The Pixel 3 uses a Samsung screen.
Pixel 3 XL is a Samsung screen, but Pixel 3 is LG. And there's a noticeable improvement in the display, beyond PPI, when comparing the two. Pixel 3 has grainy colors, but the 3 XL doesn't.
https://www.ifixit.com/Teardown/Google+Pixel+3+Teardown/113763
After finding a Samsung-made OLED display in the larger Pixel 3 XL, we dissected the display in our vanilla Pixel 3. Surprise—it's from LG Display!