Biological specimens exhibit poor amplitude (intensity) contrast, that poses a problem while visualizing living cells in - situ.

Other contrast mechanisms such as fluorescent markers are often toxic. Combined with confocal microscopy - related intense light has deleterious influence on viability of observed cells. Phase contrast imaging is designed to magnify slight modification in refractive indices of the constituent part of the cells into amplitude (intensity) fluctuations, which are registered by digital cameras. However, such phase contrast modalities as Differential Phase Contrast (DIC) or Nomarski phase contrast microscopy modify the optical path in the microscope, thereby excluding the possibility of observing the cell with the other modalities. Modification of objectives and illumination (from brightfield to phase contrast) requires time and imposes limitations on the rate of change detectable with phase contrast modalities. Also, the obtained images features side effects like halos that render automatic interpretation of the results and image manipulation (like cell counting) difficult.

BioPhase® is a unique device that allows 3D cell visualization without markers and phase contrast without side effects. Moreover, it does not modify the way a biologist observes the cellular material, and is complementary to such other conventional observation modes as TIRF, confocal and fluorescence microscopy.