Wednesday, November 14, 2007

A general view on Glasses

The Glasses, spectacles, or eyeglasses are frames manner lenses worn in front of the human eyes, sometimes for just aesthetic reasons but in general for vision correction or eye protection. The Special glasses are used for viewing the three-dimensional images or experiencing virtual reality.

The Modern glasses are typically supported by pads on the bridge of the nose and by temples placed over the ears. The Historical types consist of the pince nez, monocle, and lorgnette. The Glasses are more often called eyeglasses in North American English, rarely spectacles in British English, and (rarely) frames or lenses. The Spectacles are often shortened to specs. In hipster jargon they are cheaters.

The Glasses were initially made from glass, but many are now made from plastic (often polycarbonate) because of the danger of breakage and the greater weight of glass lenses. Some plastics also have more beneficial optical properties than glass, like better transmission of visible light and better absorption of ultraviolet light. Some plastics have a greater index of refraction than the majority types of glass, allowing thinner lenses for a given prescription. Scratch-resistant coatings can be applied to most plastic lenses charitable them similar scratch resistance to glass. Hydrophobic coatings intended to ease cleaning are also obtainable, as are anti-reflective coatings designed to improve night vision and make the wearer's eyes more visible.

The Corrective spectacles have lenses created to correct vision abnormalities, like myopia. The Safety glasses are a type of eye protection against flying debris or noticeable and near visible light or radiation. The Sunglasses care for against high levels of visible and ultraviolet light.

Sunday, November 04, 2007

Types of Boxes

Permanent Boxes

Numerous types of boxes are used in eternal installations. Some types are designed to be for the time being inhabited by workers.

Permanent boxes include the following:

Equipment boxes - Fuse box

Compartments - Luxury box , Mailbox

Shelters or booths - Police box , Signal box , Telephone box

Permanent boxes

Numerous types of boxes are used in stable installations. Some types are designed to be provisionally inhabited by workers.

Permanent boxes include the following:

  1. Equipment boxes