Patent ID: RE41338

Claim:
An objective compound lens, applied to an optical scanner having at least a light source, a reflection compound mirror and an optical sensor, wherein the light source is used to radiate a document to obtain an image light, the reflection compound mirror is located in an optical path of the image light to project the image light on the optical sensor, and the objective compound lens is located between in the optical path of the image light between the optical sensor and the reflection compound mirror, the objective compound lens comprising: a basic objective lens having a first linkage , ; and a plurality of compound lenses having corresponding second linkage respectively, wherein any one of the second linkages is suitable for connecting and detaching with the basic objective lens via the first linkage; wherein when the basic objective lens is coupled to a selected one of the selected plurality of compound lens lenses located on the optical path of the image light between the basic objective lens and the reflection compound mirror, the optical scanner has a resolution corresponding to the selected compound lens, and when any one of the compound lenses is not connected to the basic objective lens, the image light is projected on the optical sensor via the basic object objective lens only.