Trifokal

Trifokal is a type of eyeglass lens designed to correct presbyopia by providing three distinct focal powers within a single lens: distance, intermediate, and near. This arrangement allows wearers to see clearly at far distances, office or computer viewing distances, and close work without switching between pairs.

Traditional trifocals have three areas separated by visible borders. The top portion provides distance vision, a middle zone supports intermediate tasks such as computer work, and a bottom segment offers near vision for reading. The exact sizes and placement of these zones vary with the lens design and frame geometry. Some newer versions use more subtle transitions or different segment shapes, but the classic fixed-zone trifocal retains three clearly defined focal levels.

Historically, trifocals were developed as an evolution from bifocals to address intermediate vision needs. They remain in use in some regions and for certain users, particularly where a fixed three-vision approach suits daily activities. However, many wearers now opt for progressive lenses, which provide a continuous change in power without distinct segments, offering more natural viewing across distances. Trifocals can be advantageous for those who prefer or require specific, clearly separated focal zones.

Materials and fitting considerations include plastic or polycarbonate lenses, coatings such as anti-reflective or scratch resistance, and accurate segment height and alignment to match the wearer’s pupil position. Proper prescription, frame choice, and professional fitting are essential to ensure comfortable vision and minimize image jumps between zones.