Optotype projector with photoelectric measurement device

摘要

The invention relates to an optotype projector with photoelectric measurement device for use in subjective vision tests. It is the object of the invention to render the subjective vision test independent of errors due to contrast-reducing brightness in the room. It is the object of the invention to measure the contrast-reducing proportion of brightness in the room objectively and to emit a warning signal if a predeterminable limit value is exceeded. The essence of the invention resides in the combination of the projector with a measurement device which images the projection field on a photoelectric receiver and a display which indicates that the contrast-reducing brightness in the room has exceeded a limit value.