Technologies
Confocal Chromatic
Chromatic confocal technology
Chromatic Confocal Technology for 3D optical distance and thickness measurement has been adopted as a proven method in industry and research. It is a perfect complement to traditional optics for in-plane measurement.
Chromatic confocal technology enables reliable, accurate and dimensionally repeatable measurements in high definition. It is particularly suitable for transparent materials such as glass.
qmt has a complete research equipment and offers studies and advice in particular in the field of quality control.
Principle of operation of a confocal chromatic sensor
Image and information provided by Precitec (precitec.de)
The confocal chromatic measurement principle is based on polychromatic light which is classified into different spectral colors by being focused by a multiple lens optical system at varying distances from the sensor. More than long wave red light (700 nm), short wave blue light (400 nm) is refracted. The start of the measuring range is with blue light, while the end is with red light. Each wavelength is in a different focal plane due to controlled chromatic aberration. Each wavelength is assigned with a specific distance to the target by factory calibration. In the case of a sensor system, this wavelength of light is used for the measurement which is precisely focused on the target. The light which is reflected is reproduced by an optical device on a light sensitive sensor element, on which the corresponding spectral color is detected and evaluated. Some of this light is reflected with each change of refractive index of different materials, making it possible to measure the thickness of transparent materials, even on one side. In multi-peak measurements, a number of distance points are evaluated.
