Light Optics!!! Need help please!!! When a blue light from a certain filtered light source is passed through a deffraction grid with 1000 slits per cm, it produces a pattern of fringes on a screen. If the screen is placed .25 meters form the grid, find the wavelength of the blue light. I have no idea how to even start this problem let alone solve. My teacher's philosophy is too make us do the hw for sections we havent done first then talk about and the book is of no help either. Any help would be great!!!