Noise, vibration, and harshness (NVH) is the study and modification of the noise and vibration characteristics of vehicles. Interior NVH deals with noise and vibration experienced by the occupants of the cabin, while exterior NVH is largely concerned with the noise radiated by the vehicle, and includes drive-by noise testing.

Scanning Vibrometry is an essential tool for effective NVH optimization. The vibrational characteristics of a sample is aquired full field under operational or excited conditions. The results represent the actual vibrations. No added mass is influencing the measurement, as the sensor is light itself.