BACKGROUND OF THE INVENTION

Lateral shearing interference microscopes (also referred to as Digital Holographic Microscope, DHM, or Quantitative Phase Imaging, QPI) are used to measure the phase in transmission of light through objects in a sample plane of the microscope. In particular, lateral shearing interference microscopes have been used for 3D cell measurements in biological samples, with the phase measurement allowing the optical thickness of the cell to be measured. In some cases, for example, in the case of densely populated biological samples or samples with a high concentrations of cells, existing techniques for taking sheared microscopic measurements suffer from data loss due to overlapping sheared images. One problem in using a standard biological microscope slide to make shearing interferometry measurements of samples having more concentrated cell populations is sample overlap in the resulting sheared microscopic measurements (e.g., laterally sheared interferograms). The sample overlap due to lateral shearing can generate unwanted artifacts in the measurement making it difficult to interpret and to obtain accurate information regarding the sample being measured. Accordingly, a technique is disclosed to enable shearing interferometry measurements to be taken while avoiding problematic sample overlap.

