Patent ID: 7521660

Claim:
An optical signal processor for subjecting light to processing according to a wavelength of the light, and outputting the processed light, said optical signal processor comprising: an input port for taking out the light to be processed; an output port for outputting the processed light; a first optical system for receiving the light fed into said input port and outputting the received light; a first wavelength branching device for inputting the light outputted from said first optical system, spatially splitting wavelength components included in the light, and outputting the split wavelength components to optical paths different from each other; a second optical system for converging the wavelength components outputted from said first wavelength branching device; a modulating part for spatially modulating an amplitude or phase of the wavelength components converged by said second optical system, and outputting the modulated wavelength components; a third optical system for receiving the wavelength components outputted from said modulating part and outputting the received wavelength components; a second wavelength branching device for inputting the wavelength components outputted from said third optical system, multiplexing the wavelength components, and outputting the multiplexed light; optical path turning means for turning an optical path of the light outputted from said second wavelength branching device, so as to output the light from said output port by way of said second wavelength branching device, said third optical system, said modulating part, said second optical system, said first wavelength branching device, and said first optical system in succession; and a monitor part disposed at a position different from positions where said input port and said output port are disposed, said monitor part monitoring, after receiving a part of the light directed from said second wavelength branching device to said optical path turning means, a spectrum of the received light or a power of a specific wavelength component in the received light.