Green laser optical module

Abstract

A green laser optical module includes a pumping laser, a solid-state laser, and a second harmonic generator. The pumping laser generates excitation light. The solid-state laser is excited by the excitation light and generates first light in an infrared wavelength band. The second harmonic generator converts the first light into second light in a green wavelength band and includes at least two polarization converting regions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a graph for explaining a change in the output characteristic of a second harmonic generator with a change in the ambient temperature;

FIG. 2 is a block diagram of a green laser optical module according to the present invention;

FIG. 3 illustrates a second harmonic generator of FIG. 2;

FIG. 4 is a graph for comparing a conventional second harmonic generator and a second harmonic generator according to the present invention;

FIG. 5 is a graph for explaining the operation characteristic of a second harmonic generator according to temperature; and

FIG. 6 is a view for explaining wavelength conversion of a second harmonic generator.

Claims

1. A green laser optical module comprising: a pumping laser which generates excitation light;a solid-state laser which is excited by the excitation light and generates first light in an infrared wavelength band; anda second harmonic generator which converts the first light into second light in a green wavelength band and includes at least two polarization converting regions.

2. The green laser optical module of claim 1, wherein the pumping laser is a Fabry-Perot laser.

3. The green laser optical module of claim 1, wherein the excitation light uses a wavelength band of 808 nm.

4. The green laser optical module of claim 1, wherein the second harmonic generator comprises KTiOPO4 (KTP) that includes the polarization converting regions.

5. The green laser optical module of claim 4, wherein two or more consecutive ones of said at least two polarization converting regions are respectively spaced apart by intervening one or more regions other than those comprising said at least two polarization converting regions.

6. The green laser optical module of claim 4, wherein said at least two polarization converting regions are interleavingly arranged on the second harmonic generator.

7. The green laser optical module of claim 4, configured such that a path of light generated by the green laser optical module passes, in series, through the at least two polarization converting regions.

8. The green laser optical module of claim 1, wherein the second harmonic generator comprises PPMgOLN that includes the polarization converting regions.

9. The green laser optical module of claim 8, wherein two or more consecutive ones of said at least two polarization converting regions are respectively spaced apart by intervening one or more regions other than those comprising said at least two polarization converting regions.

10. The green laser optical module of claim 8, wherein said at least two polarization converting regions are interleavingly arranged on the second harmonic generator.

11. The green laser optical module of claim 8, configured such that a path of light generated by the green laser optical module passes, in series, through the at least two polarization converting regions.

12. The green laser optical module of claim 1, wherein the pumping laser comprises a single-frequency laser.

13. The green laser optical module of claim 1, wherein two or more consecutive ones of said at least two polarization converting regions are respectively spaced apart by intervening one or more regions other than those comprising said at least two polarization converting regions.

14. The green laser optical module of claim 1, wherein said at least two polarization converting regions are interleavingly arranged on the second harmonic generator.

15. The green laser optical module of claim 1, configured such that a path of light generated by the green laser optical module passes, in series, through the at least two polarization converting regions.