A new method for measuring the luminosity distribution generated by lamps isintroduced. An image sensor is used to receive optical image signals and convert them intoelectric signals. The signals are then handled by hardware and software of a computer in themeasuring system and the luminosity distribution is found from the image data. The measuringprinciple, construction of the system, software design and factors that affect measuring precisionare discussed. Some suggestions are also put foreward for the purpose of improving themeasuring precision of the system.