Patent ID: 8149416

Claim:
An apparatus for detecting optical deformation in a sample contained on a sample holder, said sample containing at least one object, comprising: a light source which emits a first light beam which illuminates at least one stationary object on the sample holder; an optical forcing mechanism which provides an optically generated force on the at least one object to perturb the at least one object, said optical forcing mechanism including: a laser which emits a second light beam onto the at least one object; and a spatial light modulator which diffracts said second light beam and which applies the optically generated force to the object and generates a superposition of an unmodified image of the object and a phase-shifted or diffracted version of said image of the at least one object; and a detector which detects an interference pattern between a first portion of said first light beam which is undiffracted, and a second portion of said first light beam which is diffracted by the at least one object in the sample, wherein in said superposition of said unmodified image and said phase-shifted or diffracted image, said detector determines an optical path length change as a result of said optically generated force on the at least one object, said optical path length change yielding an optical deformation of the at least one object.