Optical incoupling elements, related methods and uses

Abstract

To improve the light incoupling efficiency and light distribution control for light guides. [Solution] The optical incoupling element 100 comprises a substrate 100A and a three-dimensionally formed optical surface composed of a periodic pattern feature portion including an optical functional cavity formed in the substrate. The optical surface incouples incident light and adjusts the direction of light transmitted through the interface between the substrate 100A and the light guide medium, thereby forming an optical path that propagates within the light guide medium by internal total internal reflection. The element 100 is configured to receive light from a direction parallel to the plane of the light guide medium and to be attachable to at least one plane of the light guide medium.

Description

[Technical Field]

[0001] The present invention generally relates to providing optical structures for waveguides and methods for manufacturing them. In particular, the present invention relates to device solutions, related methods and uses, based on an integrated cavity optical system having a predetermined shape, configured to incouple outgoing light into an optical waveguide and to control the distribution of light propagation through the waveguide. [Background technology]

[0002] Optical waveguide or light guide technology is widely used in a variety of cutting-edge applications. The appropriate selection of the light distribution system often determines the illumination performance of optical waveguides in lighting and display applications. A typical light guide (LG) system includes components for edge-incoupling light rays emitted from one or more emitters, components for distributing light through light guide elements, and components or regions for light extraction (outcoupling). The incoupling structure receives light and adjusts its direction to guide the light rays into the distribution region. Advanced light guides feature optical patterns that control the optical edge-incoupling efficiency of light upon incidence into the light guide.

[0003] Conventional light guide solutions designed for illumination applications still utilize a number of separate optical films, such as brightness enhancement films (BEFs), to control the angular distribution of emitted light and achieve desired optical performance. Known light guide solutions implemented without BEFs typically employ microlenses and V-groove-shaped optical patterns. It is impossible to achieve the desired, perfectly controlled light distribution using such solutions. Optical incoupling is typically performed at the edge of the light guide without advanced optical solutions. In some special cases, such as in augmented reality and virtual reality headsets, planar incoupling is used based on surface relief gratings incorporated into the light guide element.

[0004] US 2018 / 031840 A1 (Hofmann et al.) discloses an optical element with an embedded optical grating for extracting light from a light guide. The surface of the grating is coated with an optically effective layer using known methods such as chemical vapor deposition (CVD) or physical vapor deposition (PVD). Furthermore, recesses present in the grating are filled with optical cement or optical adhesive material.

[0005] US 10,598,938 B1 (Huang and Lee) discloses an angle-selective oblique grating coupler for controlling the angle at which light is outcoupled from or incoupled to a light guide. Selectivity can be achieved by modulating the refractive index between gratings or by modulating the duty cycle of the gratings in different regions.

[0006] Kress[1] discloses in-couplers and out-couplers for optical waveguides, the couplers comprising different types of gratings configured for transmission and / or reflection functions. The couplers are sandwiched / embedded in a light guide or provided as a surface relief solution.

[0007] Moon et al. [2] disclose an outcoupler that uses a microstructured hollow (air) cavity grating to improve light extraction from an LED device. The hollow cavity is fabricated in a semiconductor material in a typical manner. Apart from LEDs, no other applications of the outcoupler solution have been provided (e.g., in light guides).

[0008] Angulo Barrios and Canalejas-Tejero[3] This paper discloses an optical coupling solution in a flexible Scotch tape waveguide obtained via an integrated metal diffraction grating. An incoupling grating and an outcoupling grating are embedded inside the two layers of the Scotch tape, allowing the Scotch tape to function as an optical waveguide. The gratings are implemented as a metal (Al) nanohole array (NHA) grating.

[0009] US 2015 / 192742 A1 (Tarsa and Durkee) discloses a light extraction film laminated to the surface of a light guide. The light extraction function is based on TIR (Total Internal Reflection). When the extraction film is fixed to the light guide by lamination or other means, an air pocket is formed between the film and the light guide.

[0010] The design and optimization of light guide-based lighting solutions face several challenges, including non-uniform light distribution within the light guide, insufficient outcoupling, light trapping, and / or extraction efficiency. Furthermore, the aforementioned solutions have limitations in that they cannot provide integrated air cavity optics-based solutions with satisfactory versatility and adaptability for a variety of target applications, such as large window lighting with planar light incoupling.

[0011] In this regard, improvements in the field of optical structures for non-fiber optic light guides (aimed at increasing brightness uniformity and improving the optical efficiency of the light guides) remain desirable, in order to address the challenges associated with the manufacturing and assembly of current existing solutions. [Overview of the project]

[0012] The object of the present invention is to at least mitigate the problems arising from the limitations and drawbacks of related technologies. This object is achieved by various embodiments of the optical incoupling element according to the definition of independent claim 1.

[0013] In one embodiment, an optical incoupling element for a light guide is provided in the form of a discrete optical functional item. The discrete optical functional item comprises a substrate and at least one three-dimensionally formed optical surface, the at least one three-dimensionally formed optical surface configured to incouple all incident light and to adjust the direction of the incoupling light transmitted through an optical contact surface established at the interface between the element substrate and the light guide medium, thereby causing the incoupling light to obtain a propagation path through the light guide medium via a series of internal total internal reflections. The element is configured to receive light on the at least one three-dimensionally formed optical surface from a direction substantially parallel to the longitudinal plane of the planar light guide, thereby causing substantially all light emitted by the emitter device to be incident on the optical incoupling element and substantially all light received by the incoupling element to be incoupled to the light guide. The element is further configured to be attachable to at least one plane of the light guide.

[0014] In this embodiment, the light emitted from the emitter device is incident on the optical incoupling element but not on the edge of the light guide. Therefore, all light received in the incoupling element is incoupled from its plane into the light guide.

[0015] In this embodiment, the incoupling light is redirected at the interface between the three-dimensionally formed optical surface and the surroundings and / or at the interface between the element substrate and the light guide medium to obtain the propagation path through the light guide, and the optical incoupling element is configured such that the angle of incidence at the interface between the light guide medium and the surroundings is greater than or equal to the critical angle of internal total internal reflection.

[0016] In an embodiment, the in-coupling element includes at least one optical pattern formed by a number of periodic pattern features formed in an element substrate and configured as an optical functional cavity.

[0017] In an embodiment, the in-coupling element is an optical functional cavity completely embedded in the element substrate, and includes at least one optical pattern formed by an optical functional cavity filled with a material having a refractive index different from that of the material of the substrate surrounding the cavity.

[0018] In an embodiment, the at least one optical pattern is configured to in-couple incident light and convert the direction of the in-coupled light at an interface between each of the cavities and the material of the substrate surrounding the cavity, whereby the in-coupled light obtains the propagation path through the light guide medium, and the incident angle at the interface between the light guide medium and the surroundings, and optionally, the incident angle at the interface between each cavity and the material of the substrate surrounding the cavity, are greater than or equal to the critical angle of total internal reflection.

[0019] In an embodiment, the at least one three-dimensionally formed optical surface and optionally the at least one cavity pattern in the in-coupling element are configured to perform an optical function related to in-coupling and adjusting the direction of received light, and the optical function is selected from the group consisting of a reflection function, an absorption function, a transmission function, a collimation function, a refraction function, a diffraction function, a polarization function, and any combination thereof.

[0020] In an embodiment, each individual cavity in the pattern has a number of optical functional surfaces. In an embodiment, the optical functional surface(s) is established by any surface(s) formed at an interface between each cavity and the material of the substrate surrounding the cavity.

[0021] In an embodiment, the three-dimensionally formed optical surface and / or the optical functional surface(s) formed in the cavity pattern in the incoupling element is established by any one of a low refractive index reflector, a polarizer, a diffuser, an absorber, or any combination thereof.

[0022] In an embodiment, the cavity pattern(s) in the incoupling element is configured to perform at least one optical function by adjusting a number of parameters related to the cavity or cavity group in the pattern, and the number of parameters includes individual parameters or any combination of parameters selected from the group consisting of dimensions, shape, cross-sectional profile, orientation, periodicity, and fill factor.

[0023] In different embodiments, the cavity in the incoupling element is configured and arranged within the cavity pattern to form a substantially variable periodic pattern or a substantially constant periodic pattern.

