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Maksutov–Cassegrain Telescope
The Maksutov (also called a "Mak") is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the telescope (commonly called a "corrector plate" or " meniscus corrector shell"). The design corrects the problems of off-axis aberrations such as coma found in reflecting telescopes while also correcting chromatic aberration. It was patented in 1941 by Russian optician Dmitri Dmitrievich Maksutov. Maksutov based his design on the idea behind the Schmidt camera of using the spherical errors of a negative lens to correct the opposite errors in a spherical primary mirror. The design is most commonly seen in a Cassegrain variation, with an integrated secondary, that can use all-spherical elements, thereby simplifying fabrication. Maksutov telescopes have been sold on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maksutov 150mm
Maksutov may refer to: * Maksutov telescope, a catadioptric telescope with a meniscus corrector . * Dmitry Dmitrievich Maksutov (1896–1964), Russian optical engineer, inventor of the Maksutov telescope * Maksutov (crater), a lunar crater named after Dmitry Dmitrievich Maksutov * 2568 Maksutov, a main-belt asteroid named after Dmitry Dmitrievich Maksutov See also * Maksutov (surname) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Searchlight
A searchlight (or spotlight) is an apparatus that combines an extremely bright source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direction. It is usually constructed so that it can be swiveled about. Military use The first use of searchlights using carbon arc technology occurred during the Siege of Paris during the Franco-Prussian War. The Royal Navy used searchlights in 1882 to dazzle and prevent Egyptian forces from manning artillery batteries at Alexandria. Later that same year, the French and British forces landed troops under searchlights. By 1907 the value of searchlights had become widely recognized. One recent use was to assist attacks by torpedo boats by dazzling gun crews on the ships being attacked. Other uses included detecting enemy ships at greater distances, as signaling devices, and to assist landing parties. Searchlights were also used by battles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Telescope Making
''Amateur Telescope Making'' (''ATM'') is a series of three books edited by Albert G. Ingalls between 1926 and 1953 while he was an associate editor at ''Scientific American''. The books cover various aspects of telescope construction and observational technique, sometimes at quite an advanced level, but always in a way that is accessible to the intelligent amateur. The caliber of the contributions is uniformly high and the books have remained in constant use by both amateurs and professionals. The first volume was essentially a reprinting of articles written by Ingalls and Russell W. Porter for Ingalls's monthly column "The Backyard Astronomer" (later " The Amateur Scientist") in the 1920s. It also featured numerous drawings by Porter. The two later volumes contained chapters written by James Gilbert Baker, George Ellery Hale, George Willis Ritchey and others on topics ranging from lens grinding to monochromators to photoelectric photometry. Much of the information, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John F
John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second Epistle of John, often shortened to 2 John * Third Epistle of John, often shortened to 3 John People * John the Baptist (died c. AD 30), regarded as a prophet and the forerunner of Jesus Christ * John the Apostle (lived c. AD 30), one of the twelve apostles of Jesus * John the Evangelist, assigned author of the Fourth Gospel, once identified with the Apostle * John of Patmos, also known as John the Divine or John the Revelator, the author of the Book of Revelation, once identified with the Apostle * John the Presbyter, a figure either identified with or distinguished from the Apostle, the Evangelist and John of Patmos Other people with the given name Religious figures * John, father of Andrew the Apostle and Saint Peter * Pope Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PerkinElmer
PerkinElmer, Inc., previously styled Perkin-Elmer, is an American global corporation focused in the business areas of diagnostics, life science research, food, environmental and industrial testing. Its capabilities include detection, imaging, informatics, and service. PerkinElmer produces analytical instruments, genetic testing and diagnostic tools, medical imaging components, software, instruments, and consumables for multiple end markets. PerkinElmer is part of the S&P 500 Index and operates in 190 countries. History Founding Richard Perkin was attending the Pratt Institute in Brooklyn to study chemical engineering, but left after a year to try his hand on Wall Street. Still interested in the sciences, he gave public lectures on various topics. Charles Elmer ran a firm that supplied court reporters and was nearing retirement when he attended one of Perkin's lectures on astronomy being held at the Brooklyn Institute of Arts and Sciences. The two struck up a friendship ove ... [...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] |
Maksutov Spot Cassegrain
