March 6, 2017 -
Osram Opto Semiconductors introduced a new infrared LED (IRED) for iris scanners at last week’s Mobile World Congress that, according to the company, illuminates the eyes so evenly that the software identifying the iris pattern hardly needs to correct artifacts.
The direction of emission of the new SFH 4787S is slightly angled rather than vertical, simplifying the design process by eliminating the usual mechanical aids.
Osram Opto Semiconductors introduced its first generation of this technology for smartphones and mobile devices a couple of years ago, followed by a version with a slightly angled direction of emission, which meant that designers no longer needed mechanical aids to tilt the entire LED.
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 artifacts when determining the iris pattern.
With the SFH 4787S, Osram has developed an emitter with a flat light, optimising 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 3.5 x 3.5 x 1.6mm Oslux package. A wavelength of 810 nm delivers high-contrast images for all eye colours. The emission direction is tilted by 8degress, while the emission angle is ±18 degrees. The optical output of the emitter is 720 mW at a current of 1A, with a radiant intensity of 1,000 mW/sr.