A tiny opto-mechanical sensor which recognises if it is tilted vertically or horizontally could help digital cameras ‘know’ if a picture is being taken in portrait or landscape format.
When equipped with the appropriate software, the camera would immediately store the images with the correct orientation so that the user would not need to tilt the camera to view the pictures. In addition, users would no longer have to spend time rotating images on the monitor after the pictures have been transferred to the computer.
The new orientation sensor was developed by the Siemens subsidiary Osram Opto Semiconductors, which recently presented it at the Electronica trade fair in Munich. The sensor is especially designed for use in mobile devices such as cell phones, MP3 players and digital cameras.
Known as SFH 7710, the new sensor is a small, energy-efficient component with a digital output. The sensor measures 4mm2 and is 1.8mm high. It operates on a supply voltage of 2.5V and requires 50µA of electricity on average so as not to put too great a strain on the battery of a camera or cell phone.
The sensor uses a tiny metal pellet and a light barrier. Measuring less than 1mm in diameter, the pellet can move freely along a predefined path, where its position is influenced solely by the force of gravity. The light barrier is blocked if the pellet is located at one end of the path, while moving it to the other end enables signals to get through to the light barrier’s receiver.
This digital signal is processed by the camera’s software, which rotates the image to the correct position when saving it to the memory. As a result, pictures automatically appear in the correct format on the camera’s display. The sensor is designed to fit into very small devices and it can determine if it is tilted to the right or left. Two sensors are required to cover both of these directions, and three suffice to determine exactly how the device is oriented in three dimensions.