The technical definition of a telephoto lens is one with a focal length greater (or longer) than 50mm (on the 35mm/full frame forma), but the telephoto range is more generally accepted to begin at ...

Inserting any material into a special maze of mirrors and lenses can make it absorb light perfectly. This approach could be used to detect faint starlight or for charging faraway devices with lasers.

A surprising trick that allows a beam of light to be completely absorbed even in the thinnest of layers: Using mirrors and lenses, a 'light trap' can be constructed, in which the light beam is ...

Researchers say trial participants could perceive information in infrared light even when they closed their eyes ...

An international team led by Chinese scientists has developed revolutionary contact lenses that allow humans to see ...

Contact lenses and eyeglasses could one day enable people to see beyond the natural visible light spectrum. Eyewear equipped ...

Most professional instruments use large mirrors and do not have corrector ... distort the incoming light, and ruin the quality of any data gathered. Amateur astronomers also are often surprised ...

That's why observatory and space-based telescopes rely on massive, curved mirrors instead to achieve the same light-bending ...

A refractor uses lenses to refract light and bring it to a focus. Reflectors utilize at least two mirrors to reflect the light to a focal point. Because large lenses are heavy and expensive to ...