser light with a large power. Since a crystal can be joined and cut out, processing into a microchip is also facilitated.

According to the sixth aspect of the present invention, since the crystal plane of the saturable absorber is the [111] plane, the angle dependence of the transmittance by the polarization plane is reduced.

According to the seventh aspect of the present invention, by joining an optical non-linear substance to a laser medium, the energy in the laser cavity is increased by about 10 times compared to a case where an optical non-linear substance is separately arranged. Since it can be used, it is possible to obtain a harmonic having high conversion efficiency.

According to the eighth aspect of the present invention, the supersaturated absorber is placed around the seed crystal, and then the supersaturated absorber is crystal-grown to form the supersaturated absorber in order. Joining the laser medium formed in a shape,
By cutting the formed solid-state laser, it is possible to freely adjust the size of cutting, so it is possible to reduce the size,
Since a plurality of solid-state lasers can be obtained by one forming process, the cost can be reduced.

According to the ninth aspect of the present invention, a large disc is formed by forming a disc-shaped optical nonlinear material in advance and joining the disc-shaped laser medium to the optical nonlinear material. The size of the cut can be freely adjusted by cutting the formed solid-state laser, so that it is possible to reduce the size. Also, it is possible to obtain a plurality of solid-state lasers by one forming process, so that the cost can be reduced. become.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of an embodiment of a semiconductor laser pumped solid-state laser according to the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a slow axis and a fast axis and an interval between a semiconductor laser and a laser medium.

FIG. 3 is a configuration sectional view showing details of a configuration of a laser medium.

FIG. 4 is a configuration sectional view showing details of a configuration of a laser medium portion to which a saturable absorber is joined.

FIG. 5 is a configuration sectional view showing details of a configuration of a laser medium portion to which an optical nonlinear substance is bonded.

FIG. 6 is a flowchart illustrating a process of a method for forming a solid-state laser.

FIG. 7 is a plan view showing crystal growth of a saturable absorber.

FIG. 8 is a perspective view showing a state where crystal growth is completed.

FIG. 9 is a perspective view showing the formed laser medium.

FIG. 10 is a perspective view showing a state where a saturable absorber and a laser medium are joined.

FIG. 11 is a plan view illustrating a cutting method.

FIG. 12 is an explanatory diagram showing a relationship between a slow axis and a fast axis.

FIG. 13 is a configuration block diagram showing an example of a conventional semiconductor laser-pumped solid-state laser in which the effects of the slow axis and the fast axis are reduced.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor laser 2 Junction plane 3 Condensing means 4 Optical fiber 5,6,6a, 6b, 14 Laser medium 7,7a, 7b, 8,8a, 8b Coating film 9,12 Saturated absorber 10 Optical nonlinear material 11 Seed Crystal 13 Facet 100, 100a Output light 101, 101a, 101b, 101c Laser light 102 Harmonic

Claims (9)

[Claims] 1. A semiconductor laser-excited solid-state laser, comprising: a semiconductor laser for excitation; and a laser medium excited by output light of the semiconductor laser to oscillate and emit laser light. A semiconductor laser-excited solid-state laser, wherein the laser medium is disposed at a position where the beam diameters in the slow axis direction and the fast axis direction are equal. 2. From the semiconductor laser, d / {2 · (tan (θf / 2) −tan (θs / 2))} θf: divergence angle in the fast axis direction θs: divergence angle in the slow axis direction d: 2. The semiconductor laser-excited solid-state laser according to claim 1, wherein any part of an end face of the laser medium on a side opposite to the end face on which the output light is incident is located at a distance of length. 3. 3. A coating film for transmitting the output light and reflecting the laser light oscillated in the laser medium is provided on an end face of the laser medium on the side where the output light is incident. 3. A solid-state laser pumped by a semiconductor laser according to claim 1. 4. A coating film that reflects the output light on an end face of the laser medium on the side from which the laser light is emitted, reflects most of the laser light oscillated in the laser medium, and partially transmits the laser light. The semiconductor laser pumped solid-state laser according to claim 1, wherein the solid-state laser is provided. 5. The semiconductor laser-pumped solid-state laser according to claim 1, wherein a saturable absorber is bonded to said laser medium. 6. The semiconductor laser-pumped solid-state laser according to claim 5, wherein the crystal plane of the saturable absorber is a [111] plane. 7. The semiconductor laser-pumped solid-state laser according to claim 1, wherein an optical nonlinear substance is bonded to said laser medium. 8. A method for forming a solid-state laser, comprising: placing a saturable absorber seed crystal at the center, growing the saturable absorber crystal, and sequentially forming a saturable absorber, and forming the saturable absorber in a disk shape. A method for forming a solid-state laser, comprising joining the formed laser medium and cutting the formed solid-state laser. 9. A method for forming a solid-state laser, comprising: joining a disk-shaped optical non-linear substance formed in advance with a laser medium formed in a disc shape to the optical non-linear substance; A method for forming a solid-state laser, comprising forming a laser.