SFH 7776 Digital Sensors
Apr 2013OSRAM Opto Semiconductors Inc.Request Info
SUNNYVALE, Calif., April 29, 2013 — Osram Opto Semiconductors’ new compact SFH 7776 digital sensor registers the ambient brightness in smartphones and prevents unintentional responses from the touch screen during calls, enabling smartphone designers to control the backlighting and touch functions of displays.
The sensor uses an IR LED and two detectors to register the ambient brightness to control the display backlighting so that it can be easily read while consuming as little power as possible. It emits IR light that is reflected by approaching objects — such as your ear — to deactivate the touch function on the display when the phone is held up during a call.
The sensor has a working range of up to 16 cm and is only 1.35 mm high since it requires no lenses to collect the emitted infrared light. The sensor features a power consumption of just 0.8 µA in standby mode.
Its detection limit of 0.002 lx allows for usage behind dark casing panels. Designers can place the sensor anywhere and do not need a special translucent window. The ambient light sensor does not react to short-term fluctuations in the brightness of various lamp types caused, for example, by changes in the power supply frequency, ensuring that the display backlighting remains constant.
The sensor eliminates crosstalk in the component itself, removing the need for separate optical barriers between the IR LED and the detector. Since the sensor covers the complete working range from 0 to 16 mm, it reacts to direct contact, therefore deactivating the touch function of the display.