An imaging system of a photo-curing 3D printing device, comprising: a light source to emit a light beam; a liquid crystal panel located on a light-emitting light path of the light source, wherein the liquid crystal panel contains a plurality of pixels; a first polarized light filter provided on an incident light side of the liquid crystal panel; a second polarized light filter provided on an emergent light side of the liquid crystal panel, wherein the first polarized light filter and the second polarized light filter cooperate with the liquid crystal panel to shield a part of the light beam so as to form a light beam image; a focusing lens array provided on the incident light side of the liquid crystal panel, wherein each focusing lens of the focusing lens array corresponds to each pixel of the liquid crystal panel, and each focusing lens can converge a light beam irradiated to a corresponding pixel, so that the light beam penetrates a light-transmitting region of the pixel as much as possible and an image of the light source is generated on the emergent light side of the liquid crystal panel, and the dimension of the image is smaller than the dimension of the light-transmitting region of the corresponding pixel; a projection lens disposed between the liquid crystal panel and a photosensitive material surface, which is located between the image and the photosensitive material surface, wherein the projection lens projects the light beam image onto the photosensitive material surface, so that the images of the light source generated by the focusing lens array form a plurality of light spots on the photosensitive material surface; and a deflecting lens disposed on the emergent light side of the liquid crystal panel, wherein the deflecting lens can deflect around at least one rotation axis perpendicular to an optical axis of the imaging system, so as to finely tune the position of the light beam image projected onto the photosensitive material surface; and a controller to command the light source to perform multiple exposures, and commands the deflecting lens to deflect during each exposure, so that light beam images during various exposures are projected to different positions of the photosensitive material surface. a light source to emit a light beam; a liquid crystal panel located on a light-emitting light path of the light source, wherein the liquid crystal panel contains a plurality of pixels; a first polarized light filter provided on an incident light side of the liquid crystal panel; a second polarized light filter provided on an emergent light side of the liquid crystal panel, wherein the first polarized light filter and the second polarized light filter cooperate with the liquid crystal panel to shield a part of the light beam so as to form a light beam image; a focusing lens array provided on the incident light side of the liquid crystal panel, wherein each focusing lens of the focusing lens array corresponds to each pixel of the liquid crystal panel, and each focusing lens can converge a light beam irradiated to a corresponding pixel, so that the light beam penetrates a light-transmitting region of the pixel as much as possible and an image of the light source is generated on the emergent light side of the liquid crystal panel, and the dimension of the image is smaller than the dimension of the light-transmitting region of the corresponding pixel; a projection lens disposed between the liquid crystal panel and a photosensitive material surface, which is located between the image and the photosensitive material surface, wherein the projection lens projects the light beam image onto the photosensitive material surface, so that the images of the light source generated by the focusing lens array form a plurality of light spots on the photosensitive material surface; and a deflecting lens disposed on the emergent light side of the liquid crystal panel, wherein the deflecting lens can deflect around at least one rotation axis perpendicular to an optical axis of the imaging system, so as to finely tune the position of the light beam image projected onto the photosensitive material surface; and a controller to command the light source to perform multiple exposures, and commands the deflecting lens to deflect during each exposure, so that light beam images during various exposures are projected to different positions of the photosensitive material surface.