1. Apparatus for in vivo detection of cataractogenesis in ocular tissue, comprising: a light source producing a substantially monochromatic, coherent, collimated light; optics coupled to said light source, and directing the light to impinge on the ocular tissue; a light collector positioned to collect light that is scattered from the ocular tissue, the scattered light having a fluctuating intensity; analysis electrical circuitry coupled to said collector for performing a mathematical analysis on the intensity and the fluctuations of the intensity of the collected light, thereby determining a signature of cataractogenesis, the signature including an intensity (I.sub.imm) of the light scattered by immobile scatterers in the ocular tissue; and processing electrical circuitry coupled to said analysis circuitry, and determining from the signature a degree of cataractogenesis.