The USMC is being a little bit coy here. After all they tested the concept of Augmented Integrated Team Training first. Getting the feel for "train as you fight", which was the idea from the beginning at TRADOC. AITT was developed by the Navy in conjunction with SA Photonics.

These Tactical Glasses Could Give Marine Grunts an F-35 Pilot's View of the Battlefield

SA Photonics is a small shop in Cali that has a history of innovation in optics. Unknown as well. Of late they seem to be coming out in the open a bit with their Chief Engineer doing interviews, updating their website, coming out with a non-military product. Besides AITT they did the re-design on the Helmet for F-35 among other devices, VR & AR. AITT became LARS (Low Cost AR System) and I'd wager that LARS (SA-62S) is and was the template for IVAS. The article calls it "F-35" for the grunt, OLED grunt, like it a lot better than the usual go-to Ironman reference. "F-35" has a better ring to it as the displays in that helmet (Kopin) are being replaced by AMOLED eMagin displays. At any rate, SA Photonics has always used eMagin displays. Look at their site. WUXGA in everything. SA Photonics was an attendee at the IVAS Industry day.  Was Microvision?

https://www.saphotonics.com/vision-products/augmented-reality/sa-62-s/

https://www.marines.mil/News/News-Display/Article/1031994/call-for-fire-marines-go-virtual

https://www.military.com/daily-news/2019/08/30/these-tactical-glasses-could-give-marine-grunts-f-35-pilots-view-battlefield.html