To provide a circuit for photodetection, and a photodetector capable of measuring a quantity of light over a wide dynamic range by using a PMT.
The circuit 2 for photodetection is provided with a voltage application means 21 for apply a predetermined potential gradient to a photocathode 33 and n stages of dynodes Dy1-Dyn, and a first changeover means 23 for switching the potential gradient between the dynode Dy1 and the dynode Dy2 over to a potential gradient reverse to it. With respect to light to be detected L having a smaller light quantity, the switching means SW1 of the changeover means 23 is turned disconnected. On this occasion, secondary electron multiplication of photoelectrons generated at the photocathode 33 is performed by the dynodes Dy1-Dyn, and an output current I1 is taken out from an anode 37. With respect to light to be detected L having a larger light quantity, the switch SW1 is turned connected. On this occasion, photoelectrons generated at the photocathode 33 are taken out from the dynode Dy1.
SUZUKI YASUAKI
| JPS6444557U | 1989-03-16 | |||
| JPH06150877A | 1994-05-31 |
Shiro Terasaki
Satoru Ishida