JP4927051B2 - Semiconductor laser light output device and solid-state laser rod excitation module - Google Patents

Description

  The present invention relates to a semiconductor laser light output device that outputs laser light using a semiconductor laser, and to a solid laser rod excitation module that obtains a desired laser light by optically exciting a solid laser rod with the semiconductor laser light, and particularly to an array semiconductor laser. And a semiconductor laser light output device that can obtain semiconductor laser light synthesized with high density using a stack type semiconductor laser with high efficiency, and a semiconductor laser light to excite a solid laser rod with high power and high efficiency, The present invention relates to a solid-state laser rod excitation module capable of obtaining high-beam quality laser light.

  The semiconductor laser beam output device obtains a semiconductor laser beam in which power is synthesized with high density using laser beam emitted from the semiconductor laser (hereinafter also referred to as semiconductor laser beam). In particular, in order to excite a solid laser rod with high power and high efficiency by using this semiconductor laser light output device and to obtain a laser beam with high beam quality, it is necessary to focus the semiconductor laser light by any method. Significantly affects energy use efficiency.

  As a solid-state laser rod excitation module using such a semiconductor laser light output device, an array semiconductor laser in which a plurality of laser light emitting ends of a semiconductor laser are integrated in the slow axis direction is combined with the slow axis direction and the solid laser rod axial direction. (Semiconductor lasers generally have an elliptical near-field image due to their characteristics, and the laser beam is aligned in two orthogonal axes centered on the optical axis of the laser beam.) The divergence angle is different, where the direction in which the divergence angle of the laser beam output at the emitting end of the semiconductor laser beam is small is the slow axis direction, and the direction in which the divergence angle of the laser beam output perpendicular to the slow axis is large is the fast axis. In a side-pumped solid-state laser rod pumping module that achieves higher output by With the configuration in which a single pass, since the cross-sectional area of the solid-state laser rod is small, can not be efficient excitation of the solid-state laser rod. For this reason, conventionally, semiconductor laser light is introduced into a reflecting cylinder arranged around a solid laser rod and confined in the reflecting cylinder, so that the solid laser rod is passed through a plurality of times to efficiently excite the solid laser rod. The method of performing is used.

  In this method, when the confinement efficiency of the semiconductor laser light in the reflecting cylinder is high, the efficiency of excitation of the solid laser rod increases. However, in order to increase the confinement efficiency of the semiconductor laser light in the reflecting cylinder, It is necessary to reduce the escape of the semiconductor laser light from the semiconductor laser light entrance provided in the cylinder, that is, to make the semiconductor laser light entrance as small as possible.

  In general, a stacked semiconductor laser is used as a semiconductor laser in order to further increase the output. A stack type semiconductor laser is configured by laminating a plurality of bar-shaped elements, each of which is configured by integrating a plurality of laser light emitting ends in the slow axis direction, in the fast axis direction.

  In addition, in order to obtain a laser beam with high beam quality by exciting the solid laser rod, it is necessary to suppress the wavefront aberration of the solid laser rod itself due to heat generated in the solid laser rod when the solid laser rod is excited. For this reason, the solid state laser rod is irradiated with the semiconductor laser beam as uniformly as possible, the intensity distribution of the semiconductor laser beam in the solid state laser rod is made axisymmetric and uniform, and the temperature distribution in the solid state laser rod is changed to the secondary axis. By using a symmetric distribution, it is desirable that the solid laser rod be an ideal graded / refractive index lens without wavefront aberration.

  However, in the conventional solid-state laser rod excitation module, the portion where the semiconductor laser light introduced from the semiconductor laser light entrance first enters the solid-state laser rod, that is, the portion facing the end surface of the semiconductor laser light entrance of the solid-state laser rod Since the semiconductor laser light is incident on the solid-state laser rod without being attenuated, the temperature distribution generated by the excitation by the semiconductor laser light in the solid laser rod is difficult to be a second-order axisymmetric distribution. Therefore, in the conventional solid-state laser rod excitation module, low-beam quality laser light with an average power of about 1 kW is realized, but high-beam quality laser light with an average power of about 100 W is realized. Was not.

Conventional Example 1
FIG. 19 is a cross-sectional view showing a configuration of a solid-state laser rod excitation module of Conventional Example 1 described in, for example, Reference 1 “S. Fujikawa et al., In technical digest of Advanced Solid-State Lasers '97, p296, 1997”. It is. In the figure, 101 is a solid-state laser rod excitation module, 102 is a solid-state laser rod, 103 is a cylindrical cooling sleeve that is transparent to semiconductor laser light, and surrounds the solid-state laser rod 102 substantially coaxially with the solid-state laser rod 102. A cooling liquid for cooling the solid-state laser rod 102 is circulated. Reference numeral 104 denotes a cylindrical diffusive reflecting cylinder that diffuses and reflects semiconductor laser light, and is disposed substantially coaxially with the solid laser rod 102 so as to surround the solid laser rod 102 and the cooling sleeve 103, thereby reflecting and confining the semiconductor laser light. have. Reference numeral 105 denotes a semiconductor laser configured by integrating a plurality of laser light emitting ends parallel to the axial direction of the solid-state laser rod 102. In the illustrated example, the solid-state laser rod 102 is arranged so that the axial direction thereof is parallel to the slow axis direction of the semiconductor laser 105. A semiconductor laser beam output device is constituted only by the semiconductor laser 105. Reference numeral 107 denotes a semiconductor laser light introducing means, which is provided on the diffusive reflector 104 and is made of thin glass.

Next, the operation will be described.
The laser light emitted from the semiconductor laser 105 is introduced toward the solid laser rod 102 in the diffusive reflector 104 while being totally reflected by the upper and lower surfaces of the thin glass as the semiconductor laser light introducing means 107. The semiconductor laser light introduced into the diffusive reflecting cylinder 104 enters the solid laser rod 102 and is partially absorbed. The remaining semiconductor laser light transmitted through the solid-state laser rod 102 is diffusely reflected by the diffusive reflector 104 and is uniformly distributed in the diffusive reflector 104. In FIG. 19, this state is indicated by an arrow indicated by a broken line. The uniformly distributed semiconductor laser light irradiates the solid laser rod 102 uniformly. The heat generated in the solid laser rod 102 is removed from the outer periphery of the solid laser rod 102 by the coolant circulating in the cooling sleeve 103.

  In the solid-state laser rod excitation module 101 of Conventional Example 1, the area of the portion of the semiconductor laser light introducing means 107 made of thin glass located on the inner surface of the diffusive reflector 104 is small. The escape of the semiconductor laser light is small, and the solid laser rod 102 is excited with high efficiency.

Conventional Example 2
20 and FIG. 21 show the semiconductor laser light output device of Conventional Example 2 and the solid state shown in Reference 2, “H. Bruesselbach et al., In technical digest of Advanced Solid-State Lasers '97, P285, 1997”, respectively. FIG. 20 is a diagram showing a configuration of a laser rod excitation module, FIG. 20 is a cross-sectional view of the semiconductor laser light output device along the fast axis direction, and FIG. 21 is a solid laser rod excitation using the semiconductor laser light output device shown in FIG. It is sectional drawing cut in the direction perpendicular | vertical to the axial direction of the solid-state laser rod of a module. In the figure, 111 is a solid-state laser rod excitation module, 112 is a solid-state laser rod, 113 is a cooling sleeve, and has a cylindrical shape transparent to the semiconductor laser light, and is substantially coaxial with the solid-state laser rod 112. The laser rod 112 is disposed around. In addition, a coolant for cooling the solid laser rod 112 circulates in the interior. Reference numeral 114 denotes a specular reflecting reflecting cylinder having a cylindrical shape that is specularly reflecting with respect to the semiconductor laser light, and is disposed substantially coaxially with the solid laser rod 112 and surrounding the solid laser rod 112 and the cooling sleeve 113. ing.

  Reference numeral 117 denotes a semiconductor laser light introducing means, which is provided in the specular reflective reflector 114 and is output from a semiconductor laser light output device comprising a stack type semiconductor laser 121, a cylindrical lens array 122a, and a condensing lenslet 122b. Light is introduced into the specular reflective tube 114. The specular reflective cylinder 114 is composed of a highly reflective coating film applied to the outer peripheral surface of the cooling sleeve 113, and the semiconductor laser light introducing means 117 is formed of a dereflection coating film applied to the outer peripheral surface of the cooling sleeve 113 in a slit shape. It is configured. That is, the outer peripheral surface of the cooling sleeve 113 is covered with a highly reflective coating film as the specular reflective reflector 114 and a slit-like antireflection coating film as the semiconductor laser light introducing means 117.

  Reference numeral 121 denotes a stack type semiconductor laser configured by stacking a plurality of bar-shaped elements having a plurality of laser light emitting ends in the slow axis direction and stacked in the fast axis direction. It is arranged in parallel with the axial direction. Reference numerals 121-1 to 121-5 denote bar-shaped elements constituting the stack type semiconductor laser 121, 122 denotes a semiconductor laser beam condensing means for condensing the laser beam emitted from the stack type semiconductor laser, and 122-1 to 122-5. Is a cylindrical lens, which is opposed to each of the different bar-shaped elements 121-1 to 121-5 constituting the stacked semiconductor laser 121, and is disposed at a position substantially away from the opposing bar-shaped element by a focal length, The laser beam emitted from the opposing bar-like element is collimated. 122a integrates cylindrical lenses 122-1 to 122-5 in the direction parallel to the stacking direction of the bar-shaped elements 121-1 to 121-5 at the same interval as the stacking interval of the bar-shaped elements 121-1 to 121-5. The configured cylindrical lens array 122b is a direction (fast axis direction) parallel to the stacking direction of the bar-shaped elements 121-1 to 121-5 with the semiconductor laser light collimated by the cylindrical lenses 122-1 to 122-5. It is a condensing lenslet which condenses light. These stack type semiconductor laser 121, cylindrical lens array 122a and condensing lenslet 122b constitute a semiconductor laser light output device.

Next, the operation will be described.
The laser beams emitted from the bar-shaped elements 121-1 to 121-5 have a spreading angle of about 10 ° in the slow axis direction and a spreading angle of about 30 ° to 50 ° in the fast axis direction. The laser beams emitted from the bar-shaped elements 121-1 to 121-5 are mainly collimated in the component in the fast axis direction by the opposed cylindrical lenses 122-1 to 122-5. The collimated semiconductor laser light is condensed on the line by the condensing lenslet 122b. The collected semiconductor laser light is introduced into the specular reflective reflector 114 from the semiconductor laser light introducing means 117 constituted by the anti-reflection coating film located near the condensing position. The introduced semiconductor laser light enters the solid laser rod 112 and is partially absorbed. The remaining semiconductor laser light that has not been absorbed by the solid laser rod 112 is reflected by the specular reflecting reflector 114 made of a highly reflective coating film, and is incident on the solid laser rod 112 again and absorbed.

  Since the semiconductor laser light output device and the solid-state laser rod excitation module of Conventional Example 1 are configured as described above, a semiconductor laser 105 configured by integrating a plurality of laser light emission ends in the slow axis direction is used as a solid-state laser rod. In the semiconductor laser light output device composed of a semiconductor laser arranged so that the axial direction of 102 and the slow axis direction are parallel, the solid-state laser rod 102 side of the solid-state laser rod 102 can excite the solid-state laser rod 102 with high power. However, there was a problem that it was not suitable for high output.

