Optical eye tracking systems and methods

A head-mounted display (HMD) system, comprising:

• a support structure wearable on the head of a user;
• first and second eye tracking subsystems coupled to the support structure, each of the first and second eye tracking subsystems comprising:
• a lens assembly;
• an optical tube assembly mechanically coupled to the lens assembly to support the lens assembly and to provide optical alignment between the lens assembly and a display panel of the HMD system, the lens assembly being positioned proximate to a front end of the optical tube assembly that is relatively proximate a user's eye during use of the HMD system;
• and
• an optical light guide operative to transport light, the optical light guide being mechanically coupled to the optical tube assembly, the optical light guide comprising:
• a light input feature that is positioned rearward of the front end of the optical tube assembly, the light input feature configured to receive light from one or more light sources;
• and
• a plurality of light output features spaced apart from each other and positioned proximate to the front end of the optical tube assembly, each of the light output features configured to allow light inside the optical light guide to exit the optical light guide toward the user's eye during use of the HMD system.

A method for manufacturing an optical tube assembly, the method comprising:

• positioning a mold within a dual-shot injection molding apparatus, the mold having a cavity defining the shape of an optical tube assembly;
• injecting a first material into a mold cavity using a first injection unit, the first material configured to form a portion of the optical tube assembly and having properties suitable for structural support;
• injecting a second material into the mold cavity using a second injection unit, the second material configured to form an optical light guide;
• and
• allowing the second material to solidify within the mold cavity, thereby fusing the first and second materials to form the optical tube assembly as a single, integrated component.

An eye tracking system for a head-mounted display (HMD) device, comprising:

• a lens assembly;
• an optical tube assembly mechanically coupled to the lens assembly to support the lens assembly and to provide optical alignment between the lens assembly and a display panel of the HMD device, the lens assembly being positioned proximate to a front end of the optical tube assembly that is relatively proximate a user's eye during use of the HMD device;
• and
• an optical light guide operative to transport light, the optical light guide being mechanically coupled to a sidewall of the optical tube assembly, the optical light guide comprising:
• one or more light input features that are positioned rearward of the front end of the optical tube assembly, each of the one or more light input features configured to receive light from one or more light sources;
• and
• one or more light output features positioned proximate to the front end of the optical tube assembly, each of the one or more light output features configured to allow light inside the optical light guide to exit the optical light guide toward the user's eye during use of the HMD device.