According to the https://www.ifixit.com/News/53272/nintendo-switch-oled-teardown-more-than-screen-deep the display is manufactured by Samsung.
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According to [link|https://www.ifixit.com/News/53272/nintendo-switch-oled-teardown-more-than-screen-deep|Nintendo Switch OLED Teardown: More Than Screen Deep|new_window=true] the display is manufactured by Samsung.