Evidence suggests ancient civilizations, including the Greeks, may have had early optical knowledge and devices like ...

As [Huygens Optics] explains, mirrors ground to each of these shapes have different properties, which makes it hard to build telescopes that work at astronomical and terrestrial distances.

The latest deformable mirror from Edmund Optics (Barrington, New Jersey, USA) consists of 32 radially arranged actuators that control the shape of a 5-μm-thick nitrocellulose mirror membrane.