WITH NOTATIONS FOR TESTING AT 3 METERS (10 FEET)
ACTUAL ACUITY DECI- Log
LETTER SIZE 3/METER 10/FOOT MAL MAR
1 15 M 3/15 10/50 0.20 0.7
2 12 M 3/12 10/40 0.25 0.6
3 9.5 M 3/9.5 10/32 0.32 0.5
4 7.5 M 3/7.5 10/25 0.40 0.4
5 6 M 3/6 10/20 0.50 0.3
6 4.8 M 3/4.8 10/16 0.63 0.2
7 3.8 M 3/3.8 10/12.5 0.80 0.1
8 3 M 3/3 10/10 1.00 0.0
9 2.4 M 3/2.4 10/8 1.25 -0.1
10 1.9 M 3/1.9 10/6.3 1.60 -0.2
11 1.5 M 3/1.5 10/5 2.00 -0.3
12 1.2 M 3/1.2 10/4 2.50 -0.4
1 1 1 1
2 2 2 2
3 3 3 3
4 4 4 4
5 5 5 5
6 6 6 6
7 7 7 7
8 8 8 8
9 9 9 9
10 10 10 10
11 11 11 11
12 12 12 12
FOR TESTING AT 40 CM (16 INCHES)
SNELLEN DISTANCE EQUIVALENT
LETTER SIZE DECIMAL METER FOOT DIOPTERS OF ADD FOR 1 M
A 8.0 M 0.050 6/120 20/400 20 D
B 6.3 M 0.063 6/95 20/320 15 D
C 5.0 M 0.080 6/75 20/250 12 D
D 4.0 M 0.10 6/60 20/200 10 D
E 3.2 M 0.12 6/48 20/160 8 D
F 2.5 M 0.16 6/38 20/125 6 D
G 2.0 M 0.20 6/30 20/100 5D
H 1.6 M 0.25 6/24 20/80 4 D
I 1.25 M 0.32 6/19 20/63 3 D
J 1.0 M 0.40 6/15 20/50 2.5 D
K 0.80 M 0.50 6/12 20/40
L 0.63 M 0.63 6/9.5 20/32
M 0.50 M 0.80 6/7.5 20/25
N 0.40 M 1.00 6/6 20/20
O 0.32 M 1.25 6/4.8 20/16
P 0.25 M 1.60 6/3.8 20/12.5
R 0.20 M 2.00 6/3 20/10
A A A A
B B B B
C C C C
D D D D
E E E E
F F F F
G G G G
H H H H
I I I I
J J J J
K K K K
L L L L
M M M M
N N N N
O O O O
P P P P
R R R R