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Rangefinding Telemeter
A rangefinder (also rangefinding telemeter, depending on the context) is a device used to Length measurement, measure distances to remote objects. Originally optical devices used in surveying, they soon found applications in other fields, such as photography, the military, and space travel. They were especially useful for finding the range of a target, such as in naval gunnery and anti-aircraft artillery. The word ''telemeter'' is derived . Designs The first rangefinder telemeter was invented by James Watt in 1769 and put to use in 1771 in surveying canals. Watt called his instrument a micrometer, a term now used with a different meaning in engineering (the micrometer screw gauge). It consisted of two parallel reticle, hairs in the focal plane of a telescope eyepiece crossing an upright hair. At the point to be measured, two sliding targets on a surveyor's rod were adjusted to align with the hairs in the telescope. The distance to the rod could then be determined from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bundesarchiv Bild 183-J08361, Entfernungsmesser Einer Vierlings-Flak
The German Federal Archives or Bundesarchiv (BArch) (, lit. "Federal Archive") are the national archives of Germany. They were established at the current location in Koblenz in 1952. They are subordinated to the Federal Commissioner for Culture and the Media (Claudia Roth since 2021) under the German Chancellery, and before 1998, to the Federal Ministry of the Interior (Germany), Federal Ministry of the Interior. On 6 December 2008, the Archives donated 100,000 photos to the public, by making them accessible via Wikimedia Commons. History The federal archive for institutions and authorities in Germany, the first precursor to the present-day Federal Archives, was established in Potsdam, Brandenburg in 1919, a later date than in other European countries. This national archive documented German government dating from the founding of the North German Confederation in 1867. It also included material from the older German Confederation and the Imperial Chamber Court. The oldest docum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jesse Ramsden
Jesse Ramsden Fellow of the Royal Society, FRS FRSE (6 October 1735 – 5 November 1800) was a British mathematician, astronomy, astronomical and scientific instrument maker. His reputation was built on the engraving and design of dividing engines which allowed high accuracy measurements of angles and lengths in instruments. He produced instruments for astronomy that were especially well known for maritime use where they were needed for the measurement of latitudes and for his surveying instruments which were widely used for cartography and land survey both across the British Empire and outside. An achromatic eyepiece that he invented for telescopes and microscopes continues to be known as the Ramsden eyepiece. Life Ramsden was born at Salterhebble, Halifax, West Yorkshire, Halifax, West Riding of Yorkshire, England the son of Thomas Ramsden, an innkeeper and his wife Abigail née Flather. Having attended the free school at Halifax from 1744 to 1747, he was sent at the age of twe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photography
Photography is the visual arts, art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication. A person who operates a camera to capture or take Photograph, photographs is called a photographer, while the captured image, also known as a photograph, is the result produced by the camera. Typically, a lens is used to focus (optics), focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed Exposure (photography), exposure. With an electronic image sensor, this produces an Charge-coupled device, electrical charge at each pixel, which is Image processing, electro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the motion, movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, marine navigation, air navigation, aeronautic navigation, and space navigation. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks. All navigational techniques involve locating the navigator's Position (geometry), position compared to known locations or patterns. Navigation, in a broader sense, can refer to any skill or study that involves the determination of position and Relative direction, direction. In this sense, navigation includes orienteering and pedestrian navigation. For marine navigation, this involves the safe movement of ships, boats and other nautical craft either on or underneath the water using positions from navigation equipment with appropriate nautical char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is coherence (physics), ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and Photolithography#Light sources, lithography. It also allows a laser beam to stay narrow over great distances (collimated light, collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skinny Triangle
