A scanning projector for projecting an image comprising a plurality of wavelength signals (i.e., light signals having different wavelengths) is disclosed. Embodiments of the present invention comprise a beam combiner comprising a planar lightwave circuit that includes a plurality of surface waveguides arranged to define a plurality of input ports, a mixing region, and an output port. Different wavelength signals received at the input ports are combined into a composite output beam that is scanned over a region. The projector (1) scans a first wavelength signal over a plurality of image points in the region, (2) detects an amount of the first wavelength signal reflected from each image point, whose reflectivity at the first wavelength is based on a measure and, and (3) projects an image onto the region using a second wavelength signal, where the image is based on the reflected first wavelength signal at each of the image points.