Holography and Holographic Interferometry
Holography can be seen as a novelty used to create 3D photographs for interesting museum displays, but its principles work at the root of physics, providing us with invaluable information. ... I will look at how holographs are created before looking at how the technology was refined to be used in holographic interferometry and its applications and effectiveness. Holography literally means “whole message”. ... He had discovered holography when attempting to improve electron microscopes by using light beams. The principle of holography is to record not the colour and intensity of light falling on a film, as in a photograph, but an accurate recording of the characteristics of the light that came from the object so that a “whole message” is recorded. ... In 1960 the LASER was produced, allowing the method of holography to be developed and become a valuable study of light. ... This allowed bigger, opaque objects to be used, and holography became more useful with wider applications. ... The work of Gabor and fine tuning of Leith and Upatnieks formed a solid basis of holography, but it’s the further explorations of its applications that have been more rewarding. From the entertainment field, where holographic cinematography is researched, through to the medical field, including research into three dimensional dental records, holography has been put to good use; however the best practical use of this technology is holographic interferometry. ... Research started looking into this, using the principles of optical interferometry combined with the new holographic technology. ... Optical interferometry was superseded by this technology. However useful for certain studies, classical interferometry is limited. ... With holographic interferometry, the waves can interact at different times and different positions, using any object, smooth or not, allowing for numerous sets of experiments and extended studies.