The invention discloses a controllable terahertz wave attenuator device and a method. The device is that a computer is connected respectively with a D / A converter and a two-dimensional moving platform, the D / A converter is connected with a
direct current high voltage amplifier, a terahertz wave source device, a
chopper, a piece of focusing lens, a
high resistance silicon, a piece of focusing lens, a terahertz wave
detector, a locking phase
amplifier, an A / D converter, and the computer, the high-resistance
silicon is connected respectively with an
argon ion laser and the two-dimensional moving platform. The method is that lasers which are issued by the
argon ion laser are used by the controllable terahertz wave attenuator device to excite photo-generated carriers; terahertz
waves can be decreased through the absorbing effect of the photo-generated carriers to the terahertz
waves. The controllable terahertz wave attenuator device of the invention has large decrement, smooth attenuating spectra
ray, compact structure, convenient adjustment, low cost, and can satisfy the requirements of the terahertz
waves for applying in the fields of imaging,
medical diagnosis, safety check, information communication, space
astronomy, and the like.