As product customisation and personalisation become a trend, 3D printing technology enables eyewear manufacturers significantly reduce production time and bring diversified eyewear products to consumers, he said. Giving Lithuanian start-up Dear Deer Eyewear as an example, Mr Chan said the company uses 3D printing technology to field orders. A New York start-up King Children uses 3D projection software to map customers’ faces and make unique glasses for their unique characteristics.