If you try searching for "smartphone augmented reality headset" on AliExpress you might still be able to find the thing I was using. It's been a few years since I did this. For its stated purpose the product is a rip-off since it's just overlaying a screen over your vision rather than creating an actual augmented reality effect, but I bought it specifically to do the thing I described and it worked great for that. That said, it was kind of cumbersome to set up and not exactly comfortable to wear for a long period of time, so not sure how practical I'd say it really is. That said, it did work great for being able to see the screen outside. Much better than the laptop's own screen.