THORLABS WFS Series, Руководство по эксплуатации

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© 2007-2012 Thorlabs GmbH
70 WFS Series
Note: Changing the camera resolution will also change the number of detectable
spots. In case you are working with a 'User Calibrated Reference' a new User
Calibration
may be required.
Depending on the selected camera resolution in pixels the resolution of the
Wavefront Sensor, that is the number of the calculated microlens spots is also
defined thereby. The number of microlens spots in x and y direction are as follows:
WFS Camera
resolution in pixel
Wavefront resolution Wavefront points
WFS150x WFS300x WFS150x WFS300x
320 x 320 7 x 7 3 x 3 49 9
512 x 512 13 x 13 5 x 5 169 25
768 x 768 21 x 21 9 x 9 441 81
1024 x 1024 29 x 29 13 x 13 841 169
1280 x 1024 37 x 29 17 x 13 1073 221
WFS10 Camera
resolution in pixel
Wavefront resolution Wavefront points
WFS10-5C
WFS10-7AR
(150 µm pitch)
WFS10-14AR
(300 µm pitch)
WFS10-5C
WFS10-7AR
(150 µm pitch)
WFS10-14AR
(300 µm pitch)
180 x 180 9 x 9 3 x 3 81 9
260 x 260 15 x 15 7 x 7 225 49
360 x 360 21 x 21 9 x 9 441 81
480 x 480 29 x 29 13 x 13 841 169
640 x 480 41 x 29 19 x 13 1189 247
The wavefront resolution is by the factor microlens pitch / pixel size lower than the
camera resolution. This means about 32x32 CCD pixels are mapped to one single
microlens (WFS150x). For WFS10 instruments with 150 µm lenslet pitch only about
15x15 CMOS pixels are mapped to one microlens.
Image Averages
Averages will reduce measurement noise which can be advantageous in case a low-
level light source has to be analyzed. An average setting higher than 1 will take
multiple images from the camera, average the pixel intensity pixel by pixel and output
an averaged image to the following evaluating routines. Due to reduced intensity
noise the accuracy of detected spot centroids is increased.
The available average settings are
95