Testing of samples
AssigneeInstron Corporation
InventorsPaul Hayford, David Long
Life of this patent
Estimating the term…
Abstract
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 (20) polarised in a first direction; viewing light reflected from the surface through a polarising filter (27) arranged at 90° 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.
Claims8
A method of monitoring the surface of a sample (11) under test comprising the steps of:
- preparing a sample (11) with a reflective surface;
- illuminating the surface with light (20) polarised in a first direction;
- viewing light reflected from the surface through a polarising filter (27) arranged at 90° 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.
A system for monitoring the surface of a sample comprising:
- a sample (11) with a reflective surface;
- means (10) for holding the sample;
- means for altering the strain in the sample;
- means (22) for illuminating the surface with light;
- a first polarising filter (25) for polarising the light in a first direction;
- an optical arrangement (12) for monitoring the surface of the sample;
- and
- a second polarising filter (27) disposed in front of the optical arrangement and oriented such that its direction of polarisation is 90° to the first direction, wherein the surface of the sample comprises a marked area arranged to cause diffused reflection of incident polarised light in order to improve the contrast between the marked area and the surface of the sample.
Dependencies are inferred from the claim text.