Squares in left and right lens of HMD were perceived separatellyy

[jacky]

Hi all,

Can anyone help me? When I drew a small square in the center of the screen, I saw two squares by wearing a HMD. In other words, the squares in left and right eye were perceived separately, not superimposed . But when I reversed the stereo by sending a negative interpupilary distance, the squares appeared to be one. I could perceived it normally. I can't find the reasons. If someone know, please tell me. Thanks a lot.