Microsoft might well be enjoying a cosy relationship with Oculus VR these days, but that hasn't stopped one employee from picking holes in the headset's design. A freely downloadable CAD file has popped up online at Microsoft Research, with the group claiming to have developed a superior lens design than the one currently inhabiting the Oculus Rift DK2 headset.

According to the CAD project's readme file, the new lens design features a field of view that's "slightly smaller than the stock lens, but it is sharper across the field and has far less chromatic aberration." Example images show that the smaller field of view doesn't result in Hololens-like limitations, while also substantially improving the image quality.

The lens, which was developed by the a new "LensFactory program" at Microsoft Research, can be purchased from Edmund Optics, and the housing can be 3D printed using a high-end Objet Eden 260 3D printer. The readme file notes that the company hasn't tested any other printer, but that you may encounter "issues with hobbyist FDM printers, because the thin crush ribs that hold the lens elements in place may not print properly."

It also notes that you need to purchase lenses with a "visible light (VIS) antireflection coating," which ups the cost significantly. According to The Register, it works out at around £130 ($200) per eye. That might explain why the Oculus Rift DK2, which retails for $350 in total, doesn't use the aforementioned anti-reflection coating. That said, the consumer version of the Rift will apparently feature "custom optics" that may improve on lens distortion.

There's also another limitation to Microsoft's design aside from the price: it's tuned to work with the Unity game engine in order to correct lens distortion. Whether that's a permanent limitation or not remains to be seen, but the company has promised to publish a paper called "Lens Lego: Automatic Lens Generation Using Off-the-shelf Components" that will detail its work.