BI-STABLE BUCKLE

1 . An adjustable buckle, comprising:

a first plate configured to secure to a portion of a head strap;

a second plate configured to secure to a head-mounted display;

at least one guide member extending between the first plate and the second plate, at least one of the first plate and the second plate slidably movable along the guide member to place the adjustable buckle in a first stable mode or to place the adjustable buckle in a second stable mode, a distance between the first plate and a second plate larger in the first stable mode relative to the second stable mode;

a third plate bendably connected to the first plate or the second plate via a first flexible hinge at a first end; and

a fourth plate between the third plate and the second plate or the first plate, the fourth plate having a first end bendably connected to a second end of the third plate via a second flexible hinge and a second end bendably connected via a third flexible hinge to the second plate or the first plate, a surface of the fourth plate coming into contact with the third plate in the second stable mode, the surface of the fourth plate coming into contact with the second plate or the first plate in the first stable mode.

2 . The adjustable buckle of claim 1 , wherein the at least one guide member is housed within a passage of the first plate.

3 . The adjustable buckle of claim 1 , wherein the at least one guide member is secured within the first plate or the second plate.

4 . The adjustable buckle of claim 1 , wherein the third plate comprises a plurality of protruding tabs.

5 . The adjustable buckle of claim 4 , wherein when a user exerts a force on the plurality of protruding tabs in a direction away from a side of the head-mounted display to which the adjustable buckle is attached, the adjustable buckle is released from its stable mode.

6 . The adjustable buckle of claim 1 , wherein the first flexible hinge and the second flexible hinge are configured to rotate at least 180 degrees.

7 . The adjustable buckle of claim 1 , wherein the third plate slidably moves along the at least one guide member in synchronous motion with rotation of the fourth plate about the second flexible hinge and the third flexible hinge.

8 . The adjustable buckle of claim 1 , wherein the first plate, second plate, third plate, and fourth plates are integrally formed of the same material.

9 . An adjustable buckle for coupling a head strap and a head-mounted display, the adjustable buckle comprising:

a first plate configured to secure a portion of the head strap;

a second plate configured to secure a portion of the head-mounted display;

at least one guide member extending between the first plate and the second plate;

a linked plate between the first plate and the second plate, the linked plate having a first end bendably connected to a second end of the first plate via a first flexible hinge and a second end bendably connected via a second flexible hinge to the second plate, at least a portion of the linked plate positioned along the at least one guide member and slidably movable to place the adjustable buckle in a first stable mode or in a second stable mode, a distance between the first plate and a second plate larger in the first stable mode relative to the second stable mode.

10 . The adjustable buckle of claim 1 , wherein the at least one guide member is housed within a passage of the first plate.

11 . The adjustable buckle of claim 1 , wherein the at least one guide member is secured within the first plate or the second plate.

12 . The adjustable buckle of claim 1 , wherein the linked plate comprises a plurality of protruding tabs.

13 . The adjustable buckle of claim 4 , wherein when a user exerts a force on the plurality of protruding tabs in a direction away from a side of the head-mounted display to which the adjustable buckle is attached, the adjustable buckle is released from its stable mode.

14 . The adjustable buckle of claim 1 , wherein the first flexible hinge or the second flexible hinge are configured to rotate at least 180 degrees.

15 . The adjustable buckle of claim 1 , wherein the linked plate slidably moves along the at least one guide member in synchronous motion with rotation of the linked plate about the second flexible hinge.

16 . The adjustable buckle of claim 1 , wherein the first plate, second plate, and linked plate are integrally formed of the same material.

17 . An eyewear comprising:

a front rigid body;

a head strap; and

an adjustable buckle, comprising:

a first plate configured to secure to a portion of the head strap,

a second plate configured to secure to the front rigid body,

at least one guide member extending between the first plate and the second plate, at least one of the first plate and the second plate slidably movable along the guide member to place the adjustable buckle in a first stable mode or to place the adjustable buckle in a second stable mode, a distance between the first plate and a second plate larger in the first stable mode relative to the second stable mode,

a third plate bendably connected to the first plate or the second plate via a first flexible hinge at a first end, and

a fourth plate between the third plate and the second plate or the first plate, the fourth plate having a first end bendably connected to a second end of the third plate via a second flexible hinge and a second end bendably connected via a third flexible hinge to the second plate or the first plate, a surface of the fourth plate coming into contact with the third plate in the second stable mode, the surface of the fourth plate coming into contact with the second plate or the first plate in the first stable mode.

18 . The eyewear of claim 17 , wherein the at least one guide member is housed within a passage of the first plate.

19 . The eyewear of claim 17 , wherein the at least one guide member is secured within the first plate or the second plate.

20 . The eyewear of claim 17 , wherein the third plate comprises a plurality of protruding tabs.