Device for monitoring parked vehicles

A parking control unit intended primarily for checking whether or not a parking fee has been paid in respect of a parked vehicle, wherein the parking control unit is intended for use in a parking system of a kind in which the user registers an account number and the vehicle registration number at the commencement of a parking period and again registers the account number at the end of the parking period, and wherein the account number, the registration number, the parking commencement time and the parking termination time are stored in the memory of a central computer (6) so that the parking time that has lapsed between the parking commencement time and the parking termination time can be billed to the account number concerned, which parking control unit (1) is portable and includes a display (2), a computer unit (3) and associated memory (4), and a communication unit (5) adapted to communicate with the memory of said central computer (6) to obtain information relating to the registration numbers of those vehicles that have commenced a parking period in the parking system but have not terminated parking, characterized in that the parking control unit (1) includes an optical picture reproducing device (7) adapted to reproduce an image of the registration plate of a vehicle in that it includes a low-power laser (13) which functions as a sighting means by means of which the parking control unit (1) is brought into alignment with the center part of a vehicle registration plate by a parking attendant, whereafter recording of the registration plate takes place, and in that the parking control unit (1) is arranged to make clear or clarify said imaged registration number;

• and in that the parking control unit is adapted to compare the clarified registration number with those registration numbers of vehicles that have commenced a parking period but have not terminated parking in the system and to indicate through the medium of an indicator (2) whether or not the clarified registration number belongs to a vehicle that has commenced a parking period but has not terminated parking in the system.