How Eyeglass Lenses are made

by Bruno Carissimi Bruno Carissimi Lens Processing Technologies will

Have you ever wondered how eyeglass lenses are changed from a piece of glass into something that can make you see better? For centuries humans have been using lenses to correct bad vision but the way lenses are created has thankfully improved which means better vision for all of us.

Just like starting a painting with a blank canvas, in a similar way each time a new set of glasses is made they start with a lens blank. And even though lenses start out looking like a big thick glass coaster, they are actually made of plastic resins. Each type of lens has a different curvature surface, so whether it is a bifocal, trifocal or a progressive lens the curves of the resin vary.

The first step in preparing the lens for those spiffy new frames you just picked out is called surfacing. This is a process in which the frosted looking lens is polished up so it is completely clear. When the coaster sized lens comes off the manufacturer’s floor it has a frosted appearance to it. A technician uses a fine grit pad like very fine sand paper attached to a precisely tooled polishing block to smooth the surface of the lens. Once the resin is clear it is on to the next step.

Since the lens was sanded down it is a bit thinner than it started out, but this next step really cuts it down to size. A computer is used to precisely cut the lens so it fits right into those new frames. The edger passes the lens over a diamond cutting wheel until it is reduced to the right size and shape.

The lenses are almost done but they still need a few finishing touches, like the topping on a perfect ice cream cone, these finishing touches make the glasses even better! The lenses can be specially coated to resist scratching, to block ultraviolet light or to reduce reflections. This can help those kids who drop their glasses while playing ball, and can protect your precious eyes from the sun. The reflection reducer helps with those long hours on the computers we all love to sit in front of.

So that is how lenses are made in a nutshell! There are always new technologies being integrated into the lens making process, and some of the advances in LASIK surgeries are changing the way lenses are made. For more information regarding Lens Processing Technologies please visit www.brunocarissimi.com.