This lesson will give you an overview of some of the many optical devices and inventions that we have. Materials that light passes through Light easily passes through air and glass. Such materials are called transparent . There are some materials that only allow some of the light to pass through them. If only a percentage of the light can pass through, the material is called translucent .
Some materials only allow selected wavelengths to pass through.
Colored glass may block some colors, while allowing only one or two specific wavelengths to pass through it. It is obvious that it doesn't pass through materials like steel or wood. The ray model of light Light normally travels in a straight line. The two angles are equal, and this is called the Law of Reflection . For example, when light hits a flat mirror, the angle of reflection is the same as the incoming angle.