	US 12,092,851 B2
	Lighting device with a plurality of light guiding elements with increasing cross-sectional area to reduce divergency
Bernd Wölfing, Mainz (DE)
Assigned to SCHOTT AG, Mainz (DE)
Filed by SCHOTT AG, Mainz (DE)
Filed on Feb. 22, 2022, as Appl. No. 17/677,270.
Claims priority of application No. 10 2021 104 700.5 (DE), filed on Feb. 26, 2021.
Prior Publication US 2022/0276427 A1, Sep. 1, 2022
Int. Cl. F21V 8/00 (2006.01); F21W 106/00 (2018.01); F21W 107/30 (2018.01)

CPC G02B 6/0008 (2013.01) [F21V 2200/13 (2015.01); F21W 2106/00 (2018.01); F21W 2107/30 (2018.01)]

21 Claims

1. A lighting device, comprising:

a light source configured to emit primary light having a primary emission characteristic; and

an optical element having a light entry face and a light exit face, the optical element comprising a plurality of light guiding elements each forming part of the light entry face and part of the light exit face, the light entry face being configured to inject the primary light into the optical element, the plurality of light guiding elements each having a boundary surface extending between the light entry face and the light exit face, the boundary surface totally internally reflecting the primary light so that the light exit face emits a secondary light from the optical element,

wherein the optical element is configured to reduce a divergence of the primary light such that the secondary light has a secondary emission characteristic with an emission angle (β) that is smaller than an emission angle (α) of the primary emission characteristic,

wherein the plurality of light guiding elements each have a cross-sectional area at the light exit face that is larger than a cross-sectional area at the light entry face such that the light exit face is larger than the light entry face,

wherein the plurality of light guiding elements are bonded to one another or fused to one another, and

wherein the optical element comprises a widening section including a section having an increasing opening angle.