图形对比敏感度卡 wi127215 wi127215

LEA SYMBOLS® Low Contrast Test, 10M

Test for quick measurement of low contrast visual acuity at 25%, 10%, 5%, 2.5%, and 1.25% contrast by measuring the distance where the symbols are seen. 10M symbols correspond to visual acuity 0.10 at 1 m, 0.05 at 0.5 m and 0.3 at 3 m. VA values are thus easy to calculate. Test includes a table for conversion to Snellen equivalent VA values, a response key, training cards, recording forms and instructions. 6 pages, 3.25" x 9" (8.25 cm x 22.9 cm).