| 摘要 |
PURPOSE:To decrease the number of parts, to use the title device even at a narrow wavelength interval and to stabilize the connection with a fiber by using a diffraction grating composed of unequal interval curves for a wave- length demultiplexing element. CONSTITUTION:The title device is equipped with a wavelength demultiplexing element 2 to multiplex light signals from light sources whose wavelengths are different or branch a light signal composed of many wavelengths into the light signals of the wavelengths. The diffraction grating composed of the unequal curves is used for the wavelength demultiplexing element. That is to say, the title device has a function to demultiplex the light signal emitted spreadingly from a fiber 3 by a curve grating like the external circumstance part of a Fresnel lens and converge them to optical fibers 4 corresponding to the wavelengths. Conversely, when the light signals whose wavelengths are different are emitted from the fibers, all the light signals can be connected to one optical fiber. Thus, it can be used at the narrow wavelength interval with a simple structure and the connection with the fiber is stabilized. |
