Acousto-optical imagery system based on coherent holographic detection in real time

An acousto-optical imagery system based on coherent holographic detection comprising an optical source of pulsation .omega..sub.o, an electro-optical and photoconductive holographic recording crystal, a device forming a convergent cylindrical optical wave of pulsation .omega..sub.o from the wave emitted by the source, an ultrasonic cell containing a refractive fluid in which an object to be analysed is placed, an ultrasonic wave emitter emitting an ultrasonic wave of pulsation .omega..sub.s, said ultrasonic wave passing through the object to be analysed, said ultrasonic wave and said cylindrical optical wave interacting in the cell to form, by BRAGG diffraction of the optical wave, diffracted orders containing the optical images of said object to be analysed, an additional optical device intended to supply a plane optical reference wave of pulsation .omega..sub.o +k.omega..sub.s, k being equal to +1 or -1, according to whether the diffracted order to be imaged is the order +1 or -1, said diffracted order and said plane optical reference wave being directed towards said crystal to form interference fringes in said crystal;

• said electro-optical and photoconductive holographic recording crystal having electrodes connected to a voltage source, a unit for reconstructing from the interference fringes stored in said crystal an image of said object in real time;
• said unit comprising means for supplying from said source a plane optical reading wave having the same pulsation and direction as the reference wave, but being propagated in the opposite direction thereto, and an optical device forming said image of the object in a viewing plane from the read out beam reconstructed from said crystal, the object thus being viewed in real time.