Obviously we are all familiar with hallmarks – those tiny symbols engraved on jewellery and items of precious metal that tell us the date, maker, location and purity of the material used. Did you ever notice that your spectacle lenses are hallmarked? Well if you’ve ever seen some strange little symbols etched on your lenses, then that’s what they are! Or on varifocal lenses there are markings which tell us what type of lens you have and where they are placed.
The engravings on lenses are so shallow and so tiny that the human eye cannot detect them when the specs are in place and you are looking through them. To people looking at you, the markings are rarely visible, unless the light happens to hit them in exactly the right place and the observer is looking straight at them. If you do want to take a look at your lenses and see if they have markings, then stand under bight over head light and breathe heavily onto the lens. As the mist appears you might see some minute little marks engraved. If it is a manufacturers hallmark then it will be in a random place on the lens, depending on the axis or angle of your prescription. This is applied in high quality lenses where you have paid for a branded lens.
If you have varifocals, then all lenses will have markings when you first get them. In time, and as you diligently polish your specs the marks will lessen, and even the most eagle eyed will no longer be able to see them! The varifocals will have the manufacturers mark, the power of the reading segment, and the lens type marked on them. Makes you wonder how on earth you could see through them! They also have tiny little circles or elliptical shapes etched at the temple and the nose edge which allows the optician to tell where your clear areas of vision are. If you specs get seriously bent out of shape and you then need to have them re-aligned, the optician will use the tiny engravings as a reference point, to ink a full varifocal template onto the lens. The specs can then be re-fitted and the ink removed. A vital tool in ensuring the continued success of your varifocal wear.
So in an idle moment you can take a look at your lenses and if your sight is sharp enough, you’ll see the reassuring sight of hallmarks and markings that tell us about your specs.