US Patent 7281794 Disposable ophthalmic lens

An ophthalmic lens with high definition, wide field of view and high magnification has, in one embodiment, a contact lens, an intermediate field lens and an image lens wherein a real image is formed inside the field lens. At least two of the lenses contribute to the magnification and three surfaces of the ophthalmic lens are aspheric to provide a better defined image. The ophthalmic lens is made disposable with high quality plastic lenses and a plastic holder. A portion of the holder changes appearance in response to change in environment to indicate that the disposable lens has been used.