Early 20th century ophthalmoscopy tool. Ophthalmoscopic tools are used to examine the interior of the eye and measure its optical properties. This is

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Early 20th century ophthalmoscopy tool. Ophthalmoscopic tools are used to examine the interior of the eye and measure its optical properties. This is a DeZeng refractometer dating from the first decade of the 20th century, and invented by the prolific US instrument maker Henry DeZeng. This instrument is used to measure refraction within the eye.

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Size: 6144px × 4096px
Photo credit: © MARK THOMAS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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