These are my mom’s reading glasses and they contain many pairs of skew lines. It has two frames, for the eyes to see through, and then two thin “poles” that hold the glasses on her ears. The vertical line of the frame is in a different plane and never intersects with the thin “pole” that goes behind the ear. After my mom set her glasses down, I saw the pairs of skew lines such as a vertical frame line to a “pole” line, and the same thing on the other side. This specific way that the shape of glasses are made provides the most comfort and functionality of whoever is wearing them. Therefore, if the glasses only had horizontal lines, there would be no skew lines, and no way to possibly wear those glasses. The structure of glasses has worked for many years and will continue to work, even as we reach new inventions such as the HoloLens.
