Patent ID: 7426856
Filing Date: 2008-09-23
Classification: G01N

Abstract:
1. A method for measuring adhesion strength between a first optical element and a second optical element, the first optical element having a first surface and an opposite second surface, the second optical element being adhered to the first surface of first optical element, the second optical element defining an opening therein, whereby a portion of the first surface of the first optical element is exposed to an exterior, the method comprising the steps of: placing a first magnet on the exposed portion of the first surface of the first optical element and a second magnet on the second surface of the first optical element in such a manner that the first magnet and the second magnet are magnetically attached onto the first and second surfaces of the first optical element, wherein a magnetic force between the first magnet and the second magnet is greater than the adhesion strength between the first optical element and the second optical element; attaching the second magnet to a force gauge; attaching the second optical element to a fixture; exerting an increasing force onto the force gauge in a direction away from the second optical element until the first optical element is pulled off from the second optical element; and obtaining a measurement result of the force gauge, and then calculating the adhesion strength between the first and second optical elements based on the measurement result of the force gauge; and displaying the adhesion strength to a user.