Timing Alignment
The coordination of a flash pulse with the active exposure interval of an image sensor ensures that the illumination is fully captured within the frame duration. Achieving accurate strobe synchronization prevents the appearance of dark bands or uneven brightness across the captured image area. This alignment is necessary when using high-speed flash sources for scientific imaging or industrial inspection.
Shutter Coordination
In sensors utilizing rolling shutters, the flash must occur during the short window of time when all rows are open at once. If this strobe synchronization fails, the flash will only illuminate a portion of the image, leaving other rows in darkness or underexposed. This timing window is often very narrow, requiring microsecond-level precision from the trigger system.
This coordination becomes more difficult as the sensor readout rate increases or when the pulse width of the flash is shortened.
Drift Phase
Thermal drift in the controller electronics can shift the trigger timing over time. This phase shift causes the flash to occur outside the optimal exposure window.
Verification Testing
To test the accuracy of the timing, technicians monitor both the camera exposure output signal and the optical pulse using a dual-channel oscilloscope. Adjusting the trigger delay compensation based on these measurements guarantees that the peak output of the light source occurs exactly in the middle of the integration window. This step is repeated at different frame rates during system calibration.
