Semiconductor laser device and optical apparatus

Patent metadata

Field	Value
Publication number	US-2022209508-A1
Application number	US-202117559239-A
Country	US
Kind code	A1
Filing date	Dec 22, 2021
Priority date	Dec 24, 2020
Publication date	Jun 30, 2022
Grant date	—

Abstract

A semiconductor laser device includes: a substrate having a main surface; a first cladding layer with a first conductive type and a second cladding layer with a second conductive type, which are stacked over the main surface of the substrate; and a light-emitting layer that is formed between the first cladding layer and the second cladding layer, and is formed on a first surface parallel to the main surface of the substrate; the light-emitting layer has a plurality of light-emitting regions emitting laser beams in a red range; and among the laser beams emitted from the light-emitting regions, the difference between a peak wavelength in an optical spectrum of at least one laser beam and a peak wavelength in an optical spectrum of the other laser beams is 1.5 nm or more.

First claim

What is claims is:

1 . A semiconductor laser device comprising:
a substrate having a main surface; a first cladding layer with a first conductive type and a second cladding layer with a second conductive type, which are stacked over the main surface of the substrate; and a light-emitting layer that is formed between the first cladding layer and the second cladding layer, and is formed on a first surface parallel to the main surface of the substrate; wherein the light-emitting layer has a plurality of light-emitting regions emitting laser beams in a red range; and among the laser beams emitted from the light-emitting regions, the difference between a peak wavelength in an optical spectrum of at least one laser beam and a peak wavelength in an optical spectrum of the other laser beams is 1.5 nm or more.

2 . The semiconductor laser device according to claim 1 , wherein the light-emitting layer emits a laser beam having a wavelength of 600 nm or more and 700 nm or less.

3 . The semiconductor laser device according to claim 1 , wherein the semiconductor laser device has at least three light-emitting regions.

4 . The semiconductor laser device according to claim 1 , wherein among the laser beams emitted from the light-emitting regions, the difference between the peak wavelength in the optical spectrum of at least one laser beam and the peak wavelength in the optical spectrum of the other laser beams is 3 nm or more and 30 nm or less.

5 . The semiconductor laser device according to claim 1 , wherein among the laser beams emitted from the light-emitting regions, the difference between the peak wavelength in the optical spectrum of a laser beam having a longest wavelength and the peak wavelength in the optical spectrum of a laser beam having a shortest wavelength is 1.5 nm or more and 30 nm or less.

6 . The semiconductor laser device according to claim 1 , wherein the light-emitting regions are spaced apart with an interval of 5 μm or more and 100 μm or less between the light-emitting regions adjacent each other.

7 . The semiconductor laser device according to claim 1 , wherein each of the laser beams emitted from the light-emitting regions has a spectral linewidth of 0.01 nm or more and 1 nm or less.

8 . The semiconductor laser device according to claim 1 , wherein each of the laser beams emitted from the light-emitting regions has a spectral linewidth of 0.0001 nm or more and 0.01 nm or less.

9 . A semiconductor laser device comprising:
a substrate having a main surface; and a plurality of light-emitting regions that are formed over the main surface of the substrate, and emit laser beams having a wavelength of 600 nm or more and 700 nm or less; wherein among the laser beams emitted from the light-emitting regions, the difference between a peak wavelength in an optical spectrum of at least one laser beam and a peak wavelength in an optical spectrum of the other laser beams is 1.5 nm or more; the laser beams have spectral widths that are expanded by applying a current superimposed with a high frequency current to the light-emitting regions; and the laser beams emitted from the light-emitting regions are projected to a projection part through a waveguide.

10 . An optical apparatus comprising:
a semiconductor laser device; a drive circuit that drives the semiconductor laser device by applying a current to the semiconductor laser device; a high frequency superimposition circuit that is connected to the drive circuit; a waveguide that guides a laser beam emitted from the semiconductor laser device; and a projector part to which the laser beam guided through the waveguide is projected; wherein the semiconductor laser device comprises a plurality of light-emitting regions that are formed over a substrate and emit the laser beams having a wavelength of 600 nm or more and 700 nm or less; among the laser beams emitted from the light-emitting regions, the difference between a peak wavelength in an optical spectrum of at least one laser beam and a peak wavelength in an optical spectrum of the other laser beams is 1.5 nm or more; and the laser beams have spectral widths that are expanded by superimposing a high frequency current on the current by the high frequency superimposition circuit.

Assignees

• Ushio Electric Inc

Inventors

• Hagimoto Masato
• Okumura Tadashi
• Inoue Yutaka

Classifications

• G03B21/2033

  LED or laser light sources · CPC title

• H01S5/343 Primary

  in AIIIBV compounds, e.g. AlGaAs-laser {, InP-based laser} · CPC title

• H01S5/32325

  red laser based on InGaP · CPC title

• H01S5/34326

  with a well layer based on InGa(Al)P, e.g. red laser · CPC title

• H01S5/4012

  Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms · CPC title