A light collection system (900, 1500, 2000), comprising: a light concentrating device (902, 1000, 2001), for receiving at least a portion of an incident light and forwardly emitting the portion of the incident light after concentrating and passing the portion of the incident light through a first focal region, so as to obtain a first-stage output light; and a reflective curving-surface device (904, 1002, 1036), having an entrance aperture for receiving at least the first-stage output light, wherein the reflective curving-surface device (904, 1002, 1036) comprises: a reflective inner curving surface having a second focal region, wherein the first focal region and the second focal region are confocal or confocal within a range so that at least one portion of the first-stage output light is confocally converted into a second-stage output light being forwardly emitted; and an exit aperture (906, 2008), configured to transmit at least the second-stage output light toward a target area where at least the second-stage output light is received; wherein the at least one portion of the first-stage output light is reflected by the reflective inner curving surface and emitted as the second-stage output light through the exit aperture (906, 2008); and wherein the light concentrating device (902, 1000, 2001) comprises a light collecting reflective curving surface having the first focal region; characterized in that the light concentrating device (902, 1000, 2001) also comprises a focusing element at a central region to receive a central-portion light of the incident light as a central concentrated light, wherein the focus of the focusing element overlaps the first and second focal regions, and wherein the distance between the focusing element and the target area is adjusted such that the focus of the light concentrating device is not on the target area, such that the central concentrated light is firstly passed through the first focal region before divergently reaching the target area. a light concentrating device (902, 1000, 2001), for receiving at least a portion of an incident light and forwardly emitting the portion of the incident light after concentrating and passing the portion of the incident light through a first focal region, so as to obtain a first-stage output light; and a reflective curving-surface device (904, 1002, 1036), having an entrance aperture for receiving at least the first-stage output light, wherein the reflective curving-surface device (904, 1002, 1036) comprises: a reflective inner curving surface having a second focal region, wherein the first focal region and the second focal region are confocal or confocal within a range so that at least one portion of the first-stage output light is confocally converted into a second-stage output light being forwardly emitted; and an exit aperture (906, 2008), configured to transmit at least the second-stage output light toward a target area where at least the second-stage output light is received; a reflective inner curving surface having a second focal region, wherein the first focal region and the second focal region are confocal or confocal within a range so that at least one portion of the first-stage output light is confocally converted into a second-stage output light being forwardly emitted; and an exit aperture (906, 2008), configured to transmit at least the second-stage output light toward a target area where at least the second-stage output light is received; wherein the at least one portion of the first-stage output light is reflected by the reflective inner curving surface and emitted as the second-stage output light through the exit aperture (906, 2008); and wherein the light concentrating device (902, 1000, 2001) comprises a light collecting reflective curving surface having the first focal region; characterized in that the light concentrating device (902, 1000, 2001) also comprises a focusing element at a central region to receive a central-portion light of the incident light as a central concentrated light, wherein the focus of the focusing element overlaps the first and second focal regions, and wherein the distance between the focusing element and the target area is adjusted such that the focus of the light concentrating device is not on the target area, such that the central concentrated light is firstly passed through the first focal region before divergently reaching the target area.