A NTCDA single crystal is used as a photoelectric current multiplier
layer, and Au thin films are formed as electrodes on the opposite
surfaces of the multiplier layer by a vapor deposition method to form a
sandwich type cell. When a voltage is applied to the NTCDA single crystal
by the electrodes from a dc power source and a monochromatic light is
applied, a multiplied photoelectric current flows between the electrodes.
A rise of this element at light-on is considerably faster than when a
vapor-deposited layer is used as a photoelectric current multiplier layer
to permit a faster response.