The technical meaning of HPU  is  holographic processing unit

The technical meaning of IMU  is  inertial measuring unit

The technical meaning of IoT  is  internet of things

The technical meaning of IPD  is  interpupillary distance

The technical meaning of IR is infrared

The technical meaning of LoS  is  line of sight

The technical meaning of MR  is  Mixed Reality

The technical meaning of OHMD  is  optical head-mounted display

The technical meaning of AR is  augmented reality

The technical meaning of PPI  is pixels per inch