acquiring N×M source images of a sample using a light source of each of N×M (N and M are integers of 3 or more) light-emitting elements arranged in a matrix structure;

selecting n×m (n is an integer less than N and m is an integer less than M) images among the source images based on a central image using a central light-emitting element, located at a center of the matrix structure, as a light source, performing a Fourier Ptychographic Microscopy Process (FPMP) on the n×m images, and reconstructing a low-resolution, large-area image;

detecting a partial region containing a detection target object from the low-resolution large-area image, and acquiring partial-region images matching the partial region from each of the source images; and

performing FPMP on the partial-region images and reconstructing a high-resolution image on the partial region,

wherein the reconstructing of the high-resolution image on the partial region comprises:

determining overlapping images, in which a dark field (DF) and a bright field (BF) exist in a preset ratio, among the N×M source images,

acquiring partial-region images from the remaining images except for the overlapping images among the N×M source images, and

performing FPMP on partial-region images acquired from the remaining images except for the overlapping images,

wherein the determining of the overlapping images comprises:

confirming an image group corresponding to an index (2k+1, 2k+1) assigned to an outer row and column image group from the central image based on an index (1,1) assigned to the central image;

confirming a DF and BF ratio of each image belonging to the image group corresponding to the (2k+1, 2k+1), and

deleting the image group corresponding to the (2k+1, 2k+1) from the source images when the number of images having DF and BF in the preset ratio among images belonging to the image group is two or more, and

wherein the source images are distinguished by indexes matching respective positions of N×M light-emitting elements arranged in a matrix form, an index assigned to the central image is (1,1), and an index assigned to an image group using light-emitting elements, arranged outside by k rows or k columns from the central light-emitting element, as a light source is (2k+1, 2k+1), where k=1,2,3 . . . (M−1)/2, and an image group corresponding to the (2k+1, 2k+1) is composed of {(2k+1)×(2k+1)}−{(2k−1)×(2k−1)} images.