The present invention utilizes a holographic optical forcing array for dynamic cellular probing and diagnostics. A holographic optical trapping system generates optical forces on objects so that deformations thereof may be quantified. In one embodiment, digital holography is used to generate an interference pattern, and an analysis thereof determines the phase profile which yields a measurement of the objects' shape deformation using only one image. In another embodiment, phase-stepped holography allows the phase profile of an object to be measured using only one image, by using a holographic optical element to make phase-shifted replicas of the beam in space. In another embodiment, the optical forcing array applies optical forces to beads placed on the objects' surface, deforming the objects. The beads' position is determined by applying Mie theory, and analysis thereof yields the three dimensional position of the beads, and a measurement of the deformation displacement on the objects' surface.