PURPOSE: To provide a small and highly sensitive pressure sensor excellent in environment resistance.
CONSTITUTION: A pressure sensor 20 is arranged so as to face an opening 14 communicated with a space 12 being a measuring object, and the pressure sensor 20 is provided with an airtight vacuum chamber formed of a cylinder 22 and a pressure receiving diaphragm 26. A field emission type cold cathode device 28 is arranged on the pressure receiving diaphragm 26. The cold cathode device 28 is provided with a large number of emitter electrodes 34 arranged in a matrix shape to emit electrons and a gate electrode 28 to p' extract the electrons. Two anode electrodes 44 and 46 are arranged on an inside end surface of the cylinder 22 so as to be opposed to the cold cathode device 28. The anode electrodes 44 and 46 are connected to a differential amplifier 48 to amplify a change in the distribution of output from respective ones.
NAKAMOTO MASAYUKI
KOHAMA MASAO
MASUMOTO HIROSHI
