Abstract: An optical system for the attenuation of laser light for measurement purposes which includes four logical subassemblies including a first attenuator subassembly for the attenuation of high power laser light, a second attenuator subassembly for lower power attenuation of the laser light, a third lens subassembly for collecting beam size data simultaneously at multiple locations in space, and a fourth logical subassembly including a beam measuring assembly for recording the beam size data received from the lens subassembly for analysis of the beam characteristics. The first attenuator subassembly is provided with a pair of reflecting, opposed facing, fixed wedges. The reflecting wedges are selectively tilted to eliminate interference effects between their inward facing reflecting surfaces. The second attenuator subassembly further includes a pair of opposed facing and movable wedges arranged in series with a fixed filter.