Optical Proximity Sensor Makes It Automatic For Consumer Appliances

Compact mobile devices have a new miniature, low-cost optical proximity sensor at the ready. In mobile phones, for example, the HSDL-9100-021 sensor makes it possible to automatically change from the loudspeaker to the earpiece mode when the phone is placed near the ear. Current phone models require user intervention to switch between both modes. The sensor also can detect the opening and closing of popular clamshell mobile phones and activate the power-saving mode in notebook computers.

Developed by Agilent Technologies, the sensor is well suited for paper-edge detection in printers, photocopiers, and fax machines. It also can be used to switch home appliances such as table lamps on and off without the need for mechanical switches. Many other potential applications exist within the consumer, industrial, and automotive markets.

The sensor is specifically optimized for size, performance, and ease of design in mobile appliances. Its small footprint (7.1 by 2.75 mm and only 2.7 mm high) suits space-constrained applications. It offers a variable detection range from zero to 60 mm (2.4 in.) that lets manufacturers easily customize the device for multiple applications. The sensor's metal housing shields the LED emitter from the photodetector. The surface-mount, lead-free package eliminates optical crosstalk between the emitter and the light sensor to ensure a high signal-to-noise ratio. The unit also features an integral ambient light filter and guaranteed performance from ­25°C to 85°C.

Available now, the HSDL-9100 costs $0.91 each in 50,000-unit quantities.