Table I
Spectral steradiancy of the flash source at peak radiance as determined by comparison with a standard tungsten-ribbon filament lamp operated at 3000° color temperature. The tungsten values were interpolated from the measurements of Barnes and Forsythe (see Ref. 3).
(1) (λ) at Tmax of interference filter | Ratio of flash source radiance to radiance of tungsten ribbon | Spectral steradiancy in W/cm2/10-mμ band |
---|
(2) 919 phototube | (3) 929 phototube | (4) mean | (5) tungsten | (6) flash source |
---|
423 | | 1653 | 1653 | 0.0357 | 59.01 |
434 | 3373 | 1668 | 2521 | 0.0420 | 105.88 |
435 | | 2257 | 2257 | 0.0425 | 95.92 |
444 | | 2195 | 2195 | 0.0488 | 107.12 |
458 | | 2320 | 2320 | 0.0565 | 131.08 |
465 | | 1505 | 1505 | 0.0612 | 92.11 |
477 | 2533 | 2351 | 2442 | 0.0700 | 170.94 |
503 | 1184 | 1461 | 1322 | 0.0887 | 117.26 |
510 | 1130 | 1336 | 1233 | 0.0935 | 115.29 |
533 | 1178 | 1131 | 1154 | 0.1140 | 131.56 |
554 | 859 | 895 | 878 | 0.1275 | 111.95 |
555 | 879 | 881 | 880 | 0.1282 | 112.82 |
570 | 695 | 788 | 741 | 0.1398 | 103.59 |
580 | 624 | 592 | 608 | 0.1475 | 89.68 |
622 | | 431 | 431 | 0.1781 | 76.76 |
640 | 431 | 377 | 404 | 0.1905 | 76.96 |
658 | 394 | 390 | 392 | 0.2011 | 78.83 |
686 | | 441 | 441 | 0.2170 | 95.70 |
701 | 329 | | 329 | 0.2250 | 74.03 |
828 | 300 | | 300 | 0.2632 | 78.96 |
887 | 429 | | 429 | 0.2710 | 116.26 |
1005 | 898 | | 898 | 0.2554 | 229.35 |
1015 | 860 | | 860 | 0.2538 | 218.27 |
1050 | 834 | | 834 | 0.2475 | 206.42 |
Table II
Integrated energy in flashes of various durations chopped from the peak radiance of the flash-tube discharge. The durations are given in terms of an equivalent square-wave flash; they are measured from the half-intensity points of the actual flash. The retinal irradiance and retinal illuminance values neglect losses in the ocular media.
Duration msec | Retinal illuminance photopic td · sec | Retinal irradiance cal/cm2 |
---|
1.4 | 3×107 | 0.0120 |
0.56 | 1.2×107 | 0.0048 |
0.24 | 5.2×106 | 0.0021 |
0.10 | 2.2×106 | 0.0009 |
0.042 | 9.1×105 | 0.0004 |
Table III
The effect of removing the infrared on the recovery times for a 0.07-mL test letter subtending a visual angle of 20.4 min of arc.
Subject | KG-3 filter 9.8×106 td · sec | 0.13 Neutral density 9.8×106 td · sec | No filter 1.3×107 td · sec |
---|
J. C. | 51.6 | 63.2 | 51.4 |
54.3 | 61.8 | 60.6 |
80.3 | 42.3 | 58.0 |
57.5 | 42.1 | 59.3 |
| | | |
L. L. | 118.0 | 75.3 | 110.6 |
101.3 | 94.7 | 127.6 |
115.5 | 92.8 | 173.1 |
126.6 | 117.0 | 155.0 |
| | | |
D. H. | 35.4 | 42.0 | 48.4 |
38.0 | 45.2 | 51.4 |
40.1 | 40.4 | 61.9 |
39.1 | 38.3 | 60.7 |
| | | |
E. H. | 40.0 | 35.0 | 71.0 |
51.0 | 53.5 | 71.2 |
52.0 | 61.7 | 70.7 |
54.7 | 50.3 | 67.8 |
| | | |
V. K. | 56.4 | 68.4 | 57.7 |
66.5 | 64.6 | 64.8 |
62.2 | 64.5 | 73.0 |
66.3 | 62.5 | 75.7 |
| | | |
Means | 65.34 | 60.78 | 78.50 |
Table IV
The effect of field size and exposure duration on the recovery times for identification of a 0.07-mL test letter subtending 16.3′ visual angle following flashes of 4.0×105 L. The recovery times are given in seconds and are the means for five subjects.
