CALIBRATION OF THE INFRARED OPTOMETER
Abstract
An infrared optometer for measuring the absolute status of accommodation is subject to a constant error not associated with chromatic aberration or changes in fixation. The reflections of infrared light within the eye cannot be considered to originate from the retina or pigment epithelium alone. Probably the choroid and sclera are involved giving a diffuse reflection and increased intraocular stray light. A schematic eye, using a retina of 2-mm. opalescent plexiglas with a sanded surface, approximately simulates the behavior of the human eye. Changes in fixation have only a slight effect on optometer accuracy as long as the pupil does not vignette the optometer beam. A modification is described for calibrating the infrared optometer for an individual subject without using trial lenses or a subjective optometer. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1962
- Accession Number
- AD0288884
Entities
People
- Merrill J. Allen
Organizations
- Indiana University Bloomington