A METHOD AND APPARATUS FOR MEASURING THE FREQUENCY OF RADIATION

摘要

Method and apparatus for measuring the frequency of radiation comprising a pair of filters (2, 3) or a beam splitter (30) responsive to radiation from a source of radiation (4) for providing a first output having a magnitude which increases and a second output having a magnitude which decreases with an increase in the frequency of said radiation, a divider (11) for providing a ratio of the magnitudes of said first and second outputs and a comparator (14) and memory (17) responsive to the ratio from said divider (11) for providing an output corresponding to the frequency of said radiation.