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Microdot Camera Markiv
A microdot is text or an image substantially reduced in size to prevent detection by unintended recipients. Microdots are normally circular and around in diameter but can be made into different shapes and sizes and made from various materials such as polyester or metal. The name comes from microdots often having been about the size and shape of a typography, typographical dot, such as a full stop, period or the tittle of a lowercase ''i'' or ''j''. Microdots are, fundamentally, a steganography, steganographic approach to message protection. History In 1870 during the Franco-Prussian War, Paris was under siege and messages were sent by carrier pigeon. Parisian photographer René Dagron used microfilm to permit each pigeon to carry a high volume of messages, as pigeons can carry little weight. Improvement in technology since then has made even smaller miniaturization possible. At the 1925 International Congress of Photography in Paris, Emanuel Goldberg presented a method of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
German Microdots World War II Mexico Spain
German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also German nationality law **Germanic peoples (Roman era) *German diaspora * German language * German cuisine, traditional foods of Germany People * German (given name) * German (surname) * Germán, a Spanish name Places * German (parish), Isle of Man * German, Albania, or Gërmej * German, Bulgaria * German, Iran * German, North Macedonia * German, New York, U.S. * Agios Germanos, Greece Other uses * German (mythology), a South Slavic mythological being * Germans (band), a Canadian rock band * German (song), "German" (song), a 2019 song by No Money Enterprise * ''The German'', a 2008 short film * "The Germans", an episode of ''Fawlty Towers'' * ''The German'', a nickname for Congolese rebel André Kisase Ngandu See also * Germanic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interwar Period
In the history of the 20th century, the interwar period, also known as the interbellum (), lasted from 11 November 1918 to 1 September 1939 (20 years, 9 months, 21 days) – from the end of World War I (WWI) to the beginning of World War II (WWII). It was relatively short, yet featured many social, political, military, and economic changes throughout the world. Petroleum-based energy production and associated mechanisation led to the prosperous Roaring Twenties, a time of social mobility, social and economic mobility for the middle class. Automobiles, electric lighting, radio, and more became common among populations in the developed world, first world. The era's indulgences were followed by the Great Depression, an unprecedented worldwide economic downturn that severely damaged many of the world's largest economies. Politically, the era coincided with the rise of communism, starting in Russia with the October Revolution and Russian Civil War, at the end of WWI, and ended with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photolithography
Photolithography (also known as optical lithography) is a process used in the manufacturing of integrated circuits. It involves using light to transfer a pattern onto a substrate, typically a silicon wafer. The process begins with a photosensitive material, called a photoresist, being applied to the substrate. A photomask that contains the desired pattern is then placed over the photoresist. Light is shone through the photomask, exposing the photoresist in certain areas. The exposed areas undergo a chemical change, making them either soluble or insoluble in a developer solution. After development, the pattern is transferred onto the substrate through etching, chemical vapor deposition, or ion implantation processes. Ultraviolet, Ultraviolet (UV) light is typically used. Photolithography processes can be classified according to the type of light used, including ultraviolet lithography, deep ultraviolet lithography, extreme ultraviolet lithography, extreme ultraviolet lithography ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Frontier Foundation
The Electronic Frontier Foundation (EFF) is an American international non-profit digital rights group based in San Francisco, California. It was founded in 1990 to promote Internet civil liberties. It provides funds for legal defense in court, presents ''amicus curiae'' briefs, defends individuals and new Technology, technologies from what it considers abusive legal threats, works to expose government malfeasance, provides guidance to the government and courts, organizes political action and mass mailings, supports some new technologies which it believes preserve Liberty, personal freedoms and online civil liberties, maintains a database and web sites of related news and information, monitors and challenges potential legislation that it believes would infringe on Liberty, personal liberties and fair use, and solicits a list of what it considers are Patent misuse, abusive patents with intentions to defeat those that it considers are without merit (law), merit. History Foundat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellow Dots
Printer tracking dots, also known as printer steganography, DocuColor tracking dots, yellow dots, secret dots, or a machine identification code (MIC), is a digital watermark which many color laser printers and photocopiers produce on every printed page that identifies the specific device that was used to print the document. Developed by Xerox and Canon in the mid-1980s, the existence of these tracking codes became public only in 2004. History In the mid-1980s, Xerox pioneered an encoding mechanism for a unique number represented by tiny dots spread over the entire print area, and first deployed this scheme in its DocuColor line of printers. Xerox developed this surreptitious tracking code "to assuage fears that their color copiers could be used to counterfeit bills" and received U.S. Patent No. 5515451 describing the use of the yellow dots to identify the source of a copied or printed document. The scheme was then widely deployed in other printers, including those made by other m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serial Number
