Measurement method for luminous intensity from lamp with reflector - employs photocell system moving on carriage at constant distance on rails and incorporates proximity sensors

摘要

The luminous intensity of a lamp with reflector is measured in all directions by a photocell system which follows a circular trajectory whose centre passes through the photometric centre of the source. This locates the photocell at a constant distance from the resource. A photocell system (13) is carries on a carriage (14) which is guided by concentric rails (15, 16). An endless chain guides the carriage over the rails by means of pulleys and which is driven by a motor and reduction gear assembly (19). This allows a series of measurements to be made at angles (a) from the normal and at a constant distance (c) from the light source. Proximity sensors enable the carriage position to be controlled. A motor and gearbox assembly is able to modify the attitude of the light source so that the photocell can take another series of measurements.