Thickness measurement of transparent and thin foils

When recycled plastic is processed into a plastic foil through an extrusion process, this foil needs be finished. The end customer often has different requirements. One of the requirements is the correct thickness. To finish the plastic into a desired end product, the foil thus needs to be stretched.

Stretching

With stretching, the main material of the foil is stretched until the desired thickness is achieved. A thickness measurement of foils is crucial to evaluate the production process and eliminate errors.

Thickness measurement with the SPECTRO-MIR-10

Sensor Instruments offers SPECTRO-MIR-10 infrared sensors to measure the correct thickness. This enables thickness measurement of films both during the production process (inline) and outside it (offline). The sensor uses infrared light MIR (Medium Infrared Range) within a specific wavelength.

To determine the thickness (zero point measurement), the sensor emits the infrared light on a metal plate. In addition to emitting light, the sensor is also capable of receiving with two detectors. One detector determines the reference value. The other receives the light that is reflected from the foil or the metallic background.

The thickness of the foil is determined by the difference in measurement between the reference value and the actual measured value. The desired foil thickness can be configured through provided software. In addition to this, it is possible to set treshold values to the measurement of the foils. Production errors are recognised in time and removed from the batch. This way the quality will be constantly monitored.

Also curious about the possibilities with oil? Consider a thickness measurement of oil with infrared sensors.