Patent attributes
An optical apparatus is disclosed wherein increase of the number of wavelength selective switches provided for a standby system can be suppressed. The optical apparatus includes a plurality of upstream side optical devices and a plurality of downstream side optical devices configured such that a plurality of output ports to be set as output destinations of light from a plurality of input ports can be changed over for each wavelength. An upstream side standby switch connected at a plurality of inputs thereof individually to the input ports and can change over an output of light from the inputs for each wavelength. A downstream side standby switch is connected at an input thereof to the output of the upstream side standby switch and at a plurality of outputs thereof individually to the output ports and can output light from the input to the plural outputs thereof.