Anti-reflective (AR) coating for eyeglasses is increasingly popular with consumers – for aesthetic reasons, for improved vision (eyeglass lenses with AR are more transparent than uncoated lenses) and most recently for blue light protection from heavy screen use. If it’s so popular, why does it typically take 3-5 days to get coated lenses from an ophthalmic manufacturing lab? One of the main bottlenecks in labs is the coating room due to long lens degas and hard coat cure times combined with the fact that large batches are being coated, which adds time since batching means that lenses have to be accumulated. These processes can take as long as 10 hours. But there’s a better way with an innovative approach to AR coating: Express AR, producing lens coatings in just 1.5-2 hours. Furthermore, Express AR almost completely automates the coating process, which traditionally is very manual labor intensive.
The new process begins with blanks that have factory hard and AR coatings as well as a special grip layer already applied on the front side. This happens in large mass manufacturing facilities. Coating only one side, the back side, in the local lab greatly reduces process time and increases the throughput of any box coater. Express AR uses three special components:
• An alloy-free lens blocking technology can be used inside a box coater without affecting the pump down time or the AR stack. This also protects the pre-applied front side coating during the lens surfacing and degassing processes.
• A non-tintable solvent based spin hard coating that works as well as most dip scratch coatings and UV-cures in seconds, where dip coating takes hours.
• A patented grip over-coating, which is necessary since the pre-AR coated front side, has a slick, super hydrophobic top layer that allows consumers to easily clean their lenses. The grip over-coating keeps super hydro coated lenses on the block.
"Express AR almost completely automates the coating process, which traditionally is very manual labor intensive"
Accelerated hard coating and degassing processes with fast equipment: the automated spin hard coater produces up to 100 lenses per hour per machine. An automated tunnel oven degasses blocked lenses in less than 30 minutes – half the time of traditional degassing. The sectoring and de-sectoring processes use robots instead of the traditional manual labor. The use of robots becomes feasible since the lenses are coated on the block allowing the robots to handle blocks that are consistent in size and shape, rather than lenses. A snap-chuck system secures the lenses in the sector. Not only is this system fast, but it also eliminates issues that manual handling can cause (scratches, mix-ups, etc.). The only remaining manual step is to load sectors into the box coater for AR and afterwards transfer them to the desectoring robots. Frequent automated lens and block cleaning – three times in the process – ensures high yields.
Express AR is easily controlled with an MES (Manufacturing Execution Software) system. It provides real-time data for all machines and production processes, optimizing productivity, and increasing competitiveness. Labs utilizing an MES system collect, track, and show all machine process data for real-time monitoring and intervention via supported devices (tablet, bar code/RFID reader, smart phone/watch, and computer). The MES has a coating batch module that tracks each lens and each breakage per batch and per machine while the Express AR app optimizes loading for automated sectoring and de-sectoring.Express AR is fast and automated AR. It dramatically reduces labor costs, cuts AR process time from up to 10 to less than 2 hours, and eliminates human lens touches.
“This is revolutionary in the world of ophthalmic lens coating methodology;it reduces manufacturing time and increases productivity, which gets the patient their new eyeglasses even faster. This will become the new way to manufacture AR coated lenses.”. “Embrace technology for efficiency, customer satisfaction, and increased profits.”