Which three frame mounting types ensure lenses are fixed without eyewires or nylon cords?

The correct answer identifies the types of frame mountings that secure lenses without the use of eyewires or nylon cords, providing a specific structure for both aesthetics and function.

Rimless frames are designed so that the lenses are directly attached to the nose bridge and temple arms without any surrounding eyewire. This offers a minimalistic look while maintaining stability through the use of specialized mounting hardware.

Semi-rimless frames feature a design where only the top half of the lens is held in place by a frame, typically utilizing a nylon cord or a similar means of support at the bottom. However, they are often included in discussions concerning modern frame designs that emphasize lens stability without a full eyewire, allowing for a more open visual line.

Numont frames are characterized as being held in place primarily by a bridge and a single mounting point or the temple arms. This design effectively secures the lenses but does not involve traditional eyewires, reinforcing the focus on a streamlined appearance.

Together, these three frame mounting types embrace contemporary aesthetic trends while ensuring the lenses remain secure without the conventional eyewire or additional support methods.