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J. Eur. Opt. Society-Rapid Publ. 21, 22( 2025)
Figure 12. Laser induced heating of etched sample and sample with USP-laser structured surface.
Figure 13. Laser induced heating( 500 W for 30 s) of glass materials SF6, ULE and Zerodur.
Figure
14. Stress measurement after laser heating of Zerodur, ULE, SF6, visualization of the optical path difference in nm / cm.
of 150 ° C. For example, for the polished surface, a deviation from the correct e of 0.7 to the value of 1.0 causes a deviation of the measured temperature of about 30 K from the target value.
Because of this, the contactless thermography method is rather difficult to apply for absolute measurement of temperatures, unless it is calibrated for the exact measurement approach, temperature range and sample surface properties.
6 Additional investigations with regard to the application in a laser-assisted grinding process
To exclude possible heating effects caused by the laser due to surface contaminants, the experiments were additionally performed on a sample that had been etched for 72 h at 60 ° C with a 30 % KOH solution and also a before polished