Speedy scanner

Engineers at UCLA have designed a bar code reader that is nearly a thousand times faster than any device currently in use.

The traditional bar code is read by optically scanning the code's alternating light and dark bars and then using a computer program to convert the resulting image into digital form, essentially 'decoding' the information stored within the code.

Conventional bar code readers use one of two approaches to acquire an image of the bar code. In one, a laser beam is scanned over the code to measure the intensity of the light reflected back by the black-and-white pattern. In such devices, the activity of the mechanical scanner limits the image-acquisition speed to less than 1,000 frames per second. In the second type, a digital camera, such as a CCD- or CMOS-based device, takes a picture of the code, which is then recognised by the computer. The frame rate of these devices is limited to about 1,000 frames per second by the refresh rate of the CCD or CMOS image sensor.