UV Analysis in Ophthalmology: Spectrophotometer Applications for Eyeglasses and Contact Lenses

Eyewear serves and important role in vision correction, UV protection, and style. Monitoring of lens coatings using UV analysis is imperative for measuring color and reflectance value. Image Source: Flickr user Emma Royle

Did you know that 6 out of every 10 people around the world wear eyeglasses, contact lenses, or have had corrective eye surgery due to visual impairments? Even without the need for corrective lenses, tinted eyewear offers protection from the sun and is often a desired accessory for individual style. UV analysis plays an important role in ophthalmic eyewear because it provides the ability to measure a variety of lenses and coatings. Spectrophotometers are reliable tools for UV analysis because they are designed to quantify color, reflectance value, and UV protection in plastic, glass and contact lens wear.

Measuring UV transmittance in ocular protection

Optical protection is more important than ever due to the recent awareness of potential damage from solar ultraviolet (UV) radiation. Ocular protection can be measured using a spectrophotometer to analyze the light absorption of the lens coatings. The ability to measure and evaluate the absorptive properties of coated lenses allows eyewear developers to produce the highest quality of eyewear, which will assure protection against harmful UV rays. These measurements need to be precise in order to comply with FDA (Food and Drug Administration) guidelines in non-prescriptive sunglasses. Spectrophotometers are designed for easy use and accuracy, which are both essential to this industry.

UV analysis is important for regulating coatings in prescriptive eyewear as well. Many of these coatings are tinted for added desirability and protection. The American National Standards Institute (ANSI) has developed strict guidelines to ensure the light transmittance values in tinted lenses meet regulations in order to properly view light signal changes.  The ANSI requires that transmittance values be measured and quantified using spectral analysis to ensure safety while driving. The U.S. National Library of Medicine National Institutes of Health revealed information that was collected by the ANSI which stated that “approximately 50% of the sampled tinted lenses failed to meet at least 1 of the ANSI requirements.” Failure to meet these regulations not only leads to non-compliance but can hinder driving safety as well.

Prescriptive lenses are often coated with tinted materials, many which fail to meet traffic safety guidelines for light color changes and color shift recognition. Image Source: Flickr user Nicole Kasper

Anti-reflection (AR) coatings are also a popular consumer choice because of their ability to reduce glare and produce clearer vision. AR coatings can vary due to thickness, making accurate measurement essential for quality control. UV analysis and spectral reflectance are needed to evaluate multiple coatings of AR materials in order to create the highest quality of product for the consumer. These measurements depend on specific geometric angle observations in order to accurately quantify data for desired results and repeatability. Spectrophotometers vary in geometric composition according to specific product analysis and can be adapted for a variety of needs.

UV analysis of contact lenses

Contact lenses are also being produced with ultraviolet absorbing monomers that can reduce UV transmittance. UV analysis plays an important role in measuring UV transmittance in contact lenses through the use spectrophotometers. Spectrophotometers measure both absorption and transmittance characteristics of contact lens materials to provide a UV analysis of the product’s protective value. Contact lenses which have been designed to block the transmittance of UV radiation are shown to offer protection that is comparable to plastic or glass protective lenses. This has led to the development of a whole new trend in protective eyewear.

Contact lenses are now being developed that can protect the eye from harmful UV radiation. Image Source: Flickr user n4i

Ophthalmic Measurement Options

Spectrophotometers are available in a variety of options and modes which can provide accurate UV analysis. Choosing a product that is specifically designed for optical lens measurement is important for guaranteeing accurate results and developing quality products. HunterLab specializes in ophthalmic lens color measurement with several options designed specifically for this purpose. Our staff is knowledgeable and can provide helpful advice when choosing a product to meet both your needs and budget expectations. We offer exceptional customer support and are here to answer all your color measurement questions. Contact HunterLab today to learn more about how UV analysis can take your optical products to the next level.