Patent ID: 10768339

Abstract:
The present disclosure describes an imaging system, method, and apparatus for identifying a latent image of a hidden object. A light source generates a first beam of narrow-band light and a second beam of narrow-band light that has temporal fluctuations correlated with the first beam. A frequency modulator shifts a temporal frequency of at least one of the first beam or the second beam. The first beam is directed towards a first scattering surface and the second beam is directed towards a second scattering surface. The first scattering surface scatters the first beam to a scattered light that illuminates a hidden object. The hidden object reflects at least a portion of the scattered light towards the second scattering surface, the reflected light interferes with the second beam and produces an interference pattern on the second scattering surface. A lock-in camera detects an irradiance of the interference pattern, monitors temporal variations of the irradiance caused by the temporal frequency shift introduced by the frequency modulator, and identifies a complex-valued light field that represents information of the hidden object based on the temporal variations of the irradiance.