Broadcom AFBR-S50, Быстрый старт

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Broadcom AFBR-S50-EK-UG102
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AFBR-S50
User Guide Evaluation Kit Quick Start Guide
2.4.1.3 Crosstalk Calibration
Crosstalk (Xtalk) calibration is suggested to be carried out for each system design with implemented AFBR-S50 sensors. It
targets to compensate electrical crosstalk possibly generated by the application PCB, as well as optical crosstalk generated
by a cover glass mounted above the sensor and therefore affecting its optical path.
Calibration Steps at a Glance
1. Xtalk (shaded) calibration with shaded sensor → electrical Xalk will be compensated.
2. Xtalk (without coverglass) calibration on low reflective target suggested is a black foam as target, for example,
https://www.dpv-elektronik.de/Packaging-Storage-systems/Packaging/Foams/
The intention is to measure against infinity; however, this is not feasible indoors. Thus a highly, low reflective target is used.
3. Xtalk (with coverglass) calibration with black foam as the target and cover glass in front of the sensor.
Final Crosstalk for each pixel is then calculated by the following formula.
Example Calibration Sequence for Electrical Xtalk Compensation Only
1. Blind the sensor with a foam while taking measurements, and make sure that the amplitudes are roughly as low as shown
in the following figure.
Figure 39: Blinding Sensor for Xtalk Calibration
2. Click
Run Crosstalk Calibration Sequence
located in the
API
tab.
Figure 40: Crosstalk Calibration Amplitude
The Xtalk vector table is immediately applied to all pixels. For further information, refer to the information in the cover glass
calibration guide.
Xtalk(total) = Xtalk(shaded) – Xtalk(w/o coverglass) + Xtalk(with coverglass)
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