3D printing procedure. (a) Initial position. (b) The moving arm moves toward the heated resin tank and touches the resin tank bottom (only a small height is left between the build plate and the resin tank bottom). (c) Then the laser beam solidifies the liquid resin captured inside of this height. (d) After the layer consolidating, the moving arm moves upward. (e) The moving arm returns to the initial position, and this process is repeated subsequently to form up the printing object ultimately.