Page 67 - Demo

65Smoothness, at a nanometric levelThe partnership developed the Novel Nano Multi-ring Defocus Incorporated Spectacle (NMDIS) lens, known commercially as MyoDisc. This lens combines advanced optic design and ultraprecision machining with a unique tangential continuity nano multi-ring structure. %u201cWe smoothed out the transitions between the nanometric rings to achieve seamless connections. As a result, the NMDIS lenses look just like those in regular glasses%u201d, explains Prof. Cheung. %u201cNo existing equipment could measure the power of a spectacle lens across its whole span, so we developed a proprietary defocus measurement method to make sure every point on the lens is optimised optically. This ensures that wearers can adjust to the NMDIS lenses with ease and comfort.%u201d To reduce manufacturing costs, the spectacle lenses are produced by injection moulding instead of machining them individually. However, the ultra-precision moulds for nano rings are still expensive to produce. To cut costs, the team moulds only one side of the lens with nano rings for defocus, while the other side uses a regular mould for correcting astigmatism or myopia, which is much cheaper. This means all prescriptions up to -10.00 only require one ultra-precision mould. VST launched the NMDIS lens in December 2022. As at October 2024, 30,000 pairs have been sold in Mainland China and Hong Kong, helping some 30,000 children combat myopia progression while retaining clear vision. SMALL IS POWERFUL