It may be a meniscus lens which is convex on one side and concave on the other, but it is thicker in the middle than the edges and functions like a convex lens. (The meniscus shape helps the lens focus light on a flat focal plane.) Higher quality lenses have multiple elements.
What is a diverging lens?
a lens that causes a beam of parallel rays to diverge after refraction, as from a virtual image; a lens that has a negative focal length.
Are microscope lenses concave or convex?
A reflecting telescope uses a concave mirror, a plane mirror, and a convex lens to do the same job. A microscope, like a reflecting telescope, uses a concave mirror, a plane mirror, and a convex lens. However, they are used to magnify very small images on slides not in the sky.
What are the use of convex lens?
Curving inward, concave lenses cause light to spread out, resulting in a smaller image for the viewer. Despite being less useful than convex lenses, concave lenses have several uses, including in eyeglasses and contacts, flashlights, peepholes, binoculars, telescopes, and in photography.