  Further, the semiconductor laser light introduced into the diffusive reflector 104 by the semiconductor laser light introducing means 107 made of thin glass is first incident on the solid laser rod 102. For this reason, since the semiconductor laser light is incident on the portion of the solid laser rod 102 facing the end face of the semiconductor laser light introducing means 107 without attenuation of the intensity, the intensity distribution of the semiconductor laser light in the solid laser rod 102 is the semiconductor laser light. It becomes high on the introduction means 107 side. For this reason, the intensity distribution of the semiconductor laser light in the solid-state laser rod 102 is not axially symmetric and uniform, and the temperature distribution due to absorption of the semiconductor laser light in the solid-state laser rod 102 is deviated from the second-order axially symmetric distribution. There has been a problem that the laser rod 102 becomes a graded refraction index lens having wavefront aberration.

  Further, since the semiconductor laser light output device and the solid-state laser rod pumping module of the conventional example 2 are configured as described above, the solid-state laser rod pumping module 111 is moved from the semiconductor laser beam introducing means 117 into the specular reflecting reflector 114. Of the introduced semiconductor laser light, as shown in FIG. 22, the semiconductor laser light that is not incident on the solid laser rod 112 is geometrically applied to the solid laser rod 112 even if it is reflected by the specular reflection reflector 114 a plurality of times. Not incident. In FIG. 22, this state is indicated by an arrow indicated by a solid line. Therefore, in order to achieve high efficiency absorption of the semiconductor laser light by the solid-state laser rod 112 in the semiconductor laser light output device, the condensing angle at the condensing lenslet 122b is changed from the semiconductor laser light introducing means 117 to the solid-state laser rod 112. It is necessary to adjust the focal length of the condensing lenslet 122b so that it falls within the angle at which it is expected. As a result, the semiconductor laser light, which is uniquely determined by the focal length of the condensing lenslet 122b and focused on the line by the condensing lenslet 122b, is parallel to the stacking direction of the bar-shaped elements 121-1 to 121-5. The size of the direction (the direction perpendicular to the axial direction of the solid-state laser rod 112, the fast axis direction) (hereinafter sometimes referred to as the size of the condensing point of the semiconductor laser light) is obtained using the condensing lenslet 122b. There is a problem that the energy utilization efficiency of the semiconductor laser light is reduced, not the minimum size that can be achieved. As a result, the solid-state laser excitation module 111 has to increase the size of the semiconductor laser light introducing means 117, so that there is a problem that the confinement efficiency of the semiconductor laser light in the specular reflection reflector 114 is lowered. It was.

  It should be noted that the size of the condensing point of the semiconductor laser light is ideally that the size of the emission end of each laser light is d1, the focal length of each of the cylindrical lenses 122-1 to 122-5 is f1, and the condensing lens. When the focal length of the let 122b is f2, d1 × f2 / f1 is obtained, but actually, the variation in the stacking interval of the bar-shaped elements 121-1 to 121-5, the cylindrical lens 122 constituting the cylindrical lens array 122a. It further increases due to a pitch error of −1 to 122-5, an installation error of the bar-shaped elements 121-1 to 121-5, and the cylindrical lens array 122a.

  On the other hand, if the size of the semiconductor laser light introducing means 117 is reduced in order to increase the confinement efficiency of the semiconductor laser light in the specular reflecting reflector 114, the size of the condensing point of the semiconductor laser light becomes smaller. It becomes larger than the size of the means 117. For this reason, the ratio of the semiconductor laser light introduced into the specular reflective reflector 114 is lowered, and there is a problem that the semiconductor laser light cannot be efficiently absorbed by the solid laser rod 112. In the case of Conventional Example 2, the semiconductor laser light absorbed by the solid-state laser rod 112 out of the semiconductor laser light transmitted through the cylindrical lens array 122a was a very low value of 26%.

  Further, the semiconductor laser light introduced from the semiconductor laser light introducing means 117 into the specular reflecting reflector 114 first enters the solid laser rod 112. At this time, when the absorptance of the solid laser rod 112 is high, the intensity of the semiconductor laser light incident on the portion of the solid laser rod 112 facing the end surface of the semiconductor laser light introducing means 117 is reflected by the specular reflective reflector 114. The intensity distribution of the semiconductor laser light in the solid-state laser rod 112 is much higher than the intensity of the semiconductor laser light, and the intensity distribution of the semiconductor laser light in the solid-state laser rod 112 is high on the semiconductor laser light introducing means 117 side. Since it is not symmetrical and uniform, the temperature distribution generated by the absorption of the semiconductor laser light in the solid laser rod 112 deviates from the second-order axisymmetric distribution, and the solid laser rod 112 has a graded refraction with wavefront aberration. There was a problem of becoming an index lens.

  Further, the stack type semiconductor laser 121 used in the semiconductor laser light output device is composed of a plurality of bar-shaped elements 121-1 to 121-5 configured by integrating a plurality of laser light emitting ends in the slow axis direction. Are arranged so that the slow axis direction is parallel to the axial direction of the solid-state laser rod 112, so that the output laser light is perpendicular to the axial direction of the solid-state laser rod 112 ( Although it has a large spread angle in the fast axis direction), the spread angle is small in the direction parallel to the axial direction (slow axis direction). Therefore, the semiconductor laser light incident in the direction perpendicular to the axial direction of the solid-state laser rod 112 diffuses, but the semiconductor laser light having a small divergence angle in the direction parallel to the axial direction is the semiconductor laser light introducing means of the solid-state laser rod 112. There was a problem that the portion facing the end face of 117 would be concentrated and excited.

  Further, in the above semiconductor laser light output device, when the laser light is condensed by another semiconductor laser light condensing means such as an aspherical lens instead of the condensing lenslet 122b, the semiconductor laser light separated by an arbitrary distance. Depending on the size in the slow axis direction, the laser beam may spread beyond the size of the aspherical lens and not all the laser beam may be incident, which reduces the energy utilization efficiency of the semiconductor laser beam. .

  The present invention was made to solve the above-described problems, and a semiconductor laser light output device capable of obtaining a small and highly efficient laser light synthesized with high density using a semiconductor laser light, and An object of the present invention is to obtain a solid-state laser rod pumping module capable of pumping a solid-state laser rod with high power and high efficiency using semiconductor laser light and obtaining laser light with high beam quality.

A solid-state laser rod excitation module according to the present invention includes a cylindrical cooling sleeve disposed so as to surround a solid-state laser rod substantially coaxially with the solid-state laser rod, and surrounds the solid-state laser rod and the cooling sleeve substantially coaxially with the solid-state laser rod. A cylindrical diffusive reflecting cylinder, and a semiconductor laser beam output that outputs laser light toward the diffusive reflecting cylinder so that the axial direction of the solid laser rod and the fast axis direction of the semiconductor laser are parallel to each other Semiconductor laser light introduction that is provided in the device and the diffusive reflector, and that introduces the laser light emitted from the semiconductor laser output device toward the solid laser rod of the diffusive reflector while maintaining the size in the fast axis direction substantially The semiconductor laser beam output device is a bar-shaped element configured by integrating a plurality of laser beam emission ends in the slow axis direction. An array semiconductor laser, a first semiconductor laser light refracting means that refracts laser light emitted from the array semiconductor laser in the fast axis direction of the array semiconductor laser, and a front stage or a rear stage of the first semiconductor laser light refracting means. The second semiconductor laser beam refracting means for refracting the laser light emitted from the array semiconductor laser in the slow axis direction of the array semiconductor laser, and the second semiconductor, which is a stage preceding or following the first semiconductor laser beam refracting means A semiconductor laser beam condensing unit provided before or after the laser beam refracting unit and condensing the laser beam emitted from the array semiconductor laser in the fast axis direction and the slow axis direction of the array type semiconductor laser; It is provided.

A solid-state laser rod excitation module according to the present invention includes a cylindrical cooling sleeve disposed so as to surround a solid-state laser rod substantially coaxially with the solid-state laser rod, and surrounds the solid-state laser rod and the cooling sleeve substantially coaxially with the solid-state laser rod. A cylindrical diffusive reflecting cylinder, and a semiconductor laser beam output that outputs laser light toward the diffusive reflecting cylinder so that the axial direction of the solid laser rod and the fast axis direction of the semiconductor laser are parallel to each other Semiconductor laser light introduction that is provided in the device and the diffusive reflector, and that introduces the laser light emitted from the semiconductor laser output device toward the solid laser rod of the diffusive reflector while maintaining the size in the fast axis direction substantially The semiconductor laser beam output device includes a bar-shaped element formed by integrating a plurality of laser beam emission ends in the slow axis direction. A stack type semiconductor laser constructed by laminating a plurality of layers in the direction of the strike axis, a first semiconductor laser beam refracting means for refracting laser light emitted from the stack type semiconductor laser in the fast axis direction of the stack type semiconductor laser, A second semiconductor laser light refracting means which is provided before or after the semiconductor laser light refracting means and refracts laser light emitted from the stack type semiconductor laser in the slow axis direction of the stack type semiconductor laser; The laser beam emitted from the stack type semiconductor laser is condensed in the fast axis direction of the stack type semiconductor laser, which is provided before or after the laser beam refracting means and before or after the second semiconductor laser light refracting means. And a semiconductor laser beam condensing means for condensing in the slow axis direction.

A solid-state laser rod excitation module according to the present invention includes a cylindrical cooling sleeve disposed so as to surround a solid-state laser rod substantially coaxially with the solid-state laser rod, and surrounds the solid-state laser rod and the cooling sleeve substantially coaxially with the solid-state laser rod. The arranged cylindrical specular reflective cylinder and the semiconductor which outputs laser light toward the specular reflective cylinder and is arranged so that the axial direction of the solid laser rod and the fast axis direction of the semiconductor laser are parallel to each other Laser light output device and mirror-reflective reflecting cylinder are provided, and the laser light emitted from the semiconductor laser output device is introduced toward the solid laser rod of the specular reflecting reflecting tube while maintaining the size in the fast axis direction. And a semiconductor laser beam output device, wherein a plurality of laser beam emission ends are integrated in the slow axis direction. An array semiconductor laser, which is a bar-shaped element, a first semiconductor laser light refracting means for refracting laser light emitted from the array semiconductor laser in the fast axis direction of the array semiconductor laser, and a first semiconductor laser light refracting means A second semiconductor laser light refracting means provided at the front stage or the rear stage and refracting the laser light emitted from the array semiconductor laser in the slow axis direction of the array semiconductor laser; A semiconductor laser which is provided before or after the second semiconductor laser beam refracting means and focuses the laser beam emitted from the array semiconductor laser in the fast axis direction and the slow axis direction of the array type semiconductor laser. And a light condensing means.

