Patent ID: 11867611
Assignee: OPTONOR AS
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 15:
16. A method of analysing an object, comprising:
exciting the object at a vibration frequency so as to induce a stationary or travelling wave, having the vibration frequency, on a surface of the object;
using optical interference to determine vibration phase data for each of a first plurality of points on the surface, the vibration phase data representing, for each point, a respective phase, relative to a common reference phase, of the stationary or travelling wave;
using optical interference to determine vibration amplitude data for each of a second plurality of points on the surface;
processing the vibration phase data and the vibration amplitude data to generate maximum-spatial-derivative-of-displacement data, representative of a respective maximum absolute value, over a time period, of a first-order or a second-order spatial derivative of surface displacement, for each of a third plurality of points on the surface; and
processing the maximum-spatial-derivative-of-displacement data to determine a property of the object, or outputting a graphical representation of the maximum-spatial-derivative-of-displacement data on a display device.