An apparatus and method are provided for manipulating light beams propagated through an optical apparatus that includes a planar lightwave circuit (PLC) and free-space optics unit. A multi-wave optical signal coupled to the PLC is propagated through a first and second waveguide array to generate a phased array output at an edge facet of the PLC. The phased array output at the edge facet is spatially Fourier transformed by the lens to generate a spectrally resolved image having a discrete light spot for each channel of the input optical signal, which is coupled to a pixelated optical receiving unit. When the optical receiving unit is a reflector, one or more of the discrete light spot are reflected to a desired waveguide array of a PLC to produce a desired output. When the optical receiving unit is a pixelated transmissive modulator, one or more of the discrete light spot are modulated as they pass through the modulator.