How Optometrists Build Lenses
When you order a lens, almost every aspect of its production is automated based on readings given by the optometrist. The data an optometrist gains is all digital, which is translated by machinery that shapes and cuts a lens based on your particular specifications. The intricacies of this process are not a secret, but they are a bit of modern manufacturing magic.
First, the eye doctor gives readouts of how you scored in vision tests. These tests are designed to assess different areas of the eye, and give the doctor some quantifiable concept of how you see. Those data points inform a machine how to cut a lens in order to shape it for your eye sight. Depending on the type of symptoms a patient exhibits, a particular geometrical shape must be taken in order to correct the vision. Astigmatism, for example, is corrected with a toric lens. This kind of lens is mostly spherical, with a cap on the end that is closer to an oval shape.
Once the correct shaping has occurred, an optical coating device is used to give the lens its desired properties. If the client orders anti-glare, or anti-scratch coating, this device allows the optometrist to apply the coating as a thin film that won’t obstruct the patient’s vision.
Ebeam can be used as well, especially if a tint is involved. These techniques help apply a smoother finish, as opposed to sputtering that would create small dimples and imperfections.
After the glasses are coated, the rims are shaped to the specifications of the patient’s face and the final step is trying everything on for the first time.
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