Jaegers cha is used to measure

Jaeger's cha is used for measuring Near Vision The Jaeger cha is an eye cha used in testing near vision acuity. It is a card on which paragraphs of text are printed, with the text sizes increasing from 0.37mm to 2.5mm. This card is to be held by a patient at a fixed distance from the eye dependent on the J size being read. The smallest print that the patient can read determines their visual acuity