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  • sCMOS sensor technology

  • PCO is Pioneer in sCMOS image sensor technology. Read more about our PCO`s sCMOS cameras and get an insight in sCMOS knowledgebase.
    • sCMOS – General Information

    • PCO sCMOS cameras are a breakthrough in scientific camera development by combining the advantages of CCD and CMOS technology in a single device. The lowest readout noise, wide dynamic range, and fast frame rates all at high resolution are achieved at the same time with the very compact camera head.
    • Pixel Size

    • In a popular misconception it is assumed that the larger the pixel size the better the sensitivity. However it is pixel architecture and electronic layout which have a crucial influence on the pixel sensitivity. The unique design of the square 6.5 μm sCMOS pixel allows for very high full well capacity, a large light sensitive area; and an extremely low readout noise. Furthermore the 6.5 μm pixel size has proven in the past the highest versatility in adapting to the resolution requirements of most applications, like special microscopy setups.
    • Quantum Efficiency (QE)

    • The QE value of a sensor indicates the percentage of incoming photons generating a photo electron. An ideal sensor would achieve 100% QE. All our pco.edge series cameras are based on two similar sCMOS sensor designs exceeding 60% or even 82% QE. In addition the pco.edge 3.1 and 5.5 models are available as color sensor versions using high quality RGB Bayer filters.
    • Full Well Capacity

    • This is the maximum usable amount of electrons which a single pixel can hold before recombination and other non linear effects have to be considered. In relation to their pixel size of 6.5 μm, sCMOS pixels excel with a surprisingly high full well capacity of ~30.000 electrons, which is a prerequisite for the huge dynamic range provided by these sensors.
    • Dynamic Range

    • The contrast between the brightest and the weakest measurable light signal in the same image defines the „intra-scene“ dynamic range of a sensor. Whereas the full well capacity sets the upper limit for the brightest signal, it is effectively the readout noise which sets the lower detection limit. With the sCMOS values of ~30 000 electrons full well and around 1 electron rms readout noise, signal-to-noise can range from 88.6 - 92.0 dB, depending on camera choice.
    • Binning

    • In general, no conventional physical binning at the charge carrier level (as on CCDs) is possible with CMOS image sensors because the charge to voltage conversion already happens on each individual pixel. Summing up the voltage values of neighboring pixels means also summing up the noise attributed by that conversion. Although doing so increases the SNR, the effect is less advantageous than summing up the primary charge carrier packages of neighboring CCD pixels. Scientific CMOS cameras from PCO offer as standard binning modes all combinations from H1xV1 to H4xV4.
    • Dark Signal Non-Uniformity (DSNU)

    • PCO cameras deliver a very homogeneous and stable dark image which is beneficial especially in low light applications. DSNU is defined as the spatial signal variation between pixels without illumination. One of the main causes for these variations are slight differences between the individual column amplifiers. DSNU values measured for all of the pco.edge cameras according to EMVA 1288 standards are well below 1 e- rms.
    • Photon Response Non-Uniformity (PRNU)

    • Differences in the behavior of the column amplifiers affect not only the dark image but also the illuminated image, e.g. by column to column variation of the amplifier gain. A quantitative measure for pixel to pixel variations caused by these variations is the PRNU value as defined in EMVA 1288 standard. PRNU values measured for all pco.edge sCMOS cameras are below 0.5%, indicating that neighboring pixel differ less than 0.5% in their reaction to the same light signal.
    • Linearity

    • For most measurement applications it is very convenient to have a linear response of the output signal to changes in light input. Deviations from such a linear behavior are addressed as non-linearity. All pco.edge cameras employ the necessary electronic components and firmware algorithms to correct the non-linear behavior in real time providing for linearity > 99%.
    • Water-Cooling

    • A high-grade water-cooling system is available providing vibration-free operation with an extremely stabilized sensor temperature and fast cooling operation. If you use more than one camera, PCO’s powerful water cooler can easily operate four pco.edge cameras. Furthermore, operation with fan cooling is still possible without the water cooled component.