How it works: Technology underlying optical coherence tomography

^{Figure 1: Basic Michelson interferometer around 1880}

In terms of advancing patient diagnosis and treatment in ophthalmology, light is a gift that keeps on giving. Traditionally the human vision system was the key mode of observation of the anterior and posterior eye and, for a time, the fundus camera was the ‘gold standard’ image capture system of retinal structures.

While the diagnostic information provided by the fundus camera system was of high value, each pixel in the image could be considered as the sum of photons scattered from adjacent tissues sites and so resolution could be degraded. Also, details of deeper structures could not be readily detected.