Optical filter

Abstract

Abstract PURPOSE:To increase the quantity of attenuation by attaching a dielectric multilayer filter between the one end of a forcusing light transmitting element and a rectangular prism reflector and make incident light transmit into the dielectric multilayer filter twice. CONSTITUTION:A dielectric multilayer filter 2 and a rectangular prism reflector 3 are attached to the one end 13 of a forcusing light transmitting element 1 with 1/4 pitch whose refractive index changes according to the square of the distance from the center axis and the tops of optical fibers 41 and 42 for input/output are arranged close to the other end 12. Almost all the light signals included in the transmission wavelength area of the light made incident from the optical fiber 41 into the focusing light transmitting element 1 passes through the dielectric multilayer filter 2 and is made incident to the optical fiber 42 after being transmitted through the same passage. The light signals included in the rejecting wavelength area are relfected by the dielectric multilayer filter 2 and projected from the position other than the optical fiber 42, so that these signals are not bonded to the optical fiber 42 in principle.

Inventors

• 👤 Takeshi Usui

Bibliographic Details