Дифракционная решетка

When we shine a flashlight on a CD, white color decomposes into rainbow. This phenomenon caused by wave nature of light. Surface of a CD has a finely-spaced data tracks. Every track works as reradiator. In those directions where reradiated waves in one phase they sums up and enhance each others. If you shine a monochromatic light laser in those directions, we will see bright colour stripes. When we shine CD with broad spectrum source evely wave length has their own spot and together they are a rainbow spectrum. PASCO equipment was used.