[0024] In an embodiment, in the cavity pattern, the cavity is established by discrete or at least partially continuous pattern features.

[0025] In an embodiment, the cavity is established by a two-dimensional or three-dimensional pattern feature having a cross-sectional profile selected from the group consisting of linear, rectangular, triangular, blazed, inclined, trapezoidal, curved, wavy, and sinusoidal profiles.

[0026] In one embodiment, the optical incoupling element comprises at least two substrate components and optionally a layer, wherein at least one cavity pattern is formed on any substantially flat plane of the substrate components, thereby establishing a substrate component having a patterned surface that abuts against the overall flat plane of another substrate component, and thereby forming at least one embedded cavity pattern having embedded cavities alternating with flat bonding regions at the interface between the patterned substrate surface of the substrate components and the overall flat plane.

[0027] In the incoupling element, the element substrate or the substrate component having at least a patterned surface may be formed of a substantially optically transparent material. In the incoupling element, the substrate component having an overall flat and planar substrate surface may further be formed of any one of optically transparent materials, colored materials, reflective materials, and combinations thereof.

[0028] In one embodiment, the embedded cavity is filled with a gaseous material such as air.

[0029] In one embodiment, the incoupling element is composed of a number of embedded cavity patterns arranged in a stacked configuration.

[0030] In this embodiment, the incoupling element is provided with a light guide mounting surface, and the light guide mounting surface is an adhesive layer.

[0031] In one embodiment, the incoupling element is configured such that at least a portion of its outer surface, located substantially opposite the light guide mounting surface, is tapered with respect to the longitudinal plane of the planar light guide.

[0032] In the embodiment, the three-dimensionally formed optical surface of the incoupling element, which optionally has at least one embedding pattern, is positioned on a plane defined by a surface of the element located substantially opposite to the light guide mounting surface.

[0033] In the embodiment, the three-dimensionally formed optical surface of the incoupling element, which optionally has at least one embedding pattern, is positioned on a plane defined by a surface of the element that is substantially perpendicular to the longitudinal plane of the planar light guide and faces the emitter device.

[0034] In one embodiment, the incoupling element comprises at least two adjacent functional zones independently configured to perform optical functions related to incoupling incident light and adjusting the direction of the incoupling light so that the incoupling light is directed (or redirected) toward the light guide medium.

[0035] In this embodiment, the at least two adjacent functional zones are optionally connected to the interface layer. It is formed by separate element modules interconnected with adhesive.

[0036] In one embodiment, the incoupling element is provided in the form of an elongated strip.

[0037] In another aspect, an arrangement is provided comprising at least two incoupling elements arranged on the light guide according to the definition of independent claim 29. In the arrangement, each of the elements is an optical incoupling element according to the aspect.

[0038] In another aspect, a method is provided for manufacturing an optical incoupling element, which is in the form of a discrete optical functional item, according to the definition of independent claim 30.

[0039] In the embodiment, - To manufacture a master tool for the pattern by a manufacturing method selected from lithography, 3D printing, micromachining, laser engraving, or any combination thereof, -Transferring the pattern onto the element substrate to generate the optical surface having a predetermined optical function, Includes, The at least one pattern is configured to incouple incident light and adjust the direction of the incoupled light transmitted through an optical contact surface established at the interface between the element substrate and the light guide medium, thereby causing the incoupled light to obtain a propagation path through the light guide medium via a series of internal total internal reflections, and the element is configured to receive light on the at least one pattern from a direction substantially parallel to the longitudinal plane of the planar light guide.

[0040] In embodiments, the method includes generating one or more embedded cavity patterns by applying an additional substrate layer to the surface of a patterned element by a lamination method selected from roll-to-roll lamination, roll-to-sheet lamination, or sheet-to-sheet lamination.

[0041] In embodiments, the method further includes duplication of the fabricated pattern, the pattern duplication method being selected from imprint, extrusion, or 3D printing.

[0042] In another aspect, a light guide is provided according to the definition of independent claim 33. The light guide comprises an optically transparent medium configured to establish a path for light propagation through the light guide, and at least one optical incoupling element by any of the surfaces, which is optionally provided as part of an arrangement by any other surface, wherein the optical incoupling element(s) are attachable to at least one plane of the light guide.

[0043] In this embodiment, the optical incoupling element(s) is attached to the surface of the light guide by adhesive.

[0044] In another aspect, according to the definition of independent claim 35, the use of a light guide in any of the aforementioned aspects is provided in illumination and / or display.

[0045] In a further aspect, an optical unit is provided according to the definition of independent claim 36. The optical unit comprises at least one optical incoupling element having an adhesive layer for attaching a light guide, and at least one emitter It is equipped with a device.

[0046] In this embodiment, the at least one emitter device is at least partially integrated into the substrate material forming the optical incoupling element.

[0047] In the embodiment, the at least one emitter device is selected from the group consisting of light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), laser diodes, LED bars, OLED strips, microchip LED strips, and cold cathode tubes.

[0048] In one embodiment, the optical unit comprises at least one optical emitter device configured to emit monochromatic light, and the optical incoupling element including the wavelength conversion layer.

[0049] The usefulness of the present invention arises for various reasons, depending on each specific embodiment. First, the present invention relates to a novel optical incoupling structure configured to incouple photons of optical radiation (light) emitted from at least one light source, and to adjust the direction of the incoupling rays and mediate light propagation through a light guide medium. The incoupling element according to the present invention is advantageous to be designed for planar, non-fiber type light guides.

[0050] One of the main advantages provided by the optical incoupling element according to the present invention is the incoupling of light to a planar light guide surface(s). Thus, the element incouples light rays arriving at the planar light guide surface from any direction, enabling efficient capture of the light rays within the planar light guide. At the same time, the incoupling element adjusts the direction of the incoupled light so that the light rays remain inside the light guide (preventing light leakage). In particular, the element of this disclosure enables the incoupling of light to large (planar) window panes, which was not possible with conventional solutions for incoupling light from the edge of a window.

[0051] Known incoupling solutions are typically fixed solid structures located inside light guides, which, for the reasons mentioned above, prevent their efficient use on pre-installed window surfaces. From a manufacturing standpoint, such fixed incoupling structures are not suitable for mass production, such as by etching them into window glass installed in buildings. Furthermore, the aforementioned fixed solutions do not allow for the combination of different optical functionalities within the same incoupling structure.

[0052] The incoupling elements presented herein offer greater flexibility in positioning the light source. The optical emitter can be integrated into the element, or mounted on or adjacent to the element. Alternatively, the emitter can be positioned at a distance from the element to avoid the element and light guide receiving thermal energy (for example, in the case of a laser light source).

[0053] The incoupling element can be assembled, for example, to the top and / or bottom surface of a planar light guide by an optically transparent adhesive to form a sealed optical contact. Incident light incoupled to the element pattern(s) is deflected by a certain angle from its original propagation path by an (air) cavity optical system embedded inside the incoupling element. The fully integrated, embedded cavity optical system is based on a two-dimensional or three-dimensional pattern matrix to achieve desired light control by profile configuration, and the three-dimensional pattern matrix can consist of a single profile or multiple profiles.

[0054] One of the primary optical functions of the incoupling element according to this disclosure is to regulate the incoupling and direction of light incident on an optical pattern at an incident angle greater than the critical angle for internal total internal reflection. This feature can be achieved by providing the incoupling element with various embedded features designed to perform a predetermined optical function (one or more), such as reflection, refraction, deflection, diffraction, diffusion, and any combination thereof. These optical functions, as well as other optical functions such as light transmission, absorption, and polarization, are achieved by carefully selecting the material of the element substrate component and / or layer, pattern profile and filler material, fill factor, surface coating, adhesive material, etc.

[0055] One of the key features of an incoupling element is its integration of a light source, which allows for easier and more reliable assembly and use. This means providing a so-called "all-in-one" solution, i.e., a one-part element that can be directly bonded to a planar light guide surface, for example, by adhesive.

