Introduction to Lens Processing Flashcards
What is a surfacing lab?
portion of the lab that creates the needed lens power
What is a finishing/edging lab? 3
portion of an optical lab that is reponsible for positioning, edge grinding, shaping of lenses for the frame chosen
What does a surfacing lab perform? 4
surface generating
fining
polishing
deblocking
What is the lens processing sequence for semifinished blanks? 3
1- Order Entry
2- Surfacing
3- Edging
What is the lens processing sequence for finished blanks? 2
1- Order Entry
2- Edging
What are the 3 categories of ophthalmic lenses?
1.Single Vision Lenses
2.Segmented Multifocal Lenses
3.Progressive Multifocal Lenses
What 4 ways are multifocals prepared for the finsihing lab?
*May be individually ground and polished to power
*May be individually cast molded to the prescribed power
*May be made by laminating front and back lens halves together
*May be kept as stock, finished bifocals
What is edging?
Edging is cutting the lens to the correct size to fit the frame
What is a lens blank?
A lens blank is a lens before it has been edged to fit into a frame.
What is a finished lens blank? 3
-already has correct powers in the front and back surface
-ready to use
-only needs to be edged
What is a semi-finished lens blank? 3
-only one side of the lens is finished
-normally front side is finished
-back side needs the power polished and ground in
What causes a coating crazing?
Heat
Flexure
Too much pressure
What do we do to the edge of a drilled rimless lenses when edging?
Keep it as a flat edge
