Question

You get a summer internship working with a 589.2nm laser (an intense light source with a very well defined wavelength). You want to spray some oil with noil=1.25 on your glasses with nglass=1.50 as an additional safety feature to protect you from accidental flashes of laser light.Your applicator can only spray films thicker than 600nm. What is the thinnest film you can spray with the applicator given above that protects your eyes from the laser light beam?