A serial number (SN) is a unique identifier used to ''uniquely'' identify an item, and is usually assigned incrementally or sequentially. Despite being called serial "numbers", they do not need to be strictly numerical and may contain letters and other typographical symbols, or may consist entirely of a character (computing), character string (computer science), string. Applications of serial numbering Serial numbers identify otherwise identical individual units, thereby serving various practical uses. Serial numbers are a deterrent against theft and counterfeit products, as they can be recorded, and stolen or otherwise irregular goods can be identified. Banknotes and other transferable documents of value bear serial numbers to assist in preventing counterfeiting and tracing stolen ones. They are valuable in quality control, as once a defect is found in the production of a particular batch of product, the serial number will identify which units are affected. Some items with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etching
Etching is traditionally the process of using strong acid or mordant to cut into the unprotected parts of a metal surface to create a design in intaglio (incised) in the metal. In modern manufacturing, other chemicals may be used on other types of material. As a method of printmaking, it is, along with engraving, the most important technique for old master prints, and remains in wide use today. In a number of modern variants such as microfabrication etching and photochemical milling, it is a crucial technique in modern technology, including circuit boards. In traditional pure etching, a metal plate (usually of copper, zinc or steel) is covered with a waxy ground which is resistant to acid. The artist then scratches off the ground with a pointed etching needle where the artist wants a line to appear in the finished piece, exposing the bare metal. The échoppe, a tool with a slanted oval section, is also used for "swelling" lines. The plate is then dipped in a bath of aci ... [...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] |
Minox
Minox (pronounced ) is a manufacturer of cameras, known especially for its subminiature camera. The first product to carry the Minox name was a subminiature camera, conceived in 1922, and finally produced in 1936, by Baltic German Walter Zapp. The Latvian factory VEF () manufactured the camera from 1937 to 1943. After World War II, the camera was redesigned and production resumed in Germany in 1948. Zapp originally envisioned the Minox to be a camera for everyone requiring only little photographic knowledge. Yet in part due to its high manufacturing costs, the Minox became more well known as a must-have luxury item. From the start the Minox also gained wide notoriety as a espionage, spy camera. Minox branched out into #Minox 35 mm cameras, 35 mm film format and #Other products, 110 film format cameras in 1974 and 1976, respectively. Minox continues to operate today, producing or branding optical and photographic equipment. History From 1936 to 1975, the history of the Minox b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Zapp
Walter Zapp (; – 17 July 2003) was a Baltic Germans, Baltic German inventor. His best-known creation was the Minox subminiature photography, subminiature camera. Over the course of his life, he was granted over 60 patents. Biography Zapp was born in Riga, Governorate of Livonia (now Latvia) to a Baltic German mother and a British father. In 1932, while living in Estonia, he began developing the then subminiature camera by first creating wooden models, which led to the first prototype in 1936. It was introduced to the market in 1938. Minox cameras were made by VEF (Valsts Elektrotehniskā Fabrika) in Latvia. VEF made 17,000 Minox cameras. During the Baltic Germans#Spring 1941 resettlement, Spring 1941 Resettlement of Baltic Germans, Zapp moved to Nazi Germany, Germany. From 1941 to 1945, he worked on the development of electron microscopy at AEG (German company), AEG in Berlin. After World War II, in 1945, he founded the Minox, Minox GmbH in Wetzlar, Germany. The co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Halide
A silver halide (or silver salt) is one of the chemical compounds that can form between the Chemical element, element silver (Ag) and one of the halogens. In particular, bromine (Br), chlorine (Cl), iodine (I) and fluorine (F) may each combine with silver to produce silver bromide (AgBr), silver chloride (AgCl), silver iodide (AgI), and four forms of silver fluoride, respectively. As a group, they are often referred to as the silver halides, and are often given the pseudo-chemical notation AgX. Although most silver halides involve silver atoms with oxidation states of +1 (Ag+), silver halides in which the silver atoms have oxidation states of +2 (Ag2+) are known, of which silver(II) fluoride is the only known stable one. Silver halides are light-sensitive chemicals, and are commonly used in photographic film and paper. Applications Light sensitivity Silver halides are used in photographic film and photographic paper, including graphic art film and paper, where silver halide cry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, aniline is "electron-rich". It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
