Abstract

A commercial internal mirror 543 nm He-Ne laser was locked on the saturated absorption spectra (R(12)26-0 and R(106)28-0 transition in the ${\text{X}}^1{\Sigma }_{\text{g}}^{+}{\text{-B}}^3{\Pi }_{0\text{u}}^{+}$ series) of iodine. A polarization flip of the laser was suppressed by using the transverse magnetic field from 0.01T to 0.02T. Thus frequency tuning without the polarization flip throughout one mode separation was made possible. The external absorption-cell (30 mmϕ × 500 mm) with the cold finger was made of fused silica, and the temperature of the cold finger was guaranteed to be within ± 0.01°C around 0°C which corresponds to the vapor pressure of 4.7 ± 0.003 Pa⁽¹⁾. Actuator for frequency control of laser was provided with both components of fast and slow. The fast actuator was realized using a piezo electric transducer (PZT) through an elastic deformation of the laser tube, and frequency fluctuation actuator as drift was controlled through the slow components which consisted of the film heaters rounded on the laser tube. Laser frequency was also modulated through the fast control loop.

© 1995 IEEE