Ask the Labs, Eyecare Business

If a patient has a high-plus or high-minus Rx, which frame characteristics should be taken into consideration to ensure it will work best with the lenses?

When working with a patient with a high-plus or high-minus lens Rx, say over four or five diopters in total power, the following tips can help:

In general, rounder and smaller shapes are best for reducing edge thickness. One key factor in reducing edge thickness is picking a frame that requires the least amount of decentration. Decentration is the natural enemy of high-power lenses, as decentration increases, so does edge thickness. Another way to look at it: The closer the geometric center of each eye is to the pupil, the less edge thickness there will be.

Of course, other aspects of frame choice also have a role to play. A frame that hides more of the lens edge will help improve aesthetics— with plus lenses the thickness will tend to be in the nasal, with minus lenses it will be the temple edge. Be careful with drills and rimless groove frames; instead consider zyl or metal frames with thicker eyewires.

As for wraps, they are designed for lower powers, typically from -3.00D to +3.00D, and can become risky above this range. For wraps in general, we strongly recommend consulting the frame manufacturer to determine the lens range the frames were designed to accommodate.

— Swen Carlson, vice president, operations, VSP Optics Group

A Look at Lens Materials by Jenean Carlton, ABOC, Eyecare Business

Given all the considerations of lens materials, how do you make a decision about the best lens material for your patients?  First, learn about the patient’s prescription and lifestyle needs and then research data about materials.

Index of Refraction: Index of refraction indicates how readily a lens material will refract a bean of light. The higher the index of refraction, the more the material will bend light rays. The higher the index of refraction, the thinner the lenses can be processed. Plus power lenses are thinner in the center when fabricated and minus lenses are thinner on the edges.

Abbe Value: White light is made up of the visible spectrum of wavelengths from 380nm to 760nm, with each wavelength corresponding to different colors of light. The higher the Abbe value of a material, the less likely it is to have problems with dispersion or chromatic aberration, which is perceived as color fringing or off axis blurring in the lens periphery.

Specific Gravity: Specific gravity is a measurement that determines a lens material’s weight. The lower the density or specific gravity of a material the lighter it will be when fabricated into a lens.

Reflectance: All lenses reflect at least a small percentage of light; some reflect a significant amount depending on the refractive index of the material. The higher the materials refractive index, the greater the percentage of light reflected from the lens surfaces. (END ARTICLE)

At Optical Dynamics, our clearLIGHT advantage lens combines the best of all attributes:

• Thin – Premium Index
• Light Weight – 1.20 g/cm3
• High ABBE Value = 40
• UVA & UVB Protection
• Exceeds FDA Standards
• Drillable
• Excellent Tint Absorption

Eyecare Business by Stephanie K. De Long

Tip #1 Be Visual & Verbal – Marketing and message have to take into consideration not just the age of kids but also whether your communication is meeting their learning styles. That’s often overlooked.

Tip #2 Understand the Essence – Whether you’re talking about a product, program, or promotion, this is an exercise that has proved very useful at Youth Market Systems in the development and marketing stages.

Tip #3 Consider Identification Patterns – Whether it’s a real person or – in terms of character identification – an animal or cartoonlike personality, you can understand identification patterns: how a child relates to and interacts with things and people.

Tip #4 One Size Won’t Fit All – Whether attempting to market through advertising, print, promotions, or the Internet, certain generalizations are often applied. Some work, Some definitely don’t.