Holographic Microscopy

Holographic microscopy is the most common form of quantitative phase imaging. The HoloMonitor^® live cell imaging microscope employs digital holographic microscopy to allow non-invasive visualization and quantification of living cells without compromising cell integrity.

Conventional Holography

A traditional hologram is recorded on a photographic plate. The holographic image is created by illuminating the developed hologram with the laser that was used to create the hologram. This recreates the same light wavefield that originally came from the imaged object. The object appears to be 3-dimensional as each eye image a slightly different part of the wavefield, just like they would have done if the object was still there.

Digital Holography

The advent of high-resolution image sensors has made it possible to instead record a hologram digitally, allowing the holographic image to be created by a computer, rather than re-illuminating the developed hologram. The computer actually creates two images: an amplitude (intensity) and a phase image. As unstained cells are transparent, most of the information resides in the phase image.

The Holographic Microscopy Principle

Holographic microscopy creates (quantitative) phase images by letting a sample beam and a reference beam interfere to create an interference pattern or hologram, as shown in the principle image below. The hologram is recorded by an image sensor and computer-processed to produce the final phase image.