Mitsubishi Denki Kabushiki Kaisha

Junichiro Yamashita

Eiichi Nakagawa

Masatoshi Suzuki

Shigeyuki Akiba

Takeshi Nakamura

Katsumi Satoh

Koji Goto

Tadayoshi Kitayama

Kuniaki Motoshima

Kazunori Taguchi

Naoki Norimatsu

Toshio Takei

Haruo Abe

Yoshio Miyake

A light trigger thyristor including a light guide (30) held in a receiving metal fitting (11) with a light entering end side of the light guide (30) inserted into one end of a cylindrical sleeve (15). A plano-convex lens (17) is inserted into the other end of the cylindrical sleeve (15) to face a light introducing window (LW). A connector terminal (12) to which step index optical fibers (131, 132) are connected is attached to the metal receiving fitting (11). The light triggering thyristor prevents light from leaking out a bending portion of the light guide (30) to increase the transmission efficiency of light signals, prevents breakdown of the thyristor element due to concentration of the light signals even when light signals entering the light guide (30) are provided through a plurality of optical fibers from a plurality of light sources, and decreases optical loss due to misalignment of the optical axis of the optical transmission system without requiring very accurate adjustment to the relative position of the optical fibers (131, 132) and the light guide (30).

Light trigger thyristor

A light amplifying apparatus adopting a redundant structure. Optical isolators 13, 14 are inserted between pump light sources 1, 2 and a photocoupler 4 so as to prevent injection locking, thereby preventing fluctuation of pump power. In another embodiment, optical fibers 15 adequately longer than the coherence length of the excitation light waves output from the pump light sources are provided. In still another embodiment, the frequency of the driving current for the pump light sources is modulated. In a further embodiment, wave plates 20, 21 are provided so as to circularly polarize the light waves output from the pump light sources clockwise and counterclockwise.

Light amplifying apparatus

A novel optoelectronics package includes an optical semiconductor, an electronic cooling element carrying the optical semiconductor and electrically connected to one of the terminals thereof, a pair of transmission lines having distributed constant characteristics and an airtight vessel housing the optical semiconductor, cooling element and transmission lines. A grounding line of the transmission lines is connected between the terminal of the optical semiconductor and an external ground terminal fixed at the vessel. A signal line of the transmission line is connected between the other terminal of the optical semiconductor and an external signal terminal, whereby the stray capacitance of the cooling element is shorted by the distributed constant grounding line.

Optoelectronics package

In an optical coupling unit having an optical coupler adapted to couple a light beam from a light-emitting element to an optical fiber, the aberration of the lens is decreased to improve the efficiency of coupling of the light beam from the light-emitting element to the optical fiber. A silicon crystal having a high refractive index is used as a lens material to realize an optical system of low aberration.

Optical coupler

Growing community of inventors

Kanagawa, Japan

Junichiro Yamashita