A solid-state laser rod excitation module according to the present invention includes a cylindrical cooling sleeve disposed so as to surround a solid-state laser rod substantially coaxially with the solid-state laser rod, and surrounds the solid-state laser rod and the cooling sleeve substantially coaxially with the solid-state laser rod. The arranged cylindrical specular reflective cylinder and the semiconductor which outputs laser light toward the specular reflective cylinder and is arranged so that the axial direction of the solid laser rod and the fast axis direction of the semiconductor laser are parallel to each other Laser light output device and mirror-reflective reflecting cylinder are provided, and the laser light emitted from the semiconductor laser output device is introduced toward the solid laser rod of the specular reflecting reflecting tube while maintaining the size in the fast axis direction. And a semiconductor laser beam output device, wherein a plurality of laser beam emission ends are integrated in the slow axis direction. Stack type semiconductor laser comprising a plurality of stacked bar-shaped elements stacked in the fast axis direction, and first semiconductor laser beam refraction for refracting laser light emitted from the stack type semiconductor laser in the fast axis direction of the stack type semiconductor laser And a second semiconductor laser light refracting means provided in the front stage or the rear stage of the first semiconductor laser light refracting means and refracting the laser light emitted from the stack type semiconductor laser in the slow axis direction of the stack type semiconductor laser. The laser beam emitted from the stack type semiconductor laser is provided before or after the first semiconductor laser beam refracting means and before or after the second semiconductor laser beam refracting means. And a semiconductor laser beam condensing means for condensing in the direction and concentrating in the slow axis direction.

In the solid-state laser rod excitation module according to the present invention, the second semiconductor laser beam refracting means is a roof prism, and the ridge line of the roof prism is parallel to the fast axis direction of the semiconductor laser. The surface facing the ridge line is set substantially perpendicular to the traveling direction of the semiconductor laser light.

In the solid laser rod excitation module according to the present invention, the second semiconductor laser beam refracting means is a prism having a trapezoidal cross section obtained by cutting the ridge line portion of the roof prism in a plane parallel to the surface facing the ridge line of the roof prism. The imaginary ridgeline of this prismatic prism roof type prism is in a direction parallel to the fast axis direction, and the surface facing the imaginary ridgeline of the prismatic prism roof type prism is approximately the traveling direction of the semiconductor laser light. It is installed vertically.

  The solid-state laser rod excitation module according to the present invention includes a slit in which a semiconductor laser light introduction means is formed in a diffusive reflector, a hexahedral slab waveguide disposed in the slit, and six end faces of the slab waveguide. A first end face on which laser light enters and four end faces other than the second end face on which laser light exits are provided in a gap between the slit and an adhesive layer having a refractive index smaller than that of the slab waveguide. It is what.

  In the solid-state laser rod excitation module according to the present invention, the semiconductor laser beam introducing means has a second end face area smaller than the first end face area and is perpendicular to the axial direction of the solid laser rod on the second end face. The length in the direction is larger than the diameter of the solid laser rod.

  The solid-state laser rod excitation module according to the present invention is characterized in that the number of times that the semiconductor laser light incident by the semiconductor laser light introducing means reflects the end face in the direction perpendicular to the fast axis direction of the semiconductor laser is at most once. Is.

  The solid-state laser rod excitation module according to the present invention includes a semiconductor laser light diffusion means for diffusing the laser light introduced by the semiconductor laser light introduction means between the semiconductor laser light introduction means and the solid-state laser rod. It is what.

  The solid-state laser rod excitation module according to the present invention is characterized in that the semiconductor laser light diffusing means is made of a transparent optical material whose surface is roughened like a ground glass.

  The solid laser rod excitation module according to the present invention is characterized in that the semiconductor laser light diffusion means is made of a transparent foamable glass material containing bubbles.

  The solid-state laser rod excitation module according to the present invention is characterized in that the semiconductor laser light diffusion means is formed on the cooling sleeve.

  The solid-state laser rod excitation module according to the present invention is characterized in that the semiconductor laser light diffusion means is made of sapphire.

According to the present invention, there is an effect that the solid laser rod can be excited with high power and high efficiency, and laser beam with high beam quality can be obtained.
Further, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and further, the apparatus itself can be miniaturized.

According to the present invention, there is an effect that the solid laser rod can be excited with high power and high efficiency, and laser beam with high beam quality can be obtained.
Further, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and further, the apparatus itself can be miniaturized.

According to the present invention, there is an effect that the solid laser rod can be excited with high power and high efficiency to obtain high-power laser light.
Further, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and further, the apparatus itself can be miniaturized.

According to the present invention, there is an effect that the solid laser rod can be excited with high power and high efficiency to obtain high-power laser light.
Further, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and further, the apparatus itself can be miniaturized.

According to the present invention, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and to further reduce the size of the apparatus itself.

According to the present invention, it is possible to obtain a laser beam obtained by synthesizing power with high density using a semiconductor laser beam with high efficiency, and to further reduce the size of the apparatus itself.

  According to this invention, the laser light is incident on the slit formed in the diffusive reflecting cylinder of the semiconductor laser light introduction means, the hexahedral slab waveguide disposed in the slit, and the six end faces of the slab waveguide. Since the first end face and the four end faces other than the second end face from which the laser beam is emitted are provided in the gap between the slit and the adhesive layer having a refractive index smaller than that of the slab waveguide, the configuration is simplified. There is an effect that can.

  According to this invention, the semiconductor laser light introducing means has a second end face area smaller than the first end face area and a length in the direction perpendicular to the axial direction of the solid laser rod on the second end face. Since it is larger than the diameter of the solid laser rod, there is an effect that the solid laser rod can be excited with high efficiency without exciting the solid laser rod only from the biased direction.

  According to the present invention, the number of times that the semiconductor laser light incident by the semiconductor laser light introducing means reflects the end face in the direction perpendicular to the fast axis direction of the semiconductor laser is at most once. The laser beam confinement efficiency of the introducing means can be improved, and the solid laser rod can be excited with high efficiency.

According to the present invention, there is an effect that a solid laser rod can be excited with high power and high efficiency to obtain laser light with high beam quality.

According to the present invention, there is an effect that a solid laser rod can be excited with high power and high efficiency to obtain laser light with high beam quality.

According to the present invention, there is an effect that a solid laser rod can be excited with high power and high efficiency to obtain laser light with high beam quality.

According to this invention, there exists an effect which can simplify a structure.

According to the present invention, there is an effect that the mechanical strength of the semiconductor laser light diffusing means is increased.

An embodiment of the present invention will be described below.
Embodiment 1 FIG.
1 is a cross-sectional view showing a configuration of a solid-state laser rod excitation module according to Embodiment 1 of the present invention. 1B is a cross-sectional view taken along line AA in FIG. 1A, and FIG. 1C is an enlarged view of a portion B in FIG. 1A. 1A to 1C, 1 is a solid-state laser rod excitation module, 2 is a solid-state laser rod, and 3 is a cooling sleeve, which is transparent to semiconductor laser light and has a cylindrical shape. The solid laser rod 2 is disposed so as to be substantially coaxial with the solid laser rod 2. In addition, a coolant for cooling the solid laser rod 2 is circulated inside. Reference numeral 4 denotes a cylindrical diffusive reflecting cylinder that is diffusible with respect to the semiconductor laser light, and is disposed substantially coaxially with the solid laser rod 2 so as to surround the solid laser rod 2 and the cooling sleeve 3. Reference numerals 5-1 to 5-5 denote bar-shaped elements constituting the stacked semiconductor laser 5. The stack type semiconductor laser 5 is configured by laminating a plurality of bar-shaped elements configured by integrating a plurality of laser light emitting ends in the slow axis direction in the fast axis direction. Further, the stack type semiconductor laser 5 is arranged so that the direction perpendicular to the axial direction of the solid-state laser rod 2 and the slow axis direction are parallel, and the axial direction of the solid-state laser rod 2 and the fast axis direction are parallel. The laser beams emitted from the bar-shaped elements 5-1 to 5-5 have a spread angle of about 10 ° in the direction perpendicular to the axial direction of the solid laser rod 2, but are as large as about 30 ° in the parallel direction. Has a spread angle.

  Reference numeral 6 denotes a semiconductor laser beam condensing means for condensing the laser beam emitted from the stack type semiconductor laser 5. Reference numerals 6-1 to 6-5 denote cylindrical lenses, which are opposed to different bar-shaped elements constituting the stack type semiconductor laser 5, and are arranged at positions substantially away from the opposed bar-shaped elements by the approximate focal length. The laser beams emitted from the opposing bar-like elements are collimated. Reference numeral 6a denotes a cylindrical lens array, which includes cylindrical lenses 6-1 to 6-5. Reference numeral 6b denotes an aspherical lens. The aspherical lens 6b and the cylindrical lens array 6a constitute a semiconductor laser beam condensing means 6. The stack type semiconductor laser 5 and the semiconductor laser beam condensing means 6 constitute a semiconductor laser beam output device 5a. 7 is a semiconductor laser light introducing means provided in the diffusive reflecting cylinder 4, and the semiconductor laser light condensed by the semiconductor laser light condensing means 6 is directed toward the solid laser rod 2 in the diffusive reflecting cylinder 4. Introduce. Reference numeral 8 denotes a semiconductor laser light diffusion means provided on the surface of the cooling sleeve 3, which diffuses the semiconductor laser light introduced by the semiconductor laser light introduction means 7. In FIG. 1A, an arrow X indicates a direction perpendicular to the axial direction of the solid-state laser rod 2, and in FIG. 1B, an arrow Y indicates a direction parallel to the axial direction of the solid-state laser rod 2. FIG. 1B shows a state in which the coolant flows.

  FIG. 1 shows a case where five bar-shaped elements and five cylindrical lenses are provided, but there may be five or more. FIG. 1 illustrates the case where each of the stack type semiconductor laser 5, the semiconductor laser light condensing means 6, and the semiconductor laser light introducing means 7 is provided, but the same in the axial direction of the solid-state laser rod 2. There may be a plurality of components.

  Hereinafter, the semiconductor laser light output device 5a, the semiconductor laser light introducing means 7, and the semiconductor laser light diffusing means 8 will be described in detail, and then the operation of the solid-state laser rod excitation module 1 will be described.

1. Semiconductor laser beam output device (a) Stack type semiconductor laser In the example shown in the drawing, the stack type semiconductor laser 5 is a bar-shaped element constructed by integrating a plurality of laser beam emission ends in the slow axis direction. A plurality of layers are stacked in the axial direction. Further, the stack type semiconductor laser 5 is arranged so that the direction perpendicular to the axial direction of the solid-state laser rod 2 and the slow axis direction are parallel, and the axial direction of the solid-state laser rod 2 and the fast axis direction are parallel. The laser beams emitted from the bar-shaped elements 5-1 to 5-5 have a spread angle of about 10 ° in the direction perpendicular to the axial direction of the solid laser rod 2, but are as large as about 30 ° in the parallel direction. Has a spread angle.

(B) Semiconductor Laser Light Condensing Means The semiconductor laser light condensing means 6 condenses the laser light emitted from the stack type semiconductor laser 5 in order to increase the output. Further, by reducing the size of the semiconductor laser light introducing means 7, the escape of the semiconductor laser light from the diffusive reflector 4 is reduced, so that all the semiconductor laser light can be incident on the semiconductor laser light. It is necessary to reduce the size of the condensing point.