[0056] Incoupling elements can employ a variety of configurations. In some cases, the incoupling element is formed from discrete three-dimensional optical components of a predetermined shape that can be attached to the surface of a planar waveguide. This element can be provided as an elongated band or strip, or as a substantially circular dot-shaped component. Furthermore, the incoupling element can utilize a light source that emits light in one direction, two directions, or multiple directions (360° emission and propagation).

[0057] Incoupling elements are extremely easy to install and offer flexibility for removal, modification, and reinstallation to desired locations. The optical structure(s) within the element are protected from external conditions and are therefore highly reliable. Furthermore, the characteristics of the outcoupling light are also improved through enhanced incoupling efficiency and improved light distribution control.

[0058] The optical incoupling elements described herein are easy to use and highly reliable due to their embedded cavity optics. The embedded cavity optics, due to their internal properties, are not damaged or malfunctioned by normal handling procedures, including assembly and cleaning. In a ready-to-use state, the element has no surface relief pattern formed on its surface. In certain configurations, the element includes a light source fully integrated within the substrate material in which the element is constructed. This makes the incoupling element highly durable and reliable, and easy to install. Furthermore, the element with the light source integrated can optionally be housed in a protective enclosure.

[0059] Depending on the integrated light source characteristics, additional illumination functions can be employed, such as those related to monochromatic or multichromatic illumination. Furthermore, special optical emission ranges, such as IR and / or UV radiation, can be utilized for additional purposes, such as UV-C radiation for sterilization and disinfection methods.

[0060] One of the primary objectives of the optical incoupling element according to the present invention is to improve the optical performance and efficiency of a light guide and enhance the light distribution through it. The incoupling element enables integrated control of the distribution of light propagation along the horizontal and vertical axes in the light guide medium. The incoupling element can be used alone or in combination with an optically harmonic tape. Placing the incoupling tape and the optical deflection tape on the same light guide element is beneficial for optimizing optical performance.

[0061] The incoupling element improves the optical performance of the light guide while providing remarkable mechanical reliability and excellent environmental durability.

[0062] The terms “optical radiation” and “light” are used mostly as synonyms unless explicitly stated otherwise, and refer to electromagnetic radiation within specific parts of the electromagnetic spectrum, which covers ultraviolet (UV) radiation, visible light, and infrared (IR) radiation. In some cases, visible light is preferred.

[0063] In its broadest sense, in this disclosure, the terms “light guide,” “waveguide,” or “optical waveguide” refer to a device or structure configured to transmit light along it (for example, from a light source to a light extraction surface). This definition includes any type of light guide, including but not limited to light pipe components, light guide plates, light guide panels, etc.

[0064] The expression "a number of" in this specification refers to any positive number starting from 1. This refers to an integer, such as 1, 2, or 3. On the other hand, the expression "a plurality of" in this specification refers to any positive integer starting from 2, such as 2, 3, or 4.

[0065] The terms “first” and “second” are not intended to indicate any order, quantity, or importance, but rather are simply used to distinguish one element from another. [Brief explanation of the drawing]

[0066] Different embodiments of the present invention will become apparent by considering the detailed description and the accompanying drawings, as shown in the drawings.

[0067] Figures 1A to 1I are cross-sectional views of a light guide to which optical incoupling elements 100 and related devices (units) 250 according to various embodiments are attached. Figure 2A is a cross-sectional view of the multi-phase incoupling element 100 according to this embodiment. Figure 2B is a cross-sectional view showing an arrangement comprising two incoupling elements 100. Figure 3 is a diagram (cross-sectional view) showing various configurations for using the incoupling element 100 on a light guide. Figures 4 and 5 show an incoupling element 100 having an integrated cavity optical system adapted for collimation, according to an embodiment. Figure 6 shows an optical incoupling solution comprising an incoupling element 100 and an optical tape 10. Figure 7 shows a ray tracing model of light incoupling by an incoupling element 100 optically connected to the plane of the light guide. Figure 8A shows various configurations of a light guide comprising an incoupling element 100 and an optical tape 10. Figures 8B and 8C are comparative graphs illustrating the distribution of incoupling light in a planar light guide when only an incoupling element is provided (Figure 8B) and when both an incoupling element and the optical tape 10 are used (Figure 8C). Figure 9 is a comparative graph illustrating the vertical distribution (A) and horizontal distribution (B) of incoupling light in a planar light guide equipped with an incoupling element according to an embodiment. Figures 10A and 10B are illustrative comparative graphs illustrating the distribution of incoupling light in a planar light guide equipped with an incoupling element configured as a tapered element without a collimation optical system in combination with an optical tape 10 (Figure 10A), and in a planar light guide equipped with an incoupling element configured as a tapered element with a collimation optical system in combination with an optical tape 10 (Figure 10B). be. Figure 11 shows different light guide configurations (top view) in which an optical incoupling element 100 or an optical incoupling unit 250 is assembled on the surface of the light guide. [Modes for carrying out the invention]

[0068] Detailed embodiments of the present invention are disclosed herein with reference to the accompanying drawings. The same reference numerals are used throughout the drawings to refer to the same components. The following quote is used for the component.

[0069] 100, 100-1, 100-2 - Optical incoupling elements 100A - Element Substrate 100P1, 100P2 - Element Module, Multi-Phase Optical Incoupling Element Component 101 - Optical Pattern 102 - Optical (pattern) feature area / cavity having optical functional surfaces 1021, 1022, 1023 103 - Contact area within the element 104, 105 - Optical surfaces formed in three dimensions. 104 is the uppermost surface of the incoupling element, which has an optionally shaped region, and 105 is the side end surface of the incoupling element facing the emitter device. 106 - Additional Wedge Profiles 107 - Contact surface between the element and the light guide In element 100: 1011 - Optical Functional Element Structure 1011A, 1011B - Substrate component and additional substrate component (layer) having a patterned surface, respectively. 1012 - Additional functional layer (adhesive) 1013 - Additional functional layer (outer coating) 1015 - Internal functional components (layers) 10. Optical tape (control over the distribution of light propagation through the light guide) On tape 10: 11-Pattern 12. Optical (pattern) feature area / cavity having optical functional surfaces 121, 122 13-Contact Area 111-Optical functional layer 111A and 111B - Patterned substrate layer and additional substrate layer, respectively. 112, 113 - Additional functional layers for Tape 10 20-Optical waveguide (medium) 21-Outcoupling Pattern 30. Emitter device (light source) 31. Emitted optical radiation 32-Incoupled and / or redirected optical radiation 33. Extracted electromagnetic optical rays 250 - Optical device (unit)

[0070] Figures 1A to 1I show various embodiments of optical incoupling elements for optical waveguides in 100. Several basic configurations are shown in Figures 1A and 1B.

[0071] Figures 1A and 1B are cross-sectional views of the optical waveguide structure 20, in which an optical incoupling element 100 (hereinafter referred to as "incoupling element") is attached to at least one surface of the waveguide. The attached state is shown. An optical waveguide, also called a light guide, is a structure configured to direct optical radiation (light) emitted by at least one suitable emitter device 30 towards a specific area where illumination is needed. A light guide is a planar (non-fiber) light guide having substantially planar (or more) surfaces. In a basic light guide layout (for example, shown in either Figure 1A or 1B), the top surface, bottom surface, and two or more lateral (side) surfaces or edges can be distinguished. The top and bottom surfaces form the horizontal plane of the light guide, while the edges extend substantially vertically between the top and bottom surfaces, with an optional but predetermined angle of inclination, along the path surrounding the waveguide element when viewed as a two-dimensional shape (i.e., the periphery). The longitudinal plane of the planar light guide lies along its horizontal plane(s).

[0072] The light guide comprises a translucent carrier medium formed from an optical polymer or glass. In an exemplary embodiment, the light guide (carrier) medium is polymethyl methacrylate (PMMA). For clarity, reference numeral 20 is used to indicate both the light guide as an entity and the carrier medium on which the light guide is made.

[0073] In some embodiments, the incoupling element 100 is provided as a discrete three-dimensional object having a predetermined shape. Here, the expression “three-dimensional” is used to indicate that the element 100 is three-dimensional rather than flat, as it can be measured in three different dimensions (length, width, and height / thickness).

