US 12,381,367 B2
Laser amplifier
Yukari Miyagi, Tokyo (JP); and Kenichi Hirosawa, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
Filed on May 27, 2021, as Appl. No. 17/332,632.
Application 17/332,632 is a continuation of application No. PCT/JP2019/000233, filed on Jan. 8, 2019.
Prior Publication US 2021/0288460 A1, Sep. 16, 2021
Int. Cl. H01S 3/063 (2006.01); G02B 27/09 (2006.01); H01S 3/23 (2006.01)
CPC H01S 3/063 (2013.01) [G02B 27/0972 (2013.01); H01S 3/2308 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A laser amplifier comprising: a planar optical waveguide for laser amplification; and an input optical system to input signal light to a core layer of the planar optical waveguide,
wherein the input optical system includes:
a collimating lens to convert output light from a signal light source into parallel light;
an anamorphic prism to convert output light from the collimating lens into parallel light having a reduced beam width in a first direction; and
a cylindrical lens to collect output light from the anamorphic prism in a second direction, and
output light from the cylindrical lens is input to the core layer, as the signal light having been collected in the second direction and to be propagated inside the core layer without changing the beam width in the first direction, and wherein
the planar optical waveguide has a laminated structure including an upper clad layer, the core layer, and a lower clad layer,
the first direction is set to be orthogonal to a lamination direction in the laminated structure,
the second direction is set to be parallel to the lamination direction in the laminated structure, and
in a side face of the core layer, an antireflection film is provided for a portion to which the signal light is input or a portion from which the signal light is output, and a high reflection film is provided for another portion of the side face.