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Resources

July 2021 Resources

IOT Free-Form Insights Part 15

There are many steps in an ophthalmic lens journey, and each can impact lens optical quality and performance. It starts with precise refraction by the doctor utilizing calibrated equipment: next step, precision measurements taken by the optician/technician using calibrated instruments. With the first two steps fulfilled, the lab’s free-form surfacing generators apply the free-form design to the uncut lens blank.
June 2021 Resources

IOT Free-Form Insights Part 14

There are many steps in an ophthalmic lens journey, and each can impact lens optical quality and performance. It starts with precise refraction by the doctor utilizing calibrated equipment: next step, precision measurements taken by the optician/technician using calibrated instruments. With the first two steps fulfilled, the lab’s free-form surfacing generators apply the free-form design to the uncut lens blank.
June 2021 Resources

IOT Free-Form Insights Part 13

Why compensate lenses? Free-form lens design and surfacing technology compensate the lens surface, making the effective power perceived by the patient in the primary gaze position match the prescribed power given by the refracting doctor. Why are they not the same? Short answer: The trial lenses used to refract the patient are flat and sit perpendicular to the patient’s visual axis in the primary gaze position, but when the lens is worn, it forms an oblique angle to the visual axis, inducing oblique aberration, changing the effective power perceived.
April 2021 Resources

IOT Free-Form Insights Part 12

In Part 11, we learned about IOT’s foundational technology, Digital Ray-Path®. This technology minimizes oblique aberrations in customized free-form lenses. We learned that “The value of the merit function is given by a weighted sum of the optical aberrations of the lens system. To achieve the best lens performance optimization of the optical system means finding the values of the free parameters that make the value of the merit function minimal.” (Dr. Jose Alonso et al)