Basic principles of laser Doppler vibrometry

Laser vibrometry is a high precision optical measurement method for the non-invasice determination of vibrational velocity and amplitude of a sample surface. Based on the Doppler effect it evaluates the frequency shift of backscattered laser light from a moving object surface. Learn more about the measurement principle and interferometer setup in this new video.

Watch the video

Areas of technology


Laser vibrometers developed and manufactured by Polytec define the globally recognized standard for optical vibration measurement. We provide our customers from a wide variety of industries a comprehensive range of solutions for almost any vibration-related challenge in research, development, production and condition monitoring. Laser Doppler vibrometers are precision measuring instruments for the examination of objects of almost any size and solve your task quickly, in a non-contact, non-destructive manner. 


When producing continuous material and piece goods, knowing the exact length and velocity is key if you are to optimize your costs and processes. Non-contact laser surface velocimeters make reliable process control possible, based on the laser-precise measurement of length and speed, even in harsh ambient conditions. Designed for their robustness, reliability and minimum maintenance requirements.

Surface Metrology

The TopMap surface measurement family can be used for characterization of rough, smooth or stepped surfaces using our innovative white light interferometry system for high precision and non-contact results.  Already used in laboratories worldwide for research and development, quality assurance and within production environments and directly on manufacturing lines. 

Machine Vision

In order to select the ideal combination of components for each customer requirement, Polytec offers a comprehensive product range of lighting, sensors, cameras, lenses and accessories in the machine vision area. Putting together individual solutions for your needs from this large machine vision portfolio is our specialty – with our decades of experience as a distributor, manufacturer and service provider of solutions in an industrial environment.

Optical Systems

The field of optical systems comprises the greatest variety at Polytec, both in terms of technology and products: from optical, electro-optical and electrical measurement technology for laboratory, field and production applications to optical sources across all spectral ranges. In this huge photonics product range, we always keep track of what’s going on: our consulting engineers and service technicians will find the optimal measurement solution for your specific measurement task.

Process Analytics

Reducing costs while increasing quality, efficiency and output: Polytec provides spectroscopic measurement solutions for a wide range of routine analytical and/or industrial applications, from incoming material inspection through manufacturing processes and final product quality control. Fast, robust and precise near-infrared (NIR) spectrometer systems allow to determine the chemical composition and concentration of materials non-destructively and in real-time. This established technology is implemented in numerous industries for quality control applications.

When surface metrology becomes surface quality 

For measuring the finest details in surfaces by areally characterizing form parameters without contact, the TopMap optical profilers are the preferred solution. From microscope to macroscope quality control applications, Polytec offers turnkey surface metrology solutions for industry and research.

Learn more

Polytec events

Visit Polytec around the world at trade fairs and conferences, or sign up to one of our online seminars, user meetings or customer seminars to find out more about the principles, advantages and various uses of optical measuring technologies!

Learn more