OSRAM Opto Semiconductors, Santa Clara, CA, offers the SFH7740 and SFH7741 SMT proximity sensors that use distance measurements to detect a mobile device's operating status without physical contact to the sensor itself. The SFH7740 has an optical touch switch and measures 3.7 by 3.7 by 1.0 mm and reacts to distances from 0.5–4.0 mm. Depending on whether the slider phone's slider is open or closed, the sensor switches the display lighting off or on. The SFH7741 reacts at a 20 mm typical working distance and is suitable for a range of applications. Both devices draw 50 µA approx. and use integrated ambient light suppression.
OSRAM Opto Semiconductors