  In the first embodiment, the semiconductor laser beam condensing means 6 is composed of a cylindrical lens array 6a and an aspheric lens 6b. The cylindrical lens array 6a is configured such that the cylindrical lenses 6-1 to 6-5 are parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 at the same interval as the stacking interval of the bar-shaped elements 5-1 to 5-5. (A direction parallel to the axial direction of the solid-state laser rod 2 and a fast axis direction). Each cylindrical lens 6-1 to 6-5 is opposed to a different bar-shaped element 5-1 to 5-5 constituting the stacked semiconductor laser 5, and each cylindrical lens 6-1 to 6-6 is formed from the opposed bar-shaped element. It is arranged at a position separated by a substantially focal length of −5. The aspherical lens 6b has a refractive power in a direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5, and is between the cylindrical lens array 6a and the semiconductor laser light introducing means 7, and is a semiconductor laser. The light introducing means 7 is disposed at a position separated by the focal length of the aspherical lens 6b.

  When the semiconductor laser beam condensing means 6 is configured as described above, the laser beams emitted from the opposing bar-shaped elements are collimated by the cylindrical lenses 6-1 to 6-5. The semiconductor laser beams collimated by the respective cylindrical lenses 6-1 to 6-5 are condensed on a line in a direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 by the aspherical lens 6b. The size of the semiconductor laser light focused on the line by the aspherical lens 6b (in the fast axis direction) parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (that is, the size of the condensing point) ) Ideally, when the size of the emission end of each laser beam is d2, the focal length of each of the cylindrical lenses 6-1 to 6-5 is f3, and the focal length of the aspherical lens 6b is f, d2 × f / f3, which is very small, for example, several μm.

  In this case, the width of the semiconductor laser light that has passed through the cylindrical lens array 6a in the direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (fast axis direction) is as large as 10 to 20 mm, for example. Since the condensing angle at the lens becomes large, spherical aberration occurs and the size of the condensing point is greatly blurred. However, by using the aspherical lens 6b as the condensing lens, the spherical aberration can be suppressed low, and the size of the condensing point. Is kept small.

  In this case, when any of the bar-shaped elements 5-1 to 5-5 is deviated from the predetermined installation position, the laser beam emitted from the bar-shaped element deviated from the predetermined installation position is paralleled by the opposing cylindrical lens. When the laser beam is converted into an angle, an angle deviation from a predetermined direction occurs in the parallelized semiconductor laser beam. For example, FIG. 2 shows that the bar-shaped element 5-1 is shifted by Δp from a predetermined installation position (the bar-shaped element 5-1 though the predetermined stacking interval of the bar-shaped elements 5-1 to 5-5 is p. 1 and the adjacent bar-like element 5-2 is p + Δp), the semiconductor laser beam collimated by the opposing cylindrical lens 6-1 causes an angular deviation θ (unit: radians) from a predetermined direction. Shows the case. At this time, the condensing position of the collimated semiconductor laser light having the angular deviation θ1 by the aspherical lens 6b is parallel to the stacking direction of the bar-shaped elements 5-1 to 5-n from the predetermined condensing position O. Is shifted by f × θ1 (1f is the focal length of the aspherical lens 6b).

  In order to reduce the deviation from the predetermined condensing position O and reduce the size of the condensing point, the focal length f of the aspherical lens 6b may be reduced. Coma aberration occurs in the semiconductor laser light passing through a position away from the center position of the spherical lens 6b, and the size of the condensing point is greatly blurred. FIG. 3 shows the width of the semiconductor laser light passing through the cylindrical lens array 6a in the direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (the direction parallel to the axial direction of the solid laser rod 2 and the fast axis direction). The aspherical lens 6b normalized by L passes through a cylindrical lens array 6a having the focal length f of the aspherical lens 6b as a horizontal axis and having a spread angle of ± θ in a direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5. It is the graph which showed the magnitude | size of the condensing point when a semiconductor laser beam was condensed on the line by the aspherical lens 6b as a vertical axis | shaft. The values shown in FIG. 3 are results obtained by calculating the aspherical shape of the aspherical lens 6b so that the size of the condensing point at each focal length is minimized. In FIG. 3, a curve a is a case where coma occurs, and a straight line b is a case where no coma occurs. As shown in FIG. 3, when coma does not occur, the focal length is reduced and the size of the focal point is reduced. On the other hand, when coma occurs, it becomes minimum when the focal length f of the aspherical lens 6b normalized by the width L is 0.7, and becomes extremely large when it is smaller than 0.5. Accordingly, when the focal length f of the aspheric lens 6b normalized by the width L is 0.5 or more, that is, when the focal length f of the aspheric lens is 0.5 × L or more, the size of the condensing point is large. This is desirable because of its small size.

  In the case where an angle shift occurs from a predetermined installation position in which the cylindrical lens array 6a and the aspherical lens 6b are arranged in parallel with the AA line shown in FIG. Aspherical lens 6b for semiconductor laser light in a direction (fast axis direction) parallel to the stacking direction of bar-shaped elements 5-1 to 5-5 at two points separated by a predetermined interval in a direction parallel to the axial direction of The condensing position shifts due to the above, and the focal point is incident on the semiconductor laser light introducing means 7 in a blurred manner. For example, when an angle shift of 1 ° occurs, the shift of the condensing position is 170 μm at two points 10 mm apart. Therefore, as shown in FIG. 4, when the aspherical synthetic lens 6c in which the cylindrical lens array and the aspherical lens are integrally formed is used, the angle deviation can be suppressed to 0.1 ° or less, and the condensing position This is desirable because the deviation is small.

  Further, when an aspherical lens having refractive power in a direction (slow axis direction) perpendicular to the stacking direction of the bar-shaped elements 5-1 to 5-5 is used, each cylindrical lens 6-1 to 6-5 is used. The semiconductor laser beam collimated by the above is condensed on the line in a direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 by the aspherical lens 6b and also in the vertical direction. Therefore, when the aspherical lens 6b having refractive power in the direction perpendicular to the stacking direction of the bar-shaped elements 5-1 to 5-5 is used, the size of the semiconductor laser light introducing means 7 can be reduced. Since the escape of the semiconductor laser light from the diffusive reflector 4 is reduced, it is desirable that the solid laser rod 2 can be excited more efficiently.

2. Semiconductor laser light introducing means The semiconductor laser light introducing means 7 converts the semiconductor laser light condensed by the semiconductor laser light condensing means 6 into a bar-shaped element 5-1, in order to excite the solid laser rod 2 with high efficiency. It is introduced toward the solid-state laser rod 2 in the diffusive reflector 4 while substantially maintaining the size (fast axis direction) parallel to the stacking direction of ˜5-5.

  The size of the semiconductor laser light focused on the line by the aspherical lens 6b in the direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (fast axis direction), that is, in the axial direction of the solid-state laser rod 2. The size in the parallel direction is the smallest at the condensing position by the aspherical lens 6b, but divergently increases before and after that. Further, when the diffusive reflector 4 is formed of a ceramic material or a polymer material generally used as a material for forming the diffusive reflector 4, the reflectance greatly depends on the thickness of the diffusive reflector 4. For example, when the diffusive reflector 4 having a reflectance of 98% or more is formed of a ceramic material, the thickness of the diffusive reflector 4 needs to be about 10 mm.

  For this reason, as shown in FIG. 5, when the semiconductor laser light introducing means 7 is composed of only the slits 11 formed in the diffusive reflector 4, the bar-like elements 5-1 to 5-5 of the slits 11 are used. The size in the direction parallel to the stacking direction (direction parallel to the axial direction of the solid-state laser rod 2 and fast axis direction) must be increased. For example, the thickness L of the diffusive reflecting cylinder 4 is 10 mm, the width L parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 of the semiconductor laser light passing through the cylindrical lens array 6a is 10 mm, and the aspherical lens 6b When the focal length is 7 mm, the spread angle of the semiconductor laser light before and after the converging position by the aspherical lens 6b is about 70 °, and the bar-shaped elements 5-1 to 5-5 of the semiconductor laser light at both ends of the slit 11 The size in the direction parallel to the laminating direction is 7 mm. Therefore, the confinement performance of the semiconductor laser light in the diffusive reflector 4 is lowered. As a result, the semiconductor laser light introducing means 7 for introducing the semiconductor laser light into the diffusive reflector 4 while maintaining the size at the condensing point in the direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5. Is required.

  As shown in FIG. 6, in the first embodiment, the semiconductor laser light introducing means 7 includes a slit 11 formed in the diffusive reflector 4, a hexahedral slab waveguide 12 disposed in the slit 11, and a slab guide. From the slab waveguide 12 provided in the gap between the slits 11 and the four end faces other than the first end face 12a on which the semiconductor laser light is incident and the second end face 12b on which the semiconductor laser light is emitted among the six end faces of the waveguide 12 The adhesive layer 13 is made of an optical adhesive having a small refractive index. FIG. 6B is a cross-sectional view taken along line BB in FIG.

  When the semiconductor laser light introducing means 7 is configured in this way, the semiconductor laser light condensed on the line at the condensing position O enters the slab waveguide 12 from the first end face 12a. The semiconductor laser light incident on the slab waveguide 12 repeats total reflection at the interface between the adhesive layer 13 having a lower refractive index than that of the slab waveguide 12 and the slab waveguide 12, and is emitted from the second end face 12b. It is introduced into the reflecting cylinder 4.

  Here, the stack type semiconductor laser 5 in the present invention has a bar-like element configured by integrating a plurality of laser light emitting ends in a direction perpendicular to the axial direction of the solid-state laser rod 2, and the axial direction of the solid-state laser rod 2. Since a plurality of layers are stacked in the parallel direction (fast axis direction), the semiconductor laser light in the direction parallel to the axial direction of the solid-state laser rod 2 has a large spread angle. For this reason, the axial direction of the solid-state laser rod 2 is different from that in the case where the axial direction of the solid-state laser rod 2 is parallel to the fast axis direction and the axial direction of the solid-state laser rod 2 is perpendicular to the slow axis direction. Of the semiconductor laser light incident from a direction parallel to the direction, the ratio of the amount of light initially incident on the portion facing the second end face 12b of the solid-state laser rod 2 is much smaller. Further, as shown in FIG. 6A, the length W of the second end face 12b in the direction perpendicular to the axial direction of the solid laser rod 2 is configured to be larger than the diameter R of the solid laser rod 2. In addition, the ratio of the amount of light incident on the solid laser rod 2 at the beginning of the semiconductor laser light incident on the solid laser rod 2 from a direction parallel to the cross-sectional plane of FIG. In FIG. 6, this state is indicated by arrows.

  The slab waveguide 12 may have a rectangular parallelepiped shape as shown in FIG. 6 as long as the area of the second end face 12b is smaller than the area of the first end face 12a of the slab waveguide 12 as shown in FIG. This is desirable because the escape of the semiconductor laser light from the semiconductor laser light introducing means 7 can be reduced and the solid laser rod 2 can be excited with high efficiency. At this time, if the length W of the second end face 12b of the slab waveguide 12 in the direction perpendicular to the axial direction of the solid laser rod 2 is made larger than the diameter R of the solid laser rod 2 as described above, The ratio of the amount of light incident on the solid laser rod 2 at the beginning of the semiconductor laser light emitted from the second end face 12b can be reduced. Thereby, the non-uniform distribution of the excitation intensity of the solid laser rod 2 can be eliminated, the solid laser rod 2 can be excited with high power and high efficiency, and laser light with high beam quality can be obtained. It is also desirable to increase the refractive index of the slab waveguide 12 as much as possible and to reduce the critical angle of the total reflection condition as much as possible. Note that FIG. 7B is a cross-sectional view taken along the line BB in FIG.

