Sunglasses are fashionable accessories to make you look nise and cool, I think is important for us to know how this shades are made. There are many shape and sizes of these sunglasses, hey come in different colours and brands. There aredifferent type of sunglases such as polarized, prescription, clip-on, flexible, men's, women's, unisex, children's, designer,
and custom-made sunglasses. Also available are police, pilot and rescue sunglasses, biker,
skier and other sports sunglasses. We also have sunglasses with built-in audio digital players.
Now the question is how are all these different sunglasses made? There are different type of lenses used in sunglases. The advantage of using glass lenses is that they have better visual quality and are more scratch-resistant than plastic ones. Photo chromic lenses darken reaction to light. Glass photo chromic lenses are more efficient in the reduction of Ultra Violet light rays. For gradient Lenses they are darker on top and gradually become lighter toward the bottom. For polarized lenses the materail used in tinting them are normally brown or gray.
Any color tint can be usedFor high index, Trivex, as well as polycarbonate,any color tint can be used .

The variation in color lenses is proportional to the levels of protection from the UV rays of the sun. For instance, amber and brown lenses give more protection by absorbing the UV light more. In addition adding anti-reflective coatings to clear lenses will protect the eyes from UV radiation. The best level of protection from UV rays is 100 per cent. The anti-reflective coating has an additional benefit of helping to protect the lenses from some surface scratches.

It is important that the lenses properly fit in the selected previously manufactured frame;
which means, the lens needs to be ground to fit the frame's size and shape. Morehover,
the lens must be ground with respects to the prescription in order to solve refractive errors in the customer's vision. Take for instance Myopic vision the eye problem require a prescription forthe sunglasses. Other types of sunglasses prescriptions are for bifocals, progressive bifocals and trifocals in which a larger size lens could be needed to accommodate the lens progression. Edger is the name of the grinder that is used to grind the lenses to the specifications of the prescription. It is important that there is a constant source of water running over the lens while it is being ground in order to reduce the heat caused by friction on the glass.

If this is not done the friction heat can cause the glass to crack or break. Apart from above reasons,Water also makes the grinding easier and smoother on the edge and prevents scratching of the surface from dry glass. On the completion of the grinding the lenses are cleaned,at the same time tint is added. This is done by dipping the lens in a tint solution which is absorbed into the lens. The longer it is dipped, the darker the tint. Lastly the lenses are thoroughly rinsed and dried then are fit into the sunglasses frame and the frame is secured tightly around the lens by tightening the screws on the frame. Sunglasses frames are mass-produced from products like plastic, nylon, carbon fiber and metal.

The process of making sunglasses has come a long way from when Roman Emperor Nero held polished light emerald glass gems up to his eyes and Chinese attached ceramic weights to the ends of ribbons draped over the ears in order to keep on their cool sunglasses.