US 12,066,652 B2
Function display for selectively displaying several symbols that respectively represent a switching function and/or several switching states, with an alignment function of the light sources, and associated assembly method
Wolfgang Schustek, Eichenhausen (DE); and Michael Benkert, Saal an der Saale (DE)
Assigned to Preh GmbH, Bad Neustadt a.d. Saale (DE)
Filed by Preh GmbH, Bad Neustadt a.d. Saale (DE)
Filed on Jun. 15, 2022, as Appl. No. 17/807,042.
Prior Publication US 2022/0404542 A1, Dec. 22, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. F21V 8/00 (2006.01); G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G02B 6/0076 (2013.01) [G02B 6/0021 (2013.01); G02B 6/0043 (2013.01); G02B 6/0065 (2013.01); G02B 6/0068 (2013.01); G02B 6/0073 (2013.01); G02B 6/0083 (2013.01); G02B 6/0088 (2013.01); G06F 3/0412 (2013.01); G06F 3/044 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A function display for selectively displaying several symbols representing one switching function, respectively, and/or at least two switching states, respectively, in particular for a motor vehicle, comprising:
a light guide stack which, given an attachment of the function display, forms a display surface facing towards an observer; wherein the light guide stack is formed from at least two transparent or translucent planar light guides arranged in an overlaid manner in a stacking direction, which are arranged so as to be spaced apart by a transparent or translucent layer including a material that is optically thinner compared to the adjacent planar light guides so that the planar light guides each have a main surface facing towards the observer and a main surface facing away from the observer, and, in at least one light guide of the planar light guides, the main surface facing away from the observer faces towards another at least one light guide of the planar light guides which is most closely adjacent in the opposite direction to the stacking direction;
at least one light source for each planar light guide, which is arranged such that in each case, its light, via an end face of an associated light guide facing towards the light source, is coupled into the respective light guide;
wherein, further, at least one microstructured symbol area provided in or on the planar light guide is provided for each planar light guide, which includes several light-refractive and/or light-scattering microstructures and is configured, if the at least one light source is respectively activated, to be visible, illuminated by the light coupled into the planar light guide, to the observer, in order to display to the observer a symbol composed of the at least one microstructured symbol area;
a circuit board on which the at least one light source of the planar light guides is arranged and fixed;
a panel fixed to the light guide stack by at least one of: a substance-to-substance connection, a non-positive connection, and a positive connection, to which the circuit board is fixed while resting against a mounting surface, wherein the panel has several light shafts that are open on both sides and respectively accommodate the at least one of the light sources of the circuit board, so that the at least one light source is situated opposite the associated end face in order to couple the light into the associated end face, wherein a first clearance, which is present in the stacking direction, between two light shafts spaced apart transversely to the stacking direction and the associated light source accommodated in the respective light shaft is smaller than each second clearance, which is present in the stacking direction, between the remaining light shafts and the associated light source accommodated in the respective light shaft.