How to get clearer video output during webxr session (Chrome Canary 70.0.3538.2)?

Question

I am trying to get a clearer (near focused) video output from webxr session for recognizing text (using tesseract.js).

It looks like this now.

Things I have tried and failed

• Creating new camera session -> getusermedia during webxr session fails or crashes the browser
• Using existing session -> tried getting camera intrinsics(camera settings like focus) from webxr session (Read from an article that camera intrisics would disturb computer vision and therefore not available for now.)