Lens and lens assembly

Provided are a lens and a lens assembly. The lens includes a first surface, a second surface opposite to the first surface, and a connection surface connecting the first surface with the second surface. The connection surface includes a first outer edge surface, a second outer edge surface, and a third outer edge surface. The first to third outer edge surfaces are all inclined towards an optical axis, at least one has an inclination angle larger than or equal to 10° and smaller than 60°, and at least another one has an inclination angle larger than 0° and smaller than 10°. Alternatively, at least one of the first to third outer edge surfaces is parallel to the optical axis, the other two are inclined towards the optical axis and include at least one having an inclination angle larger than or equal to 10° and smaller than 60°.