The continuous development of new authentication techniques is necessary to prevent illegal data access from unauthorized users or counterfeiting. In this paper, we present a simple optical method to decode encrypted images using a multi-scopic optical system. The method uses a scrambled lens-let array which provides a high level of security. In a simple configuration, the encrypted image is scrolled in front of the multi-scopic imaging system. Due to a particular arrangement of lens-lets, the image will only be correctly imaged at a unique position with respect to the imager. Experimental demonstrations are presented and potential applications discussed.