Shades or sun glasses are a type of defensive eyewear planned basically to avoid splendid daylight and high-vitality unmistakable light from harming or discomforting the eyes. They can in some cases likewise work as a visual guide, as differently named exhibitions or glasses exist, highlighting focal points that are hued, enraptured or obscured. In the mid twentieth century, they were otherwise called sun con artists (con artists being an American slang term for glasses). A focal point is a transmissive optical gadget that concentrations or scatters a light shaft by methods for refraction. A basic focal point comprises of a solitary bit of straightforward material, while a compound focal point comprises of a few basic focal points (components), normally orchestrated along a typical pivot. Focal points are produced using materials, for example, glass or plastic, and are ground and cleaned or formed to a coveted shape. A focal point can concentrate light to frame a picture, not at all like a crystal, which refracts light without centering. Gadgets that likewise center or scatter waves and radiation other than obvious light are additionally called focal points, for example, microwave focal points, electron focal points, acoustic focal points, or touchy focal points.