11/28/2017

Versatility for laboratory and production – confocal and interferometric measurement technology in one

FRT offers the optimal solution for customers who need more than just confocal microscopy for their measuring tasks. Dual Technology “, or DT for short, these letters are intended to indicate the special strength of the versatile CFM DT surface sensor: the combination of a spinning disc confocal microscope (CFM) with a white light interferometer (WLI). This combination offers the advantages of both measuring methods. The very high vertical resolution in WLI mode and the high lateral resolution in CFM mode. This makes it possible to characterize both minimal and more structured samples, which either reflect less or strongly, in the same way – contactless, non-destructive and within a few seconds. For example, roughness, contour and 3D topography can be displayed with micro- and nanometer resolution. Due to its multi-functionality, this sensor is used in research and development as well as in production control in various industries.

With two measuring modes, the white light interferometer precisely determines the 3D topography of both minimally structured and highly structured surfaces. In both modes, the variable measuring field size without loss of resolution and the high measuring speed are convincing. Smooth sample surfaces such as lenses, glass or wafers are measured in interferometric phase shift mode. The height structures are typically measured with sub-nanometer resolution. The maximum vertical resolution is independent of the field of view and the aperture of the used objective. The method is able to capture a field of view of up to 7.1 mm x 5.3 mm in less than 10 seconds by gradually shifting the objective in axial direction by a part of the light wavelength. The generated interference images are then calculated to a 3D topography. This is the starting point for further high-precision geometric, roughness, volume and surface analysis on the measuring computer. In white light interferometry mode, the objective is also shifted in the height stepwise. However, the maximum interference contrast of the respective focal plane is evaluated so that, in contrast to phase shift interferometry, the method is also suitable for more structured surfaces. The basic advantages of interferometric measurement, such as the variable measuring range without loss of resolution and the high measuring speed, are fully preserved.

The integrated confocal microscope with its excellent depth of field allows light microscopic measurements in different resolutions. Thanks to its objective turret, you can quickly switch between different objectives with different zoom levels. The turret can be equipped with up to six objectives at the same time and allows a very flexible use. Depending on the requirements, criteria such as a long working distance with a long distance objective can be fulfilled. This is simply screwed into the integrated objective turret and can be selected quickly and comfortable by simply rotating it. Thanks to the integrated stitching function, even large samples can be precisely measured. The resolution and measurement capabilities can be further enhanced by using an atomic force microscope (AFM) instead of a normal objective.

The CFM DT can be integrated into all multi-sensor tools of the established MicroProf® series. The degree of automation goes from manually operated measuring systems such as the MicroProf® 300, which automatically execute pre-defined programs, to fully automated handling including automatic pre- and fine alignment in the MicroProf® MHU. The CFM DT is also available in the single-sensor tool MicroSpy® Topo DT.

We certainly have a solution for your specific task. Do not hesitate to contact us if you have any questions. Our experts will be glad to take care of your needs and work out individual solutions for you.