A visual acuity device measures the visual acuity of a patient's eye by directing a pulsating beam of light on the eye and detecting the resulting reflection. A primary pattern having a pattern formed by transparent and non-transparent portions is positioned in the optical path of the pulsating beam of light. A fixed pair of analyzer or secondary pattern is positioned in the optical path of the beam of light reflected from the patient'eye. One of these analyzer or secondary patterns has a pattern which substantially corresponds to the pattern of the primary fixation pattern and the other has a pattern which is the negative mirror image of the pattern of the first analyzer or secondary pattern. The beam of light reflected from the patient's eye is divided by a beam splitter so that each of the analyzer patterns receives the reflected image of the primary pattern from the patient's eye. A photoelectric device is associated with each of the analyzer patterns for detecting the reflected beam of light passing through each of these analyzer patterns to generate an electrical output signal. The photoelectric devices are connected to a difference amplifier for eliminating any glare and generating a signal which is determinative of the visual acuity of the patient's eye. Far visual acuity can be measured by using infrared light adding a collimating and compensating lens. Thus, the visual acuity device objectively measures both far and near visual acuity.
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