APERTURE TABLE. 
umerical 
aperture, 
jine « = NA 
Corresponding Angle 2 u for 
Limit of Resolving Power, in Lines to an Inch. 
Illuminating 
Power. 
(N A)2 
Pene- 
trating 
Power. 
1 
NA 
Air 
n = l ’ 00 . 
Water 
n = 1 • 33. 
Homogeneous 
Immersion 
n = 1-515. 
White Light. 
A = 0-5607 g. 
(Between 
D and E). 
Monochromatic 
Blue Light. 
A = 0-4861 u 
(Line F). 
Photography. 
A = 04341 fj. 
(Line H-y). 
1-515 
180 ° 0 ' 
137,672 
158,845 
177,822 
2-310 
•658 
1-51 
170 ° 41 ' 
136,766 
157,800 
176,652 
2-280 
•662 
1-50 
* 
163 ° 52 ' 
135,860 
156,755 
175,482 
2-250 
•667 
1 49 
159 ° 9 ' 
134,955 
155,710 
174,312 
2-220 
•671 
1-48 
• • 
155 ° 19 ' 
124,049 
154,665 
173,143 
2*190 
*676 
1-47 
152 ° 0 ' 
133,143 
153,620 
171,973 
2-161 
•680 
1-46 
149 ° 2 ' 
132,237 
152,575 
170,803 
2*132 
•685 
1 45 
146 ° 19 ' 
131,332 
151,530 
169,633 
2*103 
•690 
1-44 
143 ° 48 ' 
130,426 
150,485 
168,463 
2-074 
•694 
1-43 
141 ° 26 ' 
129.520 
149,440 
167,293 
2-045 
•694 
1-42 
139 ° 12 ' 
128,614 
148,395 
166,123 
2-016 
•709 
1-41 
137 ° 5 ' 
127,709 
147,350 
164,953 
1-988 
•709 
1-40 
135 ° 4 ' 
126,803 
146,305 
163,783 
1-960 
•714 
1-39 
133 ° 7 ' 
125,897 
145,260 
162,614 
1*932 
•719 
1-38 1 
131 ° 16 ' 
124,991 
144,215 
161,444 
1*904 
•725 
1 37 
129 ° 27 ' 
124,086 
143,170 
160,274 
1*877 
•729 
1-36 
127 ° 43 ' 
123,180 
142,125 
159,104 
1*850 
•735 
1-35 
126 ° 1 ' 
122,274 1 
141,080 
157,934 
1*823 
•741 
1-34 
124 ° 23 ' 
121,369 
140,035 
156,764 
1*796 
•746 
1 33 
180 ° 0 ' 
122 ° 47 ' 
120,463 
138,989 
155,594 
1*769 
•752 
1-32 
165 ° 56 ' 
121 ° 13 ' 
119,557 
137,944 
154,424 
1-742 
•758 
1-30 
155 ° 38 ' 
118 ° 12 ' 
117,746 
135,854 
152,085 
1*690 
•769 
1-28 
148 ° 42 ' 
115 ° 19 ' 
115,934 
133,764 
149,745 
1-638 
•781 
1-26 
142 ° 39 ' 
112 ° 33 ' 
114,123 
131,674 
147,405 
1-588 
•794 
1-24 
137 ° 36 ' 
109 ° 52 ' 
112,311 
129,584 
145,065 
1-538 
•806 
1-22 
133 ° 4 ' 
107 ° 16 ' 
110,500 
127,494 
142,726 
1-488 
*820 
1-20 
128 ° 55 ' 
104 ° 46 ' 
108,688 
125,404 
140,386 
1*440 
•833 
118 
125 ° 3 ' 
102 ° 19 ' 
106,877 
123,314 
138,046 
1*392 
•847 
116 
121 ° 26 ' 
99 ° 56 ' 
105,065 
121,224 
135,706 
1*346 
•862 
114 
118 ° 0 ' 
97 ° 37 ' 
103,254 
119,134 
133,367 
1*300 
•877 
M2 
114 ° 44 ' 
95 ° 20 ' 
101,442 
117,044 
131,027 
1-254 
•893 
110 
111 ° 36 ' 
93 ° 7 ' 
99,631 
114,954 
128,687 
1-210 
•909 
108 
108 ° 36 ' 
90 ° 56 ' 
97,819 
112,864 
126,347 
1-166 
•926 
106 
” 
105 ° 42 ' 
88 ° 48 ' 
96,008 
110,774 
124,008 
1124 
•943 
104 
102 ° 53 ' 
86 ° 42 ' 
94,196 
108,684 
121,668 
1-082 
•962 
102 
100 ° 10 ' 
84 ° 38 ' 
92,385 
106,593 
119,328 
1-040 
•980 
