A method of photo-curing a photo-sensitive resin is disclosed in the present invention. The method includes the following steps: generating a sub-pixel pattern having an outer contour region and an inner contour region based on a vector file taken from a cross-section of a model; providing the sub-pixel pattern to a photomask module, wherein the photomask module includes a panel having a pixel matrix including plural square pixels, each of which includes three color-filtered sub-pixels; flood-filling color in each of the color-filtered sub-pixels to distinguish the outer contour region from the inner contour region; and exposing the photo-sensitive resin to a light source emitting a light passing through the panel.
