System for rear projection of jointing wall and adjusting method thereof

A system for rear projection of a jointing wall comprises at least two display units. Each display unit comprises projection units provided with first optical axes, screen units respectively corresponding to the projection units and provided with second axes and at least one optical axis adjustor respectively corresponding to the projection units and respectively adjusting the relative positions of the first optical axes and the corresponding second axes, wherein the first optical axes of the projection units in at least one display unit do not coincide with the second axes of the screen units. 种背投影拼接墙系统，包含至少两个显示单元：显示单元包含投影单元，具有第光轴；屏幕单元，分别对应于该投影单元，具有第二光轴；以及至少个光轴调整器，分别对应于该投影单元，并分别调整该第光轴与相对应的第二光轴相对位置。其中至少个显示单元内的投影单元第光轴与屏幕单元第二光轴不重合。