[0074] The element 100 can be installed on one side or both sides (top, bottom) of a planar light guide. For example, it is reasonable to install the element 100 on the same side of a light guide that supports other optical structures such as an optical outcoupling / extraction layer. In particular, in window lighting, due to environmental factors, it is beneficial to assemble all optical structures on the window surface facing the interior of a building or the space between stacked windows.

[0075] When the incoupling element is installed in the light guide, an optical contact is established at the interface between the light guide medium 20 and the element medium (substrate) 100A. The optical contact may be established via a mechanical connection or, for example, via bonding with an optically transparent adhesive. The surface of the element 100 that forms the optical contact is indicated by reference numeral 107 in Figure 1A.

[0076] The element 100 comprises an upper surface and a lower surface that are opposite to each other. In some configurations, the upper and lower surfaces are parallel to each other and parallel to the longitudinal (horizontal) plane of the planar light guide (see Figures 1C and 1D). In some configurations, the incoupling element may include at least one surface, or at least a portion of such at least one surface, that forms a shaping region.

[0077] In some configurations, as shown in Figures 1A and 1B, the shaping region is formed on the uppermost surface 104 of the element 100. Thus, the shaping region is defined by at least a portion of the uppermost surface 104 located substantially opposite the light guide mounting surface. Due to this shaping region (e.g., surface 104), the element may be tapered. A tapered shape means that the size / thickness gradually increases or decreases toward one end of the element. In practice, the taper is typically constructed such that the thickness of the element decreases toward the end of the element 100 opposite the side end 105 (Figure 1B) facing the emitter device.

[0078] Therefore, the tapered incoupling element 100 has at least one surface that is inclined (sloping without a curve) or curved (e.g., convex or concave) with respect to the longitudinal plane of the planar light guide, or such at least one surface It is possible to have a part of it.

[0079] An optical surface formed in three dimensions, such as the uppermost surface 104, can be called an optical wedge. An element 100 having such an optical wedge 104 can be configured, for example, for hybrid coupling.

[0080] The emitter device(s) 30 are positioned substantially laterally to one of the sides of the incoupling element 100. The emitter 30 may be mounted on the light guide surface or provided on a support (not shown). The emitter may be positioned at a predetermined distance from the incoupling element 100, or it may be in contact with the element and optionally attached to it. In some configurations, the emitter 30 includes a collimation device such as a collimation lens. On the other hand, certain embodiments of the incoupling element 100 are intended to provide a collimation optical system integrated with the element (see Figures 4 and 5).

[0081] The incoupling element 100 is configured to receive and incouple optical radiation 31 (light) emitted from the emitter(s) 30. The element 100 is further configured to adjust the direction of the incoupling light and mediate the propagation of light (light rays 32) through the light guide medium toward the optical outcoupling region(s).

[0082] In some configurations, the optical element 100 uses an optical array (optical pattern). The pattern is formed in the element substrate 100A and can be established in a certain number of feature parts that are configured as optical functional cavities.

[0083] Figure 1C shows a cross-sectional view of an optical incoupling element 100 according to several embodiments. The incoupling element 100 comprises a substrate 100A and at least one pattern 101 formed by a number of pattern feature portions 102 embedded in the substrate. The arrangement of the pattern feature portions 102 in the substrate is preferably periodic, but it is not excluded to provide the pattern 101 as a non-periodic structure. The feature portions 102 are configured as optical functional cavities (i.e., internal cavity optical systems, embedded cavity optical systems, or integrated cavity optical systems). The latter are further referred to as "cavities" or "cavity profiles". The substrate 100A having the embedded pattern(s) 101 / embedded cavity 102 forms an optical functional element structure 1011, which is optionally configured as layers.

[0084] The internal cavity 102 is filled with a filler material having a refractive index different from that of the substrate material surrounding the cavity.

[0085] In some configurations, the cavity 102 is filled with a low refractive index material. Additionally or alternatively, the cavity may have a low refractive index coating. In some configurations, the cavity 102 is filled with air to establish an embedded air cavity optical system solution. Overall, the filling material of the cavity can be established with any one of the following: a gaseous medium including air or other gases, a fluid, a liquid, a gel, and a solid.

[0086] Low refractive index materials are typically materials with a refractive index in the range of 1.10 to 1.41. i The refractive index of the material is typically less than 1.5, preferably less than 1.4. For example, if cavity 102 has a low R i Filled with a medium or low R i If a coating is present, the embedded pattern has an optical filtering function (the spectrum of electromagnetic radiation incident on it). A filter is defined as having the ability to change the intensity distribution or polarization state. Filters can be involved in performing various optical functions, such as transmission, reflection, absorption, refraction, interference, diffraction, scattering, beam splitting, and polarization.

[0087] The optical functional structure 1011 having an embedded pattern 101 is formed of at least two substrate components 1011A and 1011B. In the configuration shown in Figure 1C, these components are provided as at least two (sub)layers. The first substrate component 1011A has a substantially flat plane in which at least one cavity pattern is formed. The patterned layer 1011A may be provided as a layer of flat, planar substrate material of uniform thickness in which at least one cavity pattern is formed. To establish internal cavities and form an embedded optical pattern, the first substrate component having a patterned surface is abutted against the entirely flat plane of the second substrate component 1011B such that at the interface between the patterned substrate surface of the first component 1011A and the entirely flat plane of the second substrate component 1011B, at which are embedded cavities 102 alternating with flat bonding points or bonding regions 103.

[0088] The boundaries between the substrate components or layers 1011A and 1011B are not shown in order to emphasize the nearly "integrated" nature of the optically functional element structure 1011 having the embedded cavity 102.

[0089] In some configurations, the second base material component 1011B is provided as a layer of a base material that is flat and planar overall and has a uniform thickness.

[0090] In some configurations, at least the first substrate component 1011A having a patterned surface is formed from a substantially optically transparent material (e.g., 100A). The second component 1011B may be formed from an optically transparent material and / or a colored material. Substrate components 1011A and 1011B can be made from the same substrate material and / or substrate materials having substantially the same refractive index. Alternatively, the substrate components can be made from different materials, the differences being established at least in terms of refractive index, transparency, color, and associated optical properties (transmittance, reflectance, etc.). For example, the entire optically functional element structure 1011 (including both 1011A and 1011B) can be made from a substantially optically transparent substrate material such as a transparent polymer or elastomer, UV resin, etc. Alternatively, components 1011A and 1011B can be made from different materials with different refractive indices, respectively.

[0091] In the optical pattern 101, regions of the substrate material alternating with the cavities 102 form contact regions or contact points between the structural components (1011A, 1011B) and optionally the optically functional element structure 1011 (see Figures 5, 1012, 1013). Under certain conditions, region 103 forms a so-called optical channel through which light is transmitted internally within the element 100 between the layers (1011, 1012, 1013). The optical channel is formed when the substrate material 100A is a substantially translucent carrier medium. Thus, the pattern 101 includes a number of embedded cavities 102 having contact points / optical channels 103 between them.

[0092] In some embodiments, as shown in Figure 1C, the incoupling element 100 is formed solely of an optical functional structure 1011. Such an incoupling element consists of a structure 1011 (optionally configured as a layer) having a pattern(s) 101 / (air) cavity profile 102 that is completely embedded within the substrate material (no prominent pattern features are established on the outer surface).

[0093] Figure 1D shows a configuration in which an incoupling element 100 is implemented with a number of embedded patterns 101 (101-1, 101-2) arranged in a stacked configuration. The configuration involves forming a multilayer solution in a single element by joining two or more optically functional element structures / layers 1011 (1011-1, 1011-2) to each other. In such a configuration, the patterned layer 1011A may alternate with a flat substrate layer 1011B.

[0094] In some examples, the element 100 may be formed using a laminate comprising two or more patterned layers (referred to as 1011A) arranged on top of each other. The flat, planar interface between the layers may therefore be established by the patterned layer 1011A alone (requiring that the layer establishes a pattern on one of its surfaces, while the other surfaces remain flat overall). The topmost patterned layer may further be provided with a flat substrate layer (referred to as 1011B) to complete the multilayer structure and allow for complete encapsulation of the pattern(s).

