Brightness detection device and electrical / electronic device therewith

Abstract

A brightness detection device is presented, comprising a brightness sensor H and an LED controlled by a control unit C via pulse width modulation, wherein the LED is arranged in a housing. A special feature is that the control unit C has a pulse width modulation signal PWMS with a switch-on time T_on per cycle corresponding to the LED being illuminated and a switch-off time T_off per cycle corresponding to the LED being off, wherein the brightness sensor H performs a brightness measurement during the switch-off time T_off corresponding to the LED being off, so that the LED does not contribute to the result of the brightness measurement, wherein the LED and the brightness sensor H are arranged at the common end GE of an optical fiber L having another end AE.

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