JAI TM/TMC-4200CL Manuale Utente
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Functions and Operations
TM/TMC-4200CL Series Progressive Scan Cameras
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. Since the CCD’s saturation voltage is 400 mV to 500 mV, it uses less than 1/5 of the full dynamic
range.
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. Since the CCD’s saturation voltage is 400 mV to 500 mV, it uses less than 1/5 of the full dynamic
range.
Machine vision and outdoor applications, cannot afford to miss image information behind the
saturation, which is why the dynamic range adaptation is critical.
saturation, which is why the dynamic range adaptation is critical.
6.5.1 Programmable Look-Up Table (LUT) and Knee Control
The TM-4200CL 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 12-bit A/D input so that the full dynamic range of the
CCD is utilized at 12-bit references as the input and the LUT output is converted into either 8-bit or 10-
bit to adjust the gamma correction. There is no 12-bit LUT.
(maximum level... saturation point) are set to 12-bit A/D input so that the full dynamic range of the
CCD is utilized at 12-bit references as the input and the LUT output is converted into either 8-bit or 10-
bit to adjust the gamma correction. There is no 12-bit LUT.
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.
segmented into three regions. The look-up table selection can be made by knee curve direct input.