Patent ID: 8314661

Claim:
An atomic oscillator using an electromagnetically induced transparency phenomenon caused by irradiation of a resonant light pair to an alkali metal atom, comprising: a light source that generates a first light having a center frequency f 1 and a first plurality of frequency components different from each other in frequency by Δf, and that generates a second light having a center frequency f 2 and a second plurality of frequency components different from each other in frequency by Δf; a light detection unit that detects intensities of lights including the first light and the second light passing through the alkali metal atom; and a control unit that controls, based on a detection result of the light detection unit, to cause a first frequency difference between a first specified frequency component of the first light and a second specified frequency component of the second light to be equal to a third frequency corresponding to an energy difference between two ground levels of the alkali metal atom, wherein a second frequency difference between the center frequency f 1 and the center frequency f 2 is different from the third frequency, and the first frequency difference is provided by selecting one of the following three combinations (1) through (3) of the first specified frequency and the second specified frequency: (1) the first specified frequency is other than the center frequency f 1 and the second specified frequency is other than the center frequency f 2 ; (2) the first specified frequency is the center frequency f 1 and the second specified frequency is other than the center frequency f 2 ; and (3) the first specified frequency is other than the center frequency f 1 and the second specified frequency is the center frequency f 2 .