A light collection system including a light concentrating device and a reflective curving-surface device is provided. The light concentrating device receives at least a portion of an incident light and forwardly emits the portion of the incident light after concentrating and passing it through a first focal region, so as to obtain a first-stage output light. The reflective curving-surface device has an entrance aperture for receiving the first-stage output light. The reflective curving-surface device includes a reflective inner curving surface, and at least a portion of the reflective inner curving surface has a second focal region. The first focal region and the second focal region are confocal or approximately confocal within a range. As a result, at least a portion of the first-stage output light is confocally converted into a forwardly emitted second-stage output light.