Abstract: A device including a nose pad configured to be placed on a nose of a user; and a first visual shield coupled to the nose pad and including a first plurality of hydraulic tubes radially spaced apart from each other and a light-blocking material therebetween, wherein the hydraulic tubes are configured to radially extend in response to hydraulic pressure to selectively restrict the user's peripheral visual field and consequently by elimination of the peripheral vision that distract the user result in increasing the user's concentration; and a hydraulic pump connected to the plurality of hydraulic tubes, the hydraulic pump being coupled to the nose pad and configured to provide hydraulic pressure for radially extending the first plurality of hydraulic tubes.

Abstract: A segmented annular tube is formed of a flexible material and includes an intussuscepted tube segment. The intussuscepted tube segment includes a core tube having a sheathed telescoping portion, surrounded by an inwardly folded sheathing portion of an outer tube. A pump selectively urges a fluid the segmented annular tube. Upon a fluid pressure, the folded sheathing portion unfolds and telescopes the core tube, expanding the segmented annular tube.

Abstract: A segmented annular tube is formed of a flexible material and includes an intussuscepted tube segment. The intussuscepted tube segment includes a core tube having a sheathed telescoping portion, surrounded by an inwardly folded sheathing portion of an outer tube. A pump selectively urges a fluid the segmented annular tube. Upon a fluid pressure, the folded sheathing portion unfolds and telescopes the core tube, expanding the segmented annular tube.

Abstract: A device including a nose pad configured to be placed on a nose of a user; and a first visual shield coupled to the nose pad and including a first plurality of hydraulic tubes radially spaced apart from each other and a light-blocking material therebetween, wherein the hydraulic tubes are configured to radially extend in response to hydraulic pressure to selectively restrict the user's peripheral visual field and consequently by elimination of the peripheral vision that distract the user result in increasing the user's concentration; and a hydraulic pump connected to the plurality of hydraulic tubes, the hydraulic pump being coupled to the nose pad and configured to provide hydraulic pressure for radially extending the first plurality of hydraulic tubes.