However, if the area of the second end face 12b is made too small compared to the area of the first end face 12a, the incident angle of the semiconductor laser light on the end face of the slab waveguide 12 becomes small and the total reflection condition may not be satisfied. Therefore, it is necessary to set the sizes of the first and second end faces 12a and 12b in consideration of this. Here, as shown in FIG. 8, in the slab waveguide 12, the size in the slow axis direction of the first end face 12a where the semiconductor laser light is incident is a, and the slow speed in the second end face 12b where the semiconductor laser light is emitted. The length in the longitudinal direction of the slab waveguide 12 that is b in the axial direction, the direction perpendicular to the slow axis direction and the fast axis direction is c, and the slab waveguide 12 of the third and fourth end faces 12c and 12d. Is defined as α (= tan [(a−b) / 2c]. In the semiconductor laser light incident on the slab waveguide 12, the spot size is defined as ka and the spreading half angle is defined as i. the semiconductor laser light beam slab waveguide 12 within in the third, fourth end surface 12c, assuming the number of reflections n for 12d, the incident angle _{i n (n = 1,2, ...} ) at each reflection and Each Angle beta _n of the longitudinal axis of the slab waveguide 12 in the beam (n = 1,2, ...), the following equation (1), the relationship of Equation (2) holds.

Here, n ₁ is the refractive index of the adhesive layer 13, n ₂ is the refractive index of the slab waveguide 12, and γ is the emission angle of the semiconductor laser light into the slab waveguide 12. From the above formulas (1) and (2), the conditions are limited in the slab waveguide 12 under the condition that the semiconductor laser light is totally reflected in the slab waveguide 12 and the condition that the semiconductor laser light is totally transmitted from the slab waveguide 12. The relationship of the number of reflections is obtained as in the following formulas (3) and (4).

FIG. 9 shows an equation in the case where the slab waveguide 12 is formed by BK7 (n ₂ = 1.516) or YAG (n ₂ = 1.82) with the spread angle of the semiconductor laser light in the slow axis direction being 10 °. The relationship between the inclination angle α from the longitudinal axis direction of the slab waveguide 12 obtained from (3) and formula (4) and the number of reflections limited in the slab waveguide 12 is shown.

  As shown in FIG. 9, a direction perpendicular to the slow axis direction and the fast axis direction by increasing the inclination angle α from the longitudinal axis direction of the slab waveguide 12 as much as possible from the conditions obtained from the equations (3) and (4). In order to shorten the length c of the slab waveguide 12 in the longitudinal axis direction, the number of reflections of the semiconductor laser light in the slab waveguide 12 in the direction perpendicular to the fast axis direction is at most one (that is, FIG. 7). It is necessary to emit from the slab waveguide 12 as the number of reflections with respect to the third and fourth end faces 12c and 12d in the slab waveguide 12 shown in FIG. Further, by increasing the refractive index n2 of the slab waveguide 12, the inclination angle α from the longitudinal axis direction of the slab waveguide 12 can be increased, so that the area of the first end face 12a of the slab waveguide 12 is larger. If the area of the second end face 12b is small, the escape of the semiconductor laser light from the semiconductor laser light introducing means 7 can be reduced, and the solid laser rod 2 can be excited with high efficiency.

3. Semiconductor laser light diffusing means The component in the direction parallel to the axial direction of the solid laser rod 2 (fast axis direction) in the semiconductor laser light incident into the diffusive reflector 4 is diffused. The ratio of the incident semiconductor laser light is small. On the other hand, since the semiconductor laser light having a component perpendicular to the axial direction of the solid-state laser rod 2 (slow axis direction) has a small divergence angle, the area of the first end face 12a in the slab waveguide 12 is reduced to the second as described above. By making the length W of the second end surface 12b perpendicular to the axial direction of the solid laser rod 2 larger than the diameter R of the solid laser rod 2, the solid laser rod 2 is first Although the ratio of the incident semiconductor laser light can be reduced, the uneven distribution of the excitation intensity of the solid-state laser rod 2 cannot be completely eliminated.

  FIG. 10 schematically shows the propagation of the semiconductor laser light in the diffusive reflector 4. As shown in the figure, since the semiconductor laser light emitted from the semiconductor laser light introducing means 7 has directivity, it passes through the transparent cooling sleeve 3 to the semiconductor laser light introducing means 7 side of the solid laser rod 2. Incident with strong light intensity. Thereafter, the remaining weak semiconductor laser light absorbed by the solid-state laser rod 2 is diffusely reflected by the diffusive reflector 4 to reduce the directivity, and is further reduced in intensity and re-incident on the solid-state laser rod 2. . The semiconductor laser light once diffusely reflected is uniformly distributed in the diffusive reflector 4 and the solid laser rod 2 is uniformly irradiated with the semiconductor laser light from the substantially cylindrical diffusive reflector 4. . However, since this irradiation light intensity is small, a portion of the solid laser rod 2 facing the end face of the semiconductor laser light introducing means 7 shows a high intensity distribution, and a uniform distribution cannot be obtained.

  In order to avoid this problem, it is effective to reduce the directivity of the semiconductor laser light before the light emitted from the semiconductor laser light introducing means 7 enters the solid laser rod 2. Therefore, as shown in FIG. 11, a semiconductor laser light diffusion means 8 is provided to diffuse the semiconductor laser light introduced by the semiconductor laser light introduction means 7 between the semiconductor laser light introduction means 7 and the solid-state laser rod 2. .

  The semiconductor laser light diffusing means 8 can be configured by arranging a transparent glass-like optical material surrounding the solid laser rod 2, but in the first embodiment, the inner peripheral surface of the cooling sleeve 3 is a ground rough. The semiconductor laser light diffusing means 8 is configured by roughening in a ground glass shape. In this case, the surface roughness of the ground rough depends on the refractive index of the cooling sleeve 3, but is preferably several times to 10 times the wavelength of the semiconductor laser light, that is, about several μm to 10 μm. Moreover, although there are methods such as mechanical polishing and chemical treatment as a method for forming a ground rough, it is desirable to use chemical treatment because cracks and the like can be suppressed. Even with the same surface roughness, the larger the difference in the refractive index at the boundary, the higher the diffusibility. Therefore, it is desirable that the material of the semiconductor laser light diffusing means 8 has a high refractive index. Since the cooling sleeve 3 is desired to be thin and have high mechanical strength, when the semiconductor laser light diffusing means 8 is formed on the cooling sleeve 3, it is suitable to form it by sapphire.

  The semiconductor laser light diffusing means 8 formed on the inner peripheral surface of the cooling sleeve 3 diffuses the directional high-intensity semiconductor laser light introduced into the diffusive reflector 4. In FIG. 11, this state is indicated by arrows. The diffused semiconductor laser light is uniformly distributed in the diffusive reflector 4 and is incident on the solid laser rod 2 and absorbed. For this reason, the intensity distribution of the semiconductor laser light in the solid laser rod 2 becomes axisymmetric and uniform, and the temperature distribution in the solid laser rod 2 becomes a second-order axisymmetric distribution, and the solid laser rod 2 has wavefront aberration. No graded / refractive index lens, and high beam quality laser light can be obtained.

  When the cooling sleeve 3 is used as the semiconductor laser light diffusing means 8, the cooling sleeve 3 may be made of foamable glass containing bubbles having a diameter of several to about 10 times the wavelength of the semiconductor laser light, that is, about several μm to 10 μm. it can. In this case, the diffusibility is higher than when the inner peripheral surface of the cooling sleeve 3 is a ground rough.

Next, the operation will be described.
The laser beams emitted from the bar-shaped elements 5-1 to 5-5 are collimated by the opposed cylindrical lenses 6-1 to 6-5. The collimated semiconductor laser beam is lined in a direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (direction parallel to the axial direction of the solid-state laser rod 2, fast axis direction) by the aspherical lens 6b. Focused. The semiconductor laser light focused on the line enters the slab waveguide 12 from the first end face 12a. The semiconductor laser light incident on the slab waveguide 12 repeats total reflection at the end face of the slab waveguide 12, exits from the second end face 12 b, and is introduced into the diffusive reflector 4.

  At this time, the laser light emitted from each of the bar-shaped elements 5-1 to 5-5 of the stack type semiconductor laser 5 has a spread angle of about 10 ° in a direction (slow axis direction) perpendicular to the axial direction of the solid-state laser rod 2. And has a spread angle of about 30 ° in the direction parallel to the axial direction of the solid-state laser rod 2 (fast axis direction). For this reason, the semiconductor laser light incident in the direction parallel to the axial direction of the solid-state laser rod 2 is diffused, and the amount of the semiconductor laser light incident on the portion of the solid-state laser rod 2 facing the end surface of the semiconductor laser light introducing means 7 is reduced. The ratio is a small value. Further, the area of the first end face 12a in the slab waveguide 12 is made larger than that of the second end face 12b, and the length W of the second end face 12b in the direction perpendicular to the solid laser rod biaxial direction is set as the solid laser rod. 2 is larger than the diameter R of the semiconductor laser beam 2 as shown in FIG. 1A, the semiconductor laser light incident in the direction perpendicular to the axial direction of the solid laser rod 2 having a small divergence angle is first applied to the solid laser rod 2. The ratio of the amount of light incident on the is reduced. Further, as shown in FIG. 1C, the incident semiconductor laser light is diffused by the semiconductor laser light diffusion means 8 provided on the inner peripheral surface of the cooling sleeve 3. As described above, the semiconductor laser light is uniformly distributed in the diffusive reflector 4.

  As described above, according to the first embodiment, the solid-state laser rod excitation module 1 includes the solid-state laser rod 2, the cooling sleeve 3, the diffusive reflector 4, the stacked semiconductor laser 5 and the semiconductor laser described above. Since the semiconductor laser light output device 5a composed of the light condensing means 6, the semiconductor laser light introducing means 7, and the semiconductor laser light diffusing means 8 are used, the solid-state laser rod 2 is excited with high power and high efficiency. Beam quality laser light can be obtained.

Embodiment 2. FIG.
12A and 12B are diagrams showing the configuration of a solid-state laser rod excitation module according to Embodiment 2 of the present invention. FIG. 12A is a cross-sectional view cut in a direction perpendicular to the axial direction of the solid-state laser rod 2, and FIG. Sectional drawing along CC line in A), (C) is an enlarged view of C part in (A). In (A) to (C), 31 is a solid-state laser rod excitation module, and 34 is a specular reflection reflecting cylinder, which is arranged substantially coaxially with the solid-state laser rod 2 and surrounding the solid-state laser rod 2 and the cooling sleeve 3. It has a cylindrical shape that is mirror-reflective with respect to the semiconductor laser light. Reference numeral 37 denotes a semiconductor laser light introduction means provided in the specular reflection reflecting cylinder 34, and introduces the semiconductor laser light condensed by the semiconductor laser light condensing means 6 into the specular reflection reflecting cylinder 34. The other components are the same as or equivalent to those shown in FIG. 1 with the same reference numerals, and detailed description thereof will be omitted. In FIG. 12A, an arrow X indicates a direction (slow axis direction) perpendicular to the axial direction of the solid-state laser rod 2, and in FIG. 12B, an arrow Y indicates a direction parallel to the axial direction of the solid-state laser rod 2 (fast Axial direction). FIG. 12B shows a state in which the coolant flows.

