Jaeger chart

The Jaeger chart is an eye chart used in testing near vision acuity. It is a card on which paragraphs of text are printed, with the text sizes increasing from 0.37 mm to 2.5 mm.[1] 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.[2] The original 1867 chart had a text containing seven paragraphs and a corresponding seven-point scale.[3]

Jaeger cards are not standardized, and the variability of the actual size of test letters on different Jaeger cards currently in use is very high.[4] Therefore, test results with different Jaeger cards are not comparable.

More commonly, distance vision acuity is tested using the Snellen chart, familiarly seen wall mounted with a large letter at the top.

References
  1. Blesi, Michelle; Wise, Barbara; Kelley-Arney, Cathy (2011). Medical Assisting Administrative and Clinical Competencies. Cengage Learning. pp. 888–890.
  2. G.K. & Pal; Pal; Pravati (1 February 2006). Textbook Of Practical Physiology (2nd ed.). Orient Blackswan. pp. 328–. ISBN 978-81-250-2904-5.
  3. Khurana (2008). Theory and Practice of Optics and Refraction. Elsevier India. p. 49.
  4. Colenbrander, August; Runge, Paul E. (May 2007). Can Jaeger Numbers be Standardized? (Poster 3563). Association for Research in Vision and Ophthalmology (ARVO) 2007 Annual Meeting, Fort Lauderdale. Investigative Ophthalmology & Visual Science. Vol. 48. p. 3563.
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