Abstract: A dual pyroelectric crystal sensor suitable for infrared intruder alarms and the like having two separate closely spaced identical pyroelectric crystal detectors connected in parallel opposition. The sensor includes a single ended field effect transistor amplifier with the entire sensor encapsulated in a TO-5 can. The two crystals each have one end cemented to a ceramic substrate in a cantilevered fashion, permitting shock or vibration to affect each crystal equally. Therefore, voltages due to the piezoelectric responses of the crystals are equal and cancel. If both crystals are irradiated by a common heat source, the pyroelectric generated voltages will cancel. If either crystal is irradiated separately, an output voltage will be produced.

Abstract: A pyroelectric detector comprising a wafer of pyroelectric material, means for collecting electrical charge indicative of energy absorbed by the wafer, electrical means for removing and processing the collected charge, a base defining at least one supporting surface, and a flexible suspension for supporting the wafer in spaced relation to the supporting surface. The suspension includes a plurality of link elements each in the form of a thin metal wire fixed to the supporting surface and to a surface of the wafer and located around the periphery of the wafer. Each link preferably has a shape like an arch with both ends fixed to the supporting surface and the wafer surface fixed to the arch between the ends thereof. The link elements have sufficient strength to hold the wafer in spaced relation to the supporting surface, and the links have sufficient flexibility to absorb shock and vibration forces and to compensate for different coefficients of thermal expansion of said wafer and said supporting surface.

Abstract: A pyroelectric detector comprising a wafer of pyroelectric material, means for collecting electrical charge indicative of energy absorbed by the wafer, electrical means for removing and processing the collected charge, a base defining at least one supporting surface, and a flexible suspension for supporting the wafer in spaced relation to the supporting surface. The suspension includes a plurality of link elements each in the form of a thin metal wire fixed to the supporting surface and to a surface of the wafer and located around the periphery of the wafer. Each link preferably has a shape like an arch with both ends fixed to the supporting surface and the wafer surface fixed to the arch between the ends thereof. The link elements have sufficient strength to hold the wafer in spaced relation to the supporting surface, and the links have sufficient flexibility to absorb shock and vibration forces and to compensate for different coefficients of thermal expansion of said wafer and said supporting surface.