Imaging biological cells using liquid crystals

Biological cells have been imaged using liquid crystals as an optical amplification medium. Preferential orientation of the liquid-crystal molecules at the surfaces of cells immobilized on substrates leads to well-resolved images, with very sharp contrast compared to images observed by standard phase-contrast microscopy. The feasibility of this technique has been demonstrated for muscle cells, fat cells, and neurons. Calculations based on a continuum elastic theory reproduce the observed features of the images of muscle and fat cells and allow us to estimate the optimum resolution that can be achieved by this technique.