Application areas
Production of high quality transparent plastic items
In addition to checking for defects, a measurement, test or control of the stresses in the material can be carried out.
Control of stresses in glasses
If, in addition to checking for defects, a measurement, test or control of the tension in the material is to be carried out.
Controlling the annealing of transparent articles
With the scanner, the achievement of a maximum target tension pattern can be detected and achieved directly.
Glass production
The optical measurement of the pull-off force allows direct force control.
Specifications
Specimen
- Transparent (transmission > 10%) clear or colored articles
- Diameter < 150mm
Principle
Imaging telecentric retroreflex laser scanners with polarization option
Measurements
The scanners provide images at their image interface (just like line scan cameras) from which the following variables can be determined:
- Defect sizes
- Tension pattern
- Birefringence (when the optical path length through the material is known)
- Pull-off force (if the path length through the material and the stress-optical coefficient of the material are known)
Resolution
- Depending on scanner type and material
- For glass tubes a resolution of phase differences of 0.1 nm has been achieved
Measuring area
160(W) x 100mm(D)
Laser class
3R
Components
- Combined transmitter / receiver unit (emits the laser beam)
- Retroreflector (behind the test object)
- 24V supply unit (power pack or supply unit with integrated PC)
Particularities
- Robust against object displacement
- Minimum effort for adjustment
Interfaces
- Image interface (GiG-E or CameraLink)
- RS-232 interface for parameter setting
Software
OPOS Scanner Player (OSP) for acquiring images and configuring the scanners. A complete evaluation software (Purity) with production line interface is available from our partner Fraunhofer IOSB.
Application examples
The figures below show the characteristics of the measurement of the pull-off force, which was recorded with the Purity software from Fraunhofer IOSB on a glass tube with a diameter of 30 mm and a wall thickness of 3 mm in the sketched test setup. A standard deviation of the pull-off force of <0.5 N was achieved
In the images, interference effects such as stress patterns or stress waves in the material, for example when pipes are cut, can be directly observed (see image below left). A minimization and thus optimization of the production process can be directly observed. At the same time, defects in the material can be displayed directly and recognized automatically (see figure on the right).
Send us your samples for a first free test or let us convince you with a device demonstration in your house!
We would be adapt to adapt our sensors to your application or develop new functions for you.
Patents
- M. Hartrumpf, "Laserscanner-Meßsystem"; DE19806288A1
- M. Hartrumpf, "LASER SCANNER MEASUREMENT SYSTEM"; EP1056987A1
- M. Hartrumpf, "Laser Scanner Measurement System"; US6858836B1
- M. Hartrumpf, "Vorrichtung und Verfahren zur optischen Charakterisierung von Materialien": EP11760701.0
- M. Hartrumpf, "Apparatus and method for optically characterizing materials": US9222879B2