Jump to Content
chapter 4, Photon Transfer Theory
Chapter Contents
- 4.1 Photon Transfer Relation
- 4.2 Sense Node Sensitivities
- 4.2.1 Sense node sensitivity
- 4.2.2 Sense node to source follower sensitivity
- 4.2.3 Sense node to CDS sensitivity
- 4.2.4 Sense node to ADC sensitivity
- 4.3 Interacting Photon Sensitivities
- 4.3.1 Interacting photon sensitivity
- 4.3.2 Interacting photon to ADC sensitivity
- 4.4 Incident Photon Sensitivities
- 4.4.1 Incident photon sensitivity
- 4.4.2 Incident photon to ADC sensitivity
- 4.5 Photon Transfer General Derivation
- 4.6 Effective Quantum Yield
- 4.6.1 Photon event charge sharing
- 4.6.2 Charge collection efficiency
Excerpt
4.1 Photon Transfer Relation
A functional block diagram for a typical CCD/CMOS camera system is illustrated in Fig. 4.1. The system shown is described by the six transfer functions related to the semiconductor, pixel detector, and electronics that process the video signal. The input to the camera is expressed in units of the average number of incident photons per pixel (P), and the final output signal is given as the average DN encoded for each pixel. The output is related to the input gain relation
The signal and shot noise parameters at each point in the block diagram are listed in Table 4.2.
The gain functions contained in Eq. (4.1) are difficult to measure individually with good precision (<1% rms), especially those parameters related to the internal workings of the sensor. The PT method provides us with a solution to find the overall camera transfer function [Eq. (4.1)] accurately without knowing individual transfer functions. However, the PT technique is only fully applicable if a detector's response is shot noise-limited as explained below. Fortunately, this is the case for solid state sensors such as CCD and CMOS imagers.
©2007 Society of Photo-Optical Instrumentation Engineers
