Abstract: A system for imaging an object in or behind a highly scattering medium includes a light source for illuminating the highly scattering medium with a beam of light. The light emerging form the highly scattering medium consists of a ballistic component, snake-like component and a diffuse component. A 4F Fourier imaging system including a Fourier spatial filter located at 2F is used to form a time gated image of the emerging light, the time gated image consisting primarily of the ballistic component and the snake-like component.

Abstract: A method and system for compressing and amplifying light pulses using degenerate cross-phase modulation and degenerate four-wave mixing. A probe pulse and a pair of pump pulses are arranged so as to copropogate in condensed matter with the pump pulses having the same frequency as the probe pulse. The first pump pulse overlaps with the front end of the probe pulse while, the second pump pulse overlaps with the tail end of the probe pulse. The probe pulse is linearly polarized. The pump pulses are orthogonally polarized relative to the probe pulse so that they can be filtered out using a polarizer and have a greater intensity than the probe pulse. The propagation constant mismatch between the probe pulse and the pump pulses is equal to about zero.

Abstract: An oscilloscope constructed for use in real time resolving an ultrafast voltage signal includes a streak camera having a transmission line photocarthode, a constant light source for illuminating the photocathode, an input coupled to the transmission line photocathode, an accellerating mesh, a pair of sweep electrodes, electron multiplication means, a phosphor screen and a DC high voltage source. In use, the voltage signal to be examined is applied to the input. When the voltage signal on propagating through the photocathode intersects in time and space on the photocathode with the light from the light source, a number of electrons proportional to the intensity of the voltage signal are emitted from the photocathode. These electrons are then accelerated, deflected by the pair of sweep electrodes, multiplied by the microchannel plate and then impinge upon the phosphor screen, creating an optical image having an intensity proportional to the number of impinging electrons.