The Maksutov (also called "bb> Mak ") is a catadioptric telescope design that incorporates a round mirror with a weak negative meniscus lens in a design that takes advantage of all surfaces to be virtually "symmetrically spherical". Negative lenses are usually full-diameter and placed in the pupil entrance of the telescope (commonly called "corrector plate" or "corrector of meniscus corrector"). The design corrects the problem of off-axis irregularities such as coma found in reflecting telescopes while also correcting chromatic aberration. It was patented in 1941 by the Russian optician Dmitri Dmitrievich Maksutov. Maksutov based his design on the idea behind the Schmidt camera using ball errors from the negative lens to correct the opposite error in the main mirror of the ball. This design is most often seen in Cassegrain variations, with integrated secondary, which can use all round elements, thus simplifying fabrication. The Maksutov telescope has been sold in the amateur market since the 1950s.
Video Maksutov telescope
Discovery
Dmitri Maksutov may have worked with the idea of ​​pairing the main mirror round in relation to negative meniscus lenses as far back as 1936. His notes from that time on the mirror function of Mangin, the initial catadioptric reflection spotlight consisting of a negative lens with silver on the back side, including a Mangin mirror sketch with a section mirrors and negative lenses separated into two elements. Maksutov seems to have taken the idea again in 1941 war-torn Europe as a variation on previous designs that paired a round mirror with a negative lens, Bernhard Schmidt's 1931 "Schmidt Camera". Maksutov claims to have come up with the idea of ​​replacing the complex Schmidt plates plate with an all-spherical "meniscus corrector" plate on a train ride from a refugee from Leningrad. Maksutov was described as patenting his designs in May, August, or October 1941 and constructing the prototype "Maksutov-Gregorian" in October 1941. Maksutov invented the unique idea of ​​using "achromatic corrector", a corrector made of one type of glass with a negative meniscus shape weakness that departs from the symmetrical form of pure concentric spheres to correct the chromatic aberration.
The design of a similar independent meniscus telescope was also patented in 1941: Albert Bouwers (concentric meniscus telescope 1941), K. Penning and Dennis Gabor (non-monocentric katadioptrik design). The secrecy of the wartime made these inventors know about their respective designs, leading to each being an independent discovery.
Maps Maksutov telescope
Derived design
Maksutov's design for the meniscus telescope was first published, appearing in the Journal of the American Optical Society Vol. 34, No. 5. May 1944 in a paper written by Maksutov entitled the New Catanioptric Meniscus System . This led to professional and amateur designers soon experimenting with variations, including Newtonian, Cassegrain, and wide-field camera design.
Maksutov-Cassegrains
There are many Maksutov designs that use the Cassegrain configuration, installing a secondary mirror convex near the main mirror focus. Most types use a full-aperture corrector and therefore are not very large, because the corrector plate quickly becomes very large, heavy and expensive as the aperture increases, with very long cooling times to achieve optimum optical performance. Most commercial manufacturers usually stop at 180 mm (7 inches).
Gregory or "places" Maksutov-Cassegrains
Maksutov's design record from 1941 explored the possibility of folded 'Cassegrain-type' construction with a silver spotted secondary on the convex side of the meniscus facing the main mirror. He thinks this will create a sealed and coarse optical system that is suitable for use in schools. This design appeared commercially in the Lawrence Lawrenceman 1954 Lawrence Braymer telescope and in the competing patent Perkin-Elmer designer John Gregory for a Maksutov-Cassegrain. The commercial use of the Gregory design is explicitly reserved for Perkin-Elmer but is published as an amateur telescope design in the 1957 edition of Sky and Telescope in f /15 and f /23 variations. Most Maksutov produced today are the 'Cassegrain' design type (referred to as "Gregory-Maksutov" or "Spot-Maksutov") which uses all round surfaces and has, as a secondary, a small aluminized point on the inner surface of the corrector. This has the advantage of simplifying construction. It also has the advantage of improving the secondary alignment and eliminating the need for 'spiders' that will cause diffraction spikes. The disadvantage is that, if all spherical surfaces are used, the system must have a focal ratio above f /15 to avoid deviations. Also, the degree of freedom in correcting the optical system by changing the radius of secondary curvature is lost, because the fingers are the same as those on the rear meniscus face. Gregory himself, in the second design, is faster ( f /15), using the aspherization surface of the front corrector (or main mirror) to reduce the deviation. This has led to other designs with asferic or additional elements to reduce off-axis irregularities. This type of high focal ratio of Maksutov-Cassegrain and this narrow field of view makes them more suitable for moon and planet imaging and other types of observations where a narrow, high-power view of the field is a plus, such as solving globular clusters and multiple stars.
