A PHOTOSPECTROMETER REALIZED IN A STANDARD INTEGRATED-CIRCUIT PROCESS

A photospectrometer has been realized in a standard integrated circuit (IC) process. Only the masks, materials, and fabrication steps inhere nt to this IC process were used (i.e., no post processing to add mecha nical or optical devices for filtering). The spectrometer was composed of a set of 18 photodetectors with independent spectral responses. Th e responses of these devices were weighted and summed to form outputs proportional to the input optical power in discrete wavelength bands i n the region from similar to 400 to similar to 1100 nm. With the solut ion space restricted to a 60 nm band, this instrument could resolve Ga ussian input spectra (sigma = 5 nm) with a peak-to-peak spacing of les s than 15 nm. This device could easily be integrated with additional a nalog, digital, or wireless circuits to realize a true laboratory inst rument on-a-chip. (C) 1998 American Institute of Physics.