JPH05102567A - Solid-state laser oscillation system - Google Patents

Abstract

PURPOSE:To provide a long lifetime solid-state laser oscillation system capable of oscillating a laser beam which is high in oscillation efficiency and excellent in the quality of output beam. CONSTITUTION:The medium of a solid-state laser medium rod 10 is resonated and oscillated by the laser light from a semiconductor laser 8. The oscillation laser light is resonated and amplified in a resonator while its wavelength is selected by an etalon 12 in the resonator. The laser light is harmonized in an acousto-optical OMEGA switch 13 and synchronized to an outside signal by an acousto-optic synchronizing switch 14 so that it may be output as a single mode laser from an output plane mirror.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state laser oscillation system, and more particularly to a solid laser oscillation system of the Kaizenga type in which a semiconductor laser excites a solid-state laser medium to generate a laser beam.

[0002]

2. Description of the Related Art Conventionally, as a solid-state laser oscillation system, a Kaizenga type forced mode-locked oscillator has been used in IEEE OF QUANTUM ELECTRONICS, VOL. QE-17,
It is known from P.1694 (1981). In this Kaizenger type forced mode-locked oscillator, a flash lamp is used as an excitation light source, and the excitation light from this flash lamp excites the solid-state laser medium to generate a laser beam.

FIG. 2 shows this forced mode locked oscillator. In FIG. 2, 2 is a solid laser medium,
For example, a YAG rod is shown, and this solid-state laser medium 2
Is excited by excitation light from a flash lamp as an excitation light source arranged around this, and laser light is multimode-oscillated. This laser light is oscillated between a resonator mirror 6 that constitutes a resonator and a mirror 7 through which a laser beam is extracted, and the oscillated laser light is placed in the optical path of this resonator. ,
The light is mode-locked in the resonator by propagating through the etalon plate 4 and the acousto-optical forced mode-locking element 5, and the mirror 7 is formed as a single-mode pulse laser beam having a specific wavelength.
Taken from. That is, the multimode continuous wave laser light from the solid-state laser medium 2 is wavelength-selected by the etalon plate 4, the laser light of a specific wavelength is tuned, the mode is synchronized with the acousto-optic Q switch 3, and the acousto-optic laser is used. The statically forced mode synchronization element 5 synchronizes with a synchronization signal from the outside. Therefore, a laser beam having a sharp peak level is generated from the forced mode-locked oscillator shown in FIG.

[0004]

In the oscillator as shown in FIG. 2, since the flash lamp is used as the excitation light source, there are the following problems. That is, since a flash lamp generates excitation light having a wide emission spectrum, the excitation efficiency as a laser oscillator is poor, and high heat is generated.
There is a problem that the refractive index in the YAG rod is changed and the oscillation becomes unstable. Further, it is necessary to provide a cooling device for cooling the solid-state laser medium for such a thermal countermeasure, and there is a problem that the oscillator itself becomes large. Further, even if a cooling device is provided, there is a problem that a poor quality laser beam is oscillated as an output laser beam. Furthermore, a laser oscillator using a flash lamp as an excitation light source has a problem that its life is short, about 400 hours.

The object of the present invention was made in view of the above-mentioned circumstances, and provides a long-lived solid-state laser oscillation system capable of oscillating a laser beam with high oscillation efficiency and good output laser beam quality. There is

[0006]

According to the present invention, a solid-state laser medium, a semiconductor laser for continuously supplying a pumping laser beam to the solid-state laser medium, and a laser beam generated from the solid-state laser medium are resonantly amplified. An optical resonator, a wavelength selection element arranged in the resonator for selecting a specific wavelength, and a tuning synchronization optical means arranged in the resonator for tuning and synchronizing the oscillated laser light. A solid-state laser oscillation system is provided.

[0007]

In the solid-state laser oscillation system of the present invention, since the semiconductor laser continuously supplies the excitation laser beam having the optimum wavelength for resonantly exciting the solid-state laser medium to the solid-state laser medium, The medium can be excited with high efficiency, and since the solid-state laser medium is not unnecessarily heated, the quality of the laser beam generated from this can be improved. Moreover, since the semiconductor laser is used as the excitation light source, the life of the solid-state laser oscillation system can be extended.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A solid-state laser oscillation system according to embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a solid-state laser oscillation system of the Kaizenga type. 1 in FIG.
Is a solid-state laser medium such as YAG, YLF, YV
O4 or a glass rod is shown, and one surface 10A of the rod of the solid laser medium is directed to the semiconductor laser 8, that is, the laser diode through the condenser lens system 9. The one surface 10A of the rod allows the laser light for excitation generated from the semiconductor laser 8 to pass therethrough,
A reflective film that selectively reflects the oscillated laser light is coated. In addition, the other surface 10B of the rod 10 effectively causes the oscillated laser light to travel to one surface 10B of the rod 10.
It is cut at Brewster's angle with respect to the optical axis in order to lead to the reflection film of A.

