PI miCos GmbH - CA-1200 HeNe Laser

Measurements and Handling

1.) Output power versus laser tube current

An open frame gas laser consisting of a HeNe tube with brewster windows and separate resonator mirrors is used for demonstration and teaching of the basics of gas lasers like stability, coherence and mode behavior. learn more ...

2) Optical stability area of the resonator

The output power of the HeNe laser is measured as a function of the resonator length. When exceeding the stability range of the cavity the laser operation brakes down. Measurements with mirrors of different curvature and different resonator configurations can be performed and compared with theoretical calculations.

3) Extra and Intra cavity beam profile

Using a caliper gauge the beam diameter as a function of the position inside the resonator is evaluated. Different resonator types can be tested and compared with theoretical calculations.

4) Output power versus laser tube position

Within this measurement the position of the laser discharge tube is varied and its influence on the relative output power is determined.

5) Mode structures

By slightly missaligning the cavity mirrors of a spherical resonator mode structures of higher orders than TEM00 can be achieved.

6) Single mode operation with etalon (full version)

Single mode Etalon with adjustment holder. The Etalon has a diameter of 12,7 mm and a thickness of 10 mm. Higher orders can adjusted by tilting one of the adjustment screws of the etalon holder 9.
To check out if the laser is running in single mode, an external fabry perot interferometer is required.

7) Wavelength selection with birefringent filter (full version)

A disc of natural birefringent quartz is mounted in an rotator unit which allows the tuning of different wavelength in the laser system.
If the birefringent filter is rotated in small angles around chosen main line you can get 4 additional wavelengths with different gains. A provided optical grating allows to distinguish the different wavelengths via their different diffraction angles. By Bragg's law the wavelengths can be calculated.

8) Wavelength selection with Littrow prism (full version)

A high quality ‘Littrow’ prism is provided for laser wavelength selection.

9) Infrared wavelength operation (optional)

This feature is optional available (CA-1205) to the educational kit.
The set consists of two laser mirrors which are coated for infrared operation of the laser. The adjustments are similar to adjustments for the visible operation. All measurements (except of Littrow prism) mentioned before can also be done with infrared configuration.