The EMVA 1288 is the Standard for Measurement and Presentation of Specifications for Machine Vision Sensors and Cameras. The sensor is the heart of a camera and therefore its most important component. A sensor consists of pixels with photodiodes that convert energy of the incoming photons to an electrical charge which is then converted and processed to generate an image. Sensor or camera properties are described with different parameters (EMVA Standard 1288)
Quantum Efficiency (QE) [%]
The incident photon to converted electron ratio is called quantum efficiency. The QE depends on the wavelength of the light. The bigger the number of electrons produced
by a given number of photons, the higher the QE and the more information is available in an image. A high quantum efficiency is especially important in low light conditions.
Temporal Dark Noise [e-]
Even if no light hits the sensor, some electrons are captured by pixels and create a signal that is called dark noise. Those electrons result from the electronics that surround the sensor. The less dark noise, the better the signals can be detected.
Saturation Capacity [ke-]
The number of electrons a pixel can hold is limited and set by the saturation capacity. In a saturated pixel no more photons can be converted into electrons and thus image information is lost.
Dynamic Range [dB]
The ratio between maximum and minimum measurable light intensities is described as dynamic range. A high dynamic range is especially important when there are both dark and bright details in an image, or when light conditions are changing. Details such as barcodes, labels or the fill level can be inspected more accurately.
Signal to Noise Ratio (SNR) [dB]
The SNR compares the level of a desired signal to the level of background noise.