Eye tracking

Eye tracking is the technique of recording eye movements. One of the first successful visualization attempts used a kymograph and a lever construction connected to a contact lens made of plaster-of-Paris. Obviously, this is not the most pleasant recording technique since it affects the eye and its movements through the lever. The American psychologist Raymond Dodge introduced the first contact-free eye tracker which was able to record horizontal eye movements on a photosensitive plate. Since then eye movement research gained a lot of momentum with new methods, which have made eye tracking an inexpensive and easy-to-use technique. Current methods include "videotaping" the eye (videooculography), magnetic coils (search coils), infrared reflections (limbustracking, dual-purkinje imaging) and skin electrodes (electrooculography).

The interested reader is referred to the review "Eye Movement Recordings: Methods" by T. Eggert.