“If there is a match for the various data such as the width of the mouth, length of the nasal ridge and distance between the eyes then the device will be unlocked,” said Osram, which has released a 940nm IR led for facial illumination – dubbed Synios P2720.

This wavelength is longer than has been usual. “It reduces the red glow that can occur with short-wave infra-red light sources,” explained the firm. “Up to now, the sensitivity of IR cameras was only good if the light source had a wavelength of 850nm. The cameras have been further developed to give them greater sensitivity in longer wavelength ranges so 940 nm light sources can now be used.”

Output of the device is 1,150mW at 1A – and 360mW/sr at an unspecified current.

Footprint is 2.0 x 2.75mm, x 0.6mm high. “Its compact dimensions mean that customers can install secondary optics in line with their requirements”, said Osram.