Exposure duration msec | (neglecting losses in ocular media) td · sec | Field size | Means for the four larger fields |
---|
10.0° | 7.5° | 5.0° | 2.5° | 20′ |
---|
0.04 | 9×105 | 14.49 | 16.41 | 14.02 | 11.96 | 8.05 | 14.22 |
0.10 | 2.2×106 | 32.07 | 25.40 | 24.46 | 29.62 | 10.15 | 27.89 |
0.24 | 5.2×106 | 42.94 | 49.28 | 47.89 | 67.77 | 5.67 | 51.97 |
0.56 | 1.2×107 | 65.42 | 65.26 | 95.79 | 70.31 | 16.02 | 74.19 |
1.40 | 3×107 | 110.02 | 113.61 | 99.56 | 115.66 | 43.77 | 109.71 |
Table V
Summary of the analysis of variance for the effect of field size and exposure duration on recovery times following flashes of 4×105 L.
Source | df | Mean square | f/number | Significance level |
---|
(1) Subjects | 4 | 2738.46 | | |
(2) Exposures | 4 | 28832.89 | 47.22 | <0.1% |
(3) Field sizes | 3 | 182.55 | 3.48 | 5% |
(4) Subjects×Exposures | 16 | 610.64 | 1.39 | ⋯ |
(5) Subjects×Fields | 12 | 52.44 | 0.12 | ⋯ |
(6) Exposures×Fields | 12 | 461.03 | 1.05 | ⋯ |
(7) Exposures×Fields×Subjects | 48 | 439.10 | | |
(8) Total | 99 | 1622.07 | | |
Table VI
Individual means of recovery times for a 0.07-mL letter subtending 16.3′ visual angle following 4.0×105 L flashes of various durations. Four flashes of each duration were presented.
Subject | 0.04 msec | 0.10 msec | 0.22 msec | 0.56 msec | 1.40 msec |
---|
Order of flashes: from long to short |
V. K. | 31.75 | 40.40 | 76.75 | 48.85 | 170.22 |
J. C. | 60.60 | 38.75 | 55.10 | 100.22 | 162.95 |
D. H. | 34.40 | 59.07 | 40.57 | 63.10 | 101.90 |
D. M. | 9.60 | 16.90 | 28.10 | 46.93 | 93.22 |
L. L. | 11.62 | 17.25 | 61.58 | 115.10 | 177.92 |
|
Mean | 29.59 | 34.47 | 52.42 | 75.84 | 141.24 |
|
Order of flashes: from short to long |
V. K. | 14.55 | 85.48 | 70.42 | 170.95 | 213.88 |
J. C. | 8.95 | 14.47 | 16.75 | 53.88 | 116.30 |
D. H. | 29.80 | 44.15 | 48.25 | 102.95 | 145.72 |
D. M. | 9.57 | 18.60 | 22.47 | 35.65 | 81.42 |
L. L. | 14.95 | 12.97 | 22.45 | 39.55 | 120.82 |
|
Mean | 15.56 | 33.13 | 36.07 | 80.60 | 135.63 |
Table VII
Mean recovery times for four subjects for various letter sizes presented at 0.07 mL.
Flash energy (log td · sec) | Angular subtense of letter |
---|
42′ | 28.4′ | 20.4′ | 16.3′ |
---|
7.49 | 58.95 | 73.30 | 90.10 | 123.07 |
7.06 | 37.05 | 48.67 | 65.90 | 85.75 |
6.71 | 18.55 | 22.25 | 34.70 | 45.88 |
6.37 | 11.12 | 13.30 | 18.85 | 22.30 |