Possible Clues:

• Where "E" is a line
• Exam material you really wouldn't want to memorize
• It's read at the opticians
• It may end in PEZOLCFTD
• Examination taken by an E-reader?
• Where you may need to read the fine print
• Lines of sight?
• Where ''E'' is a line
• It may be used to find out if you have good contacts
• It begins with an E (in two ways)