CPC A61B 5/02427 (2013.01) [A61B 5/0042 (2013.01); A61B 5/0075 (2013.01); A61B 5/6826 (2013.01); G01J 1/44 (2013.01); G01J 2001/446 (2013.01)] | 12 Claims |
1. A light-to-digital converter, comprising:
a light-to-current converter;
a current integrator with an integrator output resettable to a baseline value;
and a counter with a digital output, wherein:
said light-to-current converter is arranged to be connected as a positive integration input to said current integrator during a light-collecting phase, said current integrator integrating a current resulting from light-to-current conversion at said light-to-current converter, said integrator output starting from said baseline value and ending at a value to be digitized;
a reference current source is arranged to be connected as a negative integration input to said current integrator during a counting phase subsequent to said light-collecting phase, integrating a reference current from said reference current source, said integrator output starting from said value to be digitized and ending at said baseline value, a time spent integrating said reference current corresponding to said value to be digitized; and
said counter is configured for measuring said time and outputting a count corresponding to said value to be digitized.
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