| 摘要 |
PURPOSE: To reduce variation in characteristic due to temperature variation by fixing a ferrule holder which supports an optical fiber to a package at positions that are symmetrical about >=2 planes containing the optical axis of emitted light of the light emitting element. CONSTITUTION: In this light emitting element module, an isolator holder 10 is fixed to the package 11 by spot welding at four points F1 -F4 symmetrical about two planes P1 and P2 containing the optical axis of projection of the light emitting element. Namely, the welding points F1 and F3 are symmetrical about the vertical plane P1 containing the optical axis of projection of the light emitting element and the welding points F2 and F4 are symmetrical about the horizontal plane P2 containing the optical axis of projection of the light emitting element. Therefore, even when the package 1 thermally expands, the isolator holder 10 and the optical axis of projection do not change in relative position and the shift of the optical axis due to the thermal expansion is caused only by the displacement of the isolator due to the thermal expansion of the isolator holder 10. |
