Automation Technology C5-1280CS14-120, Руководство пользователя

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C5-CS Series User Manual Rev. 1.6  33
Subpixel Limitations
The range values of the 3D sensors are limited to 16bit which result to possible values
between 0 and 65535. Setting the subpixel value to 6 correspond to a factor of 2^6 = 64.
If the laser line appears at a sensor row higher than #1023 (with 6 subpixel) will result in a
bit overflow. For example: laser line at row #1500 -> 1500 x 2^6 = 96000.
Therefore it can be necessary to use a lower subpixel value to avoid a bit overflow. The
table below shows the maximum subpixel value in compare to the used number of rows
and the laser line appearance on the sensor ship without bit overflow. The subpixel value
in the factory configuration is always set to fit the complete Z-Range on the sensor chip
without overflows.
0 1 2 3 4 5 6
1023
      
2047
      
3072
      
Nevertheless it is still possible to use a higher subpixel value even when the laser line
appears on a sensor row >#1023. In that case make sure that the defined AOI is smaller
or even 1023/2047 rows and that the flag AbsOffsetPos (Camera Control -> Mode and
Algorithm Control -> AbsOffsetPos) is set to false. Then the offset position with respect to
the start row of the AOI is returned and thus the laser line can appear on sensor rows
>#1023.
With the release of the new C5-1280CS models some new features were implemented
based on the SFNC 2.3 standard as well as some AT specific features.
One new feature is the Mono8 mode in 3D line mode to reduce the amount of acquired
data to be able to increase the maximum profile frequency. This reduction leads to a
specific set up which is described in the table below.
0 1 2 3 4 5 6
3
      
7
      
15
      
31
      
63
      
127
      
255
      
Using number of rows with a higher subpixel accuracy then stated in the table above can
result in a bit overflow. That happen easy, when the pixel values go over the 8 Bit (2^8 - 1
= 255) range.
More details regarding the operation of the C5-1280CS sensor can be found
in a separate application note.