Light control system

A lighting system comprising:

• a lamp arranged to transform electricity into a light beam having properties such as intensity, colour, colour temperature, direction and beam cone angle;
• a light control means arranged to adjust said light beam properties;
• an ultrasonic transmitter arranged to transmit ultrasonic signals;
• an ultrasonic receiver arranged to receive reflected ultrasonic signals;
• wherein said ultrasonic transmitter and/or receiver are mounted on a rotatable carrier such that the beam of said transmitter and/or the reception cone of said receiver extend parallel to and at a distance from the axis of rotation, wherein driving means are present to rotate said carrier;
• and
• a processing means arranged to send an ultrasonic pulse repeatedly through said transmitter during rotation at a multitude of angular positions of said carrier and to determine after each pulse is sent if said receiver receives a reflected ultrasonic signal with an amplitude exceeding a predetermined threshold within a predetermined period, and to send control signals to said light control means in dependence of said determination.