Selecting your new frame may be hard work, but it doesn’t have to be that way. At GJO, our qualified optical dispensers will help you choose not only a frame that is fashionable and looks good on, but that fits your face properly and comfortably. They will look at your face shape, shape of the nose, ears, and other features to see whether the frame is the correct size and also a comfortable fit. There is no sense having an Instagram worthy frame, if it is pinching your ears or constantly sliding down your nose as you take a “selfie”.
Some frame considerations your optical dispenser will discuss with you include:
Frame materials – look around most optical floor stock and you will see an assortment of materials such as plastic (usually acetate) , metal of various types such a stainless steel, aluminium and titanium. Some people have metal allergies, which will influence material selection.
Fitting over the nose – the main types are either plastic nose pads, which may come in a variety of styles, sizes and materials, or moulded nose pads in plastic frames.
Types of hinges- spring or flex hinges can be particularly important when frames are likely to be removed regularly, such as with reading glasses.
Thickness of the temples (arms of the frames) – personal preference often dictates this choice, as well as current frame fashions. From a practical point of view when it comes to driving though, some patients opt for thinner temples to minimise obscuring the peripheral vision.
Eye size – the size of the opening in the frame into which optical lenses are placed. Certain prescriptions, such as high plus and minus prescriptions, will cosmetically look better and weigh less in smaller dimension frames.
Bridge size – the distance between the lenses, which also is the size of the "bridge" of the frame, that sits on your nose. Optical dispensers pay particular attention to this, to ensure the frame will remain correctly on your face all through the day.
Once the frame has been selected and adjusted for your face, your GJO dispenser will take a number of measurements that relate specifically to the frame chosen, and how it is positioned on your face. Traditionally, this was done with a black marker pen and a ruler. These days, at GJO, we use state of the art digital measuring equipment to take super accurate measurements! The integrated software allows us to better communicate to our patients the importance of these optical measurements and the frame fitting process. The image below shows an example of the Zeiss tool used to take these detailed measurements, that is attached over the top of the chosen frames.
The important measurements we take for dispensing your new frame, to give the best visual outcome, include but are not limited to:
Pupillary distance – this is the distance between the pupils of the eyes. We measure monocular pupillary distances for each eye individually, taking into account that our eyes may not be 100% symmetrically positioned. This enables the optical centre of the lenses to line up with the visual axis of our eyes, to provide the clearest possible vision.
Fitting heights – the position of each pupil in the frame. This measurement is critical to ensuring where the various zones of lenses such as distance or near vision, occur, and relative sizes of these zones in multifocal or extended focus lens designs.
Pantoscopic tilt – this is the lens tilt about the horizontal axis, with respect to primary gaze of the person. In layman terms, it can be considered as the rotation of the lens bottom towards the cheeks. This measurement influences the ease at which the reading zone is reached by the person.
Back vertex distance – the distance between the back surface of the spectacle lens, and the front surface of the cornea (front surface of the eye). This measurement can ultimately change the power of the lens in front of your eye, according to how it is specified.
Physiological aspects of the patient, such as posture, neck or spinal problems
So, next time you are considering new spectacles, we would love to provide you with a high quality product that you will love, and your eyes will love too!
Felicity Sklavos is a clinical optometrist, specialty contact lens fitter and ophthalmic medicines prescriber who enjoys the great outdoors, in the camper or on the water, in her spare time.