Recently I got back into photography, after a 3 year hiatus. I’ve really enjoyed the experience, and have been pleasantly surprised with the advances in technology made even in that short period of time. We are at the point where top-tier manufacturers are being forced to re-engineer their optics lines to keep up with the advances in sensor technology for digital photography.

One of the things I've always enjoyed about my hobby is its inseparable relationship with physics. For many years, physics has been an unforgiving master of photography, and improvements of our relationship with the fundamental laws incremental at best. However in 2001 Canon released a lens with a promising new technology, Diffractive Optics (DO). The 400mm F/4 lens was 26% shorter and 36% lighter than an equivalent performance lens with conventional optics. It’s reception was less than stellar, partially because of a callousness from the industry toward technologies viewed as trying to “cheat” physics. All stigma aside, the lens performed noticeably worse than other Canon super telephotos in both sharpness and contrast. Anecdotally, I can imagine that consistency in manufacturing was probably a problem as well, given its position as a first article of a first generation technology. It was followed a few years later by a lower-end 70–300mm zoom, again lighter and smaller than a conventionally manufactured lens, but still considered below par in quality. For the next ten years, Canon seemed to have forgotten about the promise of diffractive optics, while still selling these two models to a fan base that loved the more compact design, they didn’t incorporate the technology in any of their new lens designs.

Fast forward to 2014 and we see an announcement for an improved DO technology, looking to deliver on the original promise of better, lighter, and smaller optics. While exciting, I’m here to talk about a technology that will change everything about how we think about imaging and optics.

Prior to DO, the incremental improvements of optics were made with new coatings, and development of lens materials with different refractive indexes. With DO, it was very exciting to have a material with an opposite effect on the light to the common optic materials, allowing you to directly correct the effects on the image.

Additive manufacturing (AM), commonly referred to as “3D Printing” is changing everything about how we develop and manufacture products across nearly every industry. Earlier this year I got to review optics (https://www.luxexcel.com) that were direct printed using a polymer jetting technique that creates lens drop by drop, much like an inkjet printer we as photographers are so intimately familiar with. These lenses come out of the printing process net shape, and are formed with a completely polished surface. While these lenses are made with plastics that are great optically (They’re equivalent to the materials used in modern camera phone lenses,) they’re not up to our standards for modern photographic lenses. However what these processes and equipment allow for is the ability to use arbitrary materials with arbitrary refractive indexes throughout the entire volume of the lens.

Imagine, this allows the lens designer to vary the path of the light not just for each angle of entry, but also for each specific frequency band. This would allow, theoretically, a single element that would correct all aberrations of a given optical system, allowing for thinner, lighter, and higher performance lenses than we’ve ever seen. This meta-material technology is capable of resolving light in ways completely impossible in classical optics systems. Combine with higher precision and more robust manufacturing capablities for diffractive systems, and you have everything you need to make a 600mm f/2.8 lens that weighs a kilogram or less. Or a distortion free 8mm rectilinear lens. Imagine that.

While I don’t think this technology will be ready for commercial use within the next few years, I do think it’s inevitable. Meta-materials have revolutionized all sorts of other industries, and I think optics is very likely one of the next.