Patent ID: 7734128

Claim:
A wavelength selective switch comprising: a fiber collimator array including a fiber array in which a plurality of optical fibers containing an optical fiber corresponding to an input port and optical fibers corresponding to output ports is arrayed and a microlens array in which microlenses are arrayed on a transparent substrate in positions corresponding to the plurality of optical fibers, and the fiber collimator array collimating a wavelength division multiplexed optical signal input to the optical fiber corresponding to the input port by the microlens corresponding to this optical fiber, to output the collimated wavelength division multiplexed optical signal; a spectral element for spectrally separating the wavelength division multiplexed optical signal output from the fiber collimator array according to wavelengths; a condenser element for condensing optical signals of respective wavelengths spectrally separated by the spectral element on different positions; and a mirror array including a plurality of mirrors disposed on the condensing positions of the optical signals of respective wavelengths, and the mirror array outputting the optical signal reflected by each mirror from any one of the optical fibers corresponding to the output ports via the condenser element, the spectral element and the fiber collimator array, wherein, in the fiber collimator array, each microlens and the transparent substrate are oppositely arranged so that a plurality of projections formed on a bottom face of each microlens intersects with a plurality of projections formed on a surface of the transparent substrate, and each microlens and the transparent substrate are adhered to each other by an adhesive.