My Little Buddy: The Prism Reference Point

By Johnna Dukes, ABOC
Monday, August 31, 2015 12:11 PM

I love manual lensometry. If a fire were to suddenly threaten my boutique, I would grab my favorite vintage specs that belonged to my great-great aunt and my manual lensometer and then I would run for my life.

Trivex Material, Still a New and Growing Lens Category

By Mark Mattison-Shupnick, ABOM
Tuesday, July 28, 2015 7:35 PM Frame choice also drives material choice. Usually the patient will select their frames first and then the lenses. This can present a problem with some lens materials. Consider the combination of a plus lens and a grooved semi-rimless frame.

Trivex Material, Still a New and Growing Lens Category

By Mark Mattison-Shupnick, ABOM
Wednesday, July 15, 2015 10:11 AM When compared to CR-39 monomer, lenses made with Trivex material are up to 15 to 20 percent thinner and always about a third lighter. An aspheric design will further reduce thickness and weight. While there are other higher index materials that can make lenses even thinner, lightness depends on final lens volume and its specific gravity.

Trivex Material, Still a New and Growing Lens Category

By Mark Mattison-Shupnick, ABOM
Wednesday, July 1, 2015 10:10 AM

Trivex material’s development has been consistent with the way new technologies build sophistication into products. In the past, a lens material had to be more closely matched with the prescription and the end results wanted. This is no longer the case.

How Do You Know Your Lens Is The Right Power? (Part Three)

By Dick Whitney – Carl Zeiss Vision
Executive Director – Optical Heritage Museum
Chair of ANSI Z80.1 and the Vision Council Lens Technical Committee

Wednesday, June 10, 2015 10:05 AM I was fortunate to have access to the NBS 1916 calibration set, from which I was able to make my own secondary set, which I still use today. Since I had confidence in their powers, it has proved especially useful. What does one do if there is a need to assess an instrument but one does not have such a set?

How Do You Know Your Lens Is The Right Power? (Part Two)

By Dick Whitney – Carl Zeiss Vision
Executive Director – Optical Heritage Museum
Chair of ANSI Z80.1 and the Vision Council Lens Technical Committee

Wednesday, May 27, 2015 1:07 PM In Part One of this three-part series, I described the history and early use the American Optical (AO) “NBS Truepower lens set” developed in 1916, which was used to assess the calibration of the AO Lensometer when first introduced to the market.

How Do You Know Your Lens Is The Right Power? (Part One)

By Dick Whitney – Carl Zeiss Vision
Executive Director – Optical Heritage Museum
Chair of ANSI Z80.1 and Vision Council Lens Technical Committee

Tuesday, May 12, 2015 3:00 PM I was recently asked what I thought was the most valuable item in the Optical Heritage Museum collection.

Handle With Care: Tips for Preparation of High Power Prescriptions

By Johnna Dukes, ABOC, FNAO
Monday, August 6, 2012 5:18 PM Quick, what comes to your mind when the patient in front of you hands you this prescription, -13.00D sph O.U.?

The Lens Formula

By Staff
Monday, November 21, 2011 11:05 PM The prescription, or lens formula, is the starting point for picking the best lens material, frames, and eye and bridge size.

The Prescription and Vision

By Staff
Wednesday, November 9, 2011 10:48 PM It starts with the prescription. The prescription (Rx)describes the patient's Refractive Error. Any Prism needed for the eyes to work together and an Add if needed for near vision/reading.

Power at any Meridian

By Staff
Wednesday, November 2, 2011 4:38 AM So far we've learned the power at each of the principal meridians, the axis and 90 degrees from the axis. What happens in between?

Tips: Lens Appearance

By Staff
Wednesday, November 2, 2011 4:03 AM Here are some quick tips to be sure that the lens is returned from your lab as you expected - the last thing we want is a surprise...
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