LIGHT REFLECTING/TRANSMITTING ELEMENT AND OPTICAL AMPLIFIER USING THE SAME ELEMENT

摘要

PROBLEM TO BE SOLVED: To realize a light reflecting/transmitting element not having an infinitesimal ripple and a wavelength dispersion and an optical amplifier using the same. SOLUTION: The light reflecting/transmitting element comprises a three- terminal light band separation filter having one input terminal and first and second output terminals, and a total reflection terminator connected to the first or second output terminal. In this element, a desired signal light of a first band in a wavelength multiple signal light incident from the input terminal is transmitted to the first or second output terminal of the side not connected to the total reflection terminator and output. A residual second band signal light except the desired signal light incident from the input terminal is constituted to take a first operating state in which the second band light is reflected on the input terminal or a second operating state in which the desired signal light of the first band is reflected on the input terminal and the signal light of the second band is transmitted to the first or second output terminal of the side not connected to the total reflection terminator.