|
Ernst Ruhmer
Ernst Walter Ruhmer (15 April 1878 – 8 April 1913) was a German physicist. He was best known for investigating practical applications making use of the light-sensitivity properties of selenium, which he employed in developing wireless telephony using line-of-sight optical transmissions, sound-on-film audio recording, and television transmissions over wires. Career Ruhmer's father was an inventor and manufacturer. From 1897 to 1900 he studied mathematics and natural sciences in Berlin, and the next year continued his studies in Giessen. His early work included extensive research in developing selenium cells that were more sensitive, and faster reacting, to the effects of light illumination. In December 1902 he and Salomon Kalischer were issued German patent 151,971 for their method of producing photographic images by exposing electrically conductive selenium-coated plates. Ruhmer also designed a light-sensitive control switch, using a selenium cell, which was successfully used to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenium
Selenium is a chemical element; it has symbol (chemistry), symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elemental state or as pure ore compounds in Earth's crust. Selenium ( ) was discovered in 1817 by , who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in :Sulfide minerals, metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores. Minerals that are pure selenide or selenate compounds are rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been mostly replaced with silicon semiconductor devices. Selenium is still used in a few types of Direct current, DC power surge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Current
Carrier current transmission, originally called wired wireless, employs guided low-power Radio frequency, radio-frequency signals, which are transmitted along electrical conductors. The transmissions are picked up by receivers that are either connected to the conductors, or a short distance from them. Carrier current transmission is used to send audio and telemetry to selected locations, and also for low-power broadcasting that covers a small geographical area, such as a college campus. The most common form of carrier current uses longwave or medium wave Amplitude modulation, AM radio signals that are sent through existing electrical wiring, although other conductors can be used, such as telephone lines. Technology Carrier current generally uses low-power transmissions. In cases where the signals are being carried over electrical wires, special preparations must be made for distant transmissions, as the signals cannot pass through standard utility transformers. Signals can bridge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1913 Deaths
Events January * January – Joseph Stalin travels to Vienna to research his ''Marxism and the National Question''. This means that, during this month, Stalin, Hitler, Trotsky and Tito are all living in the city. * January 3 – First Balkan War: Greece completes its Battle of Chios (1912), capture of the eastern Aegean island of Chios, as the last Ottoman forces on the island surrender. * January 13 – Edward Carson founds the (first) Ulster Volunteers, Ulster Volunteer Force, by unifying several existing Ulster loyalism, loyalist militias to resist home rule for Ireland. * January 18 – First Balkan War: Battle of Lemnos (1913), Battle of Lemnos – Greek admiral Pavlos Kountouriotis forces the Turkish fleet to retreat to its base within the Dardanelles, from which it will not venture for the rest of the war. * January 23 – 1913 Ottoman coup d'état: Enver Pasha comes to power. February * February 1 – New York City's Grand Central Te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1878 Births
Events January * January 5 – Russo-Turkish War: Battle of Shipka Pass IV – Russian and Bulgarian forces defeat the Ottoman Empire. * January 9 – Umberto I becomes King of Italy. * January 17 – Russo-Turkish War: Battle of Philippopolis – Russian troops defeat the Ottoman Empire. * January 23 – Benjamin Disraeli orders the British fleet to the Dardanelles. * January 24 – Russian revolutionary Vera Zasulich shoots at Fyodor Trepov, Governor of Saint Petersburg. * January 28 – In the United States: ** The world's First Telephone Exchange begins commercial operation in New Haven, Connecticut. ** '' The Yale News'' becomes the first daily college newspaper in the U.S. * January 31 – Turkey agrees to an armistice at Adrianople. February * February 2 – Greece declares war on the Ottoman Empire. * February 7 – Pope Pius IX dies, after a 31½ year pontificate (the longest definitely confirmed). * February 8 & ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathode Ray Tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms on an oscilloscope, a Film frame, frame of video on an Analog television, analog television set (TV), Digital imaging, digital raster graphics on a computer monitor, or other phenomena like radar targets. A CRT in a TV is commonly called a picture tube. CRTs have also been Williams tube, used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT TVs and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster scan, raster. In color devices, an image is produced by con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brussels International 1910
