Further progress in the absolute orientation determination of doubly rotated quartz blanks by means of the Ω-scan method

The extension of the X-ray Ω-Scan Method for doubly rotated quartz blanks to a larger orientation range and the correction of systematic errors are described. Now, the method is applicable to a range of 33 to 35 (Θ) and 14° to 24.5° (Φ) including IT-cut and FC-cut material. Under certain conditions the measurement of IT-cut blanks may be ambiguous with reference to the value. Systematic errors due to uncertainties in the exact peak determination can be corrected by means of simulation calculations of the intensity distributions taking into account the individual geometry (tube focus, collimator) and dead time of the detecting system of a machine as well as the peak intensity of each reflection. The correction procedure is implemented in the evaluation software of the sorting machines. There result true absolute values of the orientation parameters. The differences to uncorrected values may amount up to 1 arcminute in Θ