MICRO-EPSILON scanCONTROL2800, Инструкция по эксплуатации

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MICRO-EPSILON
X9751109-B060097MSC 29
If the target is extrem dark or has a high contrast MICRO-EPSILON recommends a prior
test. The various demonstration programs are suited for adjustment and test of the
illumination time. Operate with different illumination times and watch on the effect in the
charts.
The current illumination time can be calculated from the time stamp of the target profile
values. The demonstration program (see Fig. 8.1) shows the current illumination time in
the status line.
This function can be switched off on request.
8.3 Measuring Field Selection and Calibration
8.3.1 Measuring Field
The optical structure of the sensor is designed according to the so-called "Scheimpflug
condition" which ensures optimum imaging over the complete measurement range.
Here, the measurement range is formed on a square matrix. The distortions which arise
are illustrated in the following figures. The useful measurement range is always
trapezoidal.
The maximum x values assigned to the z coordinates are entered in Fig. 8.4 and 8.5.
More precise values can be taken from the sensor inspection log for your sensor.
The upper edge corresponds to the start of the measurement range and the lower edge
the end of the measurement range. The corners of the read-out image field are located
on a grid with a pitch of 128 pixels. A change of image field is only possible on this
pitch of 128 x 128 pixels.
The high resolution CMOS imaging matrix has 1024 x
1024 pixels and freely selectable access to predefined
areas. Consequently, the geometry of the measuring
field (height Z and width X) can be varied and can be
adapted to the measurement application. The
measuring field size is determined in the controller by
the measuring field register.
Example: The standard measurement range is located
in the center: Image field (Z x X) 768 x 512 pixels. The
measuring field value is determined by addition of the
row and column index (see Fig. 8.2 and Chap. 13.2).
Measuring field = 48 + 2 = 50. The associated
measuring fields are grey illustrated.
Other measuring fields and therefore measurement ranges are possible depending on
the set measuring field parameter. The possible
measuring field values with the
associated measuring fields are illustrated in Chap. 13.2.
Example: With a measuring field value of zero the complete matrix is evaluated and
with a measuring field value of "95" only an image field of 256 x 256 pixels in the center
is evaluated.
Fig. 8.2: Measuring
field "50"
Column index
Row
index
+0 +7
Fig. 8.3a: Measuring field "0" Abb. 8.3b: Measuring field "95"
0 88
Information for Operation