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Dmitri Dmitrievich Maksutov
Dmitry Dmitrievich Maksutov (russian: Дми́трий Дми́триевич Максу́тов) ( – 12 August 1964) was a Russian / Soviet optical engineer and amateur astronomer. He is best known as the inventor of the Maksutov telescope. Biography Dmitry Dmitriyevich Maksutov was born in 1896 in either Nikolayev or the port city of Odessa, Russian Empire. His father, was a naval officer serving with the Black Sea Fleet, who came from a family with a long and distinguished naval tradition. His great-grandfather, Peter Ivanovich Maksutov, was given the title of prince, thereby raising the family to hereditary nobility as a reward for bravery in combat. His grandfather, Dmitri Petrovich Maksutov, was the last Russian governor of Russian Alaska, before it was purchased by the United States in 1867. Dmitri became interested in astronomy in early childhood, and constructed his first telescope (a 7.2 inch / 180 mm reflector) when he was twelve years old. Later he rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Engineering
Optical engineering is the field of science and engineering encompassing the physical phenomena and technologies associated with the generation, transmission, manipulation, detection, and utilization of light. Optical engineers use optics to solve problems and to design and build devices that make light do something useful. They design and operate optical equipment that uses the properties of light using physics and chemistry, such as lenses, microscopes, telescopes, lasers, sensors, fiber optic communication systems and optical disc systems (e.g. CD, DVD). Optical engineering metrology uses optical methods to measure either micro-vibrations with instruments like the laser speckle interferometer, or properties of masses with instruments that measure refraction Nano-measuring and nano-positioning machines are devices designed by optical engineers. These machines, for example microphotolithographic steppers, have nanometer precision, and consequently are used in the fabrication of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mirror
A mirror or looking glass is an object that Reflection (physics), reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the image in an equal yet opposite angle from which the light shines upon it. This allows the viewer to see themselves or objects behind them, or even objects that are at an angle from them but out of their field of view, such as around a corner. Natural mirrors have existed since prehistoric times, such as the surface of water, but people have been manufacturing mirrors out of a variety of materials for thousands of years, like stone, metals, and glass. In modern mirrors, metals like silver or aluminium are often used due to their high reflectivity, applied as a thin coating on glass because of its naturally smooth and very Hardness (materials science), hard surface. A mirror is a Wave (physics), wave reflector. Light consis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prism (optics)
An optical prism is a transparent optics, optical element with flat, polished surfaces that are designed to refraction, refract light. At least one surface must be angled — elements with two parallel surfaces are ''not'' prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides. Not all optical prisms are prism (geometry), geometric prisms, and not all geometric prisms would count as an optical prism. Prisms can be made from any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, acrylic glass, acrylic and fluorite#Optics, fluorite. A dispersive prism can be used to break white#White light, white light up into its constituent spectral colors (the colors of the rainbow) as described in the following section. Other types of prisms noted below can be used to reflection (physics), reflect light, or to split light into components with different polarization (w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Objective Lens
In optical engineering, the objective is the optical element that gathers light from the object being observed and Focus (optics), focuses the ray (optics), light rays to produce a real image. Objectives can be a single Lens (optics), lens or mirror, or combinations of several optical elements. They are used in microscopes, binoculars, telescopes, cameras, slide projectors, CD players and many other optical instruments. Objectives are also called object lenses, object glasses, or objective glasses. Microscope objectives The objective lens of a microscope is the one at the bottom near the sample. At its simplest, it is a very high-powered magnifying glass, with very short focal length. This is brought very close to the specimen being examined so that the light from the specimen comes to a focus inside the microscope tube. The objective itself is usually a cylinder containing one or more lenses that are typically made of glass; its function is to collect light from the sample. Magn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Questar Corporation
Questar Corporation is a company based in New Hope, Pennsylvania. It manufactures precision optical devices for consumer, industrial, aerospace, and military markets. Its telescopes produced for the consumer market are sold under the brand name "Questar". History Questar was founded in 1950 by Lawrence Braymer, who set up Questar to develop and market Maksutov telescopes and other optical devices for the consumer, industrial, and government customers. The Questar Standard telescope has been in production since 1954. Questars have been associated with many well-known scientists and other personalities; for example, in 1959, Wernher Von Braun purchased a telescope manufactured by the company. Products Questar produces telescopes for consumer, military, police, security, aerospace, and industrial applications. Products sold by Questar include 3.5” (89 mm) and 7” (178 mm) aperture Maksutov Cassegrain astronomical/terrestrial telescopes for the consumer market. For a wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meade Instruments
