Patent 9600694 was granted and assigned to Apple (company) on March, 2017 by the United States Patent and Trademark Office.
A manufacturing method for sapphire crystal material is disclosed, including a laser-etched bar code formed into the interior of the sapphire crystal material. The laser-etched bar code may be associated with one or more manufacturing parameters or other manufacturing data. The sapphire crystal may be used to create a cover sheet for use with a display screen of a portable electronic device.