When the pantoscopic angle of a frame is increased, what adjustment must be made regarding the optical centers?

Increasing the pantoscopic angle of a frame means tilting the lenses forward at the bottom relative to the position of the ears. This adjustment affects how the lenses align with the eyes and can change the position of the optical centers relative to the eyes. When the pantoscopic angle is increased, the optical centers should be lowered to ensure they align correctly with the line of sight when the glasses are worn.

This is essential for maintaining proper vision because misalignment of the optical centers can lead to visual distortions or discomfort when wearing the eyewear. When optical centers are appropriately aligned with the wearer's pupils, the wearer is more likely to have a clear and comfortable field of vision.

In contrast, choices that suggest modifying the spherical equivalent or creating induced cylinder would not directly address the alignment issue created by changes to the pantoscopic angle. Raising the optical centers could exacerbate misalignment, leading to potential vision problems. Hence, correctly lowering the optical centers with an increase in the pantoscopic angle maintains optical performance.