Speed is one of the main characteristics of Carl Zeiss PhotoFusion lenses. According to the climate and light conditions and lens materials, they are said to darken 20% faster than previous ZEISS photochromic lenses, and importantly, the fade speed is twice as fast. It may take 15 to 30 seconds to dim, and a transmission that fades out to 70% may take five minutes. The transmittance is rated at 92% in the transparent state and 11% in the dark state.
PhotoFusion is available in brown and gray colors, 1.5, 1.6, and 1.67 indices, as well as the manufacturer’s progressive, single vision, digital and DriveSafe lenses, which means that practitioners can provide patients with maximum flexibility in lens selection.
Carl Zeiss Vision Marketing and Communications Director Peter Robertson said: “Due to the rapid response of Zeiss lenses to light and 100% UV protection, Zeiss lenses with PhotoFusion provide practitioners with a single lens solution suitable for all eyewear wearers—— Whether it is indoor or outdoor.’
Traditionally, when UV radiation levels are low and extreme temperatures, the performance of photochromic lenses struggles.
Compare a skiing environment with high levels of UV and low temperatures to a dry, dusty desert with high temperatures and low UV levels. In the past, it was difficult for photochromic lenses to cope with this situation. On the ski slopes, the lenses are too dark-and too slow to fade. In hot conditions, the color density does not reach the required level, and the activation speed is usually very slow. For many practitioners, this unstable performance is the main reason why photochromic lenses are not recommended.
Hoya’s proprietary technology Stabilight is the core of Sensity lenses. Tested in different climates, regions, altitudes and temperatures, Stabilight is said to provide consistent photochromic performance. The lens darkens into a category 3 sun lens shade faster than ever, and becomes clear immediately after the ambient light intensity decreases. During these transitions, full UV protection is still maintained.
The company stated that the new spin coating process utilizes proprietary dye composite materials and is tailored for advanced free-form lens production, which means the highest optical quality, better utilization of the entire lens area and the most consistent performance.
Sensity can be used in combination with all high-quality Hoya coatings and is compatible with single vision, bifocal and progressive lenses, including the Hoyalux iD product line.
The lens is available in single-vision stock CR39 1.50 and Eyas 1.60, with a variety of treatment options.
The latest version of Rodenstock’s ColorMatic series uses photochromic dyes, which have a larger molecular structure and individual molecules are more sensitive to ultraviolet light. The company says this allows patients to experience perfect coloration in shadows. These lenses are said to be darker than before at higher temperatures and can better balance the tinting and fading time when indoors. It is said that the life span of the dye has also increased.
The new colors include fashion gray, fashion brown and fashion green. Rich brown has the effect of enhancing contrast, gray provides natural color reproduction, and green has the effect of relaxing the eyes. The lens also maintains its true color throughout the darkening process. You can also specify three contrast-enhancing tones of orange, green, and gray, as well as a silver mirror coating.
Photochromic lenses are often known for being a bit uncool and targeting mature audiences. Although developments such as green tones and matching with fashion brands have eliminated this situation to some extent, truly fashionable photochromic lenses are rare.
Fortunately, Waterside Labs has a colorful collection from Sunactive on hand. The series is available in six colors: pink, purple, blue, green, gray and brown, which is very suitable for patients who want to get popular colors from sunglasses. Colored lenses will not fade to completely transparent, but maintain their fashionable colors.
The Sunactive series is suitable for the company’s progressive lens and curved single vision product series. Indexes of 1.6 and 1.67 inches have recently been added for gray and brown.
Vision Ease’s photochromic series products were released at the end of last year, aiming to provide patients with dimming and receding performance. Research conducted by the brand shows that this is the primary consideration for patients when choosing photochromic lenses, and eight in ten patients said they compared brands before buying.
It is said that the internal light transmittance test shows that the new photochromic lens is 2.5% clearer indoors than the recognized national brand, and 7.3% darker outdoors. Compared with domestic brands, the activation speed (27%) and retreat speed (44%) of these lenses are also faster.
The new lens can block 91% of outdoor blue light and 43% of indoor blue light. In addition, the lens contains an improved true gray. Polycarbonate gray styles include: semi-finished single light (SFSV), aspherical SFSV, D28 Bifocal, D35 Bifocal, 7×28 Trifocal and eccentric Novel progressive.
Transitions stated that real-world tests reflect the wearer’s experience and are where the best measurements of photochromic lens performance can be obtained. By testing the lenses in more than 200 different real-life conditions, these lenses represent more than 1,000 scenes. Combining temperature, light angles, ultraviolet and weather conditions, and geography, Transitions Signature VII lenses are more responsive.
Research conducted by the company found that 89% of clear lens wearers and 93% of photochromic lens wearers currently describe their Signature VII lens experience as excellent, very good, or good. In addition, 82% of clear lens wearers believe that Signature VII lenses are better than their current clear lenses.
Transitions Signature lenses are available in 1.5, 1.59, Trivex, 1.6, 1.67 and 1.74 specifications, but the scope and materials of each supplier are unique.
Brown, gray, and graphite green are available from: Essilor Ltd, Kodak Lens, BBGR, Sinclair Optical, Horizon Optical, Leicester Optical, United Optical, and Nikon. Brown and gray are available from most lens suppliers in the UK, including: Shamir, Seiko, Younger, Tokai, Jai Kudo, Optik Mizen and a series of independent laboratories.
Although it is not a lens product, the Umbra system newly developed by the British company Shyre provides a new photochromic product option for the ophthalmic laboratory in the form of a dip coating process.
The research and design of the dip coater started in 2013 by directors Lee Gough and Dan Hancu, who are looking for solutions to overcome the limitations of the batch process of adding photochromic dyes as Gough said.
The Umbra system will also allow laboratories and larger eyewear chains to use their own coating solutions for any type of transparent stock lenses. Shyre’s photochromic coating is applied after the formulation is created after surface treatment and before trimming. You can specify custom colors, along with different tonal levels and gradients.
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Post time: Oct-13-2021