To measure the functionality of PMD sensors with SBI circuitry, a phase measurement procedure must be used .
This is due to the fact that the total number of collected and stored electrons is modified by the usage of an active SBI, and so the standard definition of contrast (equation 4.1 ) can no longer be used as characteristic device performance parameter. To examine the achieved dynamic range (with regard to tolerable signal and background in tensity levels), a real ( Time-Of-Flight) phase measurement using a 4 -phase algorithm is performed under controlled conditions
(equation 4.2).