When I was young and dinosaurs still roamed the Earth, I began my experience as a trainer with LensCrafters. In their introduction video for new hires, there was a quote that has always stuck with me: “Don’t ask ‘Why.’ Ask instead, ‘Why not?” That kind of thinking was how LensCrafters rewrote the entire playbook on how we thought about buying glasses. Their “glasses in about an hour” concept revolutionized the entire industry. I’m very much a “why not” kind of guy. (Go ahead ask my friends and family.) That is why I ended up working for Laramy-K. We are a “why not” kind of company. Since our beginning, we have been pioneers and technology-adventurers in both lens production and design. We pride ourselves on embracing change and being way ahead of the curve. Part of having a “why not” philosophy is a willingness to listen. Let’s all put on our “why not” hats for a few minutes and listen.

Optical lenses are now being produced through 3D printing. And to all you naysayers out there, I would love to take this opportunity to say, “I told you so.” Currently, 3D lens printing is very much a case of what might be, not necessarily what is. However, as you are about to find out, things could get rather interesting rather quickly.

To get a better understanding of the technology, I spoke with Guido Groet, Chief Commercial Officer and President of Luxexcel Inc. Luxexcel is based in Brussels, Belgium, and is the current leader in 3D lens printing technology. Guido’s background is in bringing disruptive technologies to market. He started in semiconductor technology in Silicon Valley, helping to bring about the amazing revolution we have seen in electronics. In a prior life, he was actually in charge of $1B of high-end optics business in nano-scale lithography and has since been involved in several startup companies.  

John: I have done hundreds of articles in my time but this one has me a little overwhelmed with questions that come to mind. I’ll do my best to narrow them down. Maybe it would help if you gave me your own “elevator speech?”  

 

Guido: Luxexcel has developed over a period of many years a unique technology to 3D print lenses. Since most people did not believe this could be done, we find ourselves pretty much on our own in this space. Our technology works by building lenses from tiny droplets. The benefit of the technology and 3D print technology in general is to be able to create unique designs, when needed, with little waste. There are obvious operational advantages but even more exciting are the new products that become possible.  

 

John: Is this process still based on a liquid monomer?  

Guido:  Yes. We start with a bottle of liquid monomer then we create very small droplets and position those exactly where we want and then cure them with UV light. The trick is creating small droplets but use many of them to build the lens.  

John: Then how is this different than injection molding techniques? In simple terms aren’t you are still forming a lens with the soft monomer and hardening it when it is the correct shape?  

Guido: We harden the monomer droplet by droplet, making sure that each droplet merges with the previous droplet before fully curing. This enables us to create lenses that are of course fully transparent. An important difference with molding is the flexibility in shapes that are being printed.  

John: My image of 3D printing is a very slow, yet extremely precise, methodical placement and building up (or layering) of material to form the finished product. At what level is the lens building application working? Nanometer? Larger? Smaller? Or maybe to ask it another way, what amount of material is being dispensed at each individual data point?  

Guido: Typical 3D printing is indeed very slow. We use very small droplets (a few picoliters) to achieve the required accuracy. [note: A picoliter is one trillionth of a liter. Still well above the molecular level however.] To achieve our speed of about 4 lenses in an hour we deposit our droplets not one at a time but thousands at each pass. One lens can contain up to a billion droplets. We cure in several steps to make sure we find the exact balance between shape accuracy, transparency and speed. Printing itself takes between 30 minutes and an hour and the machines we currently have installed, print 4 lenses at a time.  

John: Does the lens still need to be edged? Assuming you could feed the printer the frame measurements in 3D, does the printer render a lens ready for insertion into the frame?  

Guido: After the lenses are finished, they need to be coated and edged. Many people ask us why not eliminate those steps? That is something that maybe can be done, however that is not something we are currently focused on.    

John: Then what about cribbing or final lens shape?  

Guido: We do not print exactly to shape but we get close. Waste after edging is just a few grams. Allow me a little sidestep from your question to explain what we see as the big opportunity of the technology. Lets be very clear, most of these smart products require development, and they are not available for sale today, but for several we have prototypes available. The ophthalmic industry has spend 200 years getting to where it is today and what has been achieved is remarkable, great lenses, at attractive prices. The one downside of the current freeform technology is that all lenses are very similar because of availability of blanks and certain process limitations. If you want a product that is different, the current technology might not be the answer. This is where 3D printing comes in. With our 3D print technology we are not trying to recreate existing volume products because then the only difference between us and the existing freeform technology, would be price. With this technology we can do so much more, we can make lenses that are not possible today. What we want to do is to bring two things to eyewear: Full customization, create the exact product that you, as a user need or want. Some examples of custom products: 

  • Extreme prescriptions, difficult to make in volume production
  • Glasses with multiple additions for specific activities and for a specific person (shooters, golfers, pilots …)
  • Prescription inserts for Virtual Reality/Augmented Reality goggles
  • Prisms integrated with the additions
  • Mix difference index materials
  • True one piece prescription visors

When you look at your phone, it is very different from the phone your grandma used 20 years ago. But, when you look at your glasses, they are very similar to your grandma’s. The difference is “smart”. With our technology we can integrate all kind of electronics, screens, sensors, filters, etc. inside your lens making your glasses “smart” Some examples of these smart concepts:

  • Glasses with prescription lenses that change color instantly, when you tap them (electrochromics)
  • Glasses that change prescription depending on eye movement and position. 
  • Driver glasses that check if the driver is not falling asleep, by having an integrated camera in the lens.
  • Bike riding glasses that indicate the user with a light in the lens that there is a truck behind them.
  • A clock or even navigation integrated in your glasses.

