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We describe, demonstrate, and characterize an analog self-electro-optic-effect device that gives a difference between two optical output powers that is linearly proportional to an electrical or an optical drive. Such a device should permit bipolar (positive and negative) processing in novel image processing arrays. The device is able to operate over a range of more than 4 orders of magnitude of optical power from 50 nW to 2.5 mW, corresponding to uniform incident intensities as low as 3.3 mW/cm(2). The frequency response (3-dB limit) varies linearly from 7 kHz at 1-µW absorber power to 3.5 MHz at 1 mW of absorbed powers.

Experimental results of light pulse transmission through thick turbid media are presented. Measurements have been carried out on polystyrene latex spheres by using a picosecond thin laser beam and a streak camera system. The results show that the shape of the received pulse depends mostly on the transport mean free path and on the absorption coefficient of the medium, indicating that both the absorption coefficient and the asymmetry factor of the scattering function can be obtained from the pulse shape. The results also show that a detectable amount of received photons follows trajectories near the source receiver line even for large values of optical depth, indicating the potential of a time-gated scanning imaging system to detect absorbing structures inside thick turbid media.