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A hand optometer for measuring dark focus.

W Jaschinski-Kruza
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Abstract

To measure the accommodative state of the eye in a stimulus free condition, the so called dark focus, a simple optometer was constructed based on the principle of the polarized vernier optometer originally proposed by Moses (1971). Data obtained with this hand optometer were compared with those of two other subjective techniques, the polarized vernier optometer and the laser optometer, we were found to be similar. The advantage of this hand optometer is that it is a convenient device that allows one to measure the dark focus within minutes, under normal room lighting.

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Accommodation, OcularAdultDarknessHumansOptics and PhotonicsOptometryComparative StudyJournal Article

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W Jaschinski-Kruza. 1988. A hand optometer for measuring dark focus.. https://doi.org/10.1016/0042-6989(88)90043-0

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