Mechanical vibrations are almost invisible to the human eye. Nevertheless, they are often the cause of undesired sound emissions, disturbances or even damage. These can occur on the body, engine or gearbox of motor vehicles or can cause damage to machines and buildings. To avoid them, they must be made visible first. laser Doppler vibrometers provide a convenient way to visualize vibration by means of optical and non-contact vibration measurements, and thus, is usable for nearly all kinds of surfaces independent from their temperature. Even glowing or deep black objects can be easily measured.