SANTA CLARA, Calif., April 24, 2008 -- Osram Opto Semiconductors said its two new SMT (surface-mount technology) proximity sensors (SFH7740 and SFH7741) use distance measurements to detect a mobile device’s operating status without physical contact to the sensor itself. This technology allows for the automatic shut off of displays and keypads when no longer needed, improving performance and efficiency of products such as cell phones and digital cameras. The proximity sensors can also be used to adjust the volume of the device’s speakers.

The SFH7740 proximity sensor with optical touch switch measures 3.7 x 3.7 x 1.0 mm and reacts to distances between 0.5 and 4.0 mm. These compact dimensions allow it to be unobtrusively integrated into unusual designs, such as extremely low-profile devices. For example, it is small enough to fit in slider phones where it can detect the position of the slider that reveals or hides the keypad. Depending on whether the slider is closed or open, the SFH7740 switches the display lighting off or on.

Osram Opto said the sensor is an ideal alternative to Hall sensors as it is insensitive to electromagnetic interference and does not produce any electromagnetic interference itself.

Osram's other new proximity sensor -- model SFH7741 -- reacts at a typical working distance of 20 mm and is suitable for a wide range of applications, the company said. For example, it can detect when the phone is moved close to the ear, taking the display and the keypad out of the user's sight. The backlighting is then switched off and the volume adjusted. In hands-free mode with the phone well away from the ear, the backlighting can be switched on and the volume adjusted accordingly.

The sensor can also help save energy in digital cameras, switching off the display lighting whenever users holds the camera up to their eyes and use the viewfinder instead of the screen, Osram said.

The two SMT sensors draw a current of 50 µA (approx.), making use of integrated ambient light suppression to operate reliably in all lighting conditions, the company said.

For more information, visit: www.osram-os.com; e-mail: info@osram-os.com

Osram Opto Semiconductors Inc.
2650 San Tomas Expressway
Suite 200
Santa Clara, CA 95051
Phone: (888) 446-7726

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