Optically functional multilayer structure and related method of manufacture

Patent metadata

Field	Value
Publication number	US-12159965-B2
Application number	US-202318476676-A
Country	US
Kind code	B2
Filing date	Sep 28, 2023
Priority date	Jul 2, 2022
Publication date	Dec 3, 2024
Grant date	Dec 3, 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 preferably additively printed on the substrate film; a light source provided upon a first side of the substrate film to internally illuminate at least portion of the structure for external perception; 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; and a reflector design comprising at least one material layer, said reflector design being configured to reflect, the light emitted by the light source and incident upon the reflector design.

First claim

The invention claimed is:

1. An integrated optically functional multilayer structure, comprising:
a flexible, optionally 3D-formable and thermoplastic, substrate film arranged with a circuit design comprising at least a number of electrical conductors additively printed on the substrate film;
a light source provided upon a first side of the substrate film to internally illuminate at least portion of the structure for external perception;
an optically transmissive plastic layer, optionally of thermoplastic material, produced upon the first side of the substrate film, said plastic layer at least laterally surrounding, optionally also at least partially covering, the light source, the substrate film optionally comprising material or material layer same as that of the plastic layer or at least having a similar or lower refractive index therewith;
a circuit board hosting the light source and provided on the substrate film; and
a reflector design comprising at least one material layer, said reflector design being configured to reflect, optionally dominantly specularly, the light emitted by the light source and incident upon the reflector design optionally towards the plastic layer, wherein the reflector design at least locally defines a collimating reflector surface,
wherein said circuit board comprises a number of holes for enabling light transmission therethrough, or wherein the light source is off-centered in relation to the axis of symmetry of the collimating reflector surface and wherein the collimating reflector surface resides on a side of the layer opposite to a side facing the first side of the substrate film hosting the light source.

2. The structure of claim 1 , wherein the reflectance of the reflector design is at least locally about 75%, optionally essentially all visible, wavelengths of light.

3. The structure of claim 1 , wherein the reflector design essentially at least locally defines a parabolic reflector surface.

4. The structure of claim 1 , wherein the reflector design resides on a side of the plastic layer opposite to a side facing the first side of the substrate film hosting the light source.

5. The structure of claim 1 , wherein the reflector design is configured on or in the plastic layer to reflect and steer light emitted by the light source and incident on the reflector design to propagate towards an outcoupling area and optionally more towards related surface normal of the plastic layer for outcoupling the light at least from the plastic layer or the overall structure.

6. The structure of claim 1 , wherein the reflector design at least locally comprises at least one element selected from the group consisting of:
electrically conductive material;
metal, optionally metal particles, further optionally provided upon or within the substrate film or further film or a further film or layer included in the structure;
a plurality of stacked, superimposed material layers of at least two mutually different refractive indexes, optionally defining a Bragg mirror;
thin-film coating, optionally PVD (physical vapor deposition) coating; and
ink or paint.

7. The structure of claim 1 , wherein the light source comprises a semiconductor, a packaged semiconductor, a chip-on-board semiconductor, bare chip, electroluminescent or a printed LED, optionally a multi-color such as RGB (red-green-blue) LED.

8. A method for manufacturing an integrated optically functional multilayer structure, the method comprising:
obtaining a flexible, optionally 3D-formable and thermoplastic, substrate film, optionally a multilayer film, provided with a circuit design comprising at least a number of electrical conductors additively printed on the substrate film;
arranging at least one light source upon a first side of the substrate film;
producing, optionally through molding or 3D printing, an optically transmissive plastic layer upon the first side of the substrate film, said plastic layer at least laterally surrounding or neighboring, optionally also at least partially covering, the light source;
providing, optionally including printing, coating, laminating or molding, a reflector design comprising at least one material layer, optionally comprising a stack of material layers and/or a layer of electrically conductive and/or metallic material, configured to reflect, optionally dominantly specularly, the light emitted by the at least one light source and incident upon the reflector design, optionally towards the plastic layer, wherein the reflector design at least locally defines a collimating reflector surface; and
providing the reflector design during molding and/or printing by utilizing a suitable mold shape or afterwards by a selected subtractive or additive processing.

9. A method for manufacturing an integrated optically functional multilayer structure, the method comprising:
obtaining a flexible, optionally 3D-formable and thermoplastic, substrate film, optionally a multilayer film, provided with a circuit design comprising at least a number of electrical conductors additively printed on the substrate film;
arranging at least one light source upon a first side of the substrate film;
producing, optionally through molding or 3D printing, an optically transmissive plastic layer upon the first side of the substrate film, said plastic layer at least laterally surrounding or neighboring, optionally also at least partially covering, the light source;
providing, optionally including printing, coating, laminating or molding, a reflector design comprising at least one material layer, optionally comprising a stack of material layers and/or a layer of electrically conductive and/or metallic material, configured to reflect, optionally dominantly specularly, the light emitted by the at least one light source and incident upon the reflector design, optionally towards the plastic layer, wherein the reflector design at least locally defines a collimating reflector surface; and
the method 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, optionally LED, 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.

10. A method for manufacturing an integrated optically functional multilayer structure, the method comprising:
obtaining a flexible, optionally 3D-formable and thermoplastic, substrate film, optionally a multilayer film, provided with a circuit design comprising at least a number of electrical conductors additively printed on the substrate film;
arranging at least one light source upon a first side of the substrate film;
producing, optionally through molding or 3D printing, an optically transmissive plastic layer upon the first side of the substrate film, said plastic layer at least laterally surrounding or neighboring, optionally also at least partially covering, the light source;
providing, optionally including printing, coating, laminating or molding, a reflector design comprising at least

Assignees

• Tactotek Oy

Inventors

• Keränen Antti
• Torvinen Sami
• 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

• H10W90/00 Primary

  Package configurations · CPC title

• H10H20/0364

  of interconnections · CPC title

• H10H20/0363

  of optical field-shaping means · CPC title

• H10H20/857

  Interconnections, e.g. lead-frames, bond wires or solder balls · CPC title

• H10H20/01

  Manufacture or treatment · CPC title