This preview shows page 1. Sign up to view the full content.
Unformatted text preview: 5(a) What is the average number of round trips for a photon in a laser with mirror reflectances of 100% for the back mirror and 40% for the front mirror? (2 marks) (b) If the optical cavity length is 1.5 m, with is the cavity lifetime? (2 marks) 6. US Homeland security is worried that pilots may be blinded by people point laser points at distant airplanes. The most powerful laser pointer on the market is the BigHa pointer which has a 5 mW beam at 533 nm with w=1 mm. (a)What is the Rayleigh Range of the pointer? (b) What is distance where the beam average power density has reduced to 0.5mW/mm 2 . (c) If an airplane is 1 km from the pointer, what is the spotsize at the plane, its average power density and peak power density? 7 Calculate the approximate peak wavelengths from expected from the following materials given their bandgaps: GaAs (1.44 eV), GaP (2.26 eV) CdTe (1.50 eV), InP (1.35 ev), SiC (3.00 eV)...
View Full Document
This note was uploaded on 11/22/2010 for the course ENSC 470 taught by Professor Chapmann during the Spring '10 term at Simon Fraser.
- Spring '10