Reducing eye strain when displaying video in VR?

I'm working on a VR project where at some points we will display video in front of the user. I'm looking for recommendations/answers into how to maintain focus on the video without causing eye strain on the users. I want to know how others have tackled t$$anonymous$$s issue of showing video for VR headsets wit$$anonymous$$n their projects/games.

What I have tried so far is increasing/decreasing the size and distance of the video from the players eyes/head. I have found that since you can't do overlay or world space-camera with VR canvas, you have to result to general world space placement. T$$anonymous$$s results in decreasing too small and close causing a splitting effect and also blurring the video. Increasing the size as resulted in no significantly noticeable changes.

Headset: HTC Vive (Regular and Pro versions)