#### Using Optical Calibration Standard Certification Data

During the optics calibration of a vision probe, if a certification data file (fovcert.dat) exists in the probe directory, PC-DMIS will read the file and use it to adjust the calibration data from the nominal. A fovcert.dat file supports data for the X and Y size of the concentric rectangles and for the X and Y center positions of the concentric circles.

In the table below, the left column contains a sample nominal fovcert.dat file:

2 [PATTERN] 0xAA [RECTANGLES] ;X size Y size

17.2 13.2

10.75 8.25

6.45 4.95

4.3 3.3

2.15 1.65

1.29 0.99

0.86 0.66

0.5375 0.4125

0.3225 0.2475

0.215 0.165

0.1075 0.0825

0.043 0.033

[CIRCLES]

; nom diam centerx centery

30 0.0 0.0

20 0.0 0.0

10 0.0 0.0

5 0.0 0.0

2.5 0.0 0.0

1.25 0.0 0.0

0.625 0.0 0.0

0.25 0.0 0.0

Information about the fovcert.dat File

- The first line must be the file schema number.

- A semicolon at the start of a line denotes that the line is a comment.

- Comment lines may not start with a space character.

- The [PATTERN] value is a hex bitmask denoting the rectangle edges to be measured in X and Y. The position of the edges is from left to right and from top to bottom. For example, a value of 0xAA hex is 1010 1010 binary. This translates to use the first and third edges in the X direction and the first and third edges in the Y direction for rectangle measurement.

- All values are in mm.