[0095] Therefore, the laminate may be implemented using any one of the following: an entirely flat substrate layer (1011B), alternating patterned layers (multiple) (1011A), and an optically functional layer (1011). Patterns located at different levels within the laminate may be configured to perform the same or different optical functions related to incoupling and the adjustment of the direction of light received thereon, the optical functions being selected from the group consisting of incoupling, reflection, direction change, deflection, absorption, transmission, collimation, refraction, diffraction, diffusion, polarization, and any combination thereof.

[0096] Figure 1E shows an exemplary embodiment of an element 100 having an uppermost surface inclined at a predetermined angle. Thus, the element comprises an embedded cavity pattern 101 formed by a patterned component 1011A and an overall flat and planar component 1011B. The patterned component 1011A is given a predetermined shape (for example, such that its cross-section forms a triangle), and component 1011B, which is provided as a flat and planar layer component of uniform thickness such as a coating or film, is laminated onto the patterned component, thereby forming an embedded cavity 102.

[0097] In this configuration, the patterned component 1011A is formed from a substantially optically transparent substrate material 100A. The topmost flat component 1011B is, for example, made of a low refractive index (low R). i It is made of different materials such as ) material. Low R i By bonding a layer containing material to a patterned component, the internal total internal reflection (TIR) ​​efficiency with respect to the critical angle of incident light can be improved.

[0098] Figure 1F shows an element 100 comprising a substrate 100A and an optical tape 10 attached thereto. The tape 10 is a so-called harmonic tape, primarily provided with optical incoupling and direction-changing functions, as well as the optical functions performed by the element 100. An optical (air) cavity pattern(s) is integrated inside the tape 10. The configuration may optionally include providing one or more optical patterns 101 in the substrate 100A, as described in relation to Figure 1E.

[0099] Figure 1G shows an element 100 comprising a substrate 100A and an optical tape 10 positioned below the element (between the element 100 and the light guide 20). Figure 1G illustrates an example of using the optical incoupling and redirection tape 10 to enable optical contact between the incoupling element 100 and the light guide medium 20.

[0100] Overall, the configurations shown in Figures 1F and 1G, which include the provision of an incoupling tape 10, also perform two-phase functions, such as incoupling light to a light guide and redirecting the incoupled light to have a suitable angular distribution (e.g., collimating the light). The tape 10 may be configured for a number of optical functions, such as collimation, linear diffusion, and polarization. The tape is easy to assemble and use.

[0101] Figure 1H shows an optical incoupling element 100 comprising an integrated emitter device 30 (light source). The emitter device can be fully or partially integrated into the substrate material 100a forming the incoupling element 100. The emitter 30 may be embedded inside the optical incoupling element by direct casting or retrofitting to maximize the optical incoupling efficiency. The incoupling element 100 having an integrated and embedded emitter device 30 can be further described as an optical device / unit 250. An integrated emitter device can be provided in any other shape of element 100.

[0102] Figure 1I shows a conventional combination of an incoupling element 100 and an emitter device 30. In this way, an optical unit 250 comprising the incoupling element 100 and a light source 30 is established. The unit 250 may further include a housing disposed around the element 100 and emitter 30. The element 100 and emitter 30 integrated in the unit 250 are optionally enclosed within the housing. Optionally, the housing is open on the side where the element is located on the light guide surface (i.e., the optical contact surface 107). The unit 250 has a height (h) of approximately 0.5 to 10 mm, and any suitable element 100 of any length / width can be used. The established unit provides a robust and reliable incoupling solution for easy and rapid installation and use. The unit 250 may be supplied without a housing.

[0103] The optical unit 250 thus comprises at least one incoupling element 100 and at least one emitter device 30 configured to emit optical radiation incident on an optical pattern 101 within the element. In this way, the unit 250 provides a compact solution in which the light source 1(s) is integrated with the (incoupling) optical system.

[0104] Multiple light sources can be integrated into the same unit. These light sources can be controlled separately and / or in combination. Arrangements including at least two light sources allow for the adaptation of additional lighting characteristics, such as those related to monochromatic or polychromatic illumination. Furthermore, IR and / or UV radiation can be used for additional purposes, such as UV-C radiation for sterilization and disinfection methods. Unit 250 can utilize elements of any other shape.

[0105] Therefore, Figures 1H and 1I illustrate the formation of an optical unit 250 having internal and external light sources, respectively.

[0106] In all configurations (Figures 1A to 1I), element 100 and / or unit 250 may include means for attaching the light guide, such as an adhesive layer.

[0107] In terms of size-related parameters (length, width, height / thickness, inclination, curve), element 100 and / or unit 250 can be configured to achieve optimal performance efficiency.

[0108] The incoupling element 100 preferably has a uniform outer surface without any surface relief patterns or related structures formed thereon. However, current technology does not preclude the manufacture of relief patterns (open cavity patterns). Thus, the absence of protrusions or reliefs allows the incoupling element or its outer surface to be handled without damaging the element optics and light source when attached to a light guide.

[0109] The element 100 can be configured as a discrete three-dimensional item that is given a predetermined optical function by its shape, the provision of optical contact surfaces (multiple possible) 107, and optionally the provision of an optically harmonic tape 10 (for example, Figures 1A, 1B, 1F, 1G, 1H, and 1I). In some cases, the element 100 may be provided with optical patterns (multiple possible), such as embedded optical patterns (multiple possible) (for example, Figures 1C to 1E). However, embedded optical patterns (multiple possible) 101 can be provided in any configuration shown in Figures 1A to 1I.

[0110] Figure 2A is a cross-sectional view of a multi-phase incoupling element 100. The element 100 consists of at least two adjacent functional zones P1 and P2 (phase 1 and phase 2). Each of the zones is independently configured to perform optical functions related to incoupling incident light and adjusting the direction of the incoupling light so that the incoupling light is directed (or redirected) toward the light guide medium 20.

[0111] Figure 1A shows the formation of the functional zone by separate element modules 100P1 and 100P2, respectively. The modules are interconnected by an interface layer 1015, optionally by an adhesive. The interface layer may be formed by a simple mechanical connection between modules 100P1 and 100P2.

[0112] The configuration shown in Figure 2A allows for more efficient optical coupling with a predetermined optical angular distribution. The first phase P1 (module 100P1) can be configured to incouple the incident light and redirect at least a portion of the incident light to the light guide medium with a suitable angular distribution. The second phase P2 (module 100P2) can be configured to complement the optical function of P1 by incoupling the light rays leaking from P1 and redirecting the leaked light back to the light guide medium to achieve a suitable light distribution.

[0113] P1 and / or P2 can be configured to (in)couple light arriving at a given angle of incidence. Multiphase incoupling solutions improve incoupling efficiency and allow control of light incident at a specific angle (relative to the surface normal from which the light is incident).

[0114] The zone / module configuration is not limited to the tapered shape shown in Figure 2A. Any other configuration, such as the rectangular planar elements shown in Figure 1C, can be provided as a modular solution.

[0115] The first-phase element module 100P2 and the second-phase element module 100P2 can differ from each other at least in terms of size and / or shape (see Figure 2A showing modules 100P1 and 100P2 having different shapes). Additionally or alternatively, the differences between element modules can be established by the incoupling optical system, the latter defined by the variable configuration and / or arrangement of the internal cavity, which will be further described below. Thus, element modules 100P1 and 100P2 can have the same size and / or shape and can differ from each other only by the embedded incoupling optical system. ru.

[0116] In some cases, the interface layer 1015 between modules 100P1 and 100P2 has a low R i Provided as an adhesive layer. Low radius. i The interface layer allows for the achievement of the TIR effect at the interface between element modules.

[0117] Figure 2B is a cross-sectional view showing an arrangement including at least two discrete incoupling elements 100-1, 100-2 arranged on a light guide medium 20. The arrangement may include incoupling elements according to those shown in Figures 1A-1I and Figure 2A. The elements in the arrangement may be identical or different. Elements 100-1, 100-2 may be arranged mirror-symmetrically with respect to each other, as shown in Figure 2B, to incouple light from at least one light source. The bidirectional optical incoupling solution allows for light propagation controlled in different directions with respect to the position of the light source. The configuration may utilize one or more emitter devices (e.g., one emitter device with 360° emission, or two or more emitter devices configured to emit light in a predetermined direction). Elements 100-1, 100-2 may be arranged mirror-symmetrically with respect to an array of emitter devices, as shown in Figure 4 (Image B).