100 
180 ° 0 ' 
97 ° 31 ' 
82 ° 37 ' 
90,574 
104,503 
116,988 
1-000 
1-000 
0-98 
157 ° 2 ' 
94 ° 56 ' 
80 ° 37 ' 
88,762 
102,413 
114,648 
•960 
1-020 
0-96 
147 ° 29 ' 
92 ° 24 ' 
78 ° 38 ' 
86,951 
100,323 
112,309 
•922 
1-042 
0-94 
140 ° 6 ' 
89 ° 56 ' 
76 ° 42 ' 
85,139 
98,223 
109,969 
•884 
1064 
0-92 
133 ° 51 ' 
87 ° 32 ' 
74 ° 47 ' 
83,328 
96,143 
107,629 
*846 
1*087 
0 90 
128 ° 19 ' 
85 ° 10 ' 
72 ° 53 ' 
81,516 
94,053 
105.289 
•810 
1-111 
0-88 
123 ° 17 ' 
82 ° 51 ' 
71 ° 1 ' 
79,705 
91,963 
102,950 
*774 
1-136 
0 86 
118 ° 38 ' 
80 ° 34 ' 
69 ° 10 ' 
77,893 
89,873 
100,610 
•740 
1-163 
0-84 
114 ° 17 ' 
78 ° 20 ' ' 
67 ° 21 ' 
76,082 
87,783 
98,270 
*706 
1-190 
0-82 
110 ° 10 ' 
76 ° 8 ' 
65 ° 32 ' 
74,270 
85,693 
1 95,930 
*672 
1-220 
0-80 
106 ° 16 ' 
73 ° 58 ' 
63 ° 45 ' 
72,459 
• 83,603 
93,591 
•640 
1-250 
0*78 
102 ° 31 ' 
71 ° 49 ' 
61 ° 58 ' 
70,647 
81,513 
91 , 251 - 
•608 
1-282 
0-76 
98 ° 56 ' 
69 ° 42 ' 
60 ° 13 ' 
68,836 
79,423 
88,911 
*578 
1*316 
0-74 
95 ° 28 ' 
67 ° 37 ' 
58 ° 29 ' 
67,024 
77,333 
86,571 
*548 
1-351 
0-72 
1 92 ° 6 ' 
65 ° 32 ' 
56 ° 45 ' 
65,213 
75,242 
84,232 
•518 
1-389 
0-70 
88 ° 51 ' 
63 ° 31 ' 
55 ° 2 ' 
63,401 
73,152 
81,892 
•490 
1-429 
0-68 
85 ° 41 ' 
61 ° 30 ' 
53 ° 20 ' 
61,590 
71,012 
i 79,552 
•462 
1-471 
0-66 
! 82 ° 36 ' 
59 ° 30 ' 
51 ° 39 ' 
59,779 
68,972 
77,212 
•436 
1*515 
0 64 
79 ° 36 ' 
57 ° 31 ' 
49 ° 59 ' 
57,967 
66,882 
74,872 
•410 
1-562 
0-62 
76 ° 38 ' 
55 ° 34 ' 
48 ° 19 ' 
56,156 
64,792 
72,533 
•384 
1-613 
0-60 
73 ° 44 ' 
53 ° 38 ' 
46 ° 40 ' 
54,344 
62,702 
70,193 
•360 
1-667 
0-58 
70 ° 54 ' 
51 ° 42 ' 
45 ° 1 ' 
52,533 
60,612 
67,853 
•336 
1-724 
0-56 
68 ° 6 ' 
49 ° 48 ' 
43 ° 23 ' 
50,721 
58,522 
65,513 
•314 
1*786 
0-54 
65 ° 22 ' 
47 ° 54 ' 
41 ° 46 ' 
48,910 
56,432 
j 63,174 
•292 
1*852 
0-52 
62 ° 40 ' 
46 ° 2 ' 
40 ° 9 ' 
47,098 
54,342 
60,834 
•270 
1*923 
0-50 
60 ° 0 ' 
44 ° 10 ' 
38 ° 32 ' 
45,287 
52,252 
58,494 
•250 
2-000 
0-45 
53 ° 30 ' 
39 ° 33 ' 
34 ° 34 ' 
40,758 
47,026 
52,645 
•203 
2-222 
0-40 
47 ° 9 ' 
35 ° 0 ' 
30 ° 37 ' 
36,229 
41,801 
46,795 
•160 
2-500 
0 35 
40 ° 58 ' 
30 ° 30 ' 
26 ° 43 ' 
31,701 
36,576 
40,946 
•123 
2-857 
0 30 
34 ° 56 ' 
26 ° 4 ' 
22 ° 50 ' 
27,172 
31,351 
35,096 
•090 
3-333 
0-25 
28 ° 58 ' 
21 ° 40 ' 
19 ° 0 ' 
22,643 
26,126 
29,247 
•063 
4-000 
0-20 
23 ° 4 ' 
17 ° 18 ' 
15 ° 10 ' 
18,115 
20,901 
23,398 
•040 
5-000 
015 
17 ° 14 ' 
12 ° 58 ' 
11 ° 22 ' 
13,586 
15,676 
17,548 
•023 
6-667 
010 
11 ° 29 ' 
8 ° 38 ' 
7 ° 34 ' 
9,057 
10,450 
11,699 
•010 
10 000 
0-05 
5 ° 44 ' 
4 ° 18 ' 
3 ° 47 ' 
4,529 
5,252 
| 5,849 
•003 
20-000 
