Higher powered fundus lenses have what effect on field of view?

• A. Increased field of view
• B. Decreased field of view
• C. No change in field of view
• D. Field of view varies with distance

Answer: (A)

In indirect ophthalmoscopy, increasing the lens power increases the magnification of the retinal image. As you magnify more, you’re looking at a larger detail of a smaller area, so the portion of the retina visible through the lens at any moment becomes smaller. In other words, higher diopter lenses give more magnification but a tighter field of view. The trade-off is that you can see finer structures with greater detail, but you cover less of the retina at once. Conversely, lower power lenses provide a wider field of view with less magnification.