The utility model relates to the technical field of instruments, and discloses an anti-
fog automatic instrument, which comprises an instrument sealing shell, the rear side surface of the instrument sealing shell is connected with a back plate, and a
measuring instrument is adhered to the back plate; the front end of the instrument sealing shell is connected with a window frame. An observation window adheres to the inner side face of the window frame. A
power controller is arranged on the rear side of the bottom in the instrument sealing shell, and one end of the
power controller is connected with the observation window through a wire. A rotating wheel is slidably arranged in the front end of the instrument sealing shell, and a worm engaged with the rotating wheel is arranged at the bottom of the rotating wheel; a water mist cleaning
assembly and a dust cleaning
assembly used for cleaning the inner wall and the outer wall of the observation window are installed at the circle center of the rotating wheel. Through the water mist cleaning
assembly, the dust cleaning assembly and the power supply controller, demisting, dust removing and deicing functions of the instrument observation window are achieved, the
instrument data observation view field is improved, and the problem that the measurement data observation view field of a traditional instrument glass observation window is not good due to water mist, dust and
frost is solved.