Patent ID: 6927636

Claim:
An atomic frequency standard, comprising means for providing a controlled emission of D transition light; a resonant microwave cavity for receipt of the controlled emission of D transition light, including a transparent gas cell containing an atomic gas in the path of the emission of D transition light, a light sensor for sensing the intensity of the D transition light transmitted through the atomic gas and providing a light-intensity signal, and means for injecting microwave energy into the microwave cavity, said microwave cavity being resonant at about the hyperfine transition frequency of the atoms of said atomic gas; and an electronic assembly including means for generating a standard frequency and, from said standard frequency, a microwave frequency that is frequency-modulated about the hyperfine transition frequency of said atomic gas for injection into said microwave cavity, said electronic assembly being connected with said light intensity signal and developing from said light intensity signal, an error signal applied to said means for generating a standard frequency to lock said standard frequency to the hyperfine transition frequency of the atomic gas, said electronic assembly further including an algorithm relating the light intensity signal to ambient temperature at the time of manufacture of the atomic frequency standard and an input representing ambient temperatures that may affect the emission of D transition light, and providing an output developed from said algorithm, said output representing ambient temperature and said light intensity signal, for correcting the controlled emission of D transition light to substantially eliminate changes due to light intensity aging.