Illumination field for gesture recognition provided by high-power infra-red LED

April 13, 2013 // By Christoph Hammerschmidt
With an optical output of 1030 mW, the infrared (IRED) Oslon black SFH 4716S from Osram Opto Semiconductors is one of the most powerful IREDs on the market, its makers assert. With a beam angle of 150 degrees this IRED offers illumination at a range of a few metres. The vendor positions the new IRED for gesture detection systems linked to computer games or for optical safety systems in the automotive sector.

This high-power IRED illuminates the area relevant for gesture recognition so that a camera sensor can detect movement which will then be used to control a computer or enter text. The wide beam angle of 150° ensures that the near-field area is uniformly illuminated and gestures are reliably detected. Text can therefore be entered, for example, even if the hand is a few centimeters away from the keyboard. The SFH 4716S is also certified in accordance with the Automotive Standard so it can be used in safety-related applications such as driver monitoring or seat occupancy detection systems in vehicles.

A possible application for SFH 4716S is gesture detection: text entry or image processing without touching the keyboard.


Its high optical output of 1030 mW is achieved at an operating current of 1A with an efficiency of around 35%. This increased performance is based on stack technology with which Osram provides each chip with two emission centers, thereby doubling its output. Oslon black achieves a radiant intensity of up to 225 mW/sr. (Radiant intensity is measured in milliwatts per steradian - the unit of solid angle - indicating the light output within a solid angle segment and therefore defines the intensity of the light beam. The emitted light with a wavelength of 850 nm is suitable for camera sensors but is barely visible to the human eye and therefore is not considered annoying.

The high optical output of the Oslon black also makes it suitable for combining with external reflectors. It may initially seem contradictory to create a narrow beam from a wide-angle light source but in actual fact this is a very efficient way to achieve high radiant intensity and long ranges, Osram says. The light from the SFH 4716S injects well into an external reflector. The reflector shapes the beam so that it can be tightly focused by an additional lens. This makes it suitable for surveillance systems