Crystal Vision (CR) are top quality lenses made by one of the world’s largest lens company.
CR-39, or allyl diglycol carbonate (ADC), is a plastic polymer commonly used in the manufacture of eyeglass lenses.
The abbreviation stands for “Columbia Resin #39”, which was the 39th formula of a thermosetting plastic developed by the Columbia Resins project in 1940.
Owned by PPG, this material is revolutionising lens making.
Half as heavy as glass, far less likely to shatter, and optical quality nearly as good as glass.
CR-39 is heated and poured into optical quality glass moulds – adapting the qualities of glass very closely.
One major change is blue light. Blue light is not new – it is part of the visible spectra.
The sun has been the single biggest source of blue light since the beginning of time with an exposure outdoors 500 times greater than indoors. The change in blue light comes with our knowledge of its effect on the visual system. Thanks to the research done by the Paris Vision Institute and Essilor, we now know that most swine retinal cell death occurs when these cells are exposed to the blue-violet light bands between 415nm-455nm, with a peak at 435nm
Not all blue light is bad for you. However, Harmful Blue Light is.
It is emitted from devices your patients use every day—like computers, smartphones, and tablets.
And since 60% of people spend more than six hours per day on digital devices, your patients will likely be asking what they can do to protect their eyes from this prolonged exposure to Harmful Blue Light.
• Blue-violet light from 415-455 nm has been evidenced as a strong oxidative stress inducer and a defense inhibitor, thus one of the most harmful forms of light for the retina.
• The potential risk linked to the increasing blue light exposure can be modified thanks to the latest ophthalmic lens technology.
• Patient education is critical to raise awareness about both the harmful effects of blue light and existing preventive solutions.
• Blue light is composed of a harmful (blue-violet) and beneficial (blue-turquoise) radiations. It is essential that an ophthalmic lens blocks the former and lets through the latter.
• When comparing different optical solutions for blue light filtering it is important to keep in mind that not only the amount of blue-violet light blocked is important but also the wavelength bands blocked.