A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways.
A Fresnel lens is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships."
A kerosene lamp is a type of lighting device that uses kerosene as a fuel. Kerosene lamps have a wick or mantle as light source, protected by a glass chimney or globe; lamps may be used on a table, or hand-held lanterns may be used for portable lighting. Like oil lamps, they are useful for lighting without electricity, such as in regions without rural electrification, in electrified areas during power outages, at campsites, and on boats. There are three types of kerosene lamp: flat-wick, central-draught, and mantle lamp. Kerosene lanterns meant for portable use have a flat wick and are made in dead-flame, hot-blast, and cold-blast variants.
A parabolicreflector is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis. The parabolic reflector transforms an incoming plane wave travelling along the axis into a spherical wave converging toward the focus. Conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis.
The history of lighthouses refers to the development of the use of towers, buildings, or other types of structure, as an aid to navigation for maritime pilots at sea or on inland waterways.
The Baily Lighthouse is a lighthouse on the southeastern part of Howth Head in County Dublin, Ireland. It is maintained by the Commissioners of Irish Lights.
The New Presque Isle Light was built in 1870, at Presque Isle, Michigan, east of Grand Lake, and sits on the namesake peninsula. It is one of 149 lighthouses in Michigan, more than any other state. Because of changing shoreline particularly, or alternatively deterioration of the original building, it is not uncommon for a replacement lighthouse to be placed in the vicinity of an earlier light, in this case, the Old Presque Isle Light.
A Fresnel lantern is a common lantern used in theatre that employs a Fresnel lens to wash light over an area of the stage. The lens produces a wider, soft-edged beam of light, which is commonly used for back light and top light.
Stage lighting instruments are used in stage lighting to illuminate theatrical productions, concerts, and other performances taking place in live performance venues. They are also used to light television studios and sound stages.
Alcatraz Island Lighthouse is a lighthouse—the first one built on the U.S. West Coast—located on Alcatraz Island in California's San Francisco Bay. It is located at the southern end of the island near the entrance to the prison. The first light house on the island was completed in 1854, and served the bay during its time as a Citadel and military prison. It was replaced by a taller concrete tower built in 1909 to the south of the original one which was demolished after it was damaged due to earthquake in 1906. The automation of the lighthouse with a modern beacon took place in 1963, the year Alcatraz closed as the Alcatraz Federal Penitentiary. It is the oldest light station on the island with a modern beacon and is part of the museum on the island. Although when viewed from afar it easily looks the tallest structure on Alcatraz, it is actually shorter than the Alcatraz Water Tower, but as it lies on higher ground it looks much taller.
The Source Four PAR is a stage lighting instrument manufactured by Electronic Theatre Controls. The name of the fixture derives from the stylistic and construction features it shares with ETC's Source Four. The suffix identifies the Source Four PAR as a parabolic aluminized reflector (PAR). It is designed and marketed as a modern, energy efficient alternative to traditional PAR fixtures used in theatrical and broadcast lighting.
Cromer Lighthouse is situated in the coastal town of Cromer, in the English county of Norfolk.
Gay Head Light is a historic lighthouse located on Martha's Vineyard westernmost point off of Lighthouse Road in Aquinnah, Massachusetts.
Lange Jaap, also known as Kijkduin Light or Den Helder Light, is an active lighthouse near Fort Kijkduin in Huisduinen, Netherlands. At a height of 63.5 metres (208.2 ft) it is one of the tallest "traditional lighthouses" in the world. For almost a century, from 1878 to 1974, it was the tallest lighthouse in the Netherlands, until the construction of the Maasvlakte Light. According to The Lighthouse Directory it is the tallest non-skeletal cast iron lighthouse in the world.
An aerobeacon is a light assembly used to create a fixed or flashing signal visible over long distances. It consists of a high intensity electric lamp mounted with a focusing device in a cylindrical housing, which usually is rotated on a vertical axis by an electric motor. The sweep of the narrow beam thus produced gives the flashing effect. Aerobeacons were originally developed for aviation use, mostly as aerodrome beacons, but they also saw extensive use in lighthouses. They were far less expensive to manufacture and maintain than classic glass Fresnel lenses, and much more durable; they could be mounted and exposed to the weather. Historic models include the DCB-24, which used a single parabolic reflector; the DCB-224, a double-beamed version of the DCB-24; and the DCB-36, which used a system of plastic Fresnel type lenses. Manufacturers included Carlisle & Finch in Cincinnati and the Crouse-Hinds Company in Syracuse, New York. Aerobeacons have replaced fragile glass Fresnel lenses in many lighthouses and are still widely used in other applications.
The Old Higher Lighthouse is a disused 19th century lighthouse on the Isle of Portland, Dorset, southern England. It is located at Branscombe Hill on the west side of Portland, overlooking Portland Bill. The lighthouse is Grade II Listed.
Grand Turk Lighthouse is a lighthouse on Grand Turk Island, Turks and Caicos Islands. The 60-foot-tall (18 m) structure, overlooking North Creek, was completed by British architect Alexander Gordon in 1852 to alert sailors of the shallow reef. Brighter kerosene lamps and a more powerful Fresnel lens were added by the Chance brothers in 1943 and remained in use until 1972 when the lighthouse was electrified. Today, the lighthouse and lighthouse keeper's house are a historic site under the protection of the National Trust.
The Esteiro Lighthouse is an active Portuguese lighthouse located at Oeiras, about 10 km west of the centre of Lisbon, in parkland that also contains the National Stadium of Portugal. It is a rectangular masonry tower covered with white tiles. The south side has two red horizontal bands that serve as identification during daylight.
The Bugio Lighthouse is situated on an island in the estuary of the River Tagus on the Fort of São Lourenço do Bugio, about ten kilometres west of Lisbon. It falls under the municipality of Oeiras in Lisbon District.
The São Julião Lighthouse is located in the fort of the same name, which is the largest sea defence structure in Portugal and is situated on a headland on the north bank of the River Tagus estuary in Oeiras, Lisbon District. It is a square masonry tower and the lantern is painted white, with a red dome.
