Which of the following is NOT a way to raise the bifocal seg height of spectacles?

• A. Increase pantoscopic tilt
• B. Narrow the pads
• C. Shrink the bridge
• D. Increase the vertex distance

Answer: (A)

Raising the bifocal seg height depends on how the frame sits relative to the eye and how far the lenses sit from the eye. To move the near portion higher on the lens, you adjust fit in ways that bring the frame closer to the eye or adjust the lens’s distance from the eye, so the eye’s line of sight intersects a higher region of the lens.

Increasing pantoscopic tilt rotates the frame about the horizontal axis but doesn’t change the vertical position of the segment on the lens itself. It can alter the viewing angle and how you perceive through the near portion, but it doesn’t raise the actual height of the bifocal segment. In contrast, narrowing the pads or shrinking the bridge pulls the frame closer to the nose, which effectively raises the segment height in the wearer's line of sight. Increasing the vertex distance moves the lens away from the eye, causing the eye to look through a higher part of the lens, also raising the segment.

So, pantoscopic tilt does not raise the bifocal seg height, while the other adjustments can.