Design of a dispersion interferometer on a field-reversed configuration device

Dispersion interferometry (DI) is a promising method for density measurement. Compared with the traditional interferometer, the DI is immune to mechanical vibration and can avoid the fringe jump error. In addition, a simple optical configuration is also one of the advantages of the DI. The electron density of the Huazhong University of Science and Technology field-reversed configuration (HFRC) device can reach 1020 m−3 with a pulse length of 50 µs. In this case, the DI based on the CO2 laser on the HFRC device adopts the heterodyne technique based on the acousto-optic modulator, which can increase the temporal resolution to 40 MHz. It can realize density fluctuation measurements in the MHz range. The test of each optical element, especially the nonlinear crystal, has been completed. The AgGaSe2 crystal can produce a second harmonic wave of about 52.5 µW when the incident CO2 power is 10 W. Based on these designs and tests, a DI system can be expected on the HFRC device.