The invention discloses a
wavefront detection device and method for an edge sub-mirror in a spliced mirror. An interferometer and a
laser tracker are combined for use; the
wavefront of the edge sub-mirror in the spliced mirror is detected by compensating aberration through a computer-generated hologram sheet; the
wavefront detection device comprises a high-precision
plane mirror, a lifting frame,the detected edge sub-mirror, an inclination adjustment device, the computer-generated hologram sheet, a small five-dimensional adjustment table, a standard lens, the interferometer, a
vibration isolation platform, a five-dimensional adjustment table, the
laser tracker and a target ball. A space coordinate
system of the interferometer, the measured edge sub-mirror and the
plane mirror is established by using the
laser tracker; and the computer-generated hologram sheet is palced to be aligned with the interferometer, the interferometer and the computer-generated hologram sheet are taken as a whole, the
pitch and inclination of the whole are finely adjusted to form an auto-collimation light path, and adjustment is carried out until an aberration item in a wavefront detection result of the interferometer is minimum, thereby obtaining the wavefront detection result of the detected edge sub-mirror.