The Luminous flux, illuminance and Brightness are the most basic physical quantity in photometric test. PH3000 Transit Photometer is developed base on rapid sampling techniques. It applied with 12 Bytes, the maximum sampling rate of 10M Hz high-speed A / D which can be achieved rapidly high speed measurement of varying light photometric parameters. Combined with computer can record the sampled waveform. The PH3000 also can used as normal illuminance meter, it can measuring luminous flux, brightness, illuminance and photometric parameters.