Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What happens to the image jump effect when gaze is shifted from distance to the near add segment?

1. It improves

2. It causes discomfort

3. It remains stable

4. It reduces clarity

The correct answer is: It causes discomfort

When shifting gaze from distance to the near add segment in multifocal or bifocal lenses, the image jump effect can indeed cause discomfort. This phenomenon occurs because there is a noticeable change in the position of the image due to the different optical powers of the lens segments. When a person looks through the distance portion, the image may appear at a particular level of clarity and position. However, when they transition to the near segment, the jump can create sudden shifts in image position, size, and clarity, which may not feel natural to the visual system. This effect may lead to visual discomfort as the eyes attempt to accommodate for the sudden change in image location and focus. The brain must quickly adjust to the new visual input, which can be jarring and potentially disorienting. Additionally, the adjustment process can lead to fatigue or strain as the visual system tries to cope with the abrupt transition. In contrast, it is less likely for the image jump effect to improve, remain stable, or reduce clarity without causing discomfort, as there will always be some level of adjustment required when switching from one focal area of a lens to another. Thus, the discomfort experienced is a significant aspect of the experience for users of multifocal lenses when making such shifts in gaze.