Abstract: Some embodiments are directed to retrofitting apparatus for use with a chair, the chair including a seat portion, a back portion that extends substantially perpendicular to the seat portion, and at least one elongated connector that connects the seat portion and the back portion. The retrofitting apparatus includes a removable coupling structure connectable to the at least one elongated connector of the chair, the removable coupling structure including at least one connecting member configured to extend around a perimeter of a portion of the at least one elongated connector; and a cover connected to the coupling structure, the cover configured to project from at least a 180 degree radius around at least a portion of the back portion of the chair, thereby extending around sides of a chair occupant so as to provide a physical barrier between the chair occupant and those disposed adjacent thereto.

Abstract: A carrier holds an extreme ultraviolet light source collector mirror. The carrier includes a front panel having an inner surface and an outer surface opposite the inner surface, and defining a through opening that has an edge having a plurality of scallops; a back panel having an inner surface that faces the front panel and an outer surface opposite the inner surface; and a plurality of posts that are configured to connect the back panel to the front panel and to sandwich a flat rim around the circular boundary of the collector mirror between the inner surface of one of the panels and flanges of the posts. The scallops are positioned around a circumference of the edge and being separated by arcs, where the arcs define a circle that has a diameter that is less than a diameter of the circular boundary of the reflective surface of the collector mirror.

Abstract: A tool is used in securing or clamping two or more workpieces together provides a visual indication to a user of the tool of an acceptable range of compression pressure exerted by the tool on a work surface of the workpieces and a visual indication of when a maximum compression pressure exerted by the tool on the work surface has been exceeded.

Abstract: A bar clamp having a ratchet for fastening a clamped work piece is provided with a fixed jaw carrier at a front end of a slide bar; a moveable jaw carrier moveably put on the slide bar and including a transverse channel distal the slide bar, and a gear adjacent to the channel; a shaft partially disposed in the channel and including two parallelepiped ends; two cam members each including a rectangular hole complimentarily put on one parallelepiped end; a control lever including two fitting members disposed in tunnels and each including a rectangular hole complimentarily put on one parallelepiped end, a pivot hole, and a pin; a ratchet assembly including a spring actuated trigger mounted on the control lever, and a link secured to the trigger and including a pawl member in gear engagement with the gear; and a bifurcation member including two opposite curved slots.