Apple Inc. (AAPL) has acquired a Denver, Colorado-based manufacturer of augmented reality lenses for an undisclosed sum.

The iPhone maker confirmed the purchase of Akonia Holographics to Reuters, but refrained from providing further details. “Apple buys smaller companies from time to time, and we generally don’t discuss our purpose or plans,” the company said in a statement. (See also: Apple AR Glasses an ‘Enormous’ Opportunity: Bernstein)

Apple’s acquisition of the startup offers the clearest indication yet that the Cupertino, California-based company is keen to develop a lightweight, wearable device that superimposes digital information over transparent lenses. Akonia, which was founded six years ago by a group of holography scientists, specializes in creating displays for augmented reality glasses.

On its website, the startup claims to have more than 200 patents related to holographic systems and materials, adding that its display technology allows for “thin, transparent smart glass lenses that display vibrant, full-color, wide field-of-view images.”

It is not yet known how much Apple is paying for Akonia or when the acquisition actually occurred. One executive in the augmented reality industry told Reuters that the startup had become “very quiet” over the past six months, suggesting that a deal may have been struck earlier in the year.

Apple Confirms AR Headset Ambitions

Speculation has been building for some time now that Apple is interested in developing augmented reality glasses. Last year, Bloomberg reported that the company could start shipping them as early as 2020.

In 2017, Apple CEO Tim Cook described augmented reality as a “big and profound” technology development after launching augmented reality applications for the iPhone and iPad. “This [augmented reality] is one of those huge things that we’ll look back at and marvel on the start of it,” Cook said in a conference call with investors last year, reported Reuters.

The acquisition of Akonia appears to confirm Apple’s headset ambitions, although it could be several years before the company comes out with its own piece of augmented reality hardware. The iPhone maker has a history of taking its time when introducing new technologies pioneered by the smaller companies it acquires. (See also: Apple Could Earn as Much as $8B From AR Apps: BofA.)

For example, it wasn’t until the iPhone was launched last year that PrimeSense’s three-dimensional sensors appeared in its products. Apple acquired the Israeli firm in 2013. (See also: Apple is a $1 Trillion Company. Now What?)

Other large tech firms are working on AR gear as well. Bose has promised smart glasses that focus on sound, Snap Inc. (SNAP) released Spectacles V2 in April, Microsoft Corp. (MSFT) is reportedly working on the next version of HoloLens and Facebook is currently conducting research.