plastic lens

Definition: Optical component made from transparent plastics or optical resin. * Larger lenses, say more than 70mm diameter, may be machined and polished e.g. for spectacles; smaller ones are injection-moulded. * Not reserved for low-quality instruments: some good quality camera lenses may carry some plastics component e.g. moulded and fused onto a glass lens to create an aspheric surface.