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Serrurier Truss
A Serrurier truss is used in telescope tube assembly construction. The design was created in 1935 by engineer Mark U. Serrurier when he was working on the Mount Palomar Hale telescope.Encyclopedia of Astronomy and Physics, "Reflecting Telescopes", Paul Murdin and Patrick Moore The design solves the problem of truss flexing by supporting the primary objective mirror and the secondary mirror by two sets of opposing trusses before and after the declination pivot. The trusses are designed to have an equal amount of flexure, which allows the optics to stay on a common optical axis. When flexing, the "top" truss resists tension and the "bottom" truss resists compression. This has the effect of keeping the optical elements parallel to each other. The net result is all of the optical elements stay in collimation regardless of the orientation of the telescope. Some Serrurier truss designs end the truss members with a short flexible rod creating a more ideal "parallel motion flexure" syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Truss
A truss is an assembly of ''members'' such as beams, connected by ''nodes'', that creates a rigid structure. In engineering, a truss is a structure that "consists of two-force members only, where the members are organized so that the assemblage as a whole behaves as a single object". A "two-force member" is a structural component where force is applied to only two points. Although this rigorous definition allows the members to have any shape connected in any stable configuration, trusses typically comprise five or more triangular units constructed with straight members whose ends are connected at joints referred to as ''nodes''. In this typical context, external forces and reactions to those forces are considered to act only at the nodes and result in forces in the members that are either tensile or compressive. For straight members, moments (torques) are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes, as is necessary for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collimated Light
A collimated beam of light or other electromagnetic radiation has parallel rays, and therefore will spread minimally as it propagates. A perfectly collimated light beam, with no divergence, would not disperse with distance. However, diffraction prevents the creation of any such beam. Light can be approximately collimated by a number of processes, for instance by means of a collimator. Perfectly collimated light is sometimes said to be ''focused at infinity''. Thus, as the distance from a point source increases, the spherical wavefronts become flatter and closer to plane waves, which are perfectly collimated. Other forms of electromagnetic radiation can also be collimated. In radiology, X-rays are collimated to reduce the volume of the patient's tissue that is irradiated, and to remove stray photons that reduce the quality of the x-ray image ("film fog"). In scintigraphy, a gamma ray collimator is used in front of a detector to allow only photons perpendicular to the surface to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Telescope Components
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for by using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Telescope Parts And Construction
Hardware Accessories *Finderscope *Iron sight * Reflector (reflex) sight * Cheshire collimator: A simple tool to collimate a telescope Control *Clock drive *GoTo Mechanical construction *Mirror support cell *Serrurier truss *Silvering Mounts *Telescope mount - Types include: ** Altazimuth mount ** Equatorial mount *** Equatorial platform **** Poncet Platform *** Fork mount *** German equatorial mount *** Springfield mount Optics Mirrors and lenses are the critical light-bending components of a telescope. *Objective: The first lens or curved mirror that collects and focuses the incoming light. **Primary lens: The objective of a refracting telescope. **Primary mirror: The objective of a reflecting telescope. *Corrector plate: A full aperture negative lens placed before a primary mirror designed to correct the optical aberrations of the mirror. **Schmidt corrector plate: An aspheric-shaped corrector plate used in the Schmidt telescope. **Meniscus corrector: A meniscus-shaped cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicholas U
Nicholas is a male given name and a surname. The Eastern Orthodox Church, the Roman Catholic Church, and the Anglican Churches celebrate Saint Nicholas every year on December 6, which is the name day for "Nicholas". In Greece, the name and its derivatives are especially popular in maritime regions, as St. Nicholas is considered the protector saint of seafarers. Origins The name is derived from the Greek name Νικόλαος (''Nikolaos''), understood to mean 'victory of the people', being a compound of νίκη ''nikē'' 'victory' and λαός ''laos'' 'people'.. An ancient paretymology of the latter is that originates from λᾶς ''las'' ( contracted form of λᾶας ''laas'') meaning 'stone' or 'rock', as in Greek mythology, Deucalion and Pyrrha recreated the people after they had vanished in a catastrophic deluge, by throwing stones behind their shoulders while they kept marching on. The name became popular through Saint Nicholas, Bishop of Myra in Lycia, the inspir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dobsonian
A Dobsonian telescope is an altazimuth-mounted Newtonian telescope design popularized by John Dobson in 1965 and credited with vastly increasing the size of telescopes available to amateur astronomers. Dobson's telescopes featured a simplified mechanical design that was easy to manufacture from readily available components to create a large, portable, low-cost telescope. The design is optimized for observing faint, deep-sky objects such as nebulae and galaxies. This type of observation requires a large objective diameter (i.e. light-gathering power) of relatively short focal length and portability for travel to less light-polluted locations. Dobsonians are intended to be what is commonly called a "light bucket" operating at low magnification, and therefore the design omits features found in other amateur telescopes such as equatorial tracking. Dobsonians are popular in the amateur telescope making community, where the design was pioneered and continues to evolve. A number of c ... [...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] |
Compression (physical)
In mechanics, compression is the application of balanced inward ("pushing") forces to different points on a material or structure, that is, forces with no net sum or torque directed so as to reduce its size in one or more directions.Ferdinand Pierre Beer, Elwood Russell Johnston, John T. DeWolf (1992), "Mechanics of Materials". (Book) McGraw-Hill Professional, It is contrasted with tension or traction, the application of balanced outward ("pulling") forces; and with shearing forces, directed so as to displace layers of the material parallel to each other. The compressive strength of materials and structures is an important engineering consideration. In uniaxial compression, the forces are directed along one direction only, so that they act towards decreasing the object's length along that direction. The compressive forces may also be applied in multiple directions; for example inwards along the edges of a plate or all over the side surface of a cylinder, so as to reduce it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telescope
A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word ''telescope'' now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. Etymology The word ''telescope'' was coin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (physics)
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression (physics), compression. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newton (unit), newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Axis
An optical axis is a line along which there is some degree of rotational symmetry in an optical system such as a camera lens, microscope or telescopic sight. The optical axis is an imaginary line that defines the path along which light propagates through the system, up to first approximation. For a system composed of simple lenses and mirrors, the axis passes through the center of curvature of each surface, and coincides with the axis of rotational symmetry. The optical axis is often coincident with the system's mechanical axis, but not always, as in the case of off-axis optical systems. For an optical fiber, the optical axis is along the center of the fiber core, and is also known as the ''fiber axis''. See also * Ray (optics) * Cardinal point (optics) * Antenna boresight In telecommunications and radar engineering, antenna boresight is the axis of maximum gain (maximum radiated power) of a directional antenna. For most antennas the boresight is the axis of symmetry of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
