A new eikonometer: the multimeridional apparent frontoparallel plane

A new method for diagnosing and measuring aniseikonia is described. It is based on apparent frontoparallel plane (AFPP) settings when rod stimuli are presented in 45 and 135 degrees meridians as well as in the vertical meridian. The oblique presentation of the stimulus introduces a new approach to the study of aniseikonia. To explain the results obtained, new theoretical concepts have been presented. Clinically, the method is distinguished by its ease of application to nearly all patients with functional binocular vision.