Contact lenses come in soft, rigid gas permeable (RGP), and hybrid types, categorized further by replacement schedules (daily, weekly, monthly) and vision correction needs (toric for astigmatism, multifocal for near/far vision, or colored/cosmetic). They also include specialty options like scleral for complex conditions and Ortho-K lenses to reshape the cornea overnight.
By Material & Design
- Soft Lenses: Most common, made of flexible plastic, comfortable quickly but absorb pollutants; include silicone hydrogel for better oxygen.
- Rigid Gas Permeable (RGP) Lenses: Harder, durable, allow good oxygen flow, offer sharp vision but need adaptation.
- Scleral Lenses: Large RGP lenses that rest on the white part (sclera) of the eye, good for irregular corneas.
- Hybrid Lenses: Combine a rigid center with a soft outer skirt for sharp vision and comfort.
By Replacement Schedule (Disposability)
- Daily Disposables: Wear once and discard; hygienic and convenient.
- Bi-Weekly/Monthly Disposables: Worn for longer periods, requiring cleaning and storage.
- Yearly (Conventional): Longest-lasting, requiring daily cleaning.
By Vision Correction
- Spherical: Correct nearsightedness (myopia) or farsightedness (hyperopia).
- Toric: Correct astigmatism with a cylindrical shape.
- Multifocal/Bifocal: Multiple prescriptions in one lens for near, intermediate, and distance vision (presbyopia).
- Monovision: One eye corrected for distance, the other for near.
Specialty Lenses
- Cosmetic/Colored: Change or enhance eye color, available with or without prescription.
- Orthokeratology (Ortho-K): Worn overnight to temporarily reshape the cornea, reducing daytime need for glasses/contacts.
- Extended Wear: Approved for overnight wear (up to 30 days for some types).