JAI PULNiX TM-4100GE, Руководство по эксплуатации

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Operation
TM-4100GE Hardware
A typical CCD camera does not use the full dynamic range due to the nominal gain and the output
specification such as RS-170. The typical CCD camera’s gain is set at 16 to 22 dB and the RS-170 video
level is 714 mV. Using 20 dB gain for the calculation, CCD output is limited to 714/10 = 71.4 mV.
Machine vision and outdoor applications cannot afford to miss image information behind the saturation,
which is why the dynamic range adaptation is critical.
8.7.1 Programmable Look-Up Table (LUT) and Knee Control
The TM-4100GE has a built-in LUT (look-up table) for dynamic range control. At a specific gain
setting, the offset (minimum level.... dark point) and A/D reference top voltage (maximum level...
saturation point) are set to 10-bit A/D input so that the full dynamic range of the CCD is utilized at
10-bit references as the input and the LUT output is converted into 8-bit to adjust the gamma correction.
Notice that the LUT (look-up table) is not available in the 10-bit grayscale mode.
The look-up table has two knee points (variable gamma selection) that allow the 10-bit input to be
segmented into three regions. The look-up table selection can be made by knee curve direct input.