How to Grind Lenses for Eyeglasses

Optical lenses start out as a chunk of plastic called a lens blank. Grinding is the process of putting a specific prescription in the lens. The process used to be done by hand and only in large optical laboratories. Computer technology has made grinding lenses much easier. Machines that cut lenses are available with varying styles and technology. According to Eyecare Business Magazine, surfacing or finishing machines can cost from $10,000 to $60,000 or more. Even with computerized machines, you must do several basic steps when grinding lenses.

Things You'll Need

• Finishing machine
• Blocks
• Blocker
• Lens blanks
• Pattern
• Grease pencil

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Instructions

• 1

  Familiarize yourself with the surfacing machine you are using. Read the manual to help understand the specifics of each process of grinding the lenses. Because each manufacturer designs their machines with unique characteristics for each step, be sure to review the process for the machine. Lay out the lenses, right and left.

• 2

  Mark the right lens blank with an "R" and the left lens blank with an "L" with your grease pencil.

• 3

  Attach the adhesive pads and blocks to the front of the lens blanks. Apply the blocks manually, or use a tool called a "blocker" if you are grinding multiple lenses. Most labs use blockers during the grinding process when many lenses are being processed.

• 4

  Place the blocked lenses in the machine according to the manufacturer's protocol. Close any shields or doors and set the parameters and required information for the lens prescription, again according to the specific directions for the machine you are using.

• 5

  Remove the lenses when the machine has completed the grinding process.