Anti-reflective coatings now do much more than the name suggests. HOYA is one lens lab focusing on properties that promote greater durability and scratch resistance, culminating in a new flagship coating, Hi-Vision Meiryo Diamond, offering the clarity modern day spectacle wearers expect from their lenses.
There is a list of key demands patients have when they are prescribed a new pair of premium lenses. Clarity of vision is the top priority, but they also want a lens that withstands the rigours of everyday life, and remains in a similar condition to the day they picked up their spectacles from the practice.
Increasingly, patients also want to avoid the need to clean lenses constantly, put up with scratches or feel conscious about reflections.
According to lens manufacturer HOYA, a premium lens doesn’t only set itself apart by the material or design, but requires a high quality coating that elevates the wearing experience and acts as the ‘finishing touch’.
The most well-known of HOYA’s lens coatings in the Australian market has been its flagship Diamond Finish coating, which has been gradually upgraded over the last decade. But the company will soon discontinue this and replace it with its most advanced coating to date, Hi-Vision Meiryo Diamond.
It’s a big deal for the company to launch a new flagship coating, considering the success of Diamond Finish, but HOYA is confident it has delivered tangible improvements. In fact, Hi-Vision Meiryo Diamond is being marketed with some eye-catching statements that HOYA says it has validated through a new testing regime more rigorous than industry standards.
The new Hi-Vision Meiryo Diamond coating will be available from October 2023 and a key feature of HOYA’s presence at O=MEGA23/WCO4 in Melbourne (8-10 September). According to the company, it offers:
• Superior clarity that lasts longer
• Up to 2.5 times better scratch resistance than other market leading lens coatings.
• Stays easy-to-clean up to five times longer than other market leading lens coatings.
• Exceptional clarity due to 56% lower reflectance than other market leading lens coatings.
“Hi-Vision Meiryo Diamond is HOYA’s best new coating that provides exceptional clarity and long-lasting benefits due to its low reflective properties, extreme scratch resistance and what we have found to have unmatched durability,” says HOYA Lens Australia national training and development manager Mr Ulli Hentschel.
“This coating is ideal for consumers who prioritise high-quality and long-lasting clarity over short-term cost savings. It allows patients to protect their valuable lenses from anything that life throws their way, with surface lens protection which extends the lifetime of the lenses.”
The name ‘Meiryo’ was derived from the Japanese word for ‘clarity’. It is both a reference to HOYA’s Japanese origins and a nod to the technological qualities of the coating. The name ‘Meiryo Diamond’ stands for long-lasting durability and superior clarity, and allows HOYA to continue to benefit from the brand equity it has built with the Diamond Finish coating.
Advantages for independent practices
HOYA’s own research shows that for 96% of patients, clarity of vision is a key reason for choosing their glasses, and 80% of patients are willing to spend more for high quality lenses that provide clarity. This represents a clear opportunity for independent optometry practices.
But Hentschel says patients don’t want to only be able to see clearly when they leave the store – they want high-quality, durable lenses that last.
“Our previous flagship Diamond Finish coating achieved global success and was one of the most premium coatings on the market. It was upgraded over the years, but when developing a new flagship coating in Hi-Vision Meiryo Diamond our R&D team were keen to deliver something that is quite different to what we had before, and led the market in several ways,” he says.
“Some key advantages for the eyecare professional include confidence in recommending the best lens protection available through innovation and technology. We also want patients to be so satisfied with the lens they received, they return to the practice seeking the same lens, but with an updated prescription. In turn, happy patients will refer their friends and family, helping build the practice’s reputation on quality and value.”
There are many key qualities of the Hi-Vision Meiryo Diamond coating. These include: 100% UV protection on the front surface and extra protection on the back, scratch resistant surface lens protection that extends the lifetime of the lenses, anti-reflective properties for clarity of vision and better aesthetics, dirt repellent and easy-to-clean, water repellent for optimal vision in rain or condensation, and enhanced contrast and glare reduction during the day and at night.
When it comes to the lens clarity and lower reflectance, a key feature with Hi-Vision Meiryo Diamond is a new subtle reflex colour.
The dominant wavelength is different from HOYA’s standard green, but is light blue, instead. There is a very low luminous reflection, which the company says is 56% lower than the previous generations and lower than other market leading lens coatings. This will also lead to better aesthetics for the wearer due to less “mirror effect” of the lens surfaces.
How HOYA tested the coating
When it comes to the value proposition of Hi-Vision Meiryo Diamond, HOYA sums it up with the phrase: “Clarity that lasts”, or in other words, lenses that outlast their prescription.
That means a major emphasis on scratch resistance, durability and easy-to-clean properties. The company has achieved this with its advanced multi-layer technology involving what it describes as a “super-resistant” hydrophobic layer that prevents water stains, and an anti-static layer that repels dust and dirt.
But with all of that said, how can eyecare professionals and patients be confident the lens will last as HOYA has intended?
To address this, HOYA set out to develop the LongLife Index evaluation method. This new regime is a measure of the performance and durability of anti-reflective lens coatings and comprises five tests that the company says are more rigorous than industry standards.
“The LongLife Index was developed and adopted by HOYA as a working standard. Passing the rigorous and severe tests gives us the confidence that the coating is of the highest quality and is able to endure extreme conditions and various lifestyles,” Hentschel adds.
Hi-Vision Meiryo Diamond was subjected to the test – in addition to two other HOYA coatings and five coatings from competing lens companies – and compared. The five tests include:
Droplet test – this assess how easy lenses are to clean and their water resistance. For this test, lenses are wiped with paper up to 10,000 times, then water droplets are used to measure how much hydrophobic coating remains. The shape of the droplets on the surface determines the amount of hydrophobic coating left behind, and thus how slippery the lenses are and how easy they are to clean. The more spherical the droplet, the more hydrophobic coating is present; the flatter the droplet, the less hydrophobic coating present.
Sandpit test (HOYA Bayer value) – this is a well-known test for resistance to abrasion. Lenses are placed in a ‘sandpit’ full of gravel and are shaken vigorously 800 times. The lenses are then analysed for transparency and the Hoya Bayer value is calculated.
Steel wool test – to quantify resistance to harsh scratches, HOYA used carbon steel wool brushed on the lens surface. The test uses weights up to 2.5kg to apply pressure onto the steel wool, which moves side-to-side 40 times (20 cycles) across the lens surface. The lenses are then analysed for scratches under artificial lighting.
Oven test – testing for heat resistance, the lenses are subjected to temperatures exceeding 95°C in a laboratory-graded oven. The temperature is gradually increased until the cracking point of
the coating.
Extreme weather test – the lenses are put into a machine called a QUV accelerated weathering tester. This tests the lenses by exposing them to cycles of UV light and moisture at elevated temperatures – similar to the harsh equatorial climate. The remainder of coating is measured every week up to a total of four weeks. This is combined with a cross hatch test to reveal peeling from the lens surface.
Overall, HOYA says Hi-Vision Meiryo Diamond was superior or equal on almost every measure (visual clarity, durability of cleanability, durability, scratch resistance, thermal resistance, resistance to peeling).
“Our testing shows that we can bring our coating to market with confidence that it performs better than major competitors overall, which we hope will underpin long-term practitioner-patient relationships,” Hentschel says.
“Our aim with this coating is for patients to feel excited and feel good about how they look in their glasses, not only when they first put them on, but after days, weeks, months and even years of wearing them, because the true test is time.
“We want to save them time and allow them to live worry-free so they can enjoy life without the need for constant maintenance.”
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