| 摘要 |
PROBLEM TO BE SOLVED: To realize a photosensor element, esp., such element having a Darlington transistor type structure which has a high power, high collector-emitter breakdown voltage providing a high withstanding voltage, and low base-emitter resistance providing a low internal resistance. SOLUTION: This photosensor element has a photoelectric converter 4 and Darlington-connected transistors 1 and 2 at a first and output stages to amplify a photo current provided by the converter 4. The output stage transistor 2 of the Darlington connection has a higher amplification factor than the first stage one 1 and dark current limiting resistor 4 is inserted between the base and emitter of that transistor 2. |
