Etalon De Fabry Perot 644 Nm

For optical filtering and generation of interference rings in the experiment to demonstrate the normal Zeeman effect. The fixed etalon consists of a substrate with highly reflective, if only partially reflecting, mirror coatings on both sides. The substrate and mirrors form an optical resonator which fulfils the resonance conditions for a specific wavelength of 643.8 nm, which is that of the red cadmium line. The inclination of the etalon to the optical axis can be adjusted by means of adjustmen