The
right Sensor at the right time
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 Scientific
CCD wafer undergoing test and evaluation. After the wafer probe, the
wafer is diced and packaged for final shipping.
In scientific applications, low noise, high sensitivity, large dynamic range and high sensor resolution are dominant considerations. Scientific cameras can come with 12, 14 or even 16 Bit Analog to Digital Converters (ADC) to make use of the full range. Sensor array linearity and the ADC linearity over the full dynamic range are important. Low noise means low dark current and low read noise. The dark current can be controlled with cooling, and long integration times can increase the signal without impacting the noise levels. Low light level cameras have many applications, but they tend to be used for scientific applications. There is no set definition of "low light level" image sensor. One manufacturers define it as a sensor that can provide a usable image (SNR > 2) when the lighting conditions are less than 1 Lux. (Please see the lighting chart for an indication of 1 Lux background levels). Although Adept's CMOS sensors provide usable images at lighting levels down to 10mLux, the scientific back illuminated CCDs are capable of delivering useful images down to 0.1mLux. In other words, the scientific CCDs still hold a 100X advantage in image sensitivity. In a market where sensor performance is the dominant consideration, we do not believe that CMOS has developed to a point where it is competitive for the ultra low light levels. For applications requiring performance in the range of >10 mLux, Adept's CMOS image sensors are an ideal choice. Our proprietary designs provide for very high linearity (>99.5%), ultra-low cross-talk (<2% to nearest neighbor), PRNU's under 1% and FPN under 0.2%. Temporal noise is below 15e- rms for custom pixels. Patent pending low power on-chip ADC architectures provide resolutions up to 14 Bits at video rates for image sizes up to 1.3 Megapixels. Adept CMOS is the clear choice. |
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