When light passes through the clear, front window of the eye (cornea), it is focused on the inner lining of the eye (retina). Here’s an analogy (See Figure 1): think of the cornea as a movie projector, with the retina as a projector screen. The projector and the screen are 20 feet apart, and the projector casts its image 20 feet away onto the screen. The result is a clear image.
A nearsighted eye is longer, which causes light to focus in front of the retina instead of directly on it, leading to a blurry image (Figure 2). Imagine the projector casting an image 20 feet away, but with the projector screen now sitting 25 feet away, which leads to a blurry, out-of-focus picture.

When light passes through the clear, front window of the eye (cornea), it is focused on the inner lining of the eye (retina). Here’s an analogy (See Figure 1): think of the cornea as a movie projector, with the retina as a projector screen. The projector and the screen are 20 feet apart, and the projector casts its image 20 feet away onto the screen. The result is a clear image.

A nearsighted eye is longer, which causes light to focus in front of the retina instead of directly on it, leading to a blurry image (Figure 2). Imagine the projector casting an image 20 feet away, but with the projector screen now sitting 25 feet away, which leads to a blurry, out-of-focus picture.
