Osram SFH 4170S and SFH 4180S infrared LEDs for biometric identification

As consumers store more and more sensitive data on their smartphones and smart watches, various methods of biometric identification are being used to provide security and form a ‘lock’ against unwanted access. Osram’s infrared LEDs (IREDs) SFH 4170S and SFH 4180S are designed to help meet this demand.

The compact dimensions of the specially developed Oslon P1616 package (1.6 x 1.6 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 are said to require about 50% less space.

Despite the small dimensions, the IREDs uphold power of 1150 mW at 1 A and a radiation intensity of 280 mW/sr. These characteristics are particularly important for 2D face recognition, which focuses on features of the user’s face such as 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 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 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 unpopular in consumer applications.