The first optical lenses were produced in Egypt in approximately 700BC. Originally glass was used and is indeed still available but now 99% of lenses dispensed in the UK are plastic.
Traditionally lenses have been made by manually grinding a surface to create the correct curves then smoothed, polished and cut to shape and fitted to a frame. It was a manual, highly skilled, time- consuming job.
Relatively recently, within the last 30 years, the introduction of computer-controlled machinery has meant the lens surfacing process has become more automated and streamlined and has opened doors to a new level of optical manufacturing. Initially, a major advancement was the introduction of computer numerical control (CNC), using a computer to control the movements of the grinding and polishing tools, allowing greater precision and consistency in production.
Secondly, and most recently, is the integration of digital technology into the design of lenses. Using computer-aided design and manufacturing (CAD/CAM) the laboratory machines can now follow precise design specifications and prescriptions resulting in lenses that meet more exactly the requirements of each individual. Given specific additional measurements for how a particular frame sits on a particular face, lenses can be customised and manipulated to provide sharper and clearer vision for all or particular tasks.
So, with all these possibilities how do we choose the ‘best’ design for somebody? Well, the best design differs for each individual dependent on your prescription, frame choice, visual habits and lifestyle. When you have a consultation with a Dispensing Optician, they will discuss more than just the frame you would like. Generally, they ask a lot of questions and try to find out what you really want or need from your spectacles. Dispensing Opticians are trained to choose from the huge range of lenses, to determine what would work best for you. They are not being nosey, they are trying to help and trying to ensure you get the best vision you can have and the best lenses for your needs!
