The invention relates to an eye-surgical laser apparatus, a use of said apparatus, and to a method for scanning the corneal tissue of an eye before or during eye surgery. The apparatus comprises optics that are adapted to focus a laser beam at a focus within a corneal tissue of an eye, and a detection element adapted to detect light that is formed, at the focus, as a frequency multiple and backscattered or forward emitted. Image information about the inner corneal tissue is then produced from the detected light.