  In the second embodiment, the specular reflection reflecting cylinder 34 is constituted by a highly reflective coating film formed on the outer peripheral surface of the cooling sleeve 3, and the semiconductor laser light introducing means 37 is reduced on the outer peripheral surface of the cooling sleeve 3 in a slit shape. It is composed of a reflective coating film. In this case, the size of the semiconductor laser light introducing means 37 constituted by the antireflection coating film formed in the slit shape is set to be approximately the same as the size of the semiconductor laser light focused on the line by the aspherical lens 6b. The confinement efficiency of the semiconductor laser light in the cylinder 34 is increased. Further, the semiconductor laser light diffusing means 8 is configured by roughening the inner peripheral surface of the cooling sleeve 3 in the form of ground glass.

  When the solid-state laser rod excitation module 31 is configured in this way, the laser beams emitted from the bar-shaped elements 5-1 to 5-5 in the semiconductor laser beam output device 5a are opposed to the cylindrical lenses 6-1 to 6-6 facing each other. Parallelized by -5. The paralleled semiconductor laser beam is parallel to the stacking direction of the five bar-shaped elements 5-1 to 5-5 by the aspherical lens 6b (the direction parallel to the axial direction of the solid laser rod 2 and the fast axis direction). It is condensed on the line. The semiconductor laser beam condensed on the line is introduced into the specular reflecting reflector 34 from the semiconductor laser light introducing means 37 constituted by the anti-reflection coating film located at the condensing position. The semiconductor laser light introduced into the specular reflective cylinder 34 is diffused on the inner peripheral surface of the cooling sleeve 3. In FIG. 12C, the state in which the semiconductor laser light is diffused by the semiconductor laser light diffusion means 8 formed on the inner peripheral surface of the cooling sleeve 3 is indicated by arrows. The diffused semiconductor laser light is uniformly distributed in the diffusive reflector 4 and is incident on the solid laser rod 2 and absorbed.

  As described above, according to the second embodiment, the solid-state laser rod excitation module 31 includes the solid-state laser rod 2, the cooling sleeve 3, the specular reflective reflector 34, the stacked semiconductor laser 5, and the semiconductor. Since the semiconductor laser light output device 5a comprising the laser light condensing means 6, the semiconductor laser light introducing means 37, and the semiconductor laser light diffusing means 8, the solid laser rod 2 is excited with high power and high efficiency. Beam quality laser light can be obtained.

  If the semiconductor laser light diffusing means 8 is not provided, the focal point of the aspherical lens 6b is adjusted so that the condensing angle at the aspherical lens 6b falls within the angle at which the solid laser rod 2 is viewed from the semiconductor laser light introducing means 37. It is necessary to adjust the distance, and as a result, the size of the semiconductor laser light introducing means 37 is increased, and the confinement efficiency of the semiconductor laser light in the specular reflective reflector 34 is lowered.

Embodiment 3 FIG.
In the first embodiment and the second embodiment, one semiconductor laser light irradiating means composed of the stack type semiconductor laser 5, the semiconductor laser light focusing means 6, the semiconductor laser light introducing means 37, and the semiconductor laser light diffusing means 8 is provided. Although the system to be used has been described, in the system described in the first or second embodiment as shown in FIG. 13, a plurality of semiconductor laser light irradiation means 22 are arranged around the solid laser rod 2 to excite the solid laser rod. The configuration of the module 21 is the third embodiment. According to the third embodiment, the intensity of the semiconductor laser light is increased within the solid-state laser rod 2 and the intensity distribution is more axially symmetric and uniform, so that a laser beam with higher power and higher beam quality can be obtained. Can do.

Embodiment 4 FIG.
14A and 14B are diagrams showing a configuration of a semiconductor laser light output device according to Embodiment 4 of the present invention, in which FIG. 14A is a cross-sectional view along the slow axis direction, and FIG. 14B is a line AA in FIG. FIG. 1A and 1B, reference numeral 5 ′ denotes an array semiconductor laser of a bar-like element configured by integrating a plurality of laser light emission ends in the slow axis direction. The laser light emitted from the array semiconductor laser 5 ′ has a spread angle of about 10 ° in the slow axis direction, but has a large spread angle of about 30 ° in the fast axis direction.

  A semiconductor laser beam condensing means 6 condenses the laser beam emitted from the array semiconductor laser 5 '. Reference numeral 6-1 denotes a cylindrical lens which is opposed to the bar-shaped element of the array semiconductor laser 5 'and is disposed at a position substantially away from the opposed bar-shaped element by its focal length, and is emitted from the opposed bar-shaped element. The parallel laser beam is collimated. Reference numeral 6b denotes an aspheric lens that condenses the semiconductor laser beam collimated by the cylindrical lens 6-1 in the fast axis direction of the array semiconductor laser 5 '. Reference numeral 15 denotes a roof type prism as a semiconductor laser beam refracting means for refracting the laser beam emitted from the array semiconductor laser 5 ′. The ridge line of the roof type prism 15 is set in a direction parallel to the fast axis direction. The surface facing the ridge line is installed substantially perpendicular to the traveling direction of the semiconductor laser light, and refracts the semiconductor laser light emitted from the cylindrical lens 6-1 in the slow axis direction.

  Since the semiconductor laser beam condensing means 6 is the same as that described in the first embodiment, a duplicate description is omitted. Hereinafter, the roof prism 15 will be described in detail, and then the operation of the semiconductor laser light output device of the fourth embodiment will be described.

  The roof prism 15 refracts the laser light emitted from the array semiconductor laser 5 '. Further, in order to concentrate the energy of all the semiconductor laser light in a limited range with an arbitrary size, it is necessary to keep the size of the semiconductor laser light in the slow axis direction small.

  The roof prism 15 is between the cylindrical lens 6-1 and the aspheric lens 6b, and the cut surface including the ridge line of the roof prism 15 is inclined in the slow axis direction with respect to the traveling direction of the semiconductor laser light. A refractive power is given to the semiconductor laser light in the slow axis direction. As a result, the semiconductor laser light incident on the roof prism 15 is refracted in the slow axis direction and emitted in a direction inclined at an arbitrary angle toward the center (refracted at an arbitrary angle on the AA line side in FIG. 14). To do). Accordingly, it is possible to refract the traveling direction of the semiconductor laser light spread at a position separated by an arbitrary distance in advance, and to suppress the size of the semiconductor laser light in the slow axis direction.

Next, the operation will be described.
Laser light emitted from the array semiconductor laser 5 ′ is collimated in the fast axis direction by the opposing cylindrical lens 6-1. The semiconductor laser light emitted from the cylindrical lens 6-1 is refracted in the slow axis direction by the roof prism 15 and emitted. The laser beam emitted from the roof prism 15 is incident on the aspheric lens 6b with the size in the slow axis direction being suppressed to be smaller than the size in the slow axis direction of the aspheric lens 6b, and is arrayed by the aspheric lens 6b. It is focused on a line in the fast axis direction of the semiconductor laser 5 '. As a result, it is possible to increase the energy utilization efficiency by outputting all the semiconductor laser light in a limited range at a position away from the arbitrary position by the focal length of the aspheric lens 6b. Thereby, the semiconductor laser light output device 5b as a whole can be downsized.

  FIG. 14 shows the case where the roof prism 15 is installed between the cylindrical lens 6-1 and the aspherical lens 6b, but the semiconductor is controlled by suppressing the spread of the laser light in the slow axis direction. As long as the laser beam can be incident on the laser beam introduction unit, the laser beam may be installed at a position on the optical axis of the other semiconductor laser beam without being limited to the above arrangement.

  As described above, according to the fourth embodiment, the semiconductor laser light output device 5b includes the above-described array type semiconductor laser 5 ′, the semiconductor laser light condensing means 6, the roof type prism (semiconductor laser light refracting means). 15), a laser beam obtained by synthesizing power with high density using a semiconductor laser beam can be obtained in a small size and with high efficiency.

Embodiment 5 FIG.
15A and 15B are sectional views showing the configuration of a semiconductor laser light output device according to a fifth embodiment of the present invention. FIG. 15A is a sectional view along the slow axis direction, and FIG. 15B is AA in FIG. It is sectional drawing along a line. In FIGS. 15A and 15B, reference numerals 5-1 to 5-5 denote bar-shaped elements constituting the stack type semiconductor laser 5. The stack type semiconductor laser 5 is configured by laminating a plurality of bar-shaped elements 5-1 to 5-5 configured by integrating a plurality of laser light emitting ends in the slow axis direction in the fast axis direction. The laser beams emitted from the bar-shaped elements 5-1 to 5-5 have a spread angle of about 10 ° in the slow axis direction, but have a large spread angle of about 30 ° in the fast axis direction.

  Reference numeral 6 denotes a semiconductor laser beam condensing means for condensing the laser beam emitted from the stack type semiconductor laser 5. Reference numerals 6-1 to 6-5 denote cylindrical lenses which are opposed to the different bar-shaped elements 5-1 to 5-5 constituting the stacked semiconductor laser 5, and from the opposed bar-shaped elements 5-1 to 5-5. The laser beams emitted from the opposing bar-shaped elements 5-1 to 5-5 are made parallel to each other at a position separated by the approximate focal length. Reference numeral 6a denotes a cylindrical lens array, which includes cylindrical lenses 6-1 to 6-5. An aspherical lens 6b condenses the semiconductor laser light collimated by the cylindrical lenses 6-1 to 6-5 in a direction (fast axis direction) parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5. It is.

  Reference numeral 15a denotes a prism prism which is a semiconductor laser beam refracting means for refracting the laser beam emitted from the stack type semiconductor laser 5. The ridge line portion of the roof type prism is cut off by a plane parallel to the surface facing the ridge line of the roof type prism. This is a prismatic prism with a trapezoidal cross section. The arrangement in the semiconductor laser light output device 5c is such that the ridge line imaginary by the roof prism of the prismatic prism 15a is parallel to the fast axis direction, and the surface facing the imaginary ridge line by the roof prism is a stack type semiconductor. It is installed substantially perpendicular to the traveling direction of the semiconductor laser light output from the laser 5, and the semiconductor laser light emitted from each of the cylindrical lenses 6-1 to 6-5 is partially refracted in the slow axis direction. .

  FIG. 15 shows a case where five bar-shaped elements 5-1 to 5-5 and five cylindrical lenses 6-1 to 6-5 are provided, but a plurality other than five is provided. In some cases.

  Since the semiconductor laser beam condensing device 6 is the same as that of the first embodiment, a duplicate description is omitted. Hereinafter, after describing the prism prism 15a in detail, the operation of the semiconductor laser light output device will be described.

  The semiconductor laser light incident on the cut surface including the virtual ridge line by the roof prism of the prism prism 15a is refracted and tilted at an arbitrary angle toward the center (A-A line in FIG. 15A). Exit. Therefore, it is possible to refract the traveling direction of the semiconductor laser light spread at a position separated by an arbitrary distance in advance, and to suppress the size of the semiconductor laser light in the slow axis direction.

