Infrared LEDs are enabling biometrics on smartwatches. Source: OsramInfrared light-emitting diodes (ILEDs) from Osram are enabling biometric features on smartwatches.
The SFH 4170S and SFH 4180S ILEDs require about 50% less space than other biometric devices with 1,150 mW of power at 1 A and a radiation intensity of 280 mW/sr.
The identification method focuses on 2D features of a user’s face — such as the length of the bridge of the nose, the distance between eyes or between corners of the mouth — and compares the image stored in the system with the current picture. In order for the infrared camera to capture a reliable image, the infrared light source must be a central aspect of the smartwatch.
The SFH 4170S benefits from the high sensitivity of sensors in the 850 nm wavelength range while the SFH 4180S avoids the red glow effect that can be seen by the human eye.
As biometric identification is becoming more important, the challenge is to incorporate the technology into smaller form factors, Osram said. The two ILEDs allow new biometric applications to be ported to smaller portable gadgets such as smartwatches.
