These lenses have been filmed with a metallic coating to obtain a vertical density gradation.
A metallic coating applied to the lenses of these fine Ray-Ban sunglasses creates the popular mirror look and adds extra protection for strong glare conditions.
Ray-Ban B-15 high contrast brown lenses screen out blue light to improve contrast and sharpen details, providing 85% visible light absorption and 100% UV protection.
Ray-Ban G-15 neutral gray lenses transmit all colors equally so they retain their true values, providing 85% visible light absorption and 100% UV protection.
Ray-Ban RB-3 green lenses feature absorption balanced with the eye's sensitivity to colors for peak acuity, with 71% visible light absorption and 100% UV protection.
Bausch & Lomb Ambermatic lenses for their Ray-Ban sunglasses were the first true photochromatic sunglass lens which when combined with Ray-Ban gold plated and 10k and 12k gold filed shooter and outdoorsman frames became a classic of vintage sunglasses design and optical quality innovation. The B&L Ray-Ban Ambermatic lens has photochromatic properties that change density depending on the degree of both brightness and temperature. Taking its name from the color of the lens, Ray-Ban Ambermatic sunglasses change from amber yellow to gray and darker and denser in bright light conditions and in colder temperatures. This is exactly what you would want and expect in bright sunlight or at a ski resort when glare off the snow can become a real problem. The Ray-Ban brand was purchased from B&L by the Italian conglomerate Luxottica in 1999 after which no more B&L Ray-Ban Ambermatic sunglasses or shooters were produced. The small etched BL in the ambermatic lenses near the hinge points was not used in Ray-Ban sunglass lens production until the late 1970's, and the cursive white Ray-Ban trademark logo on the lens was introduced in late 1982 and subsequently present on all Ray-Ban sunglasses including Ambermatics from 1983 onward up until the acquisition by Luxottica. These earlier B&L Ambermatic lenses were of much higher quality, changed color faster, and had a wider range of density than anything produced before or since.
Ray-Ban Ambermatic lenses were often paired with the classic aviator sunglasses frame as well as Outdoorsman or Shooter frames, similar to aviators but with cable (wire) ear stems and an additional bar over the bridge referred to as the sweat bar that provided more comfort and made the frame stronger. While pilots initially wore Ray-Ban aviator sunglasses with the green G-15 lens in the 1940's, 1950's, and 1960's, more and more pilots, aviators, sailors, and hunters discovered Ambermatic sunglasses. They could offer a greater contrast between clouds and sky and made it easier to see objects while at the same time progressively blocking the light and providing 100% UV protection. Ray-Ban Ambermatic sunglasses have been called "smart sunglasses" given how they adjust to the prevailing light conditions at the time. On overcast and rainy days, Ray-Ban Ambermatic sunglasses have a light amber tint to cut through haze and sharpen vision. On warm and sunny days, they turn progressively more brown to block the glare. On cold and sunny days, the Ray-Ban Ambermatic aviator sunglasses and shooters change to dark gray for better protection from direct and reflected glare. On cloudy days, Ambermatic sunglasses change to a lighter brown. Following on the success of Ambermatic sunglasses, B&L Ray-Ban subsequently introduced the Changeables line of photochromatic sunglasses and shooters which offered very similar properties but in which the density color change was even more dramatic than in the Ambermatics.
B&L Ray-Ban Changeables sunglasses incorporate unique B&L photochromatic lenses that react to the sun's brightness to protect your eyes in all light conditions. Regular Ray-Ban Changeables sunglasses darken to compensate for varying outdoor light conditions. Ray-Ban Super Changeables darken even more for stronger light conditions and more sensitive eyes, and both Changeables and Super Changeables filter out 100% of harmful UV rays that can harm your eyes. This change in lens density which results in the lightening and darkening is a lifetime feature of these B&L Ray-Ban lenses and will not disappear or weaken over time.
Ray-Ban Changeables sunglasses darken to 75% of their full capacity within the first minute of exposure to sunlight. Out of sunlight, they lighten half way within the first 10 minutes and about 75% within the first 90 minutes. When new, Ray-Ban Changeables sunglasses and lenses require a breaking in period of several complete darkening / lightening cycles to bring them up to their normal performance. Changeables lenses were also heat treated to make them very impact resistant, but they are not shatterproof or breakproof nor do they have the extreme scratch protection characteristic of Ray-Ban Diamond Hard lenses. B&L Ray-Ban Changeable photochromatic lenses were made to the same standards of optical excellence for which B&L was always known. Following the sale of the Ray-Ban brand to Luxottica in 1999, Bausch & Lomb ceased making Changeables lenses for Ray-Ban sunglasses and they ceased to be offered in the original form.