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In current digital cameras, sensors are arrays of photodiodes which "transform" photons energy to electrons. I am aware that the probability of a photon to generate an electron is modeled by a Poisson distribution. However, I can not find any precise information on how the hit point of a photon on the sensor surface will be measured depending on its position :

  • Does the energy measured on a given photodiode (which is a finite surface) depends on the distance from the center of the surface to the photon impact point?

  • I can imagine that a photon hitting the surface generate energy which propagates in space (isn't it?). Can this "energy area" be modeled? For example (this is why I ask this question), how much energy is received by a neighbor photodiode when a photo hit another photodiode.

An answer with detailed equations or reference to academic publications will be greatly appreciated.

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