RRB RPF RPSF SI and CONS Model Papers 8 with solutions

(2) The first laser (light amplification by stimulated emission of radiation) was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow. Maiman’s functional laser used a solid-state flashlamp-pumped synthetic ruby crystal to produce red laser light, at 694 nanometers wavelength.