Non-contact detection of velocity and length in the converting and textile industry
Precise, reliable and non-destructive length and velocity measurement is of the utmost importance in the converting and textile industry. Even the smallest deviation can cause added material costs which can quickly add up. That is why high-precision non-contact measuring processes are absolutely imperative.
Polytec's laser surface velocimeters (LSVs) have been specially designed for high-precision velocity and length measurement. Polytec LSVs provide you with reliable measurement data that you can easily integrate into your process control systems. Using an LSV means increasing precision and thereby increasing the quantity and quality of your output. Your advantages: Polytec's non-contact measuring technique works on almost all surfaces and removes any chance of damaging the measured product. From precision position monitoring in printing processes right through to cutting length control for packaging materials – Polytec systems ensure that you obtain the perfect configuration for every application.
ProSpeed optical length and speed sensors measure with the utmost reliability around the globe and support the converting and textiles industry...
- in printing processes
- in laminating and coating systems
- and many more applications.
High-precision detection of velocity differences
Any required velocity difference should be regulated accordingly in processes which involve the elongation of products. In other processes differences are undesirable since they can lead to backlogging or even damage to the product – due, for example, to the slippage of drive rollers or to tension generated in the product. The velocity difference is calculated by measuring the velocity at different points in the process and comparing the readings with one another.
Using several laser surface velocimeters (LSV) allows you to accurately determine the velocity at relevant points in the process, thereby enabling you to optimize it.
LSVs from Polytec are ideally suited because they can conduct measurements on almost any surface and they are not susceptible to contaminated surfaces. The non-contact measuring technique makes it possible to eliminate any negative influences on accuracy, such as slippage and wear, in one go. The product being subjected to the measurement remains unaffected.
The increased accuracy of velocity measurement allows you to monitor the velocity difference more closely. As a result you are better able to adhere to the end product requirements. The result: You increase quality while at the same time reducing waste.
Practical examples:
Polytec LSVs are used for a variety of velocity difference measurements in the converting and textile industry:
- synchronization of individual sheets in longitudinal cutting processes
- synchronization of roll and sheet in winding and unwinding processes
- tension monitoring

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LSV-1000 Laser Surface Velocimeter
The compact velocimeter for performing non-contact length and velocity measurements on strip products.
Velocity measurement on roll-fed material and piece goods
Velocity measurement is indispensable for process control and optimization in many industrial processes. It is the basis for many other applications such as cut length control, length measurement and velocity difference measurement. In these processes velocity is measured using the laser Doppler technique.
Laser surface velocimeters (LSVs) from Polytec are ideally suited because they can conduct measurements on almost any surface and they are not susceptible to contaminated surfaces. The non-contact measuring technique makes it possible to eliminate any negative influences on accuracy, such as slippage and wear, simultaneously. The product being subjected to the measurement also remains intact.
Another benefit of Polytec systems is the flexible interface concept enabling velocity readings via encoder output, serial interfaces, LAN, Profibus and Profinet.
Practical examples:
Polytec LSVs are used for various velocity measurement tasks in the converting and textile industry:
- dwell time determination in coating and surface treatment systems
- control of cutting devices in cut-to-length processes
- coil synchronization when winding sheet materials
Conveyor and drive belt length measurement
In a specific application, a world leading manufacturer of conveyor and drive belts uses several Polytec LSVs for carrying out length measurements at cutting stations. This means that customer-specific cuts can be automated, simplifying the process significantly. The cut-to-length accuracy using the LSV is independent of the belt surface and achieves a precision of 0.1%

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Change cookie settingsRelated products

LSV-1000 Laser Surface Velocimeter
The compact velocimeter for performing non-contact length and velocity measurements on strip products.
Length measurement on roll-fed material and piece goods
Determining the velocity provides the basis for measuring the length. The length is calculated based on the velocity profile while the measured object passes through the measuring location. LSV Laser Surface Velocimeter automatically recognize whether the material is in the correct measuring position and can start/stop the length measurement accordingly. To achieve maximum measurement accuracy the LSV offers you the option of connecting light barriers as a means of starting or stopping the length measurement. This means you can link up several light barriers with one another to obtain a variety of application options. This may include, for example, controlling the length measurement using both trigger inputs, thereby increasing accuracy.
Laser surface velocimeters (LSVs) from Polytec are ideally suited because they can conduct measurements on almost any surface and they are not susceptible to contaminated surfaces. The non-contact measuring technique makes it possible to eliminate any negative influences on accuracy, such as slippage and wear, simultaneously. The product being subjected to the measurement also remains intact.
Another benefit of Polytec systems is the flexible interface concept – it enables length readings via encoder output, serial interfaces, LAN, Profibus and Profinet.
Practical examples:
Polytec LSVs are used for a variety of length measurement processes in the converting and textile industry:
- winding sheet materials
- cutting-to-length during fabrication
- position sensing in printing processes
Conveyor and drive belt length measurement
In one specific case, a world leading manufacturer of conveyor and drive belts uses several Polytec LSVs for carrying out length measurements at cutting stations. This means that customer-specific cuts can be automated, simplifying the process significantly. The cut-to-length accuracy using the LSV is independent of the belt surface and achieves a precision of 0.1%

Dear visitor, in order to be able to watch our videos please accept the cookies. All information about the usage of cookies can be found in our privacy policy
Change cookie settingsRelated products

LSV-1000 Laser Surface Velocimeter
The compact velocimeter for performing non-contact length and velocity measurements on strip products.

LSV-2000 MID Laser Surface Velocimeter
The compact and MID-certified speed and length sensors for calibrated equipment – perfect if you’re selling products by length like common in converting processes. It is certified in line with 2014/32/EU (MID Measuing Instruments Directive).
Tension control on sheet materials
Processing sheet materials means keeping the sheet tensioned. If the tension is too little, then the product "sags" and may become entangled. If it is too much, then the product can become overstretched and end up becoming damaged or ripped as a result. In order to accurately determine this tension between two different points in the process, it is essential to measure the velocity at both points. You can then calculate the tension from the difference.
Laser surface velocimeters (LSVs) from Polytec are ideally suited because they can conduct measurements on almost any surface and they are not susceptible to contaminated surfaces. The non-contact measuring technique makes it possible to eliminate any negative influences on accuracy, such as slippage and wear, in one go. The product being subjected to the measurement also remains intact.
The increased precision in velocity measurement enables you to monitor the tension more closely, thereby optimizing the process while preventing the product from being damaged by tension fluctuations. The result: You increase quality while at the same time reducing waste.
Practical examples:
Polytec LSVs are used in various applications in the converting and textile industry as a means of regulating tension:
- in joining sheet materials, i.e while changing rolls of film and packaging materials
- when processing sensitive material such as thin films

Related products

LSV-1000 Laser Surface Velocimeter
The compact velocimeter for performing non-contact length and velocity measurements on strip products.