Osram develops ‘glow-free’ IR LED for facial recognition

21 Feb 2018

With its wavelength of 940 nm, the Synios P2720 reduces distracting problem of red glow.

It's you: 940 nm light sources can now be used, improving facial recognition.

Smartphones, tablets and diverse devices needing controlled and secure access can now be unlocked in different ways: with a password, fingerprint scan or even an iris scan. Now 2D facial recognition is another method, which involves illuminating the user’s face with an infrared light source and capturing the image with an IR camera.

The system then compares the image with the images previously stored for the purposes of identification, focusing on characteristic two-dimensional features. 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.

By using a wavelength of 940 nm, Osram Optical Systems’ Synios P2720 infrared emitting diode (“IRED”) reduces the red glow that can occur with infrared light sources in the short-wave infrared range. Previously, the company says, the sensitivity of IR cameras was only good if the light source had a wavelength of 850 nm.

These cameras have been further developed to give them greater sensitivity in longer wavelength ranges so 940 nm light sources can now be used – which in turn improves the overall performance of the facial recognition system.

Even light

Osram adds that “bright and uniform illumination of the user’s face or eyes is particularly important for facial recognition and also for eye-tracking systems”. The P2720 delivers an output of 1,150 mW at 1 A. With this high overall output it has a radiant intensity of 360 mW/sr.

The Synios P2720 IR LED has the same footprint as the 850 nm version.

The P2720 has the same footprint as the 850 nm version. Measuring only 2.0 x 2.75 x 0.6 mm, the IRED is therefore ideal for space-critical applications.

Furthermore, the IRED has no optics. Its compact dimensions mean that customers can install secondary optics in line with their requirements.

Nina Reiser, Marketing Manager for the Emitter Laser Sensor segment at Osram Opto Semiconductors, commented, “Everyone wants the reassurance that the data on their mobile devices is as secure as possible.

"Our extremely powerful and bright IRED illuminates the facial characteristics of users perfectly, ensuring that only authorized persons have access to the device.”

This IRED for 2D facial recognition is the latest addition to Osram Opto Semiconductors’ existing portfolio for biometrics. The new Synios P2720 is now available for initial customer projects.