Holography is a Nobel-prize-winning technique developed in the late 40s by Denis Gabor that allows the recording of a fully three-dimensional image of an object.
The principle of the technique is that the time of propagation of light in a specific environment depends on the refractive index as well as the distance traversed (the optical path). Therefore, when a light wave travels through a sample with a varying refractive index and/or thickness, its wavefront is distorted and this change is reflected in the spatial distribution of the phase. The TESCAN Q-PHASE microscope allows to quantitatively measure the phase distribution in the projected sample plane, which in turn can be used for segmentation or cell boundary identification. This process of phase detection at a sample plane is usually referred to as Quantitative Phase Imaging and can provide information on sample morphology, topography or cell dry-mass distribution. Cell dry mass is quantified in pg/µm2 and can be calculated directly from phase values detected in each pixel. Quantitative phase imaging provides a very simple and sensitive way for monitoring of cell reactions to treatment and analyses of movement, growth, area, shape and many other parameters.
For more information click here.