A system for imaging a license plate of a vehicle entering a premises through an entrance, comprising: - a single optical camera at least capable of performing a pan operation to change its imaging direction based on received commands, - a distance measuring unit, - a detection area setting unit, - a vehicle detecting unit, - an imaging control unit, wherein the distance measuring unit is a laser radar apparatus configured to intermittently radiate a laser beam while rotating in a detection direction such as to scan along a scanning plane in the horizontal direction, and to receive reflection light of the laser beam, wherein the distance measuring unit measures the distance of an object that has reflected the laser beam based on the amount of time from radiation of the laser beam to reception of the reflection light, the laser radar apparatus being furthermore configured to recognize, as a point, the center of an object along the horizontal scanning plane, wherein the detection area setting unit is configured to virtually set, as data memorized by a memory, two or more detection area groups (7, 8, 9) from the entrance towards the inside of the premises in the real space, wherein each detection area group (7, 8, 9) is composed of a plurality of detection areas, wherein the detection area group closest to the entrance is referred to as first-stage detection area group and the detection area group furthest from the entrance is referred to as final-stage detection area group, wherein the detection areas in each detection area group (7, 8, 9) are rectangular-shaped, are aligned in the width direction, and are set so as to cover the overall area of the entrance in the width direction, and wherein the number of detection areas per detection area group increases from the entrance towards the inside of the premises, and the width-direction dimension of a single detection area becomes smaller, and wherein the detection areas are defined relative to an XYZ-coordinate system virtually set on the horizontal scanning plane, and wherein the groups of detection areas (7, 8, 9) are set such that the distance L between the group of detection areas closest to the entrance and the group of detection areas furthest from the entrance is set based on the expression L = tc * va, wherein "tc" is the maximum amount of time required to change the imaging direction of the camera, "va" is the estimated maximum movement speed of the vehicle, such that the vehicle 2 that is entering the premises can be tracked and imaging can be performed at the appropriate imaging location, wherein the vehicle detecting unit is configured to compare the coordinates on the horizontal scanning plane of the vehicle acquired from the distance measurement data with the coordinates of all detection areas (E11, E12; E21,... E24, E31... E38) to detect the detection area in which the vehicle that is entering the premises from the entrance G is present, wherein the imaging control unit is configured to control the optical camera to move its imaging direction towards the center of the detection area in which the vehicle detecting unit has detected the presence of the vehicle, and is furthermore configured to control the optical camera to perform imaging of the license plate of the vehicle when the positioning operation for a detection area of the final-stage detection area group has been completed. - a single optical camera at least capable of performing a pan operation to change its imaging direction based on received commands, - a distance measuring unit, - a detection area setting unit, - a vehicle detecting unit, - an imaging control unit,