| 摘要 |
The infrared detector contains an emitter (4), a receiver (5) and an analysis circuit (2') having means (14 to 18) for obtaining a working signal (U n). The analysis circuit (2') contains a controller (29) for outputting a compensating signal (I k) superimposed over the incoming signal (I e), which on the one hand receives the working signal (U n) and on the other hand is connected to the output of the receiver (5), the compensating signal (I k) is selected so that the working signal (U n) is corrected to the value zero so that the maximum sensitivity is retained at all times. In a preferred embodiment, an analogue/digital converter (26, 30) is connected downstream of the controller (29), the analogue/digital converter (26, 30) on the one hand digitising the controller signal and on the other hand being connected to a digital/analogue converter (25, 32) for generating a voltage corresponding to the digital signal value in each case. This voltage determines the compensating signal(I k). |
