Patent ID: 7372031

Claim:
A system for generating a photon sensor signal in response to a number N photons per unit time received over a first area from a photon event comprising: an optical amplifying device receiving the number N input photons per unit time over the first area and generating a number M output photons per unit time with a gain K 1 defined as a ratio of M to N; wherein the optical amplifying device further comprises a photon gathering device for collecting N 1 photons over a second area and focusing the N 1 photons over the first area, wherein the photon gathering device has an optical gain K0 defined as the ratio of the second area to the first area and KO is a factor of K 1 ; and a photon detecting device receiving the M output photons per unit time and generating the photon sensor signal with a gain K 2 defined as a ratio of a level of the photon sensor signal to a corresponding level of M, wherein the system has performance parameters including a system gain K as the product of K 1 and K 2 .