selfoc lens
A selfoc lens is a converging lens that bundles the diverging light rays of an optical fiber for a detector. In a conventional lens, the light undergoes refraction at the transition between air and glass, changing the direction of the light rays hitting the glass surface. The situation is different with the Selfoc lens, where the refractive index in the lens is different.
In the Selffloc lens, the incident light is uniformly and continuously deflected toward the focal point by gradual density changes equal to that of the gradient index.
The selfoc lens is much simpler in design than a conventional microlens and can have a required refractive index through controlled density changes. The refractive index changes are achieved by a high-temperature process in which ions diffuse into the material.
Selfoc lenses are used in fiber optics. They are located in front of or on top of the O/E converter and concentrate the light beams onto the optical detector.
The designation Selfoc lens is a trademark of the Nippon Sheet Glass Company.