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March 4, 2025

Precision Vision ETDRS® Illuminator Cabinet Guide for Clinical Trials and Vision Research

  February 27, 2025 Precision Vision’s ETDRS® Illuminator Cabinet – The international gold standard for clinical trials and vision research ...

Introduction to Visual Acuity Measurement


by August Colenbrander, MD – San Francisco

Since the 1970’s Precision Vision has built a reputation of producing the most accurate and most durable vision testing tools available.  In the 1980’s they printed the first ETDRS cards and produced the standard ETDRS illuminator cabinet.  Since the early 1990’s they have carried a variety of Low Vision and pediatric testing tools.

This introduction is meant to provide some guidance in selecting from the vast array of charts and devices available.  It is divided into several sections.

A – Visual acuity
B – Letter chart measurements
C – Near Vision and Reading
D – Contrast Sensitivity
E – Low Vision tests
F – Pediatric tests

Click on the link below to get started.

To read this in it’s entirety, please click here.

A more detailed discussion is available in:Measuring Vision and Vision Loss, A. Colenbrander, in: Duane’s Clinical Ophthalmology, Vol 5, Ch. 51, ed. 2001 and later.