| 摘要 |
<p>A detection system for detecting the position of an object on a movable member and particularly for detecting the position of a ball in a moving roulette wheel (1) comprises a light source (13, 14, 15) to emit visible light which is modulated. A sensor (16) is provided to receive reflections by the ball and the moving roulette wheel (1, 4) of said emitted modulated light. The reflections are analysed by appropriate means to determine the position of the member (4) and the location of the object in relation to the member (4). The light source (13, 14, 15) may transmit white light and the sensor (16) detect specific similarly modulated wavelengths, which are predetermined dependent on the relative chrominance of the numbers ring (5) and the pockets ring (6) of the roulette wheel (1), and the object. Alternatively, the light source (13, 14, 15) may transmit light of specific wavelengths which are predetermined dependent on the relative chrominance of the numbers ring (5) and the pockets ring (6) of the roulette wheel (1), and the ball, and the sensor (16) may detect similarly modulated wavelengths over the broadband visible light range.</p> |