In trigonometry, a skinny triangle is a triangle whose height is much greater than its base. The solution of such triangles can be greatly simplified by using the approximation that the sine of a small angle is equal to that angle in radians. The solution is particularly simple for skinny triangles that are also isosceles or right triangles: in these cases the need for trigonometric functions or tables can be entirely dispensed with. The skinny triangle finds uses in surveying, astronomy, and shooting. Isosceles triangle The approximated solution to the skinny isosceles triangle, referring to figure 1, is: :b \approx r \theta \, :\text \approx \frac \theta r^2 \, This is based on the small-angle approximations: :\sin\theta \approx \theta, \quad \theta \ll 1 \, and :\cos\theta = \sin\left(\frac-\theta \right) \approx 1, \quad \theta \ll 1 when \scriptstyle \theta is in radians. The proof of the skinny triangle solution follows from the small-angle approximation by appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereoscopic Rangefinder
A stereoscopic rangefinder or stereoscopic telemeter is an optical device that measures distance from the observer to a target, using the observer's capability of binocular vision. It looks similar to a coincidence rangefinder, which uses different principles and has only one eyepiece. German instruments tended to use the stereoscopic principle while British ones used coincidence. Technical principle A stereoscopic rangefinder uses two eyepieces and relies on the operator's visual cortex to merge the two images into a single picture. A reference mark is separately inserted into each eyepiece. The operator first adjusts the direction of the range finder so that the fixed mark is centered on the target, and then the prisms are rotated until the mark appears to overlap in the operator's combined view. The range to the target is proportional to the degree of rotation of the prisms.FM 4-15, Coast Artillery Field ManualSeacoast Artillery Fire Control and Position Finding U.S. Governmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Zeiss AG
Zeiss ( ; ) is a German manufacturer of optical systems and optoelectronics, founded in Jena, Germany, in 1846 by optician Carl Zeiss. Together with Ernst Abbe (joined 1866) and Otto Schott (joined 1884) he laid the foundation for today's multinational company. The current company emerged from a reunification of Carl Zeiss companies in East and West Germany with a consolidation phase in the 1990s. ZEISS is active in four business segments with approximately equal revenue (Industrial Quality and Research, Medical Technology, Consumer Markets and Semiconductor Manufacturing Technology) in almost 50 countries, has 30 production sites and around 25 development sites worldwide. Carl Zeiss AG is the holding of all subsidiaries within Zeiss Group, of which Carl Zeiss Meditec AG is the only one that is traded at the stock market. Carl Zeiss AG is owned by the foundation Carl-Zeiss-Stiftung. The Zeiss Group has its headquarters in southern Germany, in the small town of Oberkochen, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Pulfrich
Carl P. Pulfrich (September 24, 1858 in Burscheid, Rhine Province, Kingdom of Prussia – August 12, 1927 in Baltic Sea, drowned when his canoe capsized) was a German physicist, noted for advancements in optics made as a researcher for the Carl Zeiss company in Jena around 1880, and for documenting the Pulfrich effect, a psycho-optical phenomenon that can be used to create a type of 3-D visual effect. Carl Pulfrich was the brother-in-law of Heinrich Hertz. Advances in optics Pulfrich was employed to develop stereoscopy from being pure entertainment to a powerful quantitative technique. His apparatus to measure distances stereoscopically was first presented in Munich in 1899. This was further developed to a stereo-comparator which was presented in Hamburg in 1901. Stereoscopy was used for topographic mapping, astronomy and oceanography because everything could be done quickly and precisely. He pioneered the use of aerial photography surveys. He introduced in 1909 a "Va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coastal Artillery
Coastal artillery is the branch of the armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications. From the Middle Ages until World War II, coastal artillery and naval artillery in the form of cannons were highly important to military affairs and generally represented the areas of highest technology and capital cost among materiel. The advent of 20th-century technologies, especially military aviation, naval aviation, jet aircraft, and guided missiles, reduced the primacy of cannons, battleships, and coastal artillery. In countries where coastal artillery has not been disbanded, these forces have acquired amphibious capabilities. In littoral warfare, mobile coastal artillery armed with surface-to-surface missiles can still be used to deny the use of sea lanes. It was long held as a rule of thumb that one shore-based gun equaled three naval guns of the same caliber, due to the steadiness of the coastal gun which allowed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