Next, the operation will be described.
Laser beams emitted from the bar-shaped elements 5-1 to 5-5 are collimated in the fast axis direction by the opposed cylindrical lenses 6-1 to 6-5. The semiconductor laser light emitted from the cylindrical lenses 6-1 to 6-5 is partially refracted in the slow axis direction by the prismatic prism 15a, and the size in the slow axis direction becomes the size in the slow axis direction of the aspherical lens 6b. It is suppressed and enters the aspherical lens 6b. Thereafter, the light is condensed on a line in a direction (fast axis direction) parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 by the aspheric lens 6b. As a result, it is possible to increase the energy utilization efficiency by outputting all the semiconductor laser light in a limited range at a position away from the arbitrary position by the focal length of the aspheric lens 6b. As a result, the semiconductor laser light output device 5c itself can be miniaturized.

  FIG. 15 shows the case where the prismatic prism 15a is installed between the cylindrical lens array 6a and the aspherical lens 6b. However, the semiconductor laser beam is suppressed by suppressing the spread of the laser beam in the slow axis direction. Any other position on the optical axis of the semiconductor laser light may be used as long as the laser light can be incident on the introducing means without being limited to the above arrangement.

  In the fifth embodiment, the semiconductor laser light refracting means is the prism prism 15a, but the same effect may be obtained in the roof prism 15 in some cases. In the fourth embodiment, the semiconductor laser beam refracting means is the roof type prism 15, but the same effect may be obtained in the prism prism 15a.

  As described above, according to the fifth embodiment, the semiconductor laser light output device 5c is composed of the stack type semiconductor laser 5, the semiconductor laser light focusing means 6, and the prism prism (semiconductor laser light refracting means) 15a. Therefore, it is possible to obtain a laser beam that is synthesized with high density using a semiconductor laser beam in a small size and with high efficiency.

Embodiment 6 FIG.
In the sixth embodiment, the semiconductor laser light output device 5c described in the fifth embodiment is used for the solid-state laser rod excitation module of the first embodiment.

  FIG. 16 is a cross-sectional view showing a configuration of a solid-state laser rod excitation module according to Embodiment 6 of the present invention, where (A) is a cross-sectional view along the slow axis direction, and (B) is AA in (A). It is sectional drawing along a line. In the figure, 300 is a solid-state laser rod excitation module, 5c is a semiconductor laser light output device used in the solid-state laser rod excitation module 300, and 2 is a solid-state laser rod whose axial direction is parallel to the fast axis direction of the stacked semiconductor laser 5. . In addition, what attached | subjected the code | symbol same as FIG. 1 is the same component, and it abbreviate | omits the overlapping description.

Next, operations different from those in the first embodiment will be mainly described.
The laser light emitted from the stack type semiconductor laser 5 is condensed in the fast axis direction by the cylindrical lens array 6a, and then partially refracted in the slow axis direction by the prism prism 15a which is a semiconductor laser light refracting means. Accordingly, the size of the semiconductor laser light in the slow axis direction is suppressed within the size of the aspheric lens 6b in the slow axis direction and enters the aspheric lens 6b. The semiconductor laser light focused on the line in the direction parallel to the stacking direction of the bar-shaped elements 5-1 to 5-5 (fast axis direction) by the aspherical lens 6b is passed through the semiconductor laser light introducing means 7 and is a solid laser rod. 2 is irradiated. In the first embodiment, the laser beam emitted from the cylindrical lens array 6a has a size in the slow axis direction that falls within the size in the slow axis direction of the aspherical lens 6b (a position from the cylindrical lens array 6a). Since the aspherical lens 6b could not be arranged, the semiconductor laser light introducing means 7 may be sized so as to protrude from the diffusive reflector 4 as shown in FIG. Although the laser light confinement efficiency of the means 7 could not be increased, in the sixth embodiment, the semiconductor laser light introducing means 7 is installed without jumping out from the diffusive reflector 4 as shown in FIG. Since all the laser beams emitted from the cylindrical lens array 6a by the prism prism 15a can enter the aspherical lens 6b. It is possible to improve the semiconductor laser beam laser light confining efficiency of the introduction means 7. Since the subsequent operation is the same as that of the first embodiment, the description thereof is omitted.

  As described above, according to the sixth embodiment, the spread of the semiconductor laser light in the fast axis direction is suppressed by the semiconductor laser beam condensing means 6, and the spread in the slow axis direction is suppressed by the prism prism 15a. It is possible to obtain highly efficient semiconductor laser light with high power synthesis at a position separated by a distance. In particular, since the prismatic prism 15a suppresses the spread of laser light in the slow axis direction, unlike the case of the first embodiment, the size of the semiconductor laser light introducing means 7 in the slow axis direction can be reduced. Since the confinement efficiency of the laser light of the light introducing means 7 is improved, the solid laser rod 2 can be excited with high power and high efficiency, and laser light with high beam quality can be obtained. Furthermore, since the semiconductor laser light output device 5c can be downsized, the entire solid laser rod excitation module 300 can be downsized.

Embodiment 7 FIG.
In the sixth embodiment, the solid laser rod excitation module including the solid laser rod, the cooling sleeve, the diffusive reflector, the semiconductor laser light output device, and the semiconductor laser light introducing means whose axial direction is parallel to the fast axis direction. As described above, a solid laser rod excitation module comprising a solid laser rod, a cooling sleeve, a diffusive reflector, a semiconductor laser beam output device, and a semiconductor laser beam introduction means whose axial direction is parallel to the slow axis direction is implemented. It is form 7.

  FIG. 17 is a cross-sectional view showing a configuration of a solid-state laser rod excitation module according to Embodiment 7 of the present invention, where (A) is a cross-sectional view along the slow axis direction, and (B) is AA in (A). It is sectional drawing along a line. In the figure, 310 is a solid-state laser rod excitation module, 5c is a semiconductor laser light output device used for the solid-state laser rod excitation module 310, and 2 is a solid-state laser rod whose axial direction is parallel to the slow axis direction of the stacked semiconductor laser. The other components are the same as or equivalent to those shown in FIG. 1 with the same reference numerals, and detailed description thereof will be omitted.

  According to the seventh embodiment, if the area of the second end face 12b is smaller than the area of the first end face 12a of the slab waveguide 12 described in the first embodiment, the semiconductor laser light from the semiconductor laser light introducing means 7 is used. Since the solid laser rod 2 can be excited with high efficiency, the laser beam combined with high density at a position separated by an arbitrary distance can be obtained in a small size and with high efficiency. .

Embodiment 8 FIG.
In the eighth embodiment, the semiconductor laser light output device 5c described in the fifth embodiment is used for the solid-state laser rod excitation module of the second embodiment.

  18A and 18B are diagrams showing a configuration of a solid-state laser rod excitation module according to an eighth embodiment of the present invention, in which FIG. 18A is a cross-sectional view along the slow axis direction, and FIG. 18B is a CC line in FIG. FIG. In the figure, 320 is a solid-state laser rod excitation module, and 34 is a specular reflection reflecting cylinder, which is arranged substantially coaxially with the solid-state laser rod 320 and surrounds the solid-state laser rod 2, and is specularly reflective to semiconductor laser light. It has a cylindrical shape. Reference numeral 37 denotes a semiconductor laser light introduction means provided in the specular reflection reflecting cylinder 34, and introduces the semiconductor laser light condensed by the semiconductor laser light condensing means 6 into the specular reflection reflecting cylinder 34. The other components are the same as or equivalent to those shown in FIG. 12 with the same reference numerals, and detailed description thereof is omitted.

Next, the operation will be described.
The laser beams emitted from the bar-shaped elements 5-1 to 5-5 are collimated in the fast axis direction by the opposing cylindrical lens array 6a. The semiconductor laser beam emitted from the cylindrical lens array 6a is partially refracted in the slow axis direction by the prism prism 15a and emitted. The semiconductor laser light emitted from the prismatic prism 15a is incident on the aspheric lens 6b with the size in the slow axis direction being suppressed to the size in the slow axis direction of the aspheric lens 6b. The light is condensed on a line in a direction (fast axis direction) parallel to the stacking direction of -1 to 5-5. The semiconductor laser light focused on the line is controlled by the slow-axis direction of the semiconductor laser light introducing means 37, and the semiconductor laser light focused on the line is composed of a dereflection coating film positioned at the converging position. The laser light is introduced from the laser light introducing means 37 into the specular reflecting reflector 34.

  According to the eighth embodiment, the semiconductor laser beam is prevented from spreading in the fast axis direction by the semiconductor laser beam condensing means 6, and the spread in the slow axis direction is suppressed by the prism prism 15a, and a position separated by an arbitrary distance. It is possible to obtain a semiconductor laser beam synthesized with high density at a high efficiency. Thereby, the solid laser rod 2 can be excited with high power and high efficiency, and laser beam with high beam quality can be obtained. Further, since the semiconductor laser light output device 5c can be downsized, the entire solid laser rod excitation module 320 can be downsized.

  In the eighth embodiment, the axial direction of the solid laser rod 2 is parallel to the fast axis direction of the stacked semiconductor laser 5, and the cooling sleeve 3 surrounds the solid laser rod 2 substantially coaxially with the solid laser rod 2. The mirror-reflective reflector 34 is arranged substantially coaxially with the solid-state laser rod 2 and surrounding the solid-state laser rod 2 and the cooling sleeve 3, but the axial direction of the solid-state laser rod 2 is aligned with the stacked semiconductor laser 5. The cooling sleeve 3 is arranged so as to surround the solid laser rod 2 substantially coaxially with the solid laser rod 2, and the specular reflection reflecting cylinder 34 is arranged substantially coaxially with the solid laser rod 2. Even if the rod 2 and the cooling sleeve 3 are disposed so as to surround the same, the same effect can be obtained. Further, in the second embodiment, the semiconductor laser light diffusing means 8 is provided in the specular reflection reflecting tube 34. However, in this eighth embodiment, the prismatic prism 15a suppresses the spread of the laser light in the slow axis direction. It is not necessary to adjust the focal length of the aspherical lens 6b so that the converging angle of the aspherical lens 6b is within the angle at which the solid laser rod 2 is viewed from the semiconductor laser light introducing means 37, and the semiconductor laser light diffusing means 8 is not provided. However, the size of the semiconductor laser light introducing means 37 is not increased (as shown in FIGS. 12A and 18A), the size of the semiconductor laser light introducing means 37 is remarkably different in the eighth embodiment. Can be made small). Thereby, the confinement efficiency of the semiconductor laser light in the specular reflecting reflector 34 is not lowered.

  In the sixth to eighth embodiments, the semiconductor laser light refracting means is the prism prism 15a. However, the same effect can be obtained with a roof prism.

