The manufacturer’s current method for detecting defects required an operator to evaluate an image projected onto a wall with an overhead proje
Defects appear as bright spots
MicroCraft re-conducted the manufacturer’s original test procedure using a cross-polarized light fieldCONTROL ENGINEERING China版权所有, along with vision and motion systems. In this method, distortion of the aligned polymer chains in the material made defects appear as bright spots. A two-step analysis was then conducted using two cameras—ones with large and small fields of view (LFOV and SFOV, respectively) and different magnifications (LFOV: 0.3XCONTROL ENGINEERING China版权所有, SFOV: 6.4X). The LFOV camera was used for initial film inspection to find defects. Operators used the SFOV camera for secondary defection evaluationCONTROL ENGINEERING China版权所有, and to capture images and measurements for data storage.
A backlight table was covered with a polarizing sheet and placed on a 2-axis linear rail system to control the lighting and motion of the manufacturer's 8-in. diameter samples. Motion, vision, and data collection were combined using a National Instruments PXI-7324 motion board and two PXI