Instron Limited

Illinois Tool Works Inc.

David W Long

Paul D Hayford

A method of monitoring the surface of a sample under test is provided and the method comprises the steps of: illuminating the surface with light () polarised in a first direction; viewing light reflected from the surface through a polarising filter () arranged at 90&#xb0; to the first direction, wherein the surface of the sample under test is provided with a marked area where diffuse reflection of the incident polarised light will occur in order to improve the contrast between the marked area and the surface of the sample under text.

Testing of samples

Test apparatus comprising means for holding a sample to be tested, means for altering the strain in the sample, an optical arrangement for monitoring the sample to be tested, and processing means for processing the signals resulting from the monitoring of the sample under test, wherein the environment between the optical arrangement and the sample under test is controlled, and wherein the sample to be tested is located in a position external to the controlled environment.

Growing community of inventors

Tring, United Kingdom

David W Long