| 摘要 |
PURPOSE:To improve the profitability by making an optical demultiplexing optical system for constituting an optical demultiplexer, or an output use optical fiber movable, so that optional optical signals whose number is smaller than N pieces can be selected, among N pieces of optical signals whose wavelength has been multiplexed. CONSTITUTION:N pieces of optical signals whose wavelength has been divided and multiplexed, from an input use optical fiber 1 pass through a lens 4, hit against a grating element 5, reflected therein by changing an angle at every wavelength, and one optical signal among them is condensed by a lens 5 and made incident on an output use optical fiber 2. In this state, by rotating the grating element, it becomes possible to make an optical signal of other wavelength incident on the optical fiber 2. Generally, as for the number of optical fibers 2, M pieces being smaller than N are provided, and by a means for rotating the grating element 3, optional M pieces of optical signals, among N pieces of signals can be made incident on the optical fiber 2, and the profitability can be improved. |
