External camera calibration for smart glasses

Hello,

I'm developing AR application for Epson BT-35E smart glasses. I wrote external camera driver and can find image coordinates on top of video stream. Now I need to find target coordinates in see-through mode and place a marker on object in real world. As I understand I need to go through camera calibration procedure and use the result of this procedure in external camera driver.

I checked this article https://library.vuforia.com/platform-support/external-camera-calibration and I have a question - Is this article suitable for smart glasses? As far as I understand, to project some point in real world, I need to specify some sort of angle between the camera and user eyes. But in the article we just taking a photos and we don't get any information about camera position relative to user eyes. May be I need another kind of calibration for glasses? Could you help me with some advice?

Also could you give me some example of calibration tool, which works on Android platform and which results are suitable for Vuforia?