THORLABS BC207UV, Руководство по эксплуатации

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BC207 Series
Chapter 5: The Graphics User Interface (GUI)
Rev: 8.1, 10-Jan-2022
Page 36
© 2022 Thorlabs
Then define the ‘Min. Image Saturation’ level in %, that will be the software controlled bright-
ness trigger level.
A default value of 50 % indicates that only images with a half scale maximum brightness are
triggered, captured and interrogated afterwards. Dark images taken by the camera with a maxi-
mum brightness lower than the selected ‘Min. AD Saturation’ level will be ignored and not dis-
played.
Adjusting Exposure Time and Gain
Adjust both the ‘Exposure Time’ and the ‘Gain Factor’ controls so that a low ‘AD Saturation’ (in
% of full scale brightness) results when no laser pulse is captured. Increase the ‘Exposure
Time’ and ‘Gain Factor’ so that a detected laser pulse exceeds the ‘Min. AD Saturation’
threshold. Decrease both controls in case the detected pulse reaches the limiting 100% satura-
tion because its real intensity may be considerably higher.
The status bar informs you about the activated software trigger function.
The Beam Profiler is waiting for an image reaching the selected saturation threshold. In case
the actual AD saturation level is below the threshold, the status bar informs you about a waiting
software trigger event.
For frequently occurring pulses it is recommended to set the Exposure Time to a slightly shorter
period than the pulse period so that only a single pulse is captured.
Prevent ambient light from entering the input aperture and use one of the neutral density filters
for its attenuation.
Note that the image brightness of a captured single optical pulse is not adjustable by the ‘Ex-
posure Time’ control in case the single optical pulse is shorter than the adjusted exposure dura-
tion. Use the supplied ND filters of the filter wheel and the ‘Gain Factor’ control to adjust image
brightness. In order to ensure a minimum noise level it is recommended to keep the gain value
as low as possible.
3. Single Pulse
This option allows to use an external electrical TTL trigger input from a pulsed light source to
synchronize image capturing with single pulses.
1) Please feed the TTL level trigger signal from the laser source or from the appropriate driving
pulse generator into the BNC connector of the BC207 Series device.
Attention
Be sure to enter only a TTL compatible signal to the BNC jack not exceeding the
range between 0.0 V and +5.5 V. Higher or lower voltages may damage the trigger in-
put. See section
Trigger Input for details.
The TTL Trigger input parameters are listed in the table below:
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