Politically, Ireland is divided between the Republic of Ireland (officially also named Ireland), which covers five-sixths of the island, and Northern Ireland, a part of the United Kingdom, which covers the remaining area and is located in the northeast of the island.orthern Ireland is a part of the United Kingdom with a local executive and assembly which exercise devolved powers. The executive is jointly headed by the first and deputy-first minister, with the ministries being allocated in proportion with each party's representation in the assembly. Its capital is Belfast.
Lens (optics) For other uses, see Lens. A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis.
Image erecting optical system for astronomical telescopes (Erecting eyepiece). In optics, a relay lens is a lens or lens group that inverts an image and extends the optical tube. Relay lenses are found in endoscopes and periscopes for the purpose of extending the system, and before eyepieces for the purpose of inverting an image.