The " bite test " was to check if the coin was gold.

Use an ordinary hinge door hinge only rely on the bite force can not help the test of time, could be considered to spring, either to the inside or outside the door, you can open and close easily.

In the paper, the method of test about OE-PCB was reviewed. Including mainly Refractive Index, Optical Propagation Loss, Surface Roughness, Eye Pattern, Bite Error Rate test and Environment Impact.