Laserscan

The Sirolan Laserscan™ instrument, which measures individual fiber snippets by laser was developed by CSIRO, an Australian company. It accurately measures a number of fiber traits, including:

• mean fiber diameter (in microns)
• coefficient of variation of diameter (per cent)
• a diameter distribution histogram (per cent of fibers in 1-micron class intervals)
• fiber curvature in degrees/mm
• comfort factor (per cent of fibers less than 30.5 microns for wool).

The Laserscan has full international Wool Textile Organisation Test Methods status (IWTO-12-00), meaning that results may be certified and applied in wool trading.

Similar to the OFDA 100, samples must be cut into approximately 2 mm snippets before being entered into the machine. These snippets of fiber are then suspended in a solution in a glass container and scanned by a laser to determine the various measurements.

Reports generated by the Laserscan and OFDA 100 are similar, and numerous authors have concluded that results from the two methods are roughly equivalent. Interestingly, however, as of 2000 the The Australian Wool Testing Authority had determined to utilize the Laserscan as the method of choice.

Over the last 18 months AWTA Ltd has evaluated both the CSIRO developed SIROLAN/LASERSCAN and the competing Optical Fibre Diameter Analyser (OFDA) instruments.

Following its evaluation AWTA Ltd chose the SIROLAN/LASERSCAN rather than alternative technologies because:

• it has superior precision;
• it correlates closely with Airflow values;
• there is no bias over the range of diameters normally encountered in Australian wool;
• it is not affected by curvature;
• one calibration system can be used for both raw wool and for sliver; and
• it has greater potential for automation.

Like the OFDA 100, the Laserscan methodology is most applicable to larger scale processing, such as core testing of baled fibers, where they can be used to verify the grade claimed for the bale.