Which contact lens features a prescription in the center for distance with alternating rings of power surrounding it?

• A. Concentric Multifocal Lens
• B. RGP's Toric
• C. Multifocal Concentric
• D. Toric Lenses

Answer: (A)

The concentric multifocal lens is designed with a central area that provides correction for distance vision, surrounded by alternating rings of different powers to address near and intermediate vision. This unique design allows the wearer to transition smoothly between viewing distances, making it particularly beneficial for individuals who need multifocal correction but prefer a lens that provides a consistent visual experience as they shift their gaze.

In concentric multifocal lenses, the alternating rings facilitate gradual changes in power, allowing for better focus at various distances without having to change lenses. This is unlike a traditional multifocal lens which may utilize a gradient or progressive design.

The other options, while related to lens designs, do not specifically describe the structure of the concentric multifocal lens. RGP's toric lenses focus on astigmatism correction, while toric lenses generally provide specific shaping to correct astigmatism without incorporating the multifocal design characteristic of concentric lenses. Multifocal concentric is a term that could seem similar but may not accurately reflect the design mentioned in this question. Thus, the selection of the concentric multifocal lens aligns with the question's requirements for distance correction integrated into its design.