摘要 |
An optical system, such as a bar code scanner, illuminates an image with a multi-wavelength device. Under a first embodiment, a tunable laser is optically coupled with a prism or other wavelength separation device. As the laser beam wavelength varies, the transmission path through the prism changes, resulting in a scanning of the beam across an image. A photodetector captures light reflected from the image and sends it to a microprocessor for decoding. Under another embodiment, a broad band light source transmits light through a prism, thus shining a "rainbow" on the image. A spectrometer measures reflected light as a function of wavelength and sends the resultant signal to a microprocessor for decoding. Neither embodiment relies on moving parts to scan the image.
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