Optically functionally multilayer structure suitable for large area illumination and related method of manufacture

Patent metadata

Field	Value
Publication number	US-11906774-B2
Application number	US-202318326110-A
Country	US
Kind code	B2
Filing date	May 31, 2023
Priority date	Jul 2, 2022
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

An integrated optically functional multilayer structure includes a flexible, substrate film arranged with a circuit design including at least a number of electrical conductors on the substrate film; and a plurality of top-emitting, bottom-installed light sources provided upon a first side of the substrate film to internally illuminate at least portion of the structure for external perception via associated outcoupling areas, wherein for each light source of the plurality of light sources there is optically transmissive plastic layer, produced upon the first side of the substrate film, said plastic layer at least laterally surrounding the light source, the substrate film at least having a similar or lower refractive index therewith; and reflector design including at least one material layer, provided at least upon the light source and configured to reflect the light emitted by the light source and incident upon the reflective layer towards the plastic layer.

First claim

The invention claimed is:

1. A method for manufacturing an integrated optically functional multilayer structure, comprising:
obtaining a flexible substrate film provided with a circuit design comprising at least a number of electrical conductors additively produced on the substrate film;
arranging a plurality of top-emitting, bottom-installed light sources provided upon a first side of the substrate film;
producing for each light source of the plurality of light sources, optically transmissive plastic layer upon the first side of the substrate film, said plastic layer at least laterally surrounding or neighbouring the light source, wherein producing the plastic layer comprises providing a masterbatch comprising selective wavelength resin in a selected let-down ratio;
providing a reflector design comprising at least one material layer configured to reflect, the light emitted by the plurality of light sources and incident upon the reflector design; and
providing at least one further material layer having a lower refractive index than the plastic layer so that said at least one further material layer and said plastic layer are optically connected so as to redirect at least part of the light emitted by at least one of the plurality of light sources, propagated within the plastic layer and incident upon the at least one further material layer back into the plastic layer by total internal reflection.

2. A method for manufacturing an integrated optically functional multilayer structure, comprising:
obtaining a flexible substrate film provided with a circuit design comprising at least a number of electrical conductors additively produced on the substrate film;
arranging a plurality of top-emitting, bottom-installed light sources provided upon a first side of the substrate film;
producing for each light source of the plurality of light sources, optically transmissive plastic layer upon the first side of the substrate film, said plastic layer at least laterally surrounding or neighboring the light source, wherein producing the plastic layer comprises providing a masterbatch comprising selective wavelength resin in a selected let-down ratio of about 5% or less; and
providing a reflector design comprising at least one material layer configured to reflect, the light emitted by the plurality of light sources and incident upon the reflector design.

3. The method of claim 2 , wherein the masterbatch is added in an injection mold base resin constituting the plastic layer.

4. The method of claim 2 , further comprising at least one step selected from the group consisting of:
laminating two or more layers included in the multilayer structure together by pressure-sensitive adhesive, optically clear adhesive, solvent, ink, heat, pressure, or hot melt;
additively producing such as printing or 3D-printing at least one layer such as the plastic layer, a layer of the at least one reflective layer, a further material layer, a lightguide, a light outcoupling element, a diffuser, and/or other optically functional element; and
providing a top-emitting light source of the plurality of light sources on its side on the substrate film so that its contact pads face a direction transverse to the surface of the substrate film and are contacted by conductive adhesive provided on the substrate film electrically joining the contact pads with the circuit design, the conductive adhesive being at least partially surrounded on the substrate film by structural adhesive provided on the substrate film.

5. The method of claim 2 , comprising interconnecting a plurality of modules together, wherein each module comprises
at least one of
one or more light sources of the plurality of light sources;
at least a portion of the substrate film; and
the circuit design;

or
at least a portion of a layer of the reflector design and/or at least a portion of the plastic layer.

6. An integrated optically functional multilayer structure suitable for large area dynamic illumination, comprising:
a flexible substrate film arranged with a circuit design comprising at least a number of electrical conductors printed on the substrate film; and
a plurality of top-emitting, bottom-installed light sources provided upon a first side of the substrate film to internally illuminate at least portion of the structure for external perception via associated outcoupling areas,
wherein for each light source of the plurality of light sources there is an optically transmissive plastic layer produced upon the first side of the substrate film, said plastic layer at least laterally surrounding the light source, the substrate film at least having a similar or lower refractive index therewith, wherein the plastic layer comprises tinted resin; and
a reflector design comprising at least one material layer, provided at least upon the light source and configured to reflect the light emitted by the light source and incident upon the reflective layer towards the plastic layer.

7. The structure of claim 6 , wherein the reflectance of the reflector design is at least locally about 75% wavelengths of light.

8. The structure of claim 6 , wherein the tinted resin comprises infrared resin.

9. The structure of claim 6 , wherein the reflector design is configured on a direct optical emission path from at least one light source of the plurality of light sources so as to reflect light incoupled into the plastic layer from the light source and incident on the reflector design to align more with a lateral plane of the plastic layer substantially transverse to a surface normal of the plastic layer.

10. The structure of claim 6 , wherein the reflector design is configured on or in the plastic layer to reflect and steer light emitted by at least one light source of the plurality of light sources and incident on the reflector design to propagate towards an outcoupling area for outcoupling the light at least from the plastic layer or the overall structure.

11. The structure of claim 6 , wherein the reflector design at least locally comprises a material stack of a plurality of superimposed material layers having at least two mutually different refractive indexes.

12. The structure of claim 6 , wherein the reflector design comprises at least one element selected from the group consisting of:
electrically conductive material;
metal;
thin-film coating; and
ink or paint.

13. The structure of claim 6 , wherein one or more portions of the reflector design are located on a side of the plastic layer equal, opposite, and/or transverse to a side facing the first side of the substrate film hosting at least one light source of the plurality of light sources.

14. The structure of claim 6 , further comprising at least one further material layer in contact with the reflector design, said at least one further material layer having a lower refractive index than the plastic layer, said at least one further material layer and said plastic layer being optically connected so as to redirect at least part of the light emitted by at least one light source of the plurality of light sources, propagated within the plastic layer and incident upon the at least one further material layer back into the plastic layer by total internal reflection.

15. The structure of claim 14 , wherein a layer of the reflector design, a layer of the at least one further material layer, and the plastic layer are at least locally superimposed in terms of their materials so that the material of the layer of the at least one further material layer is stacked between the materials of the layer of the reflector design and the plastic layer.

Assignees

• Tactotek Oy

Inventors

• Keränen Antti
• Heikkinen Tero
• Korhonen Pasi
• Apilo Pälvi
• Heikkinen Mikko
• Sääski Jarmo
• Niskala Paavo
• Wallenius Ville
• Tuovinen Heikki
• Asikkala Janne
• Salmi Taneli
• Kela Suvi
• Rusanen Outi
• Juvani Johanna
• Sippari Mikko
• Simula Tomi
• Rautio Tapio
• Yrjänä Samuli
• Rajaniemi Tero
• Koivikko Simo
• Hintikka Juha-Matti
• Sinivaara Hasse
• Bräysy Vinski
• Migliore Olimpia
• Sepponen Juha

Classifications

• G02B6/0031 Primary

  Reflecting element, sheet or layer · CPC title

• G02B6/004

  Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles · CPC title

• G02B6/0021 Primary

  for housing at least a part of the light source, e.g. by forming holes or recesses · CPC title

• G02B6/0036

  2-D arrangement of prisms, protrusions, indentations or roughened surfaces · CPC title

• G02B6/0041

  provided in the bulk of the light guide · CPC title