The Meade Instruments (also shortened to Meade) is an American multinational company headquartered in Watsonville, California, that manufactures, imports, and distributes telescopes, binoculars, spotting scopes, microscopes, CCD cameras, and telescope accessories for the consumer market. It is the world's largest manufacturer of telescopes. Besides selling under its "Meade" brand name, the company sells solar telescopes under the brand "Coronado". Origins and history Founded in 1972 by John Diebel, Meade started as a mail order seller of small refracting telescopes and telescope accessories manufactured by the Japan-based Towa Optical Manufacturing Company. Meade started manufacturing its own line of products in 1976, introducing 6" and 8" reflecting telescopes models in 1977. In 1980, the company ventured into the Schmidt-Cassegrain market that up to that time had been dominated by Celestron Corporation. Meade has a long history of litigation with other companies over infri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celestron
Celestron is an American company based in Torrance, California, United States, that manufactures telescopes and distributes telescopes, binoculars, spotting scopes, microscopes, and accessories manufactured by its parent company, the Synta Technology Corporation of Taiwan. History The predecessor of Celestron was Valor Electronics, an electronics and military components firm founded in 1955 by Tom Johnson. Johnson became involved with telescopes when he built a 6" reflecting telescope for his two sons. In 1960, Johnson established the "Astro-Optical" division of Valor, which would later become Celestron. By 1964, Johnson had founded "Celestron Pacific" as a division of Valor Electronics offering Schmidt-Cassegrain telescopes from 4" to 22". In 1970 Celestron introduced its "C8" 8" diameter 2032 mm focal length, ƒ10 telescope, the first of a new line of telescopes built using methods developed by Celestron to produce Schmidt-Cassegrains at a high volume and low cost. These m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meniscus Corrector Shell
A meniscus corrector is a negative meniscus lens that is used to correct spherical aberration in image-forming optical systems such as catadioptric telescopes. It works by having the equal but opposite spherical aberration of the objective it is designed to correct (usually a spherical mirror). Types Meniscus correctors are used as full aperture correctors, most commonly in a Maksutov telescope sub type called the Gregory or “spot” Maksutov–Cassegrain telescope. They are also used in the Bouwers meniscus telescope. There are Maksutov variations that use the same principle but place the meniscus lens as a sub-aperture corrector near the focus of the objective. There are other sub-aperture meniscus corrector catadioptric telescopes such as the Argunov–Cassegrain telescope and the Klevtsov–Cassegrain telescope. Invention The idea of using the spherical aberration of a meniscus lens to correct the opposite aberration in a spherical objective dates back as far as W. F. Ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lens (optics)
A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), usually arranged along a common axis. Lenses are made from materials such as glass or plastic, and are ground and polished or molded to a desired shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called lenses, such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses. Lenses are used in various imaging devices like telescopes, binoculars and cameras. They are also used as visual aids in glasses to correct defects of vision such as myopia and hypermetropia. History The word ''lens'' comes from '' lēns'', the Latin name of the lentil (a seed of a lentil plant), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspheric
An aspheric lens or asphere (often labeled ''ASPH'' on eye pieces) is a lens whose surface profiles are not portions of a sphere or cylinder. In photography, a lens assembly that includes an aspheric element is often called an aspherical lens. The asphere's more complex surface profile can reduce or eliminate spherical aberration and also reduce other optical aberrations such as astigmatism, compared to a simple lens. A single aspheric lens can often replace a much more complex multi-lens system. The resulting device is smaller and lighter, and sometimes cheaper than the multi-lens design. Aspheric elements are used in the design of multi-element wide-angle and fast normal lenses to reduce aberrations. They are also used in combination with reflective elements ( catadioptric systems) such as the aspherical Schmidt corrector plate used in the Schmidt cameras and the Schmidt–Cassegrain telescopes. Small molded aspheres are often used for collimating diode lasers. Aspheric lenses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spherical Aberration
In optics, spherical aberration (SA) is a type of optical aberration, aberration found in optical systems that have elements with spherical surfaces. Lens (optics), Lenses and curved mirrors are prime examples, because this shape is easier to manufacture. Light rays that strike a spherical surface off-centre are refraction, refracted or reflection (physics), reflected more or less than those that strike close to the centre. This deviation reduces the quality of images produced by optical systems. Overview A spherical lens has an Optical aberration#Aberration of elements, i.e. smallest objects at right angles to the axis, aplanatic point (i.e., no spherical aberration) only at a radius that equals the radius of the sphere divided by the index of refraction of the lens material. A typical value of refractive index for crown glass is 1.5 (see List of refractive indices, list), which indicates that only about 43% of the area (67% of diameter) of a spherical lens is useful. It is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schmidt Telescope
Schmidt may refer to: * Schmidt (surname), including list of people with the surname * Schmidt (singer) (born 1990), German pop and jazz singer * Schmidt (lunar crater), a small lunar impact crater * Schmidt (Martian crater), a crater on Mars * Schmidt (volcano), in Kamchatka * Schmidt Block, listed on the National Register of Historic Places in Scott County, Iowa, USA * Schmidt Brewery, a St. Paul brewery * Schmidt camera, an astronomical telescope designed for photography * Schmidt–Cassegrain telescope, a version of the Schmidt camera * Schmidt Site, an archeological site in Michigan, USA, listed on the National Register of Historic Places in 1973 * Schmidt Spiele, a German games manufacturer * Schmidt Baking Company, makers of Schmidt's Blue Ribbon Bread * von Schmidt auf Altenstadt, a German baronial family in Kirchgattendorf, part of the municipality of Gattendorf * Schmidt Island, an island in the Novaya Zemlya archipelago in the Arctic Ocean * Schmidt Peninsula (Sakhal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
