P. Banerji et al., SETTING UP OF A PHOTON COUNTER WITH FEEBLE LIGHT FROM LIGHT-EMITTING-DIODES, Indian Journal of Pure & Applied Physics, 32(10), 1994, pp. 849-851
Light emitting diodes (LEDs) of different colours operated at low curr
ents have been used as sources of feeble light for setting up of a pho
ton counter. The intensities of light emitted from these LEDs have bee
n measured with a photomultiplier tube (PMT) as a function of current
through them. The light emitted from the red and green LEDs over a cur
rent range 50 muA to 6 mA are found to be linear. Therefore, these LED
s are best suited for setting up of a photon counter.