[0118] The arrangement in Figure 2B may be modified so that elements 100-1 and 100-2 are positioned at, for example, a 90-degree rotational angle relative to each other around a virtual axis of rotation formed by the position of the emitter device 30. Any other suitable arrangement of elements 100-1 and 100-2 around the emitter device 30 is conceivable.

[0119] Figure 3 shows various layouts of the optical incoupling element 100 on the light guide 20 in (i) to (iv). Layout (i) is substantially the same as that shown in Figure 1B. Layouts (ii) and (iii) show the incoupling element 100 being provided on a planar light guide medium having a conventional single-sided optical outcoupling pattern (ii) and a planar light guide medium having a conventional double-sided optical outcoupling pattern 21 (iii), respectively. Layout (iv) shows the element 100 being provided on a planar light guide medium having a single-sided or double-sided optical outcoupling pattern 21 composed of an embedded cavity optical system (the single-sided configuration is not specifically shown, but can be easily conceived based on ii in Figure 3).

[0120] The optical outcoupling pattern 21 can, for example, be integrated into the light guide medium by duplication, or it can be provided in the form of a coating or tape applied to the surface of the light guide.

[0121] In all of options (i) to (iv), the incoupling element 100 can be provided on one side or both sides of the planar light guide medium. Additionally or alternatively, unit 250 can be used.

[0122] As illustrated with reference to Figures 1C, 1D, and 1E, the optical pattern 101 may be formed along and across the top surface 104 of the incoupling element. The above configuration includes a plane 104 having a uniform height (thickness) or being inclined at a predetermined angle. Due to the planarity of the surface, a substantially planar cavity array (pattern 101) can be manufactured to occupy most of the square surface on the top surface side 104 of the incoupling element. Figure 1A may use a similar cavity pattern arrangement. In this way, the top surface 104 of the element 100 is given optical incoupling function and / or optical distribution control function(s) and forms the primary optical incoupling surface of the element 100.

[0123] Such a solution is most feasible for element 100 formed of planar, arbitrarily inclined structural components (1011, 1011A, 1011B).

[0124] For incoupling elements including a substantially curved surface 104 and / or other curved surfaces (Figures 1B, 1G, 1H, 1I, 2A (100P1), 2B), providing a cavity pattern along and across the entire square surface on the top surface side may be more labor-intensive from a manufacturing (laminating) setup standpoint.

[0125] Figures 4 and 5 show an incoupling element 100 having an embedded optical pattern 101 positioned on the side end face 105 of the optical element facing the emitter device 30. In the element 100 shown in Figures 4 and 5, the primary optical incoupling surface is thus established by the three-dimensionally formed side end face 105.

[0126] During the manufacturing of the element 100 as shown in Figures 4 and 5, a substrate component having a planar patterned surface is optionally joined to a substrate component having a planar and flat surface by lamination, thereby creating an embedded cavity pattern 101.

[0127] In this configuration, the optical interfaces (101, 102) are thus laid out on a plane that lies substantially along the vertical axis (i.e., substantially perpendicular to the horizontal plane that defines the position of the light guide). In comparison, in a configuration that includes the uppermost surface 104 as the primary optical incoupling surface, the optical interfaces (101, 102) are laid out on a plane that lies substantially along the horizontal axis (i.e., substantially parallel to the plane that defines the position of the light guide, including the necessary tilt angle correction).

[0128] The provision of optical patterns as shown in Figures 4 and 5 is particularly suitable for constructing integrated collimation optics, such as embedded cavity optics for conical (horizontal) optical collimation.

[0129] In Figure 4, the direction of the taper (showing a downward slope) is indicated by an arrow (surface 104).

[0130] Figure 5 shows a tapered element 100 having a pattern 101 adapted for collimation functionality. Images B and C show elements 100 having embedded collimation cavities 102 of different lengths / heights. In option B, the collimation cavity 102 is short compared to the distance between the top and bottom surfaces of the element 100 (i.e., the height or thickness of the element). In option C, the cavity extends almost through the entire element. The cavity is embedded throughout.

[0131] Additional optical performance can be achieved by implementing a cavity profile, such as a longitudinal groove, on the uppermost surface (104) of the taper 100 (see Figure 1E, which shows a cross-section of a V-groove shaped cavity profile). Collimation solutions may further include, for example, providing a reflective layer on a specific surface of the embedded (air) cavity.

[0132] By modifying pattern-related and / or cavity-related parameters, other optical functions can be achieved in addition to, or as an alternative to, collimation.

[0133] Overall, the provision of optical patterns 101 along and across the three-dimensionally formed optical functional surfaces 104, 105 may differ between embodiments. Either one of the elements and / or element modules (Figure 2A) may be mounted with optical patterns(s) located along one or both of the surfaces 104, 105. For example, The Joule solution (Figure 2A) may include a first element module (100P1) containing a first pattern 101 arranged along surface 105, and a second element module (100P1) containing a second pattern 101 arranged along surface 104.

[0134] In this regard, in addition to the primary incoupling surface, a secondary incoupling surface can be identified within the element 100. For example, if the primary incoupling surface is formed by an embedded optical pattern 101 provided on the side end surface 105 (Figures 4 and 5), the secondary incoupling surface may be formed by a pattern integrated with the embedded optical pattern 101 and / or optical incoupling tape 10 provided on the surface 104, as shown in Figures 1F and 1G.

[0135] Alternatively, the aforementioned surfaces 104, 105 and element 100 may be mounted without patterns.

[0136] For the purposes of the present invention, it is essential that light reaches at least one three-dimensionally formed optical surface 104, 105 and optionally one or more optical patterns 101 from a direction substantially parallel to the longitudinal plane of the planar light guide (i.e., the light travels substantially along the longitudinal direction of the light guide). This is achieved by positioning the emitter device 30 relative to the side end face 105 of the element (while the element 100 is located on the light guide). The emitted light enters the element substantially through the side end face 105 and enters the optical surface 104, 105 and optionally one or more optical patterns 101 from a direction substantially parallel to the plane of the light guide. The side end face 105 may function as a primary incoupling surface using the optical pattern (Figures 4 and 5).

[0137] The elements are configured and positioned on the light guide such that almost all light emitted by the emitter device(s) enters the optical incoupling element, and almost all light received by the incoupling element is incoupled to the light guide. Therefore, the light emitted from the emitter device(s) enters the optical incoupling element and does not enter the edge (or end) of the light guide.

[0138] In addition to the optical coupling surfaces 104, 105, the element 100 may include an additional shaping profile 106 (Figs. 5, A, B, C). The profile 106 may extend along about 20 - 40%, preferably about 30% (when viewed horizontally along the longitudinal plane of the light guide) of the length of the element 100. The profile 106 may be implemented as a wedge between the element surface facing the light guide (i.e., the optical contact surface 107) and the light guide medium 20. The wedge form enables improved light management and improved light direction conversion characteristics and accounts for about 10% of the improvement in optical efficiency. In the case of the angular wedge profile 106, the upper surface of the wedge defined by the lower surface of the element 100 is positioned at a predetermined angle with respect to the light guide surface (as shown in Fig. 5). Alternatively, the profile 106 may have an overall flat surface without forming an optical contact on the light guide surface. The wedge profile 106 may be defined by an air medium or any other arbitrary low R i medium. The profile 106 may be further coated with a suitable coating material, such as a low R i coating.

[0139] In addition to the optically functional element structure 1011 discussed herein, the incoupling element 100 may be provided with several additional functional layers, such as a base layer shown as 1012 (see Images A, B) and a top layer shown as 1013 (see Image D) in Fig. 5. Similarly, the layers 1012, 1013 may be arranged on one of the two sides (upper and lower) of the mounted element as shown in Figs. 1A - 1I, 2A, 2B. These layers impart several additional functions to the element 100.

