For a first-time wearer, at which reference point should a trifocal be fitted?

The fitting of trifocal lenses for a first-time wearer is typically done at the lower pupil margin. This reference point is crucial because trifocal lenses consist of three distinct optical zones: the top section for distance vision, the middle section for intermediate vision, and the lower section for near vision. By positioning the lower segment of the trifocal lens at the lower pupil margin, it ensures that the wearer will adequately align their near vision tasks, such as reading, with the correct optical zone of the lens.

Correct fitting is essential for optimal vision and comfort, especially for new users who may need time to adjust to multifocal lenses. If the trifocal is fitted too high or too low, it can lead to vision problems and discomfort. The preference for the lower pupil margin takes into account the natural resting position of the wearer when looking at reading material, making it the ideal fitting point to provide seamless transitions between different vision zones.