Lens

Lens may refer to:

Optics

Other radiation focus and forces

Places

Lens (optics)

A lens is a transmissive optical device that affects the focus of a light beam through refraction. A simple lens consists of a single piece of material, while a compound lens consists of several simple lenses (elements), usually along a common axis. Lenses are made from transparent materials such as glass, ground and polished to a desired shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly refract radiation other than visible light are also called lenses, such as microwave lenses or acoustic lenses.

History

The word lens comes from the Latin name of the lentil, because a double-convex lens is lentil-shaped. The genus of the lentil plant is Lens, and the most commonly eaten species is Lens culinaris. The lentil plant also gives its name to a geometric figure.

The variant spelling lense is sometimes seen. While it is listed as an alternative spelling in some dictionaries, most mainstream dictionaries do not list it as acceptable.

Lens (surname)

Lens is a surname. Notable people with the surname include:

Mimas (genus)

Mimas is a genus of moths in the Sphingidae family.

Species

Karaburun

Karaburun is a district and the center town of the same district in Turkey's İzmir Province. The district area roughly corresponds to the peninsula of the same name (Karaburun Peninsula) which spears north of the tourism resorts of neighboring Çeşme and its dependencies and west of the city of İzmir. In fact, the district area is one of the westernmost points of Anatolia. Karaburun town is situated close to the northern tip of the peninsula and checks the entry of the Gulf of İzmir with the town of Foça, another important tourism resort, across the waters. The district's administrative zone is bordered by the districts of Çeşme and Urla in its south and faces the Greek island of Chios to its west.

Karaburun region is comparatively much less visited than Çeşme located in its south, its rate of urbanization at 20 per cent is the lowest across İzmir Province, although it provides an anticlimax to its southern neighbor and the associated attractions especially for those who want to escape the trails of mass tourism. The coasts of the peninsula have beautiful bays and pebble or sand beaches as yet often undiscovered by outsiders, although there is one German vacation village slightly to the north of the district center. Taken as a whole, in contrast with Çeşme, agriculture, fishing and livestock breeding, instead of tourism, remain the principal activities on which the district's economy is based. Karaburun's flora and fauna present particularities distinguishing it from the Anatolian mainland. Karaburun's name echoes in Turkey a very high variety of flower breeds present across its area, and especially narcissus and hyacinth.

Mimas (moon)

Mimas is a moon of Saturn which was discovered in 1789 by William Herschel. It is named after Mimas, a son of Gaia in Greek mythology, and is also designated Saturn I.

With a diameter of 396 kilometres (246 mi) it is the smallest astronomical body that is known to be rounded in shape because of self-gravitation.

Discovery

Mimas was discovered by the astronomer William Herschel on 17 September 1789. He recorded his discovery as follows: "The great light of my forty-foot telescope was so useful that on the 17th of September, 1789, I remarked the seventh satellite, then situated at its greatest western elongation."

Name

Mimas is named after one of the Giants in Greek mythology, Mimas. The names of all seven then-known satellites of Saturn, including Mimas, were suggested by William Herschel's son John in his 1847 publication Results of Astronomical Observations made at the Cape of Good Hope. He named them after Titans specifically because Saturn (the Roman equivalent of Cronus in Greek mythology), was the leader of the Titans and ruler of the world for some time.