Interference-free, reliable measurements in demanding environments
With the help of fibre optic measurement solutions (WLPI: white light polarisation interferometry) from ALTHEN, you can measure strain, pressure, displacement and temperature. Interfering effects such as high voltage or EMC often limit the functionality of conventional electronic sensors. This is where our systems come into play: they create new possibilities for reliable measurements, especially in these environments.
We offer standard fiber optical sensors but can also help you with a customized design or a complete measurement solution.
White light polarisation interferometry (WPLI) is a patented fibre optic technology that enables precise measurements in the most demanding applications. It offers maximum flexibility in sensor design so that you can perform reliable measurements even under the most adverse conditions. These include, for exampleeasy adaptation of the fibre optic cablesimple mounting andthe option of fully integrating a sensor into a component - from the size of a credit card. Including all the necessary components for signal evaluation.You can record all available measured variables with the same signal evaluation unit.
Fibrer optical strain sensors are used for the precise measurement of deformations. These sensors are suitable, for example, for
Fiber optical pressure sensors can be used for highly accurate pressure measurements - even in the most demanding environments. Due to their small dimensions, insensitivity and reliability, these sensors are suitable for applications such as research and industrial applications.
Fibre optic displacement sensors have a long service life and are suitable for the most demanding applications where high reliability is a must. They are ideal for all industrial applications such as
Fiber optical temperature sensors are used to create temperature profiles. A typical fiber optic temperature sensor is the single-point sensor, which is located at the tip of the fibre. Glass fibres are insensitive to electromagnetic radiation. They can therefore also be used without any problems in high voltage potentials, in potentially explosive atmospheres or in chemically aggressive environments. They are frequently used for
We have the right fiber optic sensor for every application. We are happy to support you in your selection. At Althen, we draw on more than 45 years of experience to offer you the optimum solution, tailored to your requirements. This also includes customised fibre optic sensors as a complete package. The advantage for you is that we are not tied to one manufacturer and can advise you independently. On request, we can customise the measuring system exactly to your needs. Do you have any questions? We are here to help you!
With fiber optic measurement solutions you can measure strain, pressure, displacement or temperature. Conventional electronic sensors are often hampered by distorting effects such as high voltage or EMV. This is where our systems come in: they open up new possibilities for reliable measurements, especially in the most challenging environments.
Fiber optic white light polarisation interferometry is a patented technology. It enables precise measurements in the most demanding applications. WLPI allows great flexibility in sensor design for reliable measurements even in the most challenging environments.
Fiber optic measuring systems comprise two main components: the fiber optic sensor and a signal processing unit. The fiber optic sensor consists of a sealed housing that contains the optical sensor element and an optical fiber, which serves different purposes depending on the technology used.
There are several fiber optic measuring procedures based on different properties of light (intensity, phase, polarisation, or spectrum). Depending on the procedure, variations in the designated measurement quantity causes one or more of these properties to change, so that the returning signal is altered.
Fiber optic sensors can be divided into two main categories: extrinsic and intrinsic sensors. They differ both in design and function, featuring specific properties that make them suitable for different applications.
In intrinsic sensors, the light conductor is an essential component of the measurement mechanism. The optical fiber is the sensor. Common examples of this category include sensors based on Fiber Bragg Grating.
Extrinsic sensors, on the other hand, are characterized by the sensitive component being separate from the optical fiber. The optical fiber merely transmits the light signal between the sensor unit and the evaluation electronics. Examples of extrinsic sensors include temperature sensors based on gallium arsenide crystals (GaAs) as well as the WLPI-based fiber optic sensors presented below.
The signal evaluation unit feeds the light signal into the optical fiber, receives the reflected, altered signal, and processes it to output physical units of the measured quantity. The light source used can differ depending on the measuring procedure and technology.
Optical interferometry, which measures the phase modulation of light, is considered the most sensitive method of fiber optic measurement. An interferometer is a high-precision optical measurement device featuring two or more light beams that are guided on different paths through semi-transparent mirrors before being reflected and recombined by another set of mirrors. This results in an interference pattern which is determined by the difference between the optical paths taken by the individual beams before their recombination/superimposition.
Using interferometry lets you measure a physical quantity whenever variations in that quantity cause variations in the path length in the interferometer.
The lasers used as light sources in conventional fiber optic sensors led to issues with phase ambiguity due to their narrow bandwidth. This was due to the coherence length of the light source generally being larger than the difference in wavelength in the interferometer. As a result, possible applications for fiber optic sensors based on interferometry were limited. The solution to this problem lies in using a light source with a shorter coherence length and broader light spectrum.
This kind of interferometry is called white light interferometry or optical coherence tomography. The founders of Opsens are pioneers in white light interferometry for fiber optic measurements. They have refined this technology to commercial viability.
We offer standard fiber optical sensors but can also help you with a customized design or a complete measurement solution.
