Patent US 11,645,856

A vehicular driver monitoring system includes a driver monitoring camera and an illumination source accommodated within a movable head of an interior rearview mirror of a vehicle. The illumination source is electrically controlled to modulate near-infrared (NIR) light emitted by the illumination source whereby NIR light emitted by the illumination source comprises a characteristic modulation signature. Ambient light that is present within the interior cabin of the vehicle and modulated NIR light emitted by the illumination source that is reflected off at least the head of the driver of the vehicle are incident at the imaging array sensor of the driver monitoring camera. Processing of captured image data at an image processor distinguishes (i) NIR light emitted by the illumination source that has the characteristic modulation signature and that is reflected off the head of the driver from (ii) ambient light present within the interior cabin of the vehicle.