How your glasses are made

The process of making spectacles is quite an interesting one, so we thought we'd show you how it's done in our on-site lab.....

First of all, your lenses will either be looked out from stock, or supplied as a bespoke order from a well-known manufacturer such as Rodenstock, Zeiss or Essilor.

We start by scanning your frame in a 3D tracer. This measures both the shape and curvature of the lens shape to a high degree of accuracy.

This information is then sent to another machine. Using the fitting measurements taken at the dispense, your lenses are then centred on an LCD display and blocked up ready for cutting.

The lenses are then cut down to size using modern CNC technology.

Once they've been cut, they need to be finished by hand in order to remove the rough edges.

If you require a tint, the lenses are then immersed in a specialised tinting unit. Once the minimum operating temperature is reached, a light tint will only take a few minutes. Very dark tints, however, can take quite a bit longer.

For fully-rimmed spectacles, the lenses are now ready to be fitted to the frame. Prior to insertion, however, the frame will usually require some adjustment. Its curvature needs to match the lens curvature to ensure that the lenses stay secure and don't protrude too much from the rim.

For rimless or semi-rimless, more steps need to be followed:

For semi-rimless, we need to cut a groove along the lens. This is to support the nylon cord which will attach it to the frame. We do this manually on a separate machine so we have more control over the position and depth of the groove.

For rimless, we need to drill the lenses and assemble them to the mount. Again, this is a highly skilled process which is done manually. We carefully measure the position of the drill-holes on the dummy lenses, then replicate these on your prescription lenses. After drilling, the size of the holes usually needs to be increased a little to ensure a perfect fit.

With most modern designs a plastic plug then needs to be fitted into which the pins of the frame are inserted. Some frames, however, still use nuts and washers for assembly. Special care is needed in both cases to avoid the risk of chipping or breakage.

Once your spectacles have been assembled, they are then "set up" to ensure that they are completely straight and likely to fit you without requiring too much adjustment at the collection stage.

Finally, they will undergo stringent quality checks to ensure they have been made up exactly as ordered, and that they conform to all the relevant European standards.