Fitting and Delivery
08-2008
 Fitting – Fitting eyewear requires practice since the number of possible combinations of head and frame sizes and shapes is enormous. Therefore, the more that it is done, the easier it gets. There are, however, some good rules to use to get the best fit. First, eyewear balances on three points, “the three point triangle.” Therefore, the fit on the nose and at the crest of each of the ears are the places to be scrutinized to be sure that the frame chosen fits right. Does the bridge fit? The more area that touches, the better the frame will be supported. For adjustable nose pads, are they large enough, can they be adjusted to sit flatly on the surface and not dig into the skin? In a saddle bridge, do the pads sit on the nose or does the frame only rest on the top of the nose?  When possible, choose frames that locate the eye close to the geometric center of the frame opening. This reduces the need for excessive lens decentration. It also reduces a “too narrow” look of the eyes in the frame. In a larger frame, dark frame colors will accentuate a narrow PD, lighter frame colors can help if there is lots of decentration. For large sunwear, there will more decentration required, reduce lens thickness effects by using higher index lens materials. Of course, the eye is hidden behind the dark lens so accentuating a narrow PD is not usually a problem. Ensure that there is enough lens in all the viewing areas that are important for this prescription. For example, a large aviator on a narrow PD may not provide enough reading area for a progressive. The lens shape may cut away most of the reading. Choose a smaller modified aviator when possible to meet the patient’s want and their need for good reading. For sunwear, is there good coverage, and will the frame block glare in all directions? Temples should be long enough to be bent at 45 degrees at the crest of the ear and extend about 40mm behind the ear. Too short a temple may not be comfortable and may not provide the right fit. Too long a temple is less of a problem if it remains hidden behind the ear or can be shortened (easier on metal temples). Capitalize upon the brand recognition and the millions of dollars spent each year by well known fashion houses on advertising and marketing. Grouping branded eyewear together and presenting it under its specific logo creates brand “critical mass.” Learn how each brand’s logo helps to define and re-enforce associations with particular lifestyles or usage. Use this knowledge to help your clients find the sport, dress, casual, work or fun styles they’re seeking.
Barry Santini, ABOM
Long Island Opticians
Seaford, NY
What Would You DO?
PATIENT SITUATION
Mrs. Diaz has a prescription for multifocals. The new
distance PD measurements are below. Her previous PD
was 30.0/31.5. She has decided to purchase a pair of
progressives for general wear. What are the fitting measurements
that should be ordered and how will you verify
the lenses when you receive them back from the lab?
SOLUTION
Order exactly as you have measured. Order the distance
monocular PD as R30.5/L31.5. Use the new values since
you checked them twice (right?) and we know that as
people age, their PD does get wider. Dissimilar fitting
heights are also required and should be ordered as
R18.5/L17.0. This is especially important for small frame,
short corridor lenses since lens powers change quickly as
the eye rotates down through the lenses. Dissimilar
heights ensure that each eye sees the same power.
Delivery
Delivering a frame to a patient that, not only fits great, but looks great is key to exceeding a patients’/consumers’ expectations.
Bench alignment – A frame should be bench aligned before delivery to the patient. It makes the frame look exact and precise because it is straight and symmetrical. Also, be sure that the lenses have been cleaned of all fingerprints. There are seven steps to perfect bench alignment.
- Looking at the front, straighten the bridge so the two eyewires are aligned; from the bottom, be sure they are not propeller-ed. For metal or plastic frames, bend the bridge. For rimless, use two bracing pliers.
- Give the frame a slight face form bend.
- Next, be sure that none of the eye-wires are misshapen or rolled (happens on an overly heated plastic frame during glazing)— if a plastic eyewire is rolled, soften the eyewire, remove the lens, heat the eyewire again and roll the eyewire back into shape, re-insert the lens.
- Viewing from the bottom, make the temples near parallel.
- From the side, confirm that the temples have the same tilt angle to the front. Test for tilt with the frame upside down. Both temple tops touch the table at the same time, “a four point touch.” If not, adjust the angle so they are parallel.
- Next, confirm that the angle of the temple tips is the same. Place frame right side up. Temple ends are at the same angle when both touch the table at the same time. If not, adjust as needed and test again.
 Last, when closed, the temples should overlap each other. This confirms that the frame is completely symmetrical. To adjust metal frames, close the temples, use a narrow plier and move the temples until they are over each other. Be sure that the endpieces are also in line.
Basic Frame Fitting Tips – Place the glasses on the patient for steps one and two. This keeps you in control and speeds the adjusting process. For three and four, ask the patient to put them on. This ensures that they will be where they are going to be worn and that helps adjusting for straightness and temple fit.
- Place the frame on the patient and adjust for slight temple tension without indenting the head. For plastic, heat the endpieces or bridge slightly and open the angle, let it cool and try again. For metals use pliers and be sure that they are covered so as to not mar the frame finish. For rimless, use a bracing and post/covered plier.
- Raise or lower the temples to adjust pantoscopic angle. About 10 degrees is right. Use a wide angling plier or parallel jaw pliers. For some frames pliers may be required to stabilize the front while the temples are bent up or down.
- Straighten the front by adjusting for different ear heights. To raise the right side of the frame, lower or increase the pantoscopic angle of the right temple (lowering the temple raises the front of the frame on that side). For plastic, open temple slightly and angle the hinge. For metal, brace the front and angle the endpiece using a wide angling or parallel jaw plier. For rimless, a bracing and double covered plier.
- Ask the patient to put the glasses on. Adjust temple length to the ear. Create about a 45 degree angle at the crest of the ear. If the temple bend is too short, the temples will ride up. If too long, the glasses will slide down the nose. Also, look behind the ear and contour the temple for angle and touch. The more temple contact, the more secure the fit.
- Clean the glasses again and ask if they feel comfortable, straight, too tight, too loose.
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