Stereo alignment assessment for head-mounted display

A head-mounted display system, comprising:

• a wearable frame assembly;
• a left display assembly mounted to a left side of the wearable frame assembly and configured to provide left-side display light and left-side test light;
• a left waveguide mounted to the left side of the wearable frame assembly and configured to incouple the left-side display light from the left display assembly and outcouple the left-side display light for viewing at a left eyebox;
• a left optical sensor positioned to measure the left-side test light proximate the left display assembly;
• a left inertial measuring unit (IMU) mounted to the left display assembly and configured to measure an orientation of the left display assembly;
• a right display assembly mounted to a right side of the wearable frame assembly and configured to provide right-side display light and right-side test light;
• a right waveguide mounted to the right side of the wearable frame assembly and configured to incouple the right-side display light from the right display assembly and outcouple the right-side display light for viewing at a right eyebox;
• a right optical sensor positioned to measure the right-side test light proximate the right display assembly;
• a right IMU mounted to the right display assembly and configured to measure an orientation of the right display assembly;
• and
• a logic machine configured to assess a stereo alignment for the left- and right-side display light based at least on the left-side test light measured by the left optical sensor, the right-side test light measured by the right optical sensor, the orientation of the left display assembly measured by the left IMU, and the orientation of the right display assembly measured by the right IMU.

A method for display system alignment assessment, the method comprising:

• at a left display assembly of a head-mounted display system, emitting left-side display light and left-side test light, the left-side display light incoupled by a left waveguide and outcoupled for viewing at a left eyebox;
• at a right display assembly of the head-mounted display system, emitting right-side display light and right-side test light, the right-side display light incoupled by a right waveguide and outcoupled for viewing at a right eyebox;
• measuring the left-side test light at a left optical sensor proximate to the left display assembly;
• measuring the right-side test light at a right optical sensor proximate to the right display assembly;
• assessing a left-side potential misalignment between the left display assembly and the left waveguide based at least in part on the left-side test light measured by the left optical sensor;
• assessing a right-side potential misalignment between the right display assembly and the right waveguide based at least in part on the right-side test light measured by the right optical sensor;
• and
• assessing a stereo alignment between the left display assembly and the right display assembly based at least in part on an orientation of the left display assembly measured by a left inertial measurement unit (IMU) coupled to the left display assembly, and an orientation of the right display assembly measured by a right IMU coupled to the right display assembly.