Parabolic Mirror
A mirror with a parabolic reflective surface.
If a “point light source” is placed at its focus, the light will be reflected by the mirror and emitted parallel to the main axis of the mirror; searchlights and car headlights are equipped with parabolic mirrors, which apply this principle to obtain parallel light beams for easy lighting. Conversely, if light parallel to the main axis is projected onto the mirror, it will converge to its focus after reflection; reflecting astronomical telescopes are equipped with parabolic mirrors, which apply this principle to form images of distant celestial bodies for easy observation.
Definition of Parabolic Mirror
A parabolic mirror, also called a parabolic dish or an object reflector, is usually a reflective device made of a shape formed by the rotation of a parabola.
The name of the parabolic mirror comes from the geometric shape of the parabola: if the angle of incidence on the inner surface of the collector is equal to the angle of reflection, then any incident light parallel to the optical axis of the dish will be reflected to the focus. Because many types of energy can be reflected in this way, parabolic reflectors can collect and concentrate the energy entering the reflector to a specific angle. Similarly, the energy radiated from the focus of the disk can also be transmitted as a beam parallel to the axis of the disk.
Application of parabolic mirrors
Daily life
When the light source is at the focus, the light is reflected by the mirror and becomes a parallel beam. Car lights and searchlights are equipped with parabolic mirrors.
Parabolic reflectors can collect or distribute energy from light, radio waves or sound waves. Parabolic reflectors are most commonly used in modern satellite signal receivers, telescopes (including radio telescopes), parabolic microphones, and many lighting equipment, such as spotlights, car lights, PAR Cans and LED shells.
Astronomy
John Hadley introduced parabolic mirrors to practical astronomy. In 1721, he used parabolic mirrors to make a reflecting telescope with very small spherical aberration. Before that, telescopes used spherical mirrors. Lighthouses also usually used parabolic mirrors to collimate the point light source from lanterns into a beam before being replaced by more efficient Fresnel lenses in the 19th century.
The aberration of a parabolic reflector is called coma, and it occurs mainly in telescopes, since most other applications do not require resolution (sharpness) away from the parabola’s axis.
How Parabolic Mirrors are Made
Turning a reflective liquid, like mercury, can form a parabolic reflector that points upward. This could potentially be used to make a liquid mirror telescope.
ABOUT BORISUN
Hanzhong Brisun Optics Co., Ltd. Is the high precision optical element manufacturer provides customized production of Various optical lenses, including spherical lens, cylindrical lens, optical window, mirror, prism, filter, metal base mirror and other high-precision optical elements. The base materials include various optical glass, fused quartz, calcium fluoride (CaF2), zinc selenide (ZnSe), germanium (GE), silicon (SI), sapphire, metal and other materials. And provide antireflective film, high reflection film, spectroscopic film, metal film and other optical coatings.
Welcome to OEM and Purchasing!
Recent Posts
Send Requests