Retinoscope wheel of von Hess
Retinoscope wheel of von Hess was one of the earliest instruments to contain the lenses needed to determine the refractive state of the eye.
The retinoscopic wheel of von Hess predated the phoropter. It was used for retinoscopy before the phoropter was invented.
Carl von Hess was born in 1863 and died in 1923.
