A zoom lens including: a first lens array which has positive refractive power and which is in a fixed position relative to an image plane; a second lens array which has negative refractive power and which provides variable power by moving along an optical axis direction; a third lens array which has positive refractive power and which is in a fixed position relative to the image plane; a fourth lens array which has positive refractive power and which is capable of moving along the optical axis direction so as to maintain the image plane, which moves corresponding to movement of the second lens array and an object to be imaged, at a predetermined distance from a reference plane; a fifth lens array which has negative refractive power and which is in a fixed position relative to the image plane; and a sixth lens array which has positive refractive power and which is in a fixed position relative to the image plane. The first to sixth lens arrays are arranged in a first through sixth order, respectively, so that the first lens array lies adjacent to the object to be imaged.