The VPL EyePhone HRX is a head-mounted display for VR made by VPL. It has flat focus.
It used a Polhemus tracker for 3D tracking.[1][2]
It cost a whopping $49,000.[1]
Its resolution is a total of 345,600 subpixels per eye.[2]
Its single-eye field of view is about 86 degrees horizontal by 75 degrees vertical. Its total two-view FOV is horizontally about 106 degrees.[1]