RESUMEN
An accurate and relatively simple method of measuring eye and contact lens movement has been developed. A hidden ultra-high-speed motion picture camera, a digital film data analyzer, and computer data reduction are used to define and separate eye, head, and contact lens movements. The technique has an eye rotational accuracy of about 0.2 degrees and a linear translational accuracy of better than 0.05 mm over a field of view of more than 60 degrees. This procedure requires no extraneous hardware, fixtures, or eye restraints, so data can be obtained in a natural environment. It provides a method of evaluating motility training procedures, studying contact lens fitting methods, and investigating tear pumping mechanisms.
Asunto(s)
Lentes de Contacto , Movimientos Oculares , Optometría/instrumentación , Computadores , Humanos , Películas Cinematográficas/instrumentación , Optometría/métodos , Movimientos SacádicosRESUMEN
Accommodation causes variation in both visually evoked response (VER) amplitude and implicit time. Measurements indicate an average decrease in amplitude of about 1 muV per diopter and an increase in implicit time of about 1.5 msec per diopter for increasing amounts of accommodation. Care should be taken to eliminate any accommodative stimulus which could alter the normal VER response during clinical evaluation.
Asunto(s)
Acomodación Ocular , Potenciales Evocados Visuales , Adulto , Humanos , Persona de Mediana Edad , Estimulación Luminosa/instrumentación , Estimulación Luminosa/métodosRESUMEN
A simple water cell can be used to increase the range of an ordinary lensometer by about three times by using an application of Snell's law. This technique can be very useful in low vision applications where other methods of measuring high plus ophthalmic lenses are always cumbersome and time consuming and sometimes inaccurate or inconclusive.