[0140] For example, the base layer 1012 may be configured as an adhesive layer to enable adhesion to the light guide medium of the lower layer. The adhesive layer 1012 may be provided as an optically transparent adhesive (OCA) or a liquid optically transparent adhesive (LOCA). The optically transparent adhesive layer may be established by an acrylic or silicone adhesive. The adhesive layer is typically provided on the underside of the element 100, but it is not excluded to provide the adhesive on any surface or both sides (top and bottom) of the element.

[0141] A base layer 1012, provided as an optically transparent adhesive (OCA) layer, causes the incoupling element to make optical contact with the light guide 20. The contact interface is preferably established by the plane of the light guide and optionally by the optical contact surface 107 of the element having the adhesive layer 1012.

[0142] The top / outer layer 1013 is an optically transparent layer, an opaque layer, a specular or diffuse reflector layer, or a low refractive index (R i It may be provided as a functional outer layer configured as one of the following: a layer, etc. Alternatively, the top layer 1013 may be configured as an adhesive layer similar to the base layer 1012.

[0143] In some configurations, the optical incoupling element is configured to perform collaborative multifunctions, where light directionality and wavelength management are performed, for example, by an integrated wavelength conversion layer, and monochromatic light, such as blue LED light, is partially or completely converted.

[0144] In some configurations, the optical incoupling element includes additional functional layers (1012, 1013) configured as wavelength conversion layers for partial or complete conversion of monochromatic light, such as blue (LED) light. The wavelength conversion layers can be located on the upper and / or lower surfaces of the light guide. In the latter case, the wavelength conversion layers can be located together with an adhesive layer to form an optical connection with the light guide. This additional conversion layer can be utilized on the edge of the light guide or on a planar region (the light distribution region of the light guide).

[0145] Alternatively or additionally, a wavelength conversion layer can be used in conjunction with an incoupling (harmonic) tape 10.

[0146] For example, one of the additional layers (e.g., 1012, 1013) may be configured as a black layer that absorbs some of the light passing through the optical path (103), forming a contact point at the interface between the layers. The black layer coating may be provided, for example, on the back side of the optical element. In another exemplary configuration, the additional layer(s) may be an optically transparent layer that transmits light passing through the contact point 103 at the interface between the layers (1011, 1012, 1013). As described above, the contact point (optical path) is formed by the substrate region 103. Similarly, any of the additional layers may be configured as a reflector layer, and the material of the layer may be employed to produce specular reflection, Lambertian reflection, or any other reflective opaque material.

[0147] One special solution is a low refractive index (R i This includes utilizing the ) layer as the top-level additional functional layer 1013. The shown solution typically improves the light intensity distribution / optical harmonic efficiency by about 6% to about 20%, depending on the fill factor and shape of the interconnection point (contact region 103).

[0148] One or more additional layers may be provided on the top and / or bottom surfaces of the element. Therefore, in addition to the adhesive layer 1012, the underside of the element 100 may have, for example, a black layer or a low-radius layer. i A layer (not shown) may be provided. The described configuration needs to be adjusted on a case-by-case basis, taking into consideration, for example, the position of element 100 on the light guide medium and whether the element is provided as small discrete elements such as a band or strip, or as an elongated continuous element.

[0149] Figure 6 shows a combined optical incoupling solution using an incoupling element 100 and a harmonic tape 10 positioned on the light guide 20 following the incoupling element 100 (relative to the emitter 30).

[0150] Tape 10 is described below. The optical tape 10 shown in Figure 6 can generally be used in the solutions described in relation to Figures 1F and 1G. By changing pattern-related and / or cavity-related parameters, the tape 10 can be given a predetermined distinct optical functionality. Thus, the tape configuration shown in Figures 1F and 1G, which includes the tape 10 provided above the element 100 and / or between the element 100 and the light guide, can be advantageously used for optical incoupling and direction conversion, while the tape configuration shown in Figure 6 is particularly suitable for light distribution control.

[0151] Therefore, a harmonic tape 10 primarily given an incoupling function (used in the manner shown in Figures 1F and 1G) is called an "incoupling tape," while a harmonic tape 10 primarily given a light distribution control function is called a "deflection tape."

[0152] From a structural standpoint, the deflection tape 10 largely follows the principle described above in relation to the element 100. The tape 10 is composed of an optical functional layer 111 having at least one embedded pattern 11 formed on a substrate 10A. The optical functional layer 111 is formed from (sub)layers 111A and 111B. The first substrate layer 111A has a substantially flat plane therein in which at least one cavity pattern is formed (hereinafter referred to as the patterned layer). The patterned layer 111A can be provided as a flat, planar substrate material layer having a uniform thickness in which at least one cavity pattern is formed. To establish internal cavities and form an embedded optical pattern, a first substrate layer having a patterned surface is abutted against the overall flat plane of a second substrate member 111B so as to form at least one embedded cavity pattern 11 having embedded cavities 12 alternating with flat bonding points or bonding regions 13 at the interface between the patterned substrate surface of the first layer 111A and the overall flat plane of the second substrate layer 111B.

[0153] A multilayer configuration can be conceived by arranging the pattern 11 (layer 111, tape 10) as a laminate in the same manner as described above with reference to element 100. The embedded pattern 11 comprises embedded (air) cavities 12 that alternate with flat bonding regions 13 that optionally form optical pathways. The formation of optical pathways from the bonding regions depends on the refractive index of the substrate material forming the sublayers 111A and 111B, and the provision of an optional interface coating between the sublayers. Thus, the sublayers 111A and 111B may be formed from the same substrate material 10A or from different materials.

[0154] The tape 10 may further comprise additional functional layers (one or more) 112, 113 corresponding to the additional functional layers 1012, 1013 of the element 100 according to their function (see Figure 5). The tape 10 may also have a base layer 112 provided as an adhesive layer for mediating the adhesion of the tape to the light guide medium and / or the underlying element substrate, and optionally a top layer 113 (see configuration in Figure 1G).

[0155] The use of the tape 10 in combination with the incoupling element 100 improves the light distribution through the light guide, particularly in the vertical axis, but also in the horizontal axis. Depending on the tape configuration and pattern design, it is possible to control (narrow or widen) the light distribution within the light guide with high precision.

[0156] The optical function of tape 10 is adjustable in terms of cavity-related parameters and tape-related parameters (e.g., substrate material, overall implementation, etc.) as described herein. Overall, providing harmonic tape 10 makes it possible to improve the uniformity of the internal light distribution in the light guide (mediated by the enhanced TIR function enabled by harmonic tape 10).

[0157] The incoupling element 100, optionally in combination with the harmonic tape 10, incouples optical radiation emitted from at least one emitter device 30 and adjusts the direction of optical radiation incident on three-dimensional optical (incoupling) surfaces 104 and / or 105, which optionally include patterns 101. It is essential that the light reaches the incoupling surfaces and optical patterns 101 from a direction substantially parallel to the longitudinal plane of the planar light guide. To achieve this, the emitter device 30 is positioned on the light guide with respect to its side end face 105 (i.e., not above or below the element located on the light guide). The emitted light is incident on the element substantially through the side end face 105 and incident on the optical patterns 101 from a direction substantially parallel to the plane of the light guide. The side end face 105 may have an optical pattern (Figures 4 and 5).

[0158] The element 100 is configured to incouple the incident light with at least one three-dimensionally formed optical surface (104, 105) and adjust / change the direction of the incoupled light that passes through the optical contact surface 107 provided at the interface between the element substrate 100A and the light guide medium 20, thereby causing the incoupled light to obtain a propagation path through the light guide medium via a series of internal total internal reflections.

[0159] In particular (but not limited to), in configurations of a solid without a cavity pattern that include discrete elements, the incoupling light is redirected at the interface between the three-dimensionally formed incoupling surfaces 104 and / or 105 and the surroundings, and / or at the interface between the element substrate 100A and the light guide medium 20 (the latter formed by the optical contact surface 107), thereby obtaining a propagation path through the light guide. As a result, the angle of incidence at the interface between the light guide medium and the surroundings is greater than or equal to the critical angle of internal total internal reflection.

