This part is a kind of semiconductor called LHI778.

Function of this product has Dual Element Detector.

Manufacturers : PerkinElmer Optoelectronics

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Lighting | Imaging | Telecom Pyroelectric Infrared Detectors Dual Element Detector TO-5 housing Competitive cost version Designed for motion control The LHi 778 pyroelectric infrared-detector series are the standard dual element design recommended for all variants of motion control. They include a dual element pyro-electric ceramic element with Fet in source follower connection. LHi 778 detector is available in TO-5 housing with standard infrared filter. It provides high responsivity with excellent common mode performance (match) and low noise at steady state and temperature changes. Parameters min Element size R esponsivity Match Noise Offset Voltage NEP Right for modification reserved / WS /, 27.4.2001 p LHi 778 D A T A S H E E T LHi 778 typical 2x1 3 300 4000 1 20 0,2 7,5x10- [ ... ]

LHI778 PDF Datasheet Download