Distance at which a change of signal is produced with axial approach of the object.
Optical fibers are suited for many applications:
Optical fibers made of glass or plastic are used to pipe light from the sensor to the object and back. They are passive components of a photoelectric system. Because of their passiveness and the absence of moving parts, light can be piped in hazardous areas. They are also immune to electromagnetic interference. The glass or plastic core of the fibers is sheathed. The sheath has a lower refractive index than the core. The law of total internal reflection defines,when a light beam hits the medium boundary between two media with different refractive index, it is totally reflected, provided the angle of incidence does not exceed a determined critical angle.
Opposed mode sensors consist of emitter and receiver mounted in separate housings. They are installed directly opposite each other in such a way that the light from the emitter is aimed directly at the receiver. When an object interrupts or weakens the light beam, the sensor switches. Opposed mode sensors are the most reliable photoelectric sensors for detection of opaque targets.
Off‐state current (lr)