City of Light: The Story of Fiber Optics

286 NOTES TO PAGES 44–50
of Munich (Martin Carey, personal communication). Interestingly, Schindler knew
where Lamm was working in the late 1950s, but the two were not in regular
contact, and there is no evidence Schindler ever told Lamm about the later successful
gastroscope.
39. Lamm, ‘‘Biegsame optische Geräte,’’ p. 581.
40. Schindler, whose father was Jewish, spent six months in jail before emigrating
to America. Davis, ‘‘Rudolf Schindler’s role.’’
41. Rudolf Hecht, telephone interview, Sept. 27, 1994.
42. Michael Lamm, telephone interview, Sept. 24, 1994.
43. Hecht interview; ‘‘Dr. H. Lamm,’’ obituary, Texas Medicine, Mar. 1975,
p. 120.
Chapter 5
1. Date from Lewis Hyde (interview, Feb. 15, 1993), who says van Heel was
in Rochester Oct. 18–28, 1951.
2. O’Brien’s son, an optical engineer who had a security clearance and sometimes
worked with his father, was also present. Brian O’Brien, Jr., telephone interview,
Sept. 12, 1994.
3. Willem Brouwer, interview, Jan. 12, 1994.
4. Lewis Hyde, telephone interview, Feb. 28, 1994.
5. Walter P. Siegmund and F. Dow Smith, ‘‘Brian O’Brien—pioneer in optics,’’
Optics & Photonics News, Mar. 1993, pp. 48–51.
6. Brian O’Brien, Jr., interview, Feb. 4, 1994.
7. I calculated the number assuming light entering at a 5 degree angle to the
axis of a 50-micrometer glass fiber with refractive index of 1.5.
8. O’Brien, Jr., interview, Feb. 4, 1994, telephone interview, Apr. 5, 1994.
9. The smaller the refractive-index difference, the steeper the critical angle for
total internal reflection. However, even a one percent difference leaves a critical
angle of eight degrees in glass, and that was enough for practical purposes.
10. W. S. Stiles and B. H. Crawford, ‘‘The luminous efficiency of rays entering
the eye pupil at different points,’’ Proceedings Royal Society of London B112,
pp. 428–450 (1933).
11. Ernst W. von Brücke, ‘‘Die physiologische Bedeutung des stabförmigen
Körper und der Zwillingszapfen in den Augen der Wirbelthiere’’ (‘‘The physiological
meaning of rods and cones in the eyes of vertebrates’’), Müller’s Archiv fur
Anatomie und Physiologie 11, pp. 444–451 (1844), translated by Susanna Lammert.
Von Brücke was trying to explain why some animal eyes look bright. He
did not cite Colladon’s light guiding demonstration, but the timing suggests it
could have influenced him.
12. Brian O’Brien, ‘‘Vision and resolution in the central retina,’’ Journal of the
Optical Society of America 41, No. 12, pp. 882–894 (Dec. 1951).
13. ‘‘Brian O’Brien, Frederic Ives Medalist for 1951,’’ Journal of the Optical
Society of America 41, No. 12, pp. 879–881 (Dec. 1951).
14. O’Brien, Jr., interview, Feb. 4, 1994; an engineer, he was visiting his father
at the time and had a clearance because he had worked with him on several
military programs.
15. H. Møller Hansen, Danish patent application 1094/51, ‘‘Flexible picture
transport cable,’’ Apr. 11, 1951 (in Danish, translated by Jonathan D. Beard).