Certified Ophthalmic Medical Technologist (COMT) Practice Exam

Is image jump more pronounced in which type of lenses with a near add segment?

1. Plus lenses

2. Minus lenses

3. Flat lenses

4. Multifocal lenses

The correct answer is: Minus lenses

Image jump is a phenomenon that occurs primarily with multifocal lenses, especially when transitioning between different segments such as from the distance portion to the near add segment. It refers to the noticeable shift in the position of the image when moving from one viewing area of the lens to another, which can be especially prominent in plus lenses due to their design and how they distribute power. In the case of minus lenses, especially in the examples where a near add is applied, the image jump is less pronounced. This is because minus lenses do not create as significant a power change when transitioning to the near segment compared to plus lenses, which can create a more abrupt transition due to the nature of their design and the way they bend light. In summary, the correct answer stems from the fact that the transition from the distance to the near segment can be more gradual with minus lenses than with plus lenses. While multifocal lenses encompass various designs, including both plus and minus configurations, the understanding of image jump dynamics is crucial, particularly in how power differences influence the perception of image displacement during close work.