The lens demonstrations in Essilor’s Visioffice help patients understand the benefits of a variety of lens options.
Proper patient positioning is easy with Optikam’s EY-Stick, which enables patients to assume their natural body posture for proper alignment.
To save time and keep the experience simple, consider a patient’s individual needs when deciding which features of a measuring device to use.
Carl Zeiss Vision’s i.Terminal 2 captures several values in one image, including frame data, PD, mono PD, fitting height, segment height, BVD, PA, wrap angle, head rotation, and lens stamp.

Take these suggestions to heart for a successful experience with digital measuring and fitting devices.

Digital measuring and fitting devices generally offer a frame try-on function and demonstration of lens add-ons. While those functions may be the most dazzling to the patient, the measuring abilities of the instruments can be the most beneficial to the dispenser.

Most of these units, such as the Optikam EY-Stick, Essilor of America, Inc.’s Visioffice 2, and Carl Zeiss Vision, Inc.’s i.Terminal 2, can provide precise measurements, including segment heights, monocular PDs, lens vertex, frame tilt and wrap, and more. This data can be translated into lenses that provide superior vision and comfort, and take full advantage of the precision of free-form technology. But what happens when that goal isn’t achieved? Final results are only as good as the expertise you have in using the equipment. While these devices are highly capable, you’re guaranteed the best results when you use them properly. Follow these tips and you’ll be in good shape!

When using any of these measuring tools, the frame must be fitted to the patient before taking the “picture.” That means making sure the frame is secure, level, and at a wearing position the patient is comfortable with. Simply deciding on a frame and putting it on the patient before measuring just won’t cut it. Dispensers must take the short time needed to make sure the frame is completely aligned and at a position as it will be when the patient wears it. Remember, they may prefer the frame to sit lower or higher than the fitter might like, and that’s how they will wear the final product.

So what happens when you don’t do that? Well, the instrument will still take the images, but the final result will be flawed and all of those high-tech position-of-wear measurements will be skewed. That’s a disaster in the making, especially if you’ve spent time telling the patient just how great these lenses are going to be. Your “wow” factor will go out the window!

Perhaps you’ve spent some significant money purchasing one of these devices but you don’t have total faith in its ability to take more accurate measurements than you can get yourself. In some dispensaries, ECPs don’t fully trust the information provided by the measuring device and simply use it as a frame try-on unit. Are you backtracking to manually verify the results? What were you using previously? A Sharpie pen? A segment height gauge? A PD ruler? We know these tools can be valuable, but think about some of the other tools you will need for ordering many of the most sophisticated lens designs. For position-of-wear measurements you will also need a panorameter to accurately measure frame wrap, a distometer for wearing vertex distance, and a protractor, or a specialized tool for measuring pantoscopic and/or retroscopic tilt. That’s a lot of additional measuring and switching from tool to tool! When you do that, you’re missing out on some of the most valuable features of these devices. Didn’t you buy the electronic measuring device to accomplish these tasks as well as the basic ones? So why go back to confirm the results manually? You have to trust your instrument. Isn’t that what you paid for?


You have to admit that the demonstrations available on all of these units are pretty impressive. The demo feature can show the patient what their lenses will look like with, and without, photochromic options, polarization, gradient and solid tints, AR treatments, and progressive addition lenses vs. lined multifocals. Patients can fall in love with the technology and may not want to stop using it. But does every patient need all of those demos?

Sure, you’re excited about the technology and what it can do but you need to triage a bit when it comes to patient needs. Your presentation can become unnecessarily long if you use all of the features on every patient so it can pay to be selective in what you show them. First of all, the patient may become overwhelmed by so much input. Yes, those demos do help in showing premium add-ons and other features, but if your patient has insurance constraints or pre-identified budget issues or is not interested in colored contact lenses, you may be spending a lot of time for little (if any) return. Using every screen a device offers on every patient will get your dispensary backed up in no time.

You have the frame pre-adjusted to the patient’s satisfaction and now you have to ensure that he is in a comfortable and natural posture in front of the instrument. Make sure he understands that this is not a studio portrait pose but rather the way he positions his head naturally. Don’t attempt to modify the patient’s natural posture. Make sure the instrument is positioned directly in front of the patient. Many of these devices will give an error message if the image is going to be set too high or too low or simply out of range. Parallax can also be a problem when a patient has a habitual head tilt and that must be accounted for. Virtually all manufacturers of these devices provide intense training with the initial installation but some ECPs engage in shortcutting. Don’t do it!


Many ECPs forget about free-form lens designs when it comes to single vision lenses but those wearers can benefit from this technology, too. They will also need those complex position-of-wear measurements. Think about high Rx’s or moderate-to-high cylinders. Substantial lens aberrations can be eliminated by using the more sophisticated lens designs coupled with accurate measurements. One function of many of these devices is an accurate fitting vertex and lens tilt measurements. Those two alone can make a major difference in visual acuity and comfort for single vision lens patients with difficult prescriptions.

No single rule of thumb guarantees success with digital measuring and fitting devices, but with some thought and planning, you can absolutely increase your odds of making these devices work to their highest potential for your patients’ and practice’s needs.

Sharon Leonard is a licensed optician and contact lens practitioner in the Syracuse, NY, area.

ACCURACY ABOVE ALL Some ECPs question the need for so much accuracy when most patients are examined for prescription with a phoropter that is almost never in the patient’s position-of-wear. But when using these measuring devices, the result will be a compensated power that will help to eliminate most aberrations that disturb vision. Most phoropters are accurate to within 0.12D and do not take into account lens tilt or wrap. They are usually adjusted for PD and vertex, but many refractionists don’t include that information as a part of the Rx.


Carl Zeiss Vision Inc.
800-358-8258 •

Essilor of America, Inc.

800-542-5668 •

Optikam Tech, Inc.
888-356-3311 •


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