When light interacts or hits any surface two things happen, it’s either the light is reflected or the light is refracted. The main difference between mirror and lens is that the image forms by reflection, as the light falls on a mirror while in the lens, the image is formed by refraction. Optical lenses are polished surfaces like glass that transmit light. This lens comes both coated and uncoated depending on the use just like laser optics windows. A lens is a transparent device with two curved surfaces, usually made of glass or plastic substrate, that uses refraction to form an image of an object. Now the is a system of lenses and mirrors which forms an image by gathering rays from an object and then causes them to converge or diverge. The formation of this image depends on the area where the image is formed or the origin of the image. A real image is formed when the optical system causes the rays to converge to a point, a virtual image is formed at the location from which they seem to originate. All-optical lenses have a focal length which is the distance between the lens and the focal point along the optical axis of the lens. When calculating the focal length, three factors need to be taken into consideration which includes the radius of curvature of the lens, the refractive index of the substrate from which the lens is made, the medium in which the lens resides, and the focal length of a lens. When dealing with optical lens mirrors some basic laws should be in your mind for guidance, Snell`s law of refraction, the law of reflection, and the law of dispersion.
Convex Lenses
A convex lens is a lens that principally converges rays of light traveling in a parallel pattern at a single axis. The orientation of the lens makes it curve outward. This lens converges a beam of parallel rays to a point on the other side of the lens called a focus of the lens and its distance from the Optical Center of the beam is called the focal length. The convex lens comes in different types like a plano-convex lens which comes with one plane surface and curved outward at the other surface with a positive focal length. Double convex lens or biconvex or convex is curved outward from both sides, this has no plain surface with a shorter focal length than plano-convex and the principle of a double convex lens is used in the projector, monocular, Telescope, cameras, etc. Lastly is the convex-concave lens which conforms with its name as it curves inward from one side and outward on the other side. Alpine research optics is a precision optical manufacturing companies.
Concave Lenses
The concave lens has one of its sides curved inward. It is a diverging lens, which makes it to spreads out light rays that have been refracted through it. A concave lens is thinner at its center than at its edges and is used to correct short-sightedness (myopia) eye defects. This lens comes in different types like a Plano concave lens which has one surface curved inward, and the other surface is flat, biconcave lens, convex-concave lens.
Convex Mirrors
Convex mirrors reflect light outwards (diverging light rays) and therefore they are not used to focus light thereby making the image to be erect and smaller.
Convex/Concave Mirrors
Convex/concave mirror is reflecting light, as opposed to transmitting light, the focal point is reversed, and this is obtained by adding a reflective coating.
Concave Mirrors
The surface that collects collimating light is curved inward.
