Principle of the periscope. The periscope on the left uses mirrors at location "a" whereas the right uses prisms at "b". The observer is "c".

A periscope is an instrument for observation from a concealed position. In its simplest form it is a tube in each end of which are mirrors set parallel to each other and at an angle of 45° with a line between them. Image File history File links Periscopes_simple. ... Image File history File links Periscopes_simple. ... A mirror, reflecting a vase. ...

A periscope may be used as a toy or for seeing over people's heads in a crowd. This form of periscope, with the addition of two simple lenses, was used for observation purposes in the trenches during World War I. Periscopes are also used in some gun turrets and armoured vehicles. A teddy bear A toy is an object meant to be played with. ... Combatants Allied Powers: Russian Empire France British Empire Italy United States Central Powers: Austria-Hungary German Empire Ottoman Empire Bulgaria Commanders Nicholas II Aleksei Brusilov Georges Clemenceau Joseph Joffre Ferdinand Foch Herbert Henry Asquith Douglas Haig John Jellicoe Victor Emmanuel III Luigi Cadorna Armando Diaz Woodrow Wilson John Pershing Franz... Turret (highlighted) attached to a tower on a baronial building in Scotland In architecture, a turret is a small tower that projects from the wall of a building, such as a medieval castle or baronial house. ... An armoured fighting vehicle (AFV) is a military vehicle, equipped with protection against hostile attacks and often mounted weapons. ...

More complex periscopes, using prisms instead of mirrors, and providing magnification, are used on submarines. The overall design of the classical submarine periscope is very simple: two telescopes pointed into each other. If the two telescopes have different individual magnification, the difference between them causes an overall magnification or reduction. If a shaft of light entering a prism is sufficiently small such that the coloured edges meet, a spectrum results In optics, a prism is a device used to refract light, reflect it or break it up (to disperse it) into its constituent spectral colours (colours of the rainbow). ... German UC-1 class World War I submarine A model of Günther Priens Unterseeboot 47 (U-47), German WWII Type VII diesel-electric hunter Typhoon class nuclear ballistic missile submarine USS Virginia, a Virginia-class nuclear attack (SSN) submarine A submarine is a specialized watercraft that can operate...

Early examples

Gundlach periscope.

Johann Gutenberg, better known for his contribution to printing technology, marketed a periscope in the 1430s to enable pilgrims to see over the heads of the crowd at the vigintennial religious festival at Aachen. Simon Lake used periscopes in his submarines in 1902. Sir Howard Grubb perfected it in World War I[1]. Morgan Robertson claims to have described a submarine using a periscope in his fictional works. Periscopes, in some cases fixed to rifles, were used in World War I to enable soldiers to see out of the trenches. Image File history File links Download high resolution version (382x1027, 77 KB)Gundlach Periscope used to look forward (upper panel) and backwards (lower panel). ... Image File history File links Download high resolution version (382x1027, 77 KB)Gundlach Periscope used to look forward (upper panel) and backwards (lower panel). ... This article or section is missing references or citation of sources. ... For other articles which might have the same name, see Print (disambiguation). ... Events and Trends A map of Europe in the 1430s. ... Oche redirects here; in darts the oche is the line from which players must throw. ... Simon Lake Simon Lake (September 4, 1866 - June 23, 1945) was an American mechanical engineer and naval architect who obtained over two hundred patents for advances in naval design and competed with John Holland to build the first submarines for the United States Navy. ... Sir Howard Grubb, FRS, (1844-1931) was a designer and maker of telescopes from Dublin. ... Morgan Robertson (September 30, 1861 - March 24, 1915) was a well-known American author of short stories and novels, and the inventor of the periscope. ... Combatants Allied Powers: Russian Empire France British Empire Italy United States Central Powers: Austria-Hungary German Empire Ottoman Empire Bulgaria Commanders Nicholas II Aleksei Brusilov Georges Clemenceau Joseph Joffre Ferdinand Foch Herbert Henry Asquith Douglas Haig John Jellicoe Victor Emmanuel III Luigi Cadorna Armando Diaz Woodrow Wilson John Pershing Franz...