Maksutov may refer to: * Maksutov telescope, a catadioptric telescope with a meniscus corrector . * Dmitry Dmitrievich Maksutov (1896–1964), Russian optical engineer, inventor of the Maksutov telescope * Maksutov (crater) Maksutov is a crater on the far side of the Moon. It is located just to the south-southwest of the larger walled plain Oppenheimer. To the southwest lies the crater Nishina, and to the west-northwest is the merged crater pairing of Davisson and ..., a lunar crater named after Dmitry Dmitrievich Maksutov * 2568 Maksutov, a main-belt asteroid named after Dmitry Dmitrievich Maksutov See also * Maksutov (surname) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Mirror
A secondary mirror (or secondary) is the second deflecting or focusing mirror element in a reflecting telescope. Light gathered by the primary mirror is directed towards a focal point typically past the location of the secondary. Secondary mirrors in the form of an optically flat ''diagonal mirror'' are used to re-direct the light path in designs such as Newtonian reflectors. They are also used to re-direct and extend the light path and modify the final image in designs such as Cassegrain reflectors. The secondary is typically suspended by X-shaped struts (sometimes called a "spider") in the path of light between the source and the primary, but can be mounted on other types of mounts or optical elements such as optical windows, or schmidt and meniscus corrector plates. Employing secondary mirrors in optical systems causes some image distortion due to the obstruction of the secondary itself, and distortion from the spider mounts, commonly seen as cross-shaped diffraction spikes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newtonian Telescope
The Newtonian telescope, also called the Newtonian reflector or just a Newtonian, is a type of reflecting telescope invented by the English scientist Sir Isaac Newton, using a concave primary mirror and a flat diagonal secondary mirror. Newton's first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope. The Newtonian telescope's simple design has made it very popular with amateur telescope makers. Description 
A Newtonian telescope is composed of a primary mirror or objective, usually parabolic in shape, and a smaller mirror called the "secondary" which is flat. ...
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Journal Of The Optical Society Of America
The ''Journal of the Optical Society of America'' is a peer-reviewed scientific journal of optics, published by Optica. It was established in 1917 and in 1984 was split into two parts, A and B. ''Journal of the Optical Society of America A'' Part A covers various topics in optics, vision, and image science. The editor-in-chief is Olga Korotkova (University of Miami, USA). ''Journal of the Optical Society of America B'' Part B covers various topics in the field of optical physics, such as guided waves, laser spectroscopy, nonlinear optics, quantum optics, lasers, organic and polymer materials for optics, and ultrafast phenomena In optics, an ultrashort pulse, also known as an ultrafast event, is an electromagnetic pulse whose time duration is of the order of a picosecond (10−12 second) or less. Such pulses have a broadband optical spectrum, and can be created by .... The editor-in-chief is Kurt Busch ( Humboldt University of Berlin, Germany). References {{reflist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dennis Gabor
Dennis Gabor ( ; hu, Gábor Dénes, ; 5 June 1900 – 9 February 1979) was a Hungarian-British electrical engineer and physicist, most notable for inventing holography, for which he later received the 1971 Nobel Prize in Physics. He obtained British citizenship in 1934, and spent most of his life in England. Life and career Gabor was born as Günszberg Dénes, into a Jewish family in Budapest, Hungary. In 1918, his family converted to Lutheranism. Dennis was the first-born son of Günszberg Bernát and Jakobovits Adél. Despite having a religious background, religion played a minor role in his later life and he considered himself agnostic. In 1902, the family received permission to change their surname from Günszberg to Gábor. He served with the Hungarian artillery in northern Italy during World War I. He began his studies in engineering at the Technical University of Budapest in 1918, later in Germany, at the Charlottenburg Technical University in Berlin, now known as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Bouwers
Albert A. Bouwers (1893–1972) was a Dutch optical engineer.Ian Ridpath, "Bouwers telescope", ''A Dictionary of Astronomy'', 199first sentence of article/ref> He is known for developing and working with X-rays and various optical technologies as a high-level researcher at Philips research labs. He is lesser known for patenting in 1941 a catadioptric meniscus telescope design similar to but slightly predating the Maksutov telescope. Biography Bouwers was born in the town of Dalen in the Netherlands in 1893.Reflecting Telescope Optics, by Ray N. Wilson, page 498Google Books, pg 498/ref> He obtained his Ph.D. from Utrecht University in 1924, with a dissertation entitled in Dutch ''Over het meten der intensiteit van Röntgenstralen''. He was also the director of the Philips Laboratory's X-ray department. Bouwers developed a night vision device for viewing in low light conditions, called the "night eye". Albert Bouwers built a prototype for a design for a wide field concentric meniscus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
