A precise and inexpensive magnetic field search coil system for measuring eye and head movements in small laboratory animals.

The design of a magnetic field search coil system based on the phase detection principle is described. The system was developed to record eye and head movements of small, unrestrained laboratory animals. It is compact, linear over 360 degrees, has a high resolution and allows the use of minute, commercially available search coils. Potential pitfalls and critical factors in the use of the system are discussed and original movement records are presented.