1. A method of obtaining an image of an imaging region using an active imaging system that includes a laser, and an image generation device including an image sensor, the image sensor having a limited Field of View (FoV) that is smaller than an FoV required for the image sensor to capture the entire image region, the method comprising: irradiating a beam of the laser sequentially to a plurality of portions of the imaging region; using the image generation device without mechanical move thereof, to refract light reflected sequentially from the plurality of portions of the imaging region, and to receive the sequentially refracted light; and generating, using the image generation device, a plurality of sequential images based on the sequentially refracted light, and generating the image of the imaging region based on the plurality of sequential images and sequential angular information of the beam, wherein the sequential images are generated by sequentially irradiating the beam at a plurality of angles respectively to the plurality of portions of the imaging region, and the reflected light is refracted through a prism in the image generation device.