| 摘要 |
PURPOSE:To obtain a filter with less stroke light due to absence of an undesired optical output by connecting an input optical path an the output optical path of the filter to the input output guide path of the same side of an array guide path lattice optical multiplexer and demultiplexer and connecting a reflected optical path having an optical switch to the input output guide path opposite to the optical multiplexer and demultiplexer. CONSTITUTION:A 1st input output guide path group 23 and a 2nd input output guide path group 27 use respectively an array guide path refraction grating optical multiplexer and demultiplexer 21 comprising 16-sets of guide paths whose frequency multiple number is 16. Then an input optical path 1 and an output optical path 2 are connected in guide path pairs in the 1st input output guide path group 23 of the array guide path refractive grating type optical multiplexer and demultiplexer 21, a reflected optical path 28 is connected to each guide path pair in the 2nd input output guide path group 27 and optical switches 9a, 9c, 9e, 9g, 9i, 9k, 9m, 9o are interposed respectively on the way of each reflected optical path 28. Thus, a structure is adopted that an optical signal received from the input optical path 1 is not directly outputted to the output optical path 2. |
