Embodiments are directed to eyewear. The eyewear may include a frame, a left cord, a right cord, and an adjustable coupler. The frame may have a left end piece and a right end piece. Each of the left and right end pieces may have one or more apertures. The left cord has a proximal end portion and a distal end portion. The proximal end portion of the left cord may extend through at least one of the one or more apertures in the left end piece. The right cord has a proximal end portion and a distal end portion. The proximal end portion of the right cord may extend through at least one of the one or more apertures in the right end piece. The adjustable coupler may couple the left cord to the right cord.

A method of calculating an optical system (OS) of an ophthalmic lens according to a given spectacle frame, said ophthalmic lens comprising a back surface (BS) and a front surface (FS) arranged to deliver an ophthalmic vision image (VI), a light-guide optical element having a proximal surface (PS) and a distal surface (DS), said light-guide optical element being arranged to output a supplementary image (SI), wherein the method comprises the steps of: providing at least a morpho-geometrical parameter data of the frame or of the light-guide optical element; optimizing the optical system (OS) according to at least the morpho-geometrical parameter data as a target.

A surgical loupes head strap is disclosed. The surgical loupes head strap may include a first monofilament and a second monofilament coupled by at least one sleeve. The surgical loupes head strap may further include a first coupler with a first hole and a second hole, where the first hole is configured to surround and couple to a first end of the first monofilament, and the second hole is configured to surround and couple to at least a portion of a first surgical loupes headgear temple. The surgical loupes head strap may further include a second coupler with a first hole and a second hole, where the first hole is configured to surround and couple to a first end of the second monofilament, and the second hole is configured to surround and couple to at least a portion of a second surgical loupes headgear temple.

Eyewear devices including a tether and methods for identifying proper installation of the tether are disclosed. An eyewear device includes transmission lines extending through the temples to electrical and electronic components positioned adjacent to edges of a frame. A tether is attached to the temples to enable power and communication flow between the electrical and electronic components rather than through the frame. Proper installation is identified based on communications passing between the electrical and electronic components via the tether.

An adjustable eyewear restraint comprises a first strap having a first adjustment end and a first eyewear coupling end, and a second strap having a second adjustment end and a second eyewear coupling end. The straps are slidably and frictionally engageable to one another to allow adjustment of a length of the restraint by moving adjustment ends of the straps relative to each other. The straps can be slidably interwoven to each other about opening(s) of respective adjustment ends. The opening(s) slidably receive an opposing strap. A strap has a loop, coupleable to eyewear, that comprises first and second edges attached together to form an attachment portion substantially in-line with the first edge. A frictional element is frictionally and slidably coupleable to an earpiece to retain the loop and allow adjustment of a length of an eyewear retainer. Associated systems and methods are provided.

The eyeglasses includes a glasses frame and two temples. The glasses frame has two opposite ends. Each of the two temples has a front end connected pivotally to a respective one of the two opposite ends of the glasses frame. Each of the two temples have a section that is flexible so that, by applying lateral forces to the two temples, the temples are convertible between an outwardly curved state where rear ends of the two temples are spaced apart from each other at a first distance, and an inwardly curved state where the rear ends of the two temples are spaced apart from each other at a second distance that is smaller than the first distance.

A magnetic attraction type lens-replaceable eyeglasses, comprising a frame and lenses. A connector for fixedly connecting the lenses to the frame is disposed at a bridge of the frame. The connector is detachably connected to the frame. The connector and the frame are in magnetic attraction cooperation. Fixing pins capable of penetrating through the lenses and used for limiting the swing of the lenses are disposed on the side, in contact with the lenses, of the connector. By using the detachable connector, the lenses are fixed to the frame. By means of magnetic attraction cooperation, the lenses can be relatively easy to replace. Meanwhile, by using a design of positioning pins, it can be ensured that the lenses mounted on the frame will not swing or shift.

A magnetic attraction type lens-replaceable eyeglasses, comprising a frame and lenses. A connector for fixedly connecting the lenses to the frame is disposed at a bridge of the frame. The connector is detachably connected to the frame. The connector and the frame are in magnetic attraction cooperation. Fixing pins capable of penetrating through the lenses and used for limiting the swing of the lenses are disposed on the side, in contact with the lenses, of the connector. By using the detachable connector, the lenses are fixed to the frame. By means of magnetic attraction cooperation, the lenses can be relatively easy to replace. Meanwhile, by using a design of positioning pins, it can be ensured that the lenses mounted on the frame will not swing or shift.

A head-mounted display to be worn by a user includes a housing, and an eye chamber to be positioned adjacent to eyes of the user. A support assembly includes a headband and an adjustment mechanism that is operable to change fit of the headband relative to the head of the user in response to a control signal, wherein the adjustment mechanism includes a feedback component, and the control signal is generated based on output from the feedback component.

Eyewear for releasably receiving a lens has a joint sleeve for holding the lens in place.