Infrared-LEDs from Osram enable face recognition in smartwatches

The two smallest biometric identification products to date

Source: Osram

The more we rely on our digital companions, the more important the security of sensitive data on our smartphone or smartwatch becomes. Various methods of biometric identification provide the user with security and form a reliable "lock" against unwanted access.

For manufacturers of mobile devices, the size of the individual components plays a central role in the design of their products. Osram's new infrared-LEDs (IREDs) SFH 4170S and SFH 4180S meet this demand by being the smallest biometric products by the Munich-based high-tech company.

Smartwatches are becoming more and more popular and can do more and more. In contrast to smartphones, where the screen can't seem to be big enough, smartwatches focus on being smaller in size. The particularly compact dimensions of the specially developed Oslon P1616 package (1.6 mm x 1.6 mm x 0.85 mm) make the SFH 4170S and SFH 4180S the smallest Osram components for biometric applications. Compared to similar products today, the two IREDs require about 50 percent less space.

Despite the small dimensions, the IREDs uphold an outstanding power of 1150 mW at 1 A and a radiation intensity of 280 mW/sr. These characteristics are particularly important for 2D face recognition. This identification method focuses on two-dimensional features of the user's face, for example, the length of the bridge of the nose, the distance between the eyes or the distance from corner to corner of the mouth. In order to reliably compare the image stored in the system with the current picture, the infrared camera must be able to capture the best possible images – making homogeneous illumination of the face with an infrared light source a central aspect of this application.

Depending on where the IREDs are ultimately used, customers can choose between the 850 nm (SFH 4170S) or the 940 nm (SFH 4180S) version. While the SFH 4170S benefits from the very high sensitivity of the sensors in this wavelength range, the SFH 4180S avoids the "red glow" effect, which can be seen by the human eye and is particularly unpopular in consumer applications.