The Brussels International Exposition (; ) of 1910 was a world's fair held in Brussels, Belgium, from 23 April to 1 November 1910. This was just thirteen years after Brussels' previous world's fair. It received 13 million visitors, covered and lost 100,000 Belgian francs. Location The grounds and buildings were partly located around the ''Solbosch'' district (in the City of Brussels' southern extension), and partly in the Parc du Cinquantenaire/Jubelpark (a remainder of the 1897 World's Fair), where the fine art's exhibition took place. The colonial exhibition was hosted in the newly built Palace of the Colonies, today's Royal Museum for Central Africa, in the suburb of Tervuren. Another major site for the exhibition was the Mont des Arts/Kunstberg in central Brussels, although this site was largely demolished during the post-war construction process of Brusselisation. File:Algemeens Wereldtentoonstelling van Brussel 1910 - Koloniale Afdeeling Park van Tervueren (imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palais De Justice, Brussels
Palais () may refer to: * Dance hall, popularly a ''palais de danse'', in the 1950s and 1960s in the UK * ''Palais'', French for palace **Grand Palais, the Grand Palais des Champs-Elysées ** Petit Palais, an art museum in Paris * Palais River in the French ''département'' of Deux-Sèvres * Palais Theatre, historic cinema ("picture palace") in Melbourne, Australia * Richard Palais (born 1931), American mathematician * Le Palais, a commune in Morbihan departement, France See also * Palais Royal (other) * Palai (other) * Palace (other) A palace is a grand residence, usually for royalty or other high-ranking dignitaries. Palace may also refer to: Places * Palace (ward), a former electoral ward of Hammersmith and Fulham London Borough Council that existed from 1978 to 2002 * Pal ... * Palas (other) {{disambig, surname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Ruhmer Demonstrating Simple Television System (1909)
Ernst is both a surname and a given name, the German, Dutch, and Scandinavian form of Ernest. Notable people with the name include: Surname * Adolf Ernst (1832–1899) German botanist known by the author abbreviation "Ernst" * Anton Ernst (born 1975), South African film producer * Alice Henson Ernst (1880-1980), American writer and historian * Bastian Ernst (born 1987), German politician * Britta Ernst (born 1961), German politician * Cornelia Ernst (born 1956), German politician * Edzard Ernst (born 1948), German-British academic * Emil Ernst (1889–1942), astronomer * Ernie Ernst (1924/25–2013), American judge * Eugen Ernst (1864–1954), German politician * Fabian Ernst (born 1979), German soccer player * Fedir Ernst (1891-1942), Ukrainian art historian * Gustav Ernst (born 1944), Austrian writer * Heinrich Wilhelm Ernst (1812–1865), Moravian violinist and composer * Jim Ernst (born 1942), Canadian politician * Jimmy Ernst (1920–1984), American painter, son of Max Er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Film
A sound film is a Film, motion picture with synchronization, synchronized sound, or sound technologically coupled to image, as opposed to a silent film. The first known public exhibition of projected sound films took place in Paris in 1900, but decades passed before sound motion pictures became commercially practical. Reliable synchronization was difficult to achieve with the early sound-on-disc systems, and amplification and recording quality were also inadequate. Innovations in sound-on-film led to the first commercial screening of Short film, short motion pictures using the technology, which took place in 1923. Before sound-on-film technology became viable, soundtracks for films were commonly played live with organs or pianos. The primary steps in the commercialization of sound cinema were taken in the mid-to-late 1920s. At first, the sound films which included synchronized dialogue, known as "talking pictures", or "talkies", were exclusively shorts. The earliest feature fil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographophone
A photographophone is a device, first developed by Ernst Ruhmer of Berlin, Germany in 1900, used to produce and play back audio recordings. Photographophone recording uses celluloid film. The process is started by speaking into a microphone, connected to a battery pack, whose modulated electrical output produces corresponding variations in the light of an arc (later an incandescent lamp An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a filament until it glows. The filament is enclosed in a glass bulb that is eith ...) that passes through a cylindrical lens slot, which creates lines on the moving sensitive film. This film, after being taken out of the box and developed, shows a series of perpendicular striations parallel to one another, which are a photographic record of the sound waves created by the telephone transmitter output. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Robert Erskine-Murray
Dr James Robert Erskine-Murray FRSE MIEE (1868-1927) was a Scottish electrical engineer and inventor. A protege of Lord Kelvin, he also worked with Marconi and was a pioneer in the development of the telegraph. He wrote extensively on telegraphy and wireless communication. Early life He was born in Edinburgh on 24 October 1868, the eldest son of Alexander Erskine Erskine-Murray , Sheriff of Glasgow (1832-1907), and his wife, Helen Pringle, daughter of Robert Pringle of Symington. In 1886 he began study under Lord Kelvin at Glasgow University assisting Kelvin in electrical experiments from 1888 and graduating BSc in 1892. Career He began lecturing in electricity at Heriot-Watt University, Heriot-Watt College in Edinburgh in 1896. In 1897 he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Lord Kelvin, John Gray McKendrick, William Jack (mathematician), William Jack and Joseph Bell. He received a doctorate (DSc) in 1897 and in 1898 he became personal as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