It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 1 of this invention. It is sectional drawing with which it uses for description of the semiconductor laser beam condensing means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is a graph with which it uses for description of the aspherical lens which comprises the semiconductor laser beam condensing means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is sectional drawing which shows the structure of the aspherical surface synthetic lens which comprises the semiconductor laser beam condensing means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is sectional drawing with which it uses for description of a problem at the time of comprising a semiconductor laser beam introduction means only with a slit. It is sectional drawing which shows the structure of another semiconductor laser beam introduction means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is sectional drawing which shows the structure of the semiconductor laser beam introduction means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is explanatory drawing explaining reflection in the slab waveguide of the light beam of a semiconductor laser beam. Longitudinal axis of slab waveguide when slab waveguide is formed by BK7 (n ₂ = 1.516) or YAG (n ₂ = 1.82) with the spread angle in the slow axis direction of the semiconductor laser light being 10 ° It is a graph which shows the relationship between the inclination angle (alpha) from a direction, and the frequency | count of reflection restrict | limited within a slab waveguide. It is sectional drawing with which it uses for description of the problem at the time of not providing a semiconductor laser beam diffusion means. It is sectional drawing with which it uses for description of operation | movement of the semiconductor laser light diffusion means used for the solid-state laser rod excitation module by Embodiment 1 of this invention. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 2 of this invention. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 3 of this invention. It is a figure which shows the structure of the semiconductor laser beam output apparatus by Embodiment 4 of this invention, (A) is sectional drawing along a slow-axis direction, (B) followed the AA line in (A). It is sectional drawing. It is a figure which shows the structure of the semiconductor laser beam output device by Embodiment 5 of this invention, (A) is sectional drawing along a slow-axis direction, (B) followed the AA line in (A). It is sectional drawing. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 6 of this invention, (A) is sectional drawing along a slow-axis direction, (B) is along the AA line in (A). FIG. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 7 of this invention, (A) is sectional drawing along a slow-axis direction, (B) is along the AA line in (A). FIG. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by Embodiment 8 of this invention, (A) is sectional drawing along a slow-axis direction, (B) is along the CC line in (A). FIG. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by the prior art example 1. It is sectional drawing which shows the structure of the semiconductor laser beam output device used for the solid-state laser rod excitation module by the prior art example 2. FIG. It is sectional drawing which shows the structure of the solid-state laser rod excitation module by the prior art example 2. FIG. It is sectional drawing with which it uses for description of the problem of the solid-state laser rod excitation module by the prior art example 2. FIG.

Explanation of symbols

  1, 21, 31, 300, 310, 320 Solid laser rod excitation module, 2 solid laser rod, 3 cooling sleeve, 4 diffusive reflector, 5 stack type semiconductor laser, 5 ′ array semiconductor laser, 5a, 5b, 5c semiconductor Laser light output device, 5-1 to 5-5 bar-shaped element, 6 semiconductor laser light focusing means, 6a cylindrical lens array, 6b aspherical lens, 6c aspherical synthetic lens, 6-1 to 6-5 cylindrical lens, 7, 37 Semiconductor laser light introducing means, 8 Semiconductor laser light diffusing means, 11 Slit, 12 Slab waveguide, 12a First end face, 12b Second end face, 12c Third end face, 12d Fourth end face, 12e First 5 end face, 12f sixth end face, 13 adhesive layer, 15 roof type prism (semiconductor laser beam refracting means) , 15a prismatic prism (laser beam refraction means), 22 a semiconductor laser beam irradiation unit, 34 specular reflection tube.

Claims (14)

A cylindrical cooling sleeve disposed around the solid laser rod substantially coaxially with the solid laser rod;
A cylindrical diffusive reflector disposed around the solid laser rod and the cooling sleeve substantially coaxially with the solid laser rod;
A semi-conductor laser beam output device and the fast axis direction in the axial direction of the semiconductor laser output was the solid-state laser rod laser light is arranged in parallel toward the diffusive reflector tube,
A semiconductor laser beam provided in the diffusive reflector and introducing the laser beam emitted from the semiconductor laser output device toward the solid laser rod of the diffusive reflector while maintaining the size in the fast axis direction. And introducing means ,
The semiconductor laser light output device is
An array semiconductor laser that is a bar-shaped element configured by integrating a plurality of laser light emission ends in the slow axis direction;
First semiconductor laser beam refracting means for refracting laser light emitted from the array semiconductor laser in a fast axis direction of the array semiconductor laser;
A second semiconductor laser light refracting means which is provided before or after the first semiconductor laser light refracting means and refracts laser light emitted from the array semiconductor laser in the slow axis direction of the array semiconductor laser;
Laser light emitted from the array semiconductor laser is provided before or after the first semiconductor laser light refracting means and before or after the second semiconductor laser light refracting means. A solid-state laser rod excitation module comprising: a semiconductor laser beam condensing unit that condenses light in the fast axis direction and in the slow axis direction. A cylindrical cooling sleeve disposed around the solid laser rod substantially coaxially with the solid laser rod;
A cylindrical diffusive reflector disposed around the solid laser rod and the cooling sleeve substantially coaxially with the solid laser rod;
A semi-conductor laser beam output device and the fast axis direction in the axial direction of the semiconductor laser output was the solid-state laser rod laser light is arranged in parallel toward the diffusive reflector tube,
A semiconductor laser beam provided in the diffusive reflector and introducing the laser beam emitted from the semiconductor laser output device toward the solid laser rod of the diffusive reflector while maintaining the size in the fast axis direction. And introducing means ,
The semiconductor laser light output device is
A stack type semiconductor laser constituted by laminating a plurality of bar-like elements constructed by integrating a plurality of laser light emitting ends in the slow axis direction in the fast axis direction;
First semiconductor laser beam refracting means for refracting laser light emitted from the stacked semiconductor laser in the fast axis direction of the stacked semiconductor laser;
A second semiconductor laser light refracting means provided before or after the first semiconductor laser light refracting means and refracting the laser light emitted from the stack type semiconductor laser in the slow axis direction of the stack type semiconductor laser; ,
Laser light emitted from the stack type semiconductor laser is provided before or after the first semiconductor laser light refracting means and before or after the second semiconductor laser light refracting means. the solid-state laser rod pumping module, characterized in that a semiconductor laser beam focusing means for focusing the slow axis direction together with condensed in the fast axis direction. A cylindrical cooling sleeve disposed around the solid laser rod substantially coaxially with the solid laser rod;
A cylindrical specular reflective cylinder disposed around the solid laser rod and the cooling sleeve substantially coaxially with the solid laser rod;
The Towards specular reflection tube outputs a laser beam, a semi-conductor laser beam output device and the fast axis direction in the axial direction of the semiconductor laser of the solid laser rod is arranged in parallel,
A semiconductor provided in the specular reflection cylinder and introducing laser light emitted from the semiconductor laser output device toward the solid laser rod of the specular reflection cylinder while maintaining the size in the fast axis direction. Laser light introducing means ,
The semiconductor laser light output device is
An array semiconductor laser that is a bar-shaped element configured by integrating a plurality of laser light emission ends in the slow axis direction;
First semiconductor laser beam refracting means for refracting laser light emitted from the array semiconductor laser in a fast axis direction of the array semiconductor laser;
A second semiconductor laser light refracting means which is provided before or after the first semiconductor laser light refracting means and refracts laser light emitted from the array semiconductor laser in the slow axis direction of the array semiconductor laser;
Laser light emitted from the array semiconductor laser is provided before or after the first semiconductor laser light refracting means and before or after the second semiconductor laser light refracting means. A solid-state laser rod excitation module comprising: a semiconductor laser beam condensing unit that condenses light in the fast axis direction and in the slow axis direction. A cylindrical cooling sleeve disposed around the solid laser rod substantially coaxially with the solid laser rod;
A cylindrical specular reflective cylinder disposed around the solid laser rod and the cooling sleeve substantially coaxially with the solid laser rod;
The Towards specular reflection tube outputs a laser beam, a semi-conductor laser beam output device and the fast axis direction in the axial direction of the semiconductor laser of the solid laser rod is arranged in parallel,
A semiconductor provided in the specular reflection cylinder and introducing laser light emitted from the semiconductor laser output device toward the solid laser rod of the specular reflection cylinder while maintaining the size in the fast axis direction. Laser light introducing means ,
The semiconductor laser light output device is
A stack type semiconductor laser constituted by laminating a plurality of bar-like elements constructed by integrating a plurality of laser light emitting ends in the slow axis direction in the fast axis direction;
First semiconductor laser beam refracting means for refracting laser light emitted from the stacked semiconductor laser in the fast axis direction of the stacked semiconductor laser;
A second semiconductor laser light refracting means provided before or after the first semiconductor laser light refracting means and refracting the laser light emitted from the stack type semiconductor laser in the slow axis direction of the stack type semiconductor laser; ,
Laser light emitted from the stack type semiconductor laser is provided before or after the first semiconductor laser light refracting means and before or after the second semiconductor laser light refracting means. the solid-state laser rod pumping module, characterized in that a semiconductor laser beam focusing means for focusing the slow axis direction together with condensed in the fast axis direction. The second semiconductor laser beam refracting means is:
The roof prism has a ridge line parallel to the fast axis direction of the semiconductor laser, and a surface facing the ridge line of the roof prism is set substantially perpendicular to the traveling direction of the semiconductor laser light. The semiconductor laser light output device according to claim 1 , wherein the semiconductor laser light output device is a semiconductor laser light output device. The second semiconductor laser beam refracting means is:
The ridgeline portion of the roof prism is cut out by a plane parallel to the surface facing the ridgeline of the roof prism, and the cross section is a trapezoidal prism prism. a direction parallel to, claim from claim 1, characterized in that surface facing the ridge and virtual above roof prism of the prism prism is placed substantially perpendicularly to the traveling direction of the semiconductor laser beam 4. The semiconductor laser light output device according to claim 1. The semiconductor laser light introducing means is
A slit formed in the diffusive reflector,
A hexahedral slab waveguide disposed in the slit;
Of the six end faces of the slab waveguide, provided in the gap between the slit and the four end faces other than the first end face on which the laser light is incident and the second end face from which the laser light is emitted, the refractive index is higher than that of the slab waveguide. The solid laser rod excitation module according to claim 1 , further comprising a small adhesive layer. The semiconductor laser light introducing means is
The area of the second end face is smaller than the area of the first end face, and the length of the second end face in the direction perpendicular to the axial direction of the solid laser rod is larger than the diameter of the solid laser rod. The solid laser rod excitation module according to claim 7. The semiconductor laser light introducing means is
8. The solid-state laser rod excitation module according to claim 7, wherein the number of times the incident semiconductor laser light is reflected at the end face in the direction perpendicular to the fast axis direction of the semiconductor laser is at most one. Between the semiconductor laser beam introducing means and the solid-state laser rod, of the claims 1 to 9, characterized in that with a semiconductor laser light diffusing means for diffusing the laser beam introduced by the semiconductor laser beam introduction means The solid-state laser rod excitation module according to any one of the above. 11. The solid-state laser rod excitation module according to claim 10, wherein the semiconductor laser light diffusing means is made of a transparent optical material whose surface is roughened in a ground glass shape. 11. The solid laser rod excitation module according to claim 10, wherein the semiconductor laser light diffusing means is made of a transparent foamable glass material containing bubbles. 13. The solid laser rod excitation module according to claim 11 , wherein the semiconductor laser light diffusion means is formed on a cooling sleeve. 12. The solid laser rod excitation module according to claim 11 , wherein the semiconductor laser light diffusing means comprises sapphire.

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