A Scheiner-Principle Pocket Optometer for Self-Evaluation and Biofeedback Accommodation Training.
Abstract
Most humans tend toward myopia when presented with a visual field without sufficient detail to stimulate focusing mechanisms. This means that a pilot flying in darkness, or in an 'empty field' such as empty sky, will be likely to focus nearer the windscreen than at the optical infinity required to focus on visual targets of probable interest. Biofeedback training to counter ths problem has been limited in practical application by expensive and cumbersome instrumentation. A Scheiner-principle optometer has been developed for self-evaluation of accommodative state and biofeedback training. The specific advantages of the new invention over earlier optometers are: (a) simplicity of design; (b) hand held, portable implementation; (c) light weight; (d) small size; (e) low manufacturing cost; (f) the use of a monochromatic light source to eliminate the effects of chromatic aberrations in the subject's eye; and (g) effectiveness as a training aid. Four prototypes of the pocket optometer have built and were used to implement biofeedback training to correct night myopia in 12 Navy aviation candidates. All subjects were emmotropic in full light. Training was limited in duration due to the transient nature of subject availability but was reasonably successful in 10 out of the 12 cases.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 19, 1989
- Accession Number
- ADA213171
Entities
People
- William B. Cushman
Organizations
- Naval Aerospace Medical Research Laboratory