Tuesday, December 6, 2016

Quantum Efficiency and Microscopy Cameras

Microscope cameras and the importance of quantum efficiency.
Quantum efficiency (QE) is the measure of the effectiveness of a camera imager to produce an electronic charge from incident photons. In non-scientific terms it is a measurement of how efficient the camera is at capturing available light. The higher the number, the better the microscope camera is at this function.

When light is digitized photons pass through a camera sensor and are converted to electrons. Before the light is digitized they are stored as pixels. The number of electrons that are stored is referred to as "saturation capacity." Extra electrons are discarded once capacity is reached. QE is the percent of photons that are converted to electrons at a particular wavelength through the sensor.

So what exactly does this mean in terms of microscopy cameras? Typically microscope cameras with a higher quantum efficiency will perform better in low-light conditions. A new way to improve quantum efficiency is through a back illuminated sensor. Jenoptik is using back-illuminated sensors in their new line of Gryphax cameras. Back illumination means the sensor is back-thinned and light is delivered from the back making it easier for incident photos to reach and be absorbed in the active layer of the sensor.

A few of the microscope cameras with higher quantum efficiency include:
Microscopy image captured with the Jenoptik Arktur back-illuminated microscope sensor.
Microscopy image captured with the Jenoptik Gryphax Arktur back-illuminated sensor.