Hi there - I'm not a medical practioner, AME or anything connected with the medical profession, just an ATPL holder of 20 years.
The AME should not need to see the prescription for your specs. - I've never been asked to produce one. As long as you can read the sight chart and pass all the tests at the examination, they should issue the certificate. It will be stamped with one of two things - must wear specs Or must wear specs AND carry a spare pair - it depends on the level of visual deficiency.
Contact lenses can be worn, but a spare pair of specs have to be carried in case the lenses are dropped and lost.
Tinted lenses, etc. are OK but don't work behind the windscreen of an aircraft due to the design of the windscreen.