BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate a number of exemplary embodiments and are a part of the specification. Together with the following description, these drawings demonstrate and explain various principles of the present disclosure.

FIG. 1shows a voided polymer material including a periodic array of voids.

FIG. 2shows an apparatus configured to stretch a material layer along one direction.

FIG. 3shows an apparatus configured to stretch a material layer supported by a substrate along one direction.

FIG. 4is a side view that illustrates a material layer stretched transversely.

FIG. 5shows a material layer between a pair of layers, which are then stretched.

FIG. 6shows a top view of an example transverse stretcher.

FIG. 7shows an example of a sequential biaxial stretcher.

FIG. 8shows an example of a sequential biaxial stretcher.

FIG. 9is a top view of a uniaxial stretcher.

FIG. 10shows a top view of a biaxial stretcher.

FIG. 11illustrates formation of anisotropic voids using a pressure applied to the top surface of a material layer.

FIGS. 12A-12Bshow formation of anisotropic voids using a pressure chamber.

FIGS. 13A-13Bshow formation of anisotropic voids using an electric field applied to a material layer.

FIG. 14shows a cross-section of a material layer formed on a substrate.

FIG. 15shows a cross-section of a material layer formed on a substrate supported by a conveyor belt.

FIGS. 16A-16Bshow how shaped voids may be formed using fluid evaporation.

FIGS. 17 and 18illustrate example methods of forming a voided polymer material.

FIG. 19illustrates an example control system.

FIG. 20is an illustration of exemplary augmented-reality glasses that may be used in connection with embodiments of this disclosure.

FIG. 21is an illustration of an exemplary virtual-reality headset that may be used in connection with embodiments of this disclosure.

FIG. 22is an illustration of exemplary haptic devices that may be used in connection with embodiments of this disclosure.

FIG. 23is an illustration of an exemplary virtual-reality environment according to embodiments of this disclosure.

FIG. 24is an illustration of an exemplary augmented-reality environment according to embodiments of this disclosure.

Throughout the drawings, identical reference characters and descriptions indicate similar, but not necessarily identical, elements. While the exemplary embodiments described herein are susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, the exemplary embodiments described herein are not intended to be limited to the particular forms disclosed. Rather, the present disclosure covers all modifications, equivalents, and alternatives falling within the scope of the appended claims.

