JPH0458580A - Laser - Google Patents

Abstract

PURPOSE:To make it possible to double the intensity of laser output compared with that of one semiconductor laser by synthesizing laser light discharged from two semiconductor lasers with a polarization beam splitter and optically energizing YAG or amorphous crystal. CONSTITUTION:Optical semiconductor lasers 4 and 4' are laid out at a differential angle of 90 deg. and the laser light is arranged to enter a polarization beam splitter 5 to get synthesized by way of collimator lenses 3 and 3'. This synthesized laser light is adapted to enter YAG 1 where the YAG is optically energized. In this case, the semiconductor laser 4 is laid out so that it may become P polarization while the semiconductor laser 4' is laid out so that it may become S polarization when viewed from the polarization beam splitter 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser device for optically exciting YAG or nonlinear crystal using a semiconductor laser.

[Conventional technology]

The conventional YAG laser device, as shown in Fig.
An output mirror 2 is placed in front of the GI, and a semiconductor laser 4 is placed behind the GI with a collimating lens system 3 in between, forming a resonator between the output mirror 2 and the element 4a of the semiconductor laser 4, and emitting light from the semiconductor laser 4. The laser beam is incident on YAGl through a collimating lens system 3 to optically excite it.
The gain is proportional to the intensity of the semiconductor laser pumped until it is saturated.

Therefore, if the incident intensity of the semiconductor laser is increased, YA
The output of the G laser will also become stronger.

[Problem to be solved by the invention]

As explained above, the strength of the YAG laser can be increased by increasing the power of the semiconductor laser, but if you want to double the strength of the YAG laser, the price of the semiconductor laser used for that purpose will be more than ten times as expensive. This does not match profitability.

Therefore, the object of the present invention is to obtain a structure that is twice as strong and can be provided at a low cost.

[Means to solve the problem]

The present invention was made to solve the above problems,
Two semiconductor lasers are arranged with an angular difference of 90°, and their laser beams are made incident on YAG or a nonlinear crystal via a collimating lens system and a polarizing beam splitter.

[Effect]

Laser light emitted from two semiconductor lasers is combined by a polarization beam splitter to optically excite YAG or a nonlinear crystal, so the laser output intensity is doubled compared to the case of one semiconductor laser.

〔Example〕

FIG. 2 shows an embodiment of the present invention, in which semiconductor lasers 4.4'' are arranged with an angle difference of 90°, and the laser beams are sent to a polarizing beam splitter 5 through collimating lens systems 3 and 3', respectively. The synthesized laser light is made incident on YAGl to optically excite YAG.

Note that the semiconductor laser 4 is arranged so that it becomes P polarized light when viewed from the polarizing beam splitter 5, and the semiconductor laser 4' is set to S polarized light.
Install it so that the light is polarized.

According to the above structure, the intensity of the semiconductor laser incident on the YAGI is twice that of the case where one semiconductor laser is used, so the output of this laser device is doubled.

Figure 3 shows a different embodiment in which a collimating lens system is not provided between the semiconductor laser and the polarizing beam splitter, and one collimating lens system 3# is used instead of YAG.
This is provided between the polarizing beam splinter 5 and the polarizing beam splinter 5.

Due to the nature of the emitted light from the semiconductor laser, the arrangement of the collimating lens shown in Figure 2 is more natural and provides better performance. Performance similar to the example can be obtained.

Note that the configuration exemplified above can also be applied to a laser device in which YAGl is replaced with a nonlinear crystal, and similar effects can be obtained.

〔Effect of the invention〕

According to the present invention, it is possible to provide a laser device with twice the intensity of a conventional laser device using a semiconductor laser for optical excitation of YAG or nonlinear crystal at a price less than 1/10.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of a conventional device, and FIGS. 2 and 3 are diagrams each showing the configuration of an embodiment of the present invention. 1- -YAG 2...Output mirror 3.3", 3"...Collimating lens system 4.4°
...Semiconductor laser 5...Polarizing beam splitter patent applicant Nihon Kagaku Engineering Co., Ltd.
32; Same representative Osamu Hattori 1 ・ 2 ・ 3゛, 3゛・4, 4゛ ・5 ・ ・YAG ・Output mirror・Collimating lens system・Semiconductor laser-polarizing beam splitter

Claims (1)

[Claims] Two semiconductor lasers 4 and 4' are arranged with an angular difference of 90 degrees, and their laser beams are made incident on the YAG 1 or nonlinear crystal via the collimating lens system 3 and the polarizing beam splitter 5, and A laser device characterized in that the laser 4 is installed so that it becomes P-polarized light when viewed from the polarization beam splitter 5, and the semiconductor laser 4' is installed so that it becomes S-polarized light.