Periscopes are extensively used in tanks, enabling drivers or tank's commanders to inspect the situation without leaving the safety of the tank. An important development was Gundlach's periscope allowing tank commander to obtain 360 degree view without moving the seats (pictured). The design was first used in the Polish 7-TP light tank. Shortly before the war it was given to the British and was used in most tanks of WWII, including the British Crusader, Churchill, Valentine, and Cromwell and the American Sherman. The design was later copied and used extensively in tanks of the USSR (including the T-34 and T-70) and Germany. Rudolf Gundlach (1894-1957) was a Polish engineer, tank constructor and inventor. ... General characteristics Length: 4. ... Combatants Allied Powers Axis Powers Casualties Military dead: 17,000,000 Civilian dead: 33,000,000 Total dead: 50,000,000 Military dead: 8,000,000 Civilian dead: 4,000,000 Total dead 12,000,000 World War II (abbreviated WWII), or the Second World War, was a worldwide conflict... One of the primary cruiser tanks of the United Kingdom during World War II, the Cruiser Tank VI Crusader was perhaps the most important British tank of the North African Campaign. ... The Infantry Tank IV Churchill was a heavy British infantry tank of the Second World War, best known for its heavy armour and its use as the basis of many specialist vehicles. ... The most numerous British manufactured tank of World War II, the Infantry Tank III Valentine was known mainly for its inexpensive cost and high reliability. ... The A27M Cruiser Tank VIII Cromwell, named after the English Civil War leader Oliver Cromwell, was one of the most successful series of cruiser tanks fielded by Britain in World War II. It was the first tank in the British arsenal to combine a dual-purpose gun, high speed, and... WWII foreign variants and use: Lend-Lease Sherman tanks Post-WWII foreign variants and use: Postwar Sherman tanks The Medium Tank M4 was the main tank designed and built by the United States for allied forces in World War II, totaling roughly 50,000 tanks plus thousands more derivative vehicles... The T-34 is a Soviet medium tank first produced in 1940. ... The T-70 was a light tank in the Red Army during the WW2. ...

Australian light horseman using a periscope rifle, Gallipoli 1915

Periscopes proved useful in trench warfare, as seen in the illustrations, representative of action at Gallipoli Image File history File links British_trench_periscope_Cape_Helles_1915. ... Image File history File links British_trench_periscope_Cape_Helles_1915. ... Download high resolution version (800x779, 106 KB)Australian sniper using a periscope rifle at Gallipoli, 1915. ... Download high resolution version (800x779, 106 KB)Australian sniper using a periscope rifle at Gallipoli, 1915. ... The Australian Light Horse in Palestine during World War I The Australian Light Horse soldiers were mounted infantry who served during the Second Boer War and World War I. The Light Horse differed from cavalry in that they usually fought dismounted, using their horses as transport to the battlefield and... Sgt. ... Trench warfare is a form of war in which both opposing armies have static lines of defense. ... Gallipoli peninsula (Turkish: , Greek: ) is located in Turkish Thrace, the European part of Turkey, with the Aegean Sea to the west and the Dardanelles straits to the east. ...

Naval use

Periscopes allow a submarine submerged at shallow depth to search for targets and threats in the surrounding sea and air. When not in use, the periscope is retracted into the hull. A sub commander in tactical conditions must exercise discretion when using his periscope, since it creates an observable wake and may be detectable to radar, giving away the sub's position.

Officer at periscope in control room of submarine

A simple, fixed naval periscope using plane mirrors was built by the Frenchman Marie Davey in 1854. Thomas H. Doughty of the US Navy later invented a prismatic version for use in the American Civil War (circa 1891). Image File history File linksMetadata Download high resolution version (1107x1387, 204 KB) Officer at periscope in control room of submarine [1] File links The following pages link to this file: Periscope Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize... Image File history File linksMetadata Download high resolution version (1107x1387, 204 KB) Officer at periscope in control room of submarine [1] File links The following pages link to this file: Periscope Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize... 1854 (MDCCCLIV) was a common year starting on Sunday (see link for calendar). ... Combatants United States of America (Union) Confederate States of America (Confederacy) Commanders Abraham Lincoln, Ulysses S. Grant Jefferson Davis, Robert E. Lee Strength 2,200,000 1,064,000 Casualties 110,000 killed in action, 360,000 total dead, 275,200 wounded 93,000 killed in action, 258,000 total...

