Wednesday, April 16, 2014 2:00 PM
A few weeks back a pleasant gentleman in his 60s was in our office and delivered to my dispensing table. We chatted about his prescription and when he wears his glasses most. He then pulled out his current glasses and they were a circa 1970 gold metal, modified aviator with a unifit bridge in a 59 eye size. As soon as his glasses were in my hand I realized—these lenses are glass, and very heavy indeed. Immediately I began thinking how happy he would be in his new polycarbonate lenses in a new smaller frame. Quickly I discovered my plan was not his plan. He explained he liked his frame and might even like a larger size. I decided to work on the frame first and then discuss the lenses. I showed him some metal frames in a 54 and 56 eye size as I explained patients often believe they have more viewing area when they have a large lens—but actually it was like walking up to a window or looking through a keyhole.
Tuesday, February 18, 2014 1:00 PM
The most common way of correcting vertical imbalance is to induce a
vertical prismatic effect in the lower half of one lens. This type of
correction is referred to as bi-centric grinding, or slab-off.
Tuesday, February 11, 2014 3:10 PM
"I follow ANSI Standards when inspecting mounted lenses prior to dispensing."
Monday, February 03, 2014 10:30 AM
There are two ways basic ways to verify slab-off: Comparing the vertical prismatic effects of the two lenses
through a lensometer and checking for actual image displacement at the reading level.
Tuesday, December 03, 2013 3:51 PM
First, it is an effect of the prescription as determined by the doctor,
so we cannot fix it, but we can correct for it. Some methods are capable
of correcting for more imbalance than others.
Sunday, November 24, 2013 10:00 AM
According to “The Dictionary of Ophthalmic Optics” (Keeney, Hagman,
& Fratello), Anisometropia is defined as, “Unequal refractive errors
in the two eyes.”
Tuesday, November 19, 2013 1:00 PM
Powered lenses are, in effect, prisms either mounted base to base (plus lenses), or apex to apex (minus lenses).
Wednesday, October 16, 2013 11:00 AM
Children waiting in line get on an amusement park ride dread the sign
that says "You Must Be This Tall to Ride." Particles of light (photons)
on their way to break a molecular bond run into a similar problem.
Wednesday, September 18, 2013 6:29 PM
Digital can be a wonderful tool and in his interactive book on Lensometry, Mark Bullimore, MCOptom, PhD, FAAO brings learning the Lensometer to life through interactive video and an embedded glossary.
Wednesday, August 14, 2013 5:26 PM
An optician, a nurse, and a pharmacist are competing in a reality show. A coffee thermos is left floating just offshore from the beach and the first one to reach it gets a hot cup of coffee.
Tuesday, July 23, 2013 2:00 PM
When I am on a plane, in an airport or at a dinner and people ask me what I do, I respond by saying, "I bend light and count molecules for a living." This is a pretty grand statement and most times I am proud of the complex, medically beneficial science that I am in.
Monday, July 15, 2013 12:00 PM
Everyone knows human eyesight is variable in nature. Whether it be yearly, weekly or hourly—vision is fluid.
Friday, May 24, 2013 6:23 PM
"Is that mirror a Flash or a Dielectric?" "All bright mirrors are metal mirrors." Have you heard these or maybe said them yourself?
Wednesday, May 08, 2013 4:37 PM
I have had many conversations through the years regarding Cracking and Crazing of AR coating, and what causes each. In this article, I want to discuss several of the things that lead to Cracking and Crazing in an effort to understand the relationship between the lens, the layers of the coating and the coating as a whole.
Tuesday, March 12, 2013 5:53 PM
Base curves, we've learned are an effective way to provide adequate vision, over the entire lens, for a range of sphere and cylinder prescriptions.