Coming back to your original question, we are not trying to be a low cost solution, therefore we are not trying to eliminate as many process steps as possible. We are trying to bring a revolution to eyewear by enabling cool new products.  

 

John: I think the answer is obvious but I’ll go ahead and ask it anyway. I’m going to put you on the spot here. Anyone who has been around for a few years will remember that other companies have attempted similar things. Without naming names I can recall adjustable lens designs, electronic adds, smart-wear technology and supposedly even a multi-index lens. Why should we not be skeptical of another “what could be” scenario?  

Guido: Well since many people have tried these things, there must be a great benefit! Of course we believe that our solution is the one that will be successful, and I believe we are on track with printers working today in commercial labs, and cool working prototypes for smart lenses here on my desk for the applications I mentioned earlier. The great thing about our technology is that it is not a one trick pony, we are not talking about a single product we are talking about a new tool set that can make an incredible range of new products. The limit here is not the technology but our imagination. 10 years from now people will look back and wonder what all the fuss was about. Having said all that we of course have to prove everything works as promised and I am sure there will be some glitches along the way.  

John: I’d like to jump back a question and make sure our readers stop for a moment and think. Let me grab just a few concepts and expand a little. A lens where I can position the add and corridor wherever I want? A one-piece Rx visor or goggle shield? Perhaps a lens that could bring peripheral vision back towards central vision for AMD sufferers?

Guido: A lens where I can position the add and corridor wherever I want? We do have freedom of shape both for the front and the backside. We are starting off with the difficult lenses that are not easy to make in freeform for example bi, tri and quadrifocal lenses with custom prisms and custom cylinders. We can have the optician or the lab position the addition where required and even the multiple additions. We do need to  make sure that the lens remains optically sound therefore we will not release every variation right away and we need to make sure the optical calculation system can check for potential issues. Progressives are not our first priority but we will make sure to include them in future.   A one-piece Rx visor or goggle shield? Yes we can make them. We will start off with the flat ones, like in diving goggles and at a later stage move to curved ones. Again one challenge at a time. It is too easy to stumble if we try to do too much at once.   Perhaps a lens that could bring peripheral vision back towards central for AMD sufferers? That is certainly one of the applications where we can offer a great solution by including localized prisms for example.  

John: Please tell me about coatings. AR, scratch, mirror, blue-light…  

Guido:  We are compatible with many regular industry processes like spin coating, and AR coatings. Our lenses do have a natural blue light filter.  

 

John: I see an index of refraction of 1.53. If you are permitted to answer, does this mean that the CR-39 monomer is the base?  

Guido: The material we use is a custom material we created ourselves, focused on our process needs, which is different from what the blank makers use since they have different requirements. Our material is light weight and has an Abbe number of 45. It is of course compliant with drop-ball impact testing, even the big ball.  

John: What about other indices? 1.586, 1.60, 1.67, 1.70, 1.74. What about the fabled multi-index lens we have been hearing about for 30 years?  

Guido: We have additional materials on our roadmap. Important to remember is that since we have flexibility in lens shapes we can actually create thin lenses without having to resort immediately to higher index materials.   We can also mix different materials thereby creating these fabled multi-index lenses (also known as grin lenses). This will take a while to get into production. Not only the printing itself needs to be worked out but also the whole lens design process. And don’t forget the user aspects, how do users perceive these new lenses  

 

John: What degree of accuracy is being implemented? We say that our free-form generators are working to the nearest 1/100th of a diopter.  

Guido: We are certainly not yet at that level, but we can get there. Remember our focus is not doing what your generators can, but make the products they cannot make.  

John: What about center thickness (CT) and edge thickness (ET)?  

Guido: We have flexibility in lens design. Allow me again a little sidestep. We can print a front surface, a back surface several additions, prisms, cylinders etc. just tell us what you want and we make it. The problem is that many opticians take their products from a catalogue which by definition is not custom. We therefore have developed a software package, the VisionMaster, that allows the lab to create custom lenses and if the lab so wishes they can provide these tools to their customers. The VisionMaster allows you to create the exact lens that the user requires. It allows you to pick a template from our library and on screen add whatever features are required and “tune” the lens. This includes bi-aspherical design optimization, lens thinning, side and center thickness etc. it also allows to position the optical center exactly where required.  

John: What is the power range currently available?  

Guido: Currently +/- 32.00 D sphere, 10.00 D in cylinder, prism 15 D , but of course we will extend this in future.  

 

John: What about specialty products (aspheric, lenticular, blended lenticular, slab-off)?  

Guido: Yes all of them.  

John: Guido, thank you so much for your time. Is there anything you would like to add?  

Guido: 3D printing has changed many industries. Typically the impact is biggest where the product touches people because that requires customization which is exactly what ophthalmics is all about and explains why we have chosen ophthalmics as our focus. Our objective is to work with the ophthalmic industry and enable labs to create amazing new products. On the one hand, we allow the lab to create the exact lens that the customer needs, full customization. On the other hand, we will bring smart to eyewear, in RX. We have proven we can make good lenses and we have prototypes for these cool things: we believe we are at the start of a great revolution. In 2018 we will be present at several shows, so make sure to stop by at MIDO Milan or Vision Expo East. Let me use a quote from one of our customers: “In all industries today, the trend is toward additive manufacturing. We want to be ahead of the curve. You don’t want to be the guy in the darkroom when everyone else has moved to digital photography.” DANNY KELLY – CHIEF OPERATING OFFICER IFB SOLUTIONS    

John Seegers
Director of Education
Laramy-K Optical