Driver apparatus and method

• Main Authors: COLINS, STEELE, DAVID PAUL, SINGLETON, CATHERINE ANN, HEARNE
• Format: Patent
• Language: Chinese; English
• Published: 01.07.2013
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERATION; PICTORIAL COMMUNICATION, e.g. TELEVISION

A light source array comprises at least first and second light sources L1, L2, each light source L1, L2 having a respective switch S1, S2 connected in series. The second light source L2 and second switch S2 are connected in parallel with the first light source L1 and first switch S1. The light source array may be used, for example, for illuminating a scan region on a target object, wherein light reflected from said target object is captured by a detector. A shunt path 50 comprising a switching device S4 is provided in parallel with the LED array and switching array. The shunt path 50 has the advantage of enabling the switching sequence from one LED to another to be controlled such that a substantially constant current is drained from the supply (subject to any differences in the inherent current drawn by the respective light sources).