Abstract: A head-mounted device may include a main housing portion with displays that display images and optical modules through which the images are viewable from eye boxes. A light seal may be coupled to the main housing portion and may surround the eye boxes to prevent outside light from reaching the viewing area of the head-mounted device. The light seal may include inner and outer fabric layers. The outer fabric layer may be a seamless tube of knit fabric. The inner fabric layer may be an opaque fabric that lines the inner surface of the outer fabric layer. The outer fabric layer may have a modified bird's eye pattern that incorporates alternating knit stitches and tuck stitches. The tuck stitches allow the outer fabric layer to stretch in the lengthwise direction of the fabric to prevent buckling when the light seal is pressed against the user's face.

Abstract: A head-mounted device may include a housing with a display that displays images that are viewable from an eye box. A light seal may be coupled the housing and may block outside light from reaching the eye box. The light seal may include a seamless tube of knit fabric that forms an outermost layer of the light seal. A light-blocking fabric may line the inner surface of the seamless tube of knit fabric. The light-blocking fabric may include a dark-colored weft knit layer facing the eye box, a light-colored weft knit layer facing and matching a color of the seamless tube of knit fabric, and a middle layer joining the light-colored weft knit layer and the dark-colored weft knit layer. The dark-colored weft knit layer may ensure sufficient opacity without being visible through the seamless tube of knit fabric.

Abstract: Electronic devices such as head-mounted electronic devices may include displays for presenting images to users. To accommodate variations in the interpupillary distances associated with different users, a head-mounted device may have left-eye and right-eye optical modules that move with respect to each other. To hide internal structures from view, the rear of a head-mounted device may be provided with a cover. The cover may have a stretchable layer that is coupled to a frame. Openings in the stretchable layer may be aligned with the optical modules.

Abstract: A head-mounted device may include a main housing portion and displays in the main housing portion that provide images to eye boxes. A light seal may be coupled to the main housing portion and may at least partially surround the eye boxes. The head-mounted device may include sweat mitigation structures such as moisture-guiding channels in the light seal to guide sweat and other moisture away from the eye boxes. The moisture-guiding channels may be formed from grooves or moisture-wicking fabric. Control circuitry may adjust a fan based on humidity, temperature, or fog detected by a sensor. The light seal may include a directional pattern of grooves through which moisture is guided away from the eye boxes. A moisture barrier layer may be interposed between an inner foam layer and an outer light-blocking fabric to prevent sweat from penetrating into the foam.

Abstract: A head-mounted device may include a main housing portion and a temple housing portion. Displays in the main housing portion may be configured to present images that are viewable from eye boxes. A light-blocking cover may extend between the main housing portion and the temple housing portion and may be configured to prevent outside light from reaching the eye boxes. The light-blocking cover may have a stretchable outer fabric layer and an inner light-blocking layer formed from fabric or other suitable materials. The light-blocking cover may include slack in the inner light-blocking layer so that the inner light-blocking layer can accommodate movement of the main housing portion relative to the temple housing portion without sacrificing opacity. The slack may be heat-set, molded, or covered with a layer of elastic so that the slack returns to a retracted state within the temple housing portion after being expanded.

Abstract: Electronic devices such as head-mounted electronic devices may include displays for presenting images to users. To accommodate variations in the interpupillary distances associated with different users, a head-mounted device may have left-eye and right-eye optical modules that move with respect to each other. To hide internal structures from view, the rear of a head-mounted device may be provided with a cover. The cover may have a stretchable layer that is coupled to a frame. Openings in the stretchable layer may be aligned with the optical modules.

Abstract: Electronic devices such as head-mounted electronic devices may include displays for presenting images to users. To accommodate variations in the interpupillary distances associated with different users, a head-mounted device may have left-eye and right-eye optical modules that move with respect to each other. To hide internal structures from view, the rear of a head-mounted device may be provided with a cover. The cover may have a stretchable layer that is coupled to a frame. Openings in the stretchable layer may be aligned with the optical modules.