A robust, inexpensive wavelength meter using a commercial color sensors

Commercial color sensor chips are used in a variety of consumer electronics.~ Many are built to specifications far above those needed for their typical uses, some having temperature coefficients of only a few parts per million, and using precision 16 bit analog to digital converters.~ Using such a device, we were able to measure the wavelength of a laser with a precision of 0.01 nm with a calibration drift of similar magnitude over several days.~ Factors that influence the precision and accuracy, such as etalon effects in the sensor, temperature dependence, intensity variations, and timing, will be discussed.