Compact lens for digital image acquisition and image acquisition device

摘要

The invention relates to a compact lens with fixed or variable focal length for digital image acquisition. According to the invention, a refractive optical element of the lens or a group of elements on a light entry side of the lens is provided as a compound lens having a first lens element from a glass or optical ceramics with a first index of refraction and a second lens element from a plastic with a second index of refraction which is smaller than the first index of refraction, the first lens element being located on the beam path in front of the second lens element and on a light entry side of the lens. The lens also comprises at least one diffractive optical element. With a compactly built lens, imaging errors can thus be minimized by simple means. The diffractive optical element directly on or at a transparent cover is preferably made or provided for covering the detector array. Another aspect of the invention relates to a digital image acquisition device with such a lens.