New PD Ruler design is in big demand.

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A new design for the PD ruler (Pupilary Distance ruler) has received an impressive response from eye care professionals who have had access to it. Optical shops that tried out the ruler noted a significant decrease in symmetrical PD measurements, and found the new design to work easier, faster, and safer than traditional PD rulers.

ADS Eyewear handed out the first 1,000 prototypes of this new ruler to opticians in New York and Texas. Since this initial promotion in March, they have been scrambling to keep up with demand.

Given the name "Perfect PD Ruler" by the inventors, the device is simple, inexpensive, and uniquely designed for a single purpose. There is a bridge in the center of the ruler to hold it stationary and centered on the patient's face. The measuring scale has zero marked in the center and measures outward to each pupil. And the corners are rounded to minimize the risk of eye injury to patients.

The most dramatic result reported by optical shops using the Perfect PD Ruler was a sharp drop in symmetrical PD measurements. ADS Eyewear is currently working on converting these initial impressions into actual statistics. Most opticians attributed this drop to the bridge in the center of the ruler. By making the center-point less subjective, monocular PD measurements were more accurate.

David DuMais, who created the "Perfect PD Ruler", says children were the original inspiration behind his invention. After purchasing standard metal PD Rulers he cringed at the thought of anyone using them near fidgety children. Says Mr. DuMais: "It takes a steady hand and a steady patient to get an accurate PD measurement. But holding a sharp metal corner close to an energetic child's eyes created even more anxiety than getting an errant PD measurement."

ADS Eyewear has applied for a patent on this design, and expects final approval from The United Stated Patent and Trademark Office by the third quarter of 2006. Currently all sales of the ruler have been through their web site, The Perfect PD Rulers are also available with custom printing for companies that use them as a promotional item. ADS Eyewear can be reached at (877) 597-3667.


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David Dumais