The optical non-contact operating VLM500 is a modern velocity and length measurement gauge in a compact housing. he optical non-contact operating VLM500 is a modern velocity and length measurement gauge in a compact housing. Based on the spatial filter principle the velocity is acquired continuously. The spatial filter is based on the filtering effect of grid-like structures (grid modulation) implemented by a CCDSensor. The resulting frequency is detected by the device. The frequency is proportional to the velocity of the object being measured. The length can be otained by integration. The object is illuminated by an integrated strong light source (LED). The light is reflected to the CCD-Sensor according to the surface morphology (granularity). Almost every surface can be measured that way. A fast adaption to the surface condition of the object is guaranteed by built-in control loops adjusting the exposure time and the brightness. According to the customer requirement the VLM500 can be equipped with several different industry interfaces or pulse outputs. The compactness and robstness of the gauge allows a space-saving and secure installation in facilities in various fields of the industry (metal, paper, wood, ceramic).