Assembling transparent articles, eg solar cell covers, by use of markings

摘要

To facilitate correct orientation of a solar cell cover 2 to locate its coated face 3 away from the solar cell member 1 with which it is assembled, its other face is provided with an orientation indicative surface relief mark 6 which becomes invisible when the cover 2 is secured to the member 1 by an adhesive 4 of matching refractive index.