Abstract
We have constructed a portable iodine-stabilized 543 nm He-Ne laser using the saturation spestroscopy and the third harmonic locking technique. From the signal-to-noise ratio, the noise-limited-stability would be better than 8.5x10-12 for integration time longer than one second. There are three major parts in our laser system: (1)laser box; (2)optics box and TE cooler controller; and (3)electronics. We tried our best to make the structure of the laser system simpler and smaller. For instance, we changed the cooling system of the I2 cell from water-cooling to air-cooling, and got rid of the water pump. We recommended the hyperfine b10 component of R(106)28-0 as the wavelength standard. In our system, the reference of frequency stabilization is b10.