Safety in focus: infrared LED for iris scanners protects against intruders

Osram Opto Semiconductors is set to present a new infrared LED (IRED) for iris scanners at the upcoming Mobile World Congress. The SFH 4787S illuminates the eyes so evenly that the software identifying the iris pattern now hardly needs to correct artefacts. Like its predecessor, its direction of emission is slightly angled rather than vertical, thus simplifying the design process by eliminating the usual mechanical aids.

Iris recognition is among the most reliable biometric identification methods. In brief, iris scanners illuminate the eyes with infrared light and a camera takes a photograph. Special software then uses this to detect the iris pattern, which is unique to each individual.

Osram Opto Semiconductors is a technology leader in this field. Two years ago, the company was first to market an infrared LED that brought this technology to smartphones and other mobile devices. This was followed by a version with a slightly angled direction of emission, which meant that designers no longer need mechanical aids to tilt the entire LED. The angle of emission aligns with the camera’s field of view.

Even illumination simplifies processing

This third-generation Osram IRED for iris recognition meets another need in this application: the brightness differences in the camera images should ideally only originate from the iris pattern and not be additionally caused by a gradient in the illumination. This would mean that the software needs to correct fewer artefacts when determining the iris pattern. With the SFH 4787S, Osram has thus developed an emitter with a flat light, optimizing the reflector and lens to ensure virtually constant intensity across the emitted light beam.

Apart from this, the SFH 4787S is almost identical to its predecessor, the SFH 4786S. Both are based on the compact 3.5 x 3.5 x 1.6 millimeter large Oslux package. A wavelength of 810 nanometers (nm) delivers high-contrast images for all eye colors. The emission direction is tilted by 8°, while the emission angle is ±18°. The optical output of this highly efficient emitter is 720 milliwatts (mW) at a current of 1 amp, with a radiant intensity of 1,000 milliwatts per steradian (mW/sr).

Industrial applications gaining ground

The impetus to develop more compact and reliable iris scanners was driven by the need for dependable solutions to safeguard mobile devices from unauthorized access. Gradually, the technology is now making its way into other sectors. “Access control as a whole is becoming increasingly important and iris recognition remains one of the most reliable methods here,” explains Bianka Schnabel, Marketing Manager at Osram Opto Semiconductors. “Following in the footsteps of consumer markets, we are now also seeing an upswing in interest from various industries.”

ABOUT OSRAM

OSRAM, based in Munich, is a globally leading lighting manufacturer with a history dating back about 100 years. The product portfolio includes high-tech applications based on semiconductor technology such as infrared or laser lighting. The products are used in highly diverse applications ranging from virtual reality, autonomous driving or mobile phones to smart and connected lighting solutions in buildings and cities. In automotive lighting, the company is the global market and technology leader. Based on continuing operations (excluding Ledvance), OSRAM had around 24,600 employees worldwide at the end of fiscal 2016 (September 30) and generated revenue of almost €3.8 billion in that fiscal year. The company is listed on the stock exchanges in Frankfurt and Munich (ISIN: DE000LED4000; WKN: LED 400; trading symbol: OSR). Additional information can be found at www.osram.com.