The most famous type of early amateur astronomy was the Questar 3-1/2 Maksutov Cassegrain introduced in 1954, a small, well-run, expensive model still available in the consumer market. The mid-1970s saw the introduction of mass production models by several major commercial producers. Recently, Russia's low cost and, more recently, China's mass production has pushed prices down further. Many manufacturers currently produce Maksutov-Cassegrain, such as Explore Scientific, Intes, Intes-Micro, LOMO, Orion Optics, Telescope Engineering Company (TEC), Vixen, Meade Instruments ETX lines and Synta Taiwan produce Celestron, Sky-Watcher and Telescope Lines Orion.
The design of the Maksutov-Cassegrain venue has been used extensively in military, industrial, and aerospace applications. Since all the optical elements can be permanently aligned and the tube assemblies can be sealed with the environment, the design is very rough. It makes them ideal for tracking, remote viewing, and radar/boresighting calibration in which instruments are subjected to severe environments and high g-forces.
Rutten Maksutov-Cassegrains
The Rutten Maksutov-Cassegrain (also called Rumak or Sigler Maksutov ) has a separate secondary mirror mounted on the inner surface of the meniscus support, sometimes similar to the holder/mirror configuration holder found in commercial Schmidt-Cassegrain. This provides an extra level of freedom in correcting irregularities by changing the curvature of the corrector and secondary independently. In particular it allows designers to hone secondary to provide a much wider flat field than the traditional Maksutovs place, with fewer off-axis coma. Installing the secondary on the corrector also limits the diffraction spikes. This version was named after the work of Dutch optical designer Harrie Rutten.
Maksutov-Cassegrains sub-aperture sub-aperture_corrector_Maksutov- Cassegrains ">
Maksutov notes in his design that instead of using a full-aperture corrector, a small sub-slit corrector can be placed in the converging light cone of the main mirror and achieve the same effect. In the 1980s Dave Shafer and Ralph W. Field came out with a Cassegrain sub-aperture design based on this idea. The design reduces the mass and "cooling time" of the full aperture corrector. It has an open tube weakness, is not enclosed and requires spider assembly to withstand secondary mirrors and corrector, which undoubtedly affects the image quality through diffraction artifacts. Also because the light passes through the corrector twice, the number of involved surfaces increases, making it difficult to achieve a good aberration correction. Maksutovs sub-openers are currently produced by the Vixen telescope, their VMC (Vixen Maksutov Cassegrain) model.
Maksutov Newtonians
Maxutovs optics can be used in a Newton configuration that has a minimum deviation over a wide field of view, with a quarter semen of a Newtonian and a semicircic alike from Schmidt-Newtonian. Diffraction can also be minimized by using high focal ratios with small diagonal mirrors mounted on the corrector, enabling this design to achieve contrast and close-up image quality from unstoppable high-end refractors (albeit with some vignetting when used photographically). Like Maksutov-Cassegrain, the overall diameter of the optical system is limited, due to the mass of the corrector plate. Synta Taiwan currently produces a 190mm version under the Sky-Watcher brand as well as the 152mm Explore Scientific with a design designed to work with astronomer David Levy.
Camera Maksutov
The Maksutov system can be used in a very rare kind of ultra-wide astronomy camera design similar to a Schmidt camera. Like the Schmidt camera, the Maksutov camera has a curved focus field.
See also
- List of telescope types
- List of Russian discoveries
References
External links
- Maksutov's design evolution
- Maximum Photovisual Cassegrain Telescope
Source of the article : Wikipedia
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