PURPOSE: To reduce a stray noise by making the optical axis of an incident laser beam and inside surfaces of the recessed part of an optical element almost parallel.
CONSTITUTION: In a semiconductor laser device provided with an optical element 11 having a recessed part whose inside surfaces become almost parallel with the optical axis or the part, a semiconductor laser chip 1 and a light receiving element 3, the semiconductor laser chip 1 and the optical element 11 are arranged so that the optical axis of the laser beam 13 emitted from the semiconductor laser chip 1 and the optical axis of the optical element 11 almost coincide. Then, since the parts made to be incident on the inside surfaces of the optical element having the recessed part among the laser beam from the semiconductor laser chip 1 are reflected to directions going out to the outside of the semiconductor laser device, the parts are prevented from being made incident on the light receiving element 3.
NAKANISHI HIDEYUKI
UENO AKIRA
YOSHIKAWA AKIO
| JPH0344992A | 1991-02-26 | |||
| JPS6362257A | 1988-03-18 | |||
| JPS63197361A | 1988-08-16 |
Next Patent: FORMATION OF OPTICAL WAVEGUIDE TYPE DIFFRACTION GRAIN