What are the Advantages of Free Form Progressive Lenses
What are the Advantages of Having Optimized Free Form Progressive Lenses in My Glasses?
Optimized Free Form progressive lenses from Goodrich Optical are becoming far more popular these days. Primarily because of their visual performance. Couple that with their custom position of wear characteristics and you have unmatched optical performance from your eyewear.
What are Optimized Free Form Progressive Lenses?
The Technical Answer: Optimized Free Form Progressive lenses are Individually Measured, Computed and Manufactured Progressive Addition Lenses That Use Computer Programs To Run Three-Axis Generators and Polishers Which Provide the Wearer With an Optimized Lens Correction For Their Visual Defect.
Uhh WHAT!? Let me try to make a rather dry, technical subject a little easier to understand.
Free Form is a manufacturing process that allows the creation of complex surface curves and designs with extreme precision. Made using modern computer technologies that allow you to achieve better vision They are the most popular type of high-definition lenses.
So How Does Position of Wear Optimize a Prescription?
Position of wear is the term used to describe the differences in how the glasses fit on your face, compared to the phoropter in the exam room. At Goodrich Optical, we use your position of wear compensated Rx to provide you with the best representation of the doctor’s prescription in the glasses you wear.
To understand why we do this, compare this brief list of differences between the refraction done in the doctor’s exam room and those found in the fitted glasses as you wear them.
Doctor’s Office-
- Vertex Distance: Average is 13-14mm.
- Pantoscopic Angle: The lenses in the phoropter or trial frame are straight up and down, which equates to a pantoscopic angle of zero degrees.
- Face Form or Wrap Angle: In the phoropter, the lenses are held in a flat plane, creating a face form of zero degrees.
- Pupillary Alignment/PD: The phoropter, measures the IPD as a total of the two eyes (binocular). Meaning, they cannot measure the monocular difference typically found.
- Pupillary Height: The patient’s eye is normally aligned with the geometric (optical) center of the phoropter’s test lenses.
Properly Fit Eyewear
- Vertex Distance: Measured values range anywhere from 8 to 20mm.
- Pantoscopic Angle: Typically, 6 to 8 degrees, but could be anywhere from 0 to 15 degrees.
- Face Form, Wrap Angle: Values from 0 to 10 degrees are average. Wrap-style sunglasses can be as much as 25 degrees.
- Pupillary Alignment PD: If done properly, each eye is measured (monocular values are taken). Differences between each eye of up to 4-5mm have been seen, and 1-2mm is pretty common.
- Pupillary Height: It is not unusual in today’s frame styles for pupal placements of 2-6mm above the geometric (but not always the optical) center of the lenses.
Position of wear compensation applies these values to the doctor’s findings when determining the adjusted values to be used in creating the lenses. An optimization program takes the doctor’s prescription, combines it with the patient’s unique position of wear values and recalculates a prescription that “compensates” for these differences. Referred to as the “Compensated Rx”. The result is a much more precise representation of the doctor’s prescription which creates lens performance not achievable with standard lens design methods.
Benefits of Optimized Free Form Progressive Lenses
- Wider field of vision due to the back-surface design.
- Highest level of visual acuity at all distances.
- Wider intermediate and near zones.
- Greatly reduces “swim” effect
- Lower levels of unwanted astigmatism.
- Aspheric/atoric designs make the lenses thinner and flatter.
- Reduction of Higher Order Aberrations.
Here is a comparison of standard versus Free Form lenses:
Standard Lenses:
A Standard lens begins as a semi-finished, pre-molded lens that already has a particular progressive design molded on the front surface. In the manufacturing lab, the prescription will be generated on the back surface of the lens and the mold is not altered.
Optimized Free Form Lenses:
Optimized Free Form lenses are made using software that calculates the person’s prescription when combined with the patients position of wear measurements. This allows Optimized Free Form lenses to be digitally ground to each individual patients, individual eye.
Free Form Lenses:
Similar lens characteristics to Optimized Free Form but created using a set of average values (Default) for the position of wear compensations. While an improvement over standard lenses, they do not offer the precision optics of their Optimized counterparts and are often used by places that do not have the knowledge or training to collect the accurate position of wear measurements needed to create Optimized Free Form lenses.
Like UHD TV:
To understand the difference, consider the improvements in TV technology. First, there was analog TV. That would be the lenses you wear now. Then came HD TV with its’ higher resolution. Consider that a Free-Form or HD lenses. Today you can buy a UHD TV with a picture like no other. That is what Optimized Free Form lenses represent. Imagine having the same experience with your glasses. Sure, you can probably see fine with the glasses you have, just like watching analog TV was fine when that was all you had.
What Are the Benefits of Optimized Free Form Progressive Lenses?
While there are many, here are a few of the benefits that Optimized Free Form lenses from Goodrich Optical have to offer:
Personalization:
Each lens is custom created using the unique position of wear measurements our opticians collect. Now you can select that trendy fashion frame you saw in our office and using Optimized Free Form technology, we will custom tailor the lenses to your prescription.
Improved Visual Clarity:
Optimized Free Form technology creates lenses with increased visual performance, allowing you to see better than ever before, at any distance.
Accommodate All Prescription Types:
Optimized Free Form lenses are able to be created in a multitude of prescriptions, including extremely strong prescriptions. In fact, stronger prescriptions benefit even more from Free Form designs.
More Attractive Looking:
Optimized Free Form design technology creates lenses that are not only optically better, they are aesthetically better as well. With thinner, lighter lenses with less apparent “swim”.
Who Should Buy Optimized Free Form Progressive Lenses?
There has been a huge increase in the number of people requesting Free Form progressive lenses at Goodrich Optical, and they are a great choice for many. If you have a strong or unusual prescription, want the highest visual clarity, or simply are not happy with the vision through your standard progressive lenses, consider giving Free Form Progressive lenses and try.
Optimizing Single Vision Lenses
Do single vision lenses benefit from position of wear compensation? You bet! Stronger prescriptions, those with moderate or greater cylinder power and unique fitting situations all will greatly benefit from POW optimization. They offer clear, natural, distortion-free vision, all the way to the edge of the lens.
