Page 70 - Demo

68Ultra-precision machiningUltra-precision machining is a cutting-edge advanced manufacturing technology that produces intricate components with highly accurate dimensions and geometries, usually at the sub-micrometre level, which is 1/100 of the diameter of a human hair. This engineering forms the backbone of innovative technologies in aerospace, electronics, automobiles, optics, and biomedical engineering. Prof. Cheung%u2019s team aims to achieve smooth and precise surfaces with nanometre-scale surface roughness. Given that a strand of DNA is about two nanometres wide, this means the difference between the %u2018peaks%u2019 and %u2018valleys%u2019 of a surface profile cannot be bigger than a single DNA strand. Using state-of-the-art methods such as diamond turning, micromilling, micro-grinding, single-point diamond machining, computer controlled ultra-precision polishing, and free-form machining, the team can make precision injection moulds with the tightest tolerances and optical surface quality, achieving roughness values in the micrometre and nanometre range. These moulds are used to produce lenses with micro/nano-structures and shapes that bend light rays exactly as intended. Examples include the NMDIS lens and autostereoscopic displays for electronic devices. The team continues to push the limits of what is technically possible, achieving ever higher levels of precision.SMALL IS POWERFULDIGGING DEEPER