Continuous-wave terahertz digital holography of 3THz quantum cascade laser
Continuous-wave terahertz digital holography system has been established using 3THz quantum cascade laser. Holograms with no object located in the object beam path are recorded sequentially in air and vacuum conditions. Comparison between the two holograms illustrates that hologram retrieved in vacuum exhibits high quality and contrast. Besides, characteristic parameters of the laser beam focused and collimated in the system are interpreted in detail as well.