What is the purpose of the convex lens in the eyepiece of a telescope?

The purpose of the convex lens in the eyepiece of a telescope is to converge rays so they will be directed to the eye. When light from distant objects enters the telescope, the convex lens acts by bending (or refracting) the incoming light rays. This refraction helps to focus the rays to form a clear image.

As the light rays converge, they create an enlarged view of the object being observed, making it possible for the eye to perceive the distant object with greater detail. The design of the eyepiece is crucial because it allows the viewer to see a well-defined image with minimal distortion.

While magnifying distant objects is a significant function of a telescope, the magnification effect does not occur directly because of the lens itself; it is a result of how the lens interacts with the optical arrangement of the telescope, including the objective lens. Other options like dispersing light evenly or filtering out unwanted wavelengths do not relate to the primary function of the eyepiece's convex lens, which is specifically about focusing light for the viewer's eye.