What is the name of the lens mounting that uses one screw at the bridge area to attach each lens?

The correct answer is Numont mounting, which refers to a specific type of lens mounting where each lens is attached with a single screw at the bridge area. This style is characterized by its minimalistic design that does not feature a full rim to encase the lenses. Instead, the lenses are held in place primarily through this screw mechanism, allowing for a lightweight and unobtrusive appearance.

Rimless mounting typically involves a design where the lenses are held solely by a frame without any rim, but it often employs multiple screws or a more complex mounting system, making it distinct from the simplicity of Numont mounting. Semi-rimless mounting incorporates a partial frame that holds the lower part of the lens while allowing the upper part to remain exposed; however, this method usually requires more than just one screw at the bridge. Therefore, these options do not accurately describe the unique one-screw fastening characteristic of Numont mounting.