Barberini photochromic glass sun lenses have the quality of adjusting to rapid changes in light transmission becoming more or less dark according to the light intensity.

These lenses allow for a much wider use of our sunglasses because they can be worn under overcast skies as well as in broad daylight, in the shade or in artificial lighting; but most of all they are practical in situations that require moving rapidly from one lighting condition to another. So far, photochromic lenses have been available only in brown and gray, which strongly limited the request in fashion and design. Today Barberini can produce them in a wide range of colors by using the highly advanced Corning technology, granted in exclusive called Hydrogen Firing. In this reducing atmosphere, the glass is submitted to a chemical transformation producing in the lens a gradual change in color as well as a change in its transmission curve and optical characteristics. It is by changing the parameters of the reducing process that Barberini obtains various chromic combinations. Barberini with the new H₂FTM Photochromic lenses is able to offer an infinite variety of colors and for the first time you can avoid having to purchase tons of glass to obtain a different color lens, allowing designers to be free in their creativity. With only one kind of blank, different colors can be created and the customers’ request can be limited in quantity especially for commercial samples, etc. It is not a coating applied to the lens, which could be subjected to scratches or abrasions, but a coloring within the glass material itself. All types of other coatings can be applied on H₂F Photochromic lenses.