On the optical axes of the semiconductor laser 8, the focusing optical system 9 and the laser medium rod 10, the astigmatism given to the oscillated laser beam on the other surface 10B of the rod 10 as a Brewster surface is corrected. A concave mirror 11 is arranged in the. In this concave mirror 11, the angle θ formed by the optical axes 18 and 19 of the P wave regulated by the Brewster cut surface 10B and the reflected wave reflected by the concave mirror 11 is appropriately determined in order to correct astigmatism. The plane of polarization of the P wave and the plane of polarization of the reflected wave are formed on the same plane. A plane mirror 15 for outputting an oscillated laser beam is arranged on the optical axis 19 so as to face the concave mirror 11. One surface 10A of the plane mirror 15 and the rod 10
A laser resonator is constituted by the reflective film of. Between the concave mirror 11 and the plane mirror 15, an etalon plate 12 for selecting an oscillation wavelength, an acousto-optical Q switch 13 for tuning the laser light continuously oscillated from the laser medium rod 10 in multiple modes, and an oscillating laser light are externally provided. Sync signal S from
An acousto-optical forced mode-locking element 14 for forcibly synchronizing with 0 is arranged.

In the solid-state laser oscillation system shown in FIG. 1, the semiconductor laser 8 generates a laser beam having a wavelength optimum for resonantly exciting the medium of the solid-state laser medium rod 10, and this exciting laser beam is used. The light is condensed by the condenser lens system 9 into the solid-state laser medium rod 10 through the surface 10A as its reflection surface. As a result, the medium in the rod 10 is resonantly excited by the laser beam for excitation, and multimode laser light is continuously generated from the rod 10. The generated laser light propagates in the rod 10 between the surface 10A as a reflection surface thereof and the plane mirror 15, and is resonantly amplified during this period. The wavelength of the resonance-amplified laser light is limited to the etalon 12, is tuned by the acousto-optic Q-switch 13, and is externally given to the sync-switch 14 by the acousto-optic forced mode-locking switch 14. Synchronized to S0. Therefore, the plane mirror 15 outputs a single-mode pulse laser beam having a large peak power in synchronization with the synchronization signal externally applied to the synchronization switch 14.

[0012]

As described above, in the solid-state laser oscillation system of the present invention, since the excitation laser has the optimum wavelength for resonantly exciting the solid-state laser medium, the solid-state laser medium can be excited with high efficiency. Since the solid laser medium is not heated unnecessarily, the quality of the laser beam generated from the solid laser medium can be improved. Moreover, since the semiconductor laser is used as the excitation light source, the life of the solid-state laser oscillation system can be extended. Specifically, the solid-state laser oscillation system that employs a semiconductor laser is 1000
It is estimated to be operational for 0 hours.

The solid-state laser oscillating system of the present invention has a large peak power and is capable of oscillating a laser beam of good quality, and is therefore most suitable for a laser oscillator for nuclear fusion.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an optical system of a Kaizenger type solid-state laser oscillation system of the present invention.

FIG. 2 is a schematic diagram showing an optical system of a conventional Kaizenger type solid-state laser oscillation system.

[Explanation of symbols]

 8 ... Semiconductor laser 9 ... Condensing lens system 10 ... Solid laser medium rod 11 ... Concave reflecting mirror for astigmatism correction 13 ... Acousto-optical Q switch 14 ... Acousto-optical Forced mode-locking device 15: Laser output plane mirror

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 591114803 Laser Technology Research Institute Foundation 1-8-4 Tsutohoncho, Nishi-ku, Osaka City Osaka Prefecture Science and Technology Center Building (72) Inventor Sadao Nakai Kita, Ibaraki City, Osaka Prefecture Kasugaoka 3-chome 6-45 (72) Inventor Masahiro Nakatsuka 78, 1425 Midorigaoka, Ikoma-shi, Nara 78 (72) Inventor Masanori Yamanaka 3-chome, Ishimaru 3-chome, Minoh City, Osaka Prefecture E-205 (72) Inventor Kenta Naito 15 29 29, Ari-cho, Ikoma-shi, Nara (72) Inventor Masato Omi 1-6-5 Uenohigashi, Toyonaka-shi, Osaka (72) Chiyoe Yamanaka 1-8-4, Tsubomimoto-cho, Nishi-ku, Osaka Laser Technology Research Institute (72) Inventor Gen Onoda 1-20-1 Minamiikebukuro, Toshima-ku, Tokyo Kinmon Electric Co., Ltd. (72) Inventor Hiroshi Nakazato Nissin Electric Co., Ltd. 47 Umezu Takaunecho-cho, Ukyo-ku, Kyoto Prefecture

Claims (1)

[Claims] 1. A solid-state laser medium, a semiconductor laser for continuously supplying a pumping laser beam to the solid-state laser medium, an optical resonator for resonantly amplifying the laser beam generated from the solid-state laser medium, and an internal resonator. 2. A solid-state laser oscillation system comprising: a wavelength selection element for selecting a specific wavelength and a tuning synchronization optical means disposed in a resonator for tuning and synchronizing the oscillated laser light.