Concrete crack detection device and method, and terminal system

The invention discloses a concrete crack detection device. The concrete crack detection device comprises a holder, a camera, a light source, a laser ranging module and an image processing display module, wherein the light source and the laser ranging module are fixed on the holder side by side; the camera, the light source and the laser ranging module are arranged on the holder side by side in a pluggable mode; the holder is used for keeping an attitude of the camera; the light source provides illumination for the camera; the laser ranging module is used for measuring distances between three points on an imaging plane of the camera and a surface to be detected; the camera is used for acquiring a crack image of a concrete structure; and the image processing display module is used for controlling the camera, the holder, the light source and the laser ranging module to perform analytic processing on the crack image acquired by the camera according to a user instruction and displaying a result of analytic process