Primes GmbH has introduced the MSM MicroSpotMonitor for controlling and checking small laser beam dimensions such as those used in micromachining applications. It measures power density distribution at different Z-positions of the beam within a few minutes. From that data, the dimension of the focused laser spot, the focus position in space and the beam propagation ratio M2 are calculated. The device is suitable for use with pulsed and CW lasers, with spot dimensions from <10 to 2000 µm. It measures power densities of >100 GW/cm2, and the maximum peak pulse power is >100 kW and dynamic range, 120 dB.