When ordering a bifocal for a child, seg height should be raised.

• A. Raise
• B. Lower
• C. No change
• D. Raise by 0.5 mm

Answer: (A)

Raising the segment height is indicated because a child typically holds reading material closer and looks down more steeply when reading. By elevating the top of the bifocal segment, the near-vision portion falls into the child’s line of sight during normal downward gaze, allowing easy access to the reading addition without having to tilt the head excessively or look through the wrong part of the lens. If the segment is left at adult height—or set too low—the child may have to look through the distance portion or the edge of the segment, leading to blur, unwanted prism effects, and reduced effectiveness of the near addition. In practice, the seg height is increased from adult prescriptions to ensure the reading portion aligns with the child’s natural viewing posture and working distance as they grow.