Vcsel and vcsel chip with small divergence angle and light source for lidar system

Abstract

A VCSEL includes a lower Bragg reflection layer, an active layer and an upper Bragg reflection layer. The active layer is located on a side of the lower Bragg reflection layer. The upper Bragg reflection layer is located on a side of the active layer away from the lower Bragg reflection layer. A current limiting layer is disposed inside or outside the active layer, and the current limiting layer has an opening for defining a light-emitting region. An extended cavity layer is disposed at least between the lower Bragg reflection layer and the active layer or between the upper Bragg reflection layer and the active layer, the extended cavity layer includes at least one resonant cavity inside, and the at least one resonant cavity is configured to increase the optical field intensity in the extended cavity layer.

Dependencies are inferred from the claim text.