High-Speed Optical Image Compression at Lower Power

In an alternative to the optical image-compression method of the preceding article, the Fourier transform of the input image would be formed on the output plane by white-light holography, instead of by laser holography. The principal advantage of the alternative method would be decreased power consumption: A state-of-the-art liquid-crystal spatial light modulator needed to implement the method of the preceding article consumes about 10 W of operating power, and the liquid crystals must be maintained at a temperature near 25 °C. On the other hand, an image detector of the active-pixel-sensor (APS) type, needed to acquire the Fourier-transform image in both the method of the preceding article and in the alternative method, consumes only about 50 mW. Because the spatial light modulator would not be needed in the alternative method, the power consumption of the image-compression system could be greatly reduced.