Answer:
A convex lens bulges in the middle.
Explanation:
Lenses are homogeneous and transparent materials in which at least one face must have a curvature, however some lenses have curvature on both sides. Depending on the type of curvature, the lenses can be: convex or concave lenses.
Convex lenses are thin-rimmed lenses. The central part is thicker. These lenses stand out in the middle and usually deflect the light passing through them in the other direction.
