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TM-6760 Series Progressive Scan Shutter Cameras
Operation
• Variable positive knee curve and negative knee curve
• Direct input LUT and negative LUT
3.8 Programmable LUT and Knee Control (patent pending)
The TM-6760 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 are converted into 8-bit data to adjust the gamma correction.
The look-up table has two knee points (variable gamma selection) that allow the 10 bits to be
segmented into three regions. The look-up table selection can be made either by variable knee curve or
by direct input of the knee coordinates.
256
224
192
160
128
96
64
32
0
128 256 384 512 640 768 896 1024
Knee
Tabl e
0
1
2
3
4
5
6
7
LUT #7
LUT #3
LUT #5
LUT #4
LUT #6
LUT #0
Left Knee
(X1, Y1)
84 224
56 224
80 160
60 160
40 160
96 192
48 192
112 224
Right Knee
(X2, Y2)
1024 256
1024 256
1024 256
1024 256
1024 256
1024 256
1024 256
1024 256
Note: The second knee point on the built-in LUT defaults to position (1024, 256).
To reposition this point, click on it and drag it to a new location.
LUT #1
LUT #2