Question

Infrared radiation exposures of 200 W/cm2 at 1090 nm for 8 seconds with a continuous-wave glass fibre laser is demonstrated to induce cataract in less than a week. Whereas a similar experiment using 96 W/cm2 for 1 hour has shown no cataract after 1 week. If the first infrared laser intensity was measured at 300 mm, at what distance is considered safe for not developing cataract after 1 week? (4 marks)

Answer 1

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-139 x (o2 A 3 00 こん 2 8000 0 w/m T cucle tea catarac is not imd ve nee d to formed Le 0000 96000 0 0000 ここ入 60000 0.433 w 1 distauce fa Saffe 433mw °Rarer expasure