| 摘要 |
PURPOSE:To prevent deformation caused by an optical part by forming a smooth reference surface on a base member, and abutting one end of the optical part on this reference part to attain supporting. CONSTITUTION:A beam splitter 9 is composed of a parallel plate-like half mirror, and supported by a spring member 10. on the base member 2, in a state where one end part of the beam splitter 9 is inserted into a recessed part 11. The spring member 10 is composed of a base part 18 whose length is almost the same as the length from the opening surface of the recessed part 11 to its back surface, and width is almost the same as an interval between two side surfaces 16 and 17 of the recessed part 11, and a spring part 19 which extends backward from one side edge of the base part 18 and whose tailing edge is bent to obtain a J-shape. The side surface 16 of the upper side of the recessed part 11 is formed so as to obtain 45 deg. angle with respect to both of the optical axes of a laser diode 5 and a photodiode 7, and the beam splitter 9 is pressed on the side surface 16, so that the attached state of the beam splitter 9 is regulated by using the side surface 16 of the upper side of the recessed part as the reference part. |
