The new method is based on short interuptions of the LED supply, to capture the forward voltage of the LED at low current condition. During the interuption a small capacitance is discharged over the LED to supply the measurment current.
Because this interuption can be kept very short it does not interfere with flicker video imaging even when using a slow rate of measurements.
When using a slow rate the dimming should be performed by current dimming having a fixed duty cycle.
When using high frequency rates like 1 kHz the dimming nor the temp sensing does lead to flicker when taking a movie.
The effect is shown in the video below!
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