He was a professor at the University of Vienna, and was son to oculist Friedrich Jäger von Jaxtthal (1784-1871), and grandson to Georg Joseph Beer (1763-1821).
Jäger is remembered for his work involving eye operations, and for his research of ophthalmic disorders.
He was an early practitioner of the ophthalmoscope, and was among the first to use ophthalmoscopy to determine refractive error in the eye.
[1] In the 1850s Jäger made improvements to eye chart test types that were earlier developed by Heinrich Küchler (1811-1873).
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