What Is a Fiber Unit?
A fiber unit is an optical cable section in which light is irradiated using the phenomenon of total reflection of light within the fiber, which forms a double-layered structure with a core with a high refractive index and a cladding with a low refractive index covering the core. It is also called an optical fiber.
In general, fiber units are used to detect various objects as photoelectric sensors that enable the detection of objects by light irradiation by combining a fiber unit that irradiates light while passing it through it with a fiber amplifier that has a light source and an optical amplification function.
Applications of Fiber Units
A fiber unit is a fiber cable equipped with a small sensor head. Generally, a fiber unit is not used by itself but is used in combination with a fiber amplifier equipped with a detection mechanism to enable detection.
Fiber units and fiber amplifiers are widely used in various production sites for non-contact general product detection, detection and positioning of extremely small products in narrow spaces, liquid level detection in storage tanks, and other applications.
Principle of Fiber Unit
Fiber units are optical cables characterized by the fact that light is irradiated using the phenomenon of total reflection of light within the fiber, which forms a double-layered structure consisting of a central core with a high refractive index formed thinly mainly of quartz glass or plastic, and a cladding with a low refractive index covering the surrounding area.
This fiber unit is available in two types: a glass type using quartz glass for the core and a plastic-type using acrylic resin. The quartz glass type is heat resistant, while the plastic type is lightweight and breakage-resistant, and can be matched to the detection environment.
In addition, since the light irradiated from the fiber unit end face spreads at an angle of approximately 60 degrees when the fiber unit’s optical cable is used alone, the purpose of changing this irradiation angle and light collection rate, as well as protecting the fiber unit end face and fixing the fiber unit end face, are also served. A sensor head is also attached to the end face of the fiber unit to protect and fix the end face of the fiber unit.
The fiber unit with these features is used as a fiber sensor by connecting two fibers, one on the light emitting side and the other on the light receiving side, to the light source of a fiber amplifier. A wide range of detection is made possible by the transmission type, reflection type, retro-reflection type, limited reflection type detection methods, and various sensor head shapes.