The invention of the collapsible periscope for use in submarine warfare is usually credited to Simon Lake in 1902, who called his device the omniscope or skalomniscope. There is also a report that an Italian, Triulzi, demonstrated such a device in 1901 calling it a cleptoscope. Simon Lake Simon Lake (September 4, 1866 - June 23, 1945) was an American mechanical engineer and naval architect who obtained over two hundred patents for advances in naval design and competed with John Holland to build the first submarines for the United States Navy. ... 1902 (MCMII) was a common year starting on Wednesday (see link for calendar). ... 1901 (MCMI) was a common year starting on Tuesday (see link for calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ...

Another early example of naval use of the periscope are the two adapted on the experimental French submarine Gymnote by the Captain Arthur Krebs in 1888 and 1889 (see in French : rbmn). Arthur Constantin Krebs (November 16, 1850 in Vesoul, France - March 22, 1935 in Quimperlé, France) was a french officer and pioneer in automotive engineering. ... 1888 (MDCCCLXXXVIII) is a leap year starting on Sunday (click on link for calendar) of the Gregorian calendar or a leap year starting on Tuesday of the Julian calendar. ... Year 1889 (MDCCCLXXXIX) was a common year starting on Tuesday (see link for calendar). ...

Search and attack periscopes of a French-built Scorpène class submarine.

A modern submarine periscope incorporates lenses for magnification and functions as a telescope. It typically employs prisms and total internal reflection instead of mirrors, because prisms, which do not require coatings on the reflecting surface, are much more rugged than mirrors. It may have additional optical capabilities such as range finding and targeting. The mechanical systems of submarine periscopes are typically hydraulically powered and need to be quite sturdy to withstand the drag through water. The periscope chassis may also be used as to support a radio or radar antenna. Image File history File links Download high resolution version (598x771, 40 KB) fr: Périscopes de recherche et dattaque dun sous-marin de type Scorpene Image by B. Harry From http://www. ... Image File history File links Download high resolution version (598x771, 40 KB) fr: Périscopes de recherche et dattaque dun sous-marin de type Scorpene Image by B. Harry From http://www. ... Scorpène class submarines are a class of diesel-electric attack submarine jointly developed by the French company DCN and the Spanish company Navantia. ... 50 cm refracting telescope at Nice Observatory. ... If a shaft of light entering a prism is sufficiently small such that the coloured edges meet, a spectrum results In optics, a prism is a device used to refract light, reflect it or break it up (to disperse it) into its constituent spectral colours (colours of the rainbow). ... The larger the angle to the normal, the smaller is the fraction of light transmitted, until the angle when total internal reflection occurs. ...

Submarines traditionally had two periscopes: a navigation or observation periscope and a targeting, or commander's, periscope. These were originally mounted in the conning tower, one forward of the other in the narrow hulls of diesel-electric submarines. In the much wider hulls of recent US Navy submarines, the two are located side-by-side. The observation scope was used to scan the sea surface and sky and typically had a wide field of view and no magnification or low-power magnification. The targeting or "attack" periscope, by comparison, had a narrower field of view and higher magnification. In World War II and earlier submarines it was the only means of gathering target data to accurately fire a torpedo, since sonar was not yet sufficiently advanced for this purpose and most torpedoes were unguided.

However, the most modern submarines no longer use periscopes. The United States Navy's Virginia-class submarines instead use photonics masts, which lift an electronic imaging sensor set above the water. Signals from the sensor set are transmitted electronically to workstations in the submarine's control center. While the cables carrying the signal must penetrate the submarine's hull, that hull opening is much smaller and more easily sealed — therefore less expensive and safer — than those required by periscopes. Eliminating the telescoping tube running through the conning tower also allows greater freedom in designing the pressure hull and placing internal equipment. USN redirects here. ... The Virginia class (or SSN-774 class) of attack submarines are the first U.S. subs to be designed for a broad spectrum of open-ocean and littoral missions around the world. ...

See also

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School science/Demo periscope

• Vickers Tank Periscope MK.IV