JPS61151437U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
FIG. 2 is a circuit diagram showing one embodiment of the detection circuit in FIG. 1, FIG. 3 is a block diagram showing another embodiment of the detection circuit in FIG. 1, and FIG. 4 shows the detailed configuration of FIG. 3. The circuit diagrams shown in Figures 5 and 6 are
FIG. 3 is a waveform diagram for explaining the operation shown in the figure. 1... Light emitting element, 2... Optical fiber, 3... Reflection plate, 4... Half mirror, 5... Light receiving element, 6
...Detection circuit, 60, 65...Differential amplifier, 61
...DA converter, 62, 63...Comparator,
64...Shift register, 66...Analog switch, 67...OR circuit, r...Feedback resistor.

Claims (1)

[Scope of utility model registration request] A light source, an optical fiber, a light-receiving element, a reflector whose reflectance for incident light varies in multiple stages depending on the operating position, and a reflector plate disposed between the light source and one end of the optical fiber to reflect light from the light source. The light is incident on the reflective surface of the reflective plate disposed at the other end of the optical fiber via the optical fiber, and the reflected light that has been reflected from the reflective surface and passed through the optical fiber is incident on the light receiving element. A multi-stage optical switch comprising a half mirror and a detection circuit that detects the operating position of the reflector based on the output of the light receiving element and sends the detection result as a switch output.