[0160] Additionally or alternatively, element 100 is configured to adjust / modify the direction of received light such that light incident on pattern(s) 101 is deflected and redirected to obtain a propagation path through a series of internal total internal reflections into the light guide medium 20. By providing an optical tape 10 following element 100, the light distribution within the light guide 20 can be controlled more efficiently.

[0161] Pattern(s) 101 (element(s) 100) and optionally pattern(s) 11 (tape(s) 10) are designed such that, by the pattern(s), element(s) 100 and tape(s) 10 mediate incoupling light propagation through the light guide medium (and optionally toward outcoupling region(s) 21), and optionally control the distribution of light propagating through the light guide(s) 20.

[0162] Overall, the element reaches element 100 and includes an in (optionally) pattern(s) 101 located on either the primary or secondary incoupling surface. The direction of the light being incoupled (by coupling surfaces 104, 105) is adjusted to obtain an initial propagation path through the light guide (via TIR). To further support and control the light distribution throughout the entire length of the light guide most efficiently, an optical tape 10 can be provided on the light guide 20. Figure 7 is a ray tracing model for incoupling light to the light guide 20 using an incoupling element 100 and tape 10 optically connected (bonded) to the plane of the light guide 20.

[0163] Therefore, the light 31 received by the element pattern(s) 101 is incoupled and directed (or redirected) at the interface between each cavity 102 and the substrate material 100A surrounding the cavity. In this way, the pattern 101 and its feature parts (cavities) perform an optical function or group of functions related to incoupling and adjusting the direction of the light received therein. As the incoupled and directed (or redirected) light 32 obtains a propagation path through the light guide medium, the angle of incidence at the interface between each cavity and the substrate material surrounding the cavity becomes greater than or equal to the critical angle of internal total internal reflection.

[0164] The optical functions related to controlling the distribution of light propagating through the light guide medium are further supported and controlled by the optical tape pattern(s) 11.

[0165] By assigning a number of parameters to individual cavities or groups of cavities within a pattern, including but not limited to dimensions (size), shape, cross-sectional profile, orientation and position within the pattern, fill factor, and periodicity, any one of the element pattern 101 or tape pattern 11 becomes optically functional.

[0166] The fill factor (FF), defined by the percentage (%) ratio of optical feature portions (102 in element 100, 12 in tape 10) per unit area, is one of the important parameters when designing optical solutions. The fill factor defines the relative proportion of feature portions 102 in a reference area (e.g., one pattern or any other reference area).

[0167] The cavity feature area can be further characterized by several parameters, such as the length, width (top width, bottom width), and height of the feature area, as well as the length and inclination angle of the period.

[0168] Therefore, the primary optical function performed by the optical incoupling element 100, optionally in combination with the optical harmonic tape 10, is to incouple light reaching the incoupling surfaces 104, 105 which optionally include optical patterns 101, 11 along the horizontal direction (parallel to the light guide 20), and to mediate the propagation of the incoupled light within the light guide medium in a predetermined angular distribution. Either the element 100 or the tape 10 may be located below and / or above the light guide medium.

[0169] The following description pertains to the optical element 100. Similar provisions are also applicable to the optical tape 10, therefore, further explanation of the tape-related cavity patterns is omitted.

[0170] Thus, each cavity within the pattern constitutes a profile having a certain number of optically functional surfaces. For illustrative purposes, optically functional surfaces 1021, 1022, and 1023 (hereinafter referred to as the first, second, and third optically functional surfaces, respectively) are schematically shown in Figure 4 (Image A). Each of these surfaces is located at the boundary interface between the cavity 102 and the surrounding substrate medium 100A. In practice, all surfaces within the cavity may be optically functional.

[0171] The optical functional surface(s) are thus established by any(s) surfaces formed at the interface between each cavity and the material of the substrate surrounding the cavity.

[0172] In some configurations, each of the optical functional surfaces (one or more) in the individual cavities within the pattern is established by one of the following: a low refractive index reflector, a polarizer, a diffuser, an absorber, or any combination thereof. Thus, one of the optical functional surfaces (1021, 1021 and 1022) is low R i Appropriate coatings, such as those found in coatings, can be applied during the manufacturing process.

[0173] As described above, one of the main functions of the optical incoupling element 100 is the incoupling and direction (or redirection) of light incident on the pattern at an incident angle greater than the critical angle for internal total internal reflection. The optical function performed by the element is applied to light incident on the pattern (incident at the interface between the cavity and the surrounding medium). The incident light is incoupled and further deflected (redirected) by a certain angle from its original propagation path by the (air) cavity optical system embedded inside the element.

[0174] In addition to regulating the distribution of TIR-mediated light propagation through the light guide medium, the element 100 is configured to perform a number of additional optical functions. Here, a particular function or combination of functions is determined by a number of factors, including related parameters of the cavity and surrounding materials, such as the configuration of the cavity profile(s) in the pattern and the selection of materials (e.g., the substrate material forming the optical functional layer 1011, the materials for the additional layers 1012 and 1013, and the cavity filling material).

[0175] In the element 100, at least one pattern is configured to perform an optical function related to incoupling light emitted from at least one emitter 30 and adjusting the direction of light received therein. Herein, the optical function includes, but is not limited to, reflection, absorption, transmission, collimation, refraction, diffraction, polarization, and any combination thereof.

[0176] The cavities within a pattern perform one or more optical functions individually or collectively. Therefore, the pattern may be configured such that all cavities within the pattern perform the same function (collective performance). In such a case, the pattern may consist of the same (identical) cavities. Alternatively, each individual cavity 102 within the same pattern may be designed to establish at least one optical function related to the adjustment of the direction of light received therein. This is achieved by adjusting cavity-related parameters such as dimensions, shape, cross-sectional profile, orientation, position, periodicity, and fill factor (during the design and manufacturing phases), as described above. The element 100 can consist of a number of patterns, where each pattern consists of feature parts / cavities that differ from any other pattern(s) within the element in terms of at least one parameter.

[0177] In element 100, the pattern(s) are variably configured by a certain number of cavity-related parameters, the certain number of cavity-related parameters including individual parameters or any combination of parameters selected from the group consisting of dimensions, shape, cross-sectional profile, orientation, position, and periodicity.

[0178] In element 100, the cavity is established by a two-dimensional or three-dimensional pattern feature having a cross-sectional profile selected from the group consisting of linear, rectangular, triangular, blazed, inclined, trapezoidal, curved, wavy, and sinusoidal profiles.

[0179] The achievement of incoupling and direction (or direction change) functions is aided by providing optical path regions 103 between cavities 102 (Figure 1C). The configuration of the optical path largely depends on the configuration of the cavities and their arrangement in the pattern, but for example, the light transmission characteristics can be controlled and optimized by the selection of the substrate material.

[0180] Incoupling light to which an optical direction-changing function is applied (i.e., incoupling rays whose direction is adjusted through interaction with the cavity pattern), also called deflected and / or directed (or direction-changed) light (32, Figures 1A-1I), obtains a propagation path through the light guide medium 20 via a series of internal total internal reflections.

[0181] The patterns (or multiple patterns) 101 in the tape can be further adjusted so that light is incident on the patterns (or multiple patterns) when the angle of incidence at the interface between each cavity in the pattern and the material of the substrate surrounding the cavity is greater than or equal to the critical angle of internal total internal reflection. With this arrangement, the direction of the light received by element 100 and element (or multiple patterns) 101 (from a direction substantially parallel to the longitudinal plane of the planar light guide 20) is changed at the interface between each cavity in the pattern and the material of the substrate surrounding the cavity to obtain a propagation path through the light guide medium. As a result, the angle of incidence at the interface between the light guide medium and its surroundings, and optionally, the angle of incidence at the interface between each cavity and the material of the substrate surrounding the cavity, are greater than or equal to the critical angle of internal total internal reflection.

[0182] By providing a combination of an incoupling element 100 and a deflection tape 10 optionally placed following the element 100, the direction of the incoupling light is further adjusted so that the light reaches the plane of the boundary (interface) between the light guide medium and its surroundings, and optionally, the plane of the boundary (interface) between each cavity and the substrate medium surrounding the cavity, at an incident angle greater than the critical angle of internal total internal reflection.

[0183] For clarity, the term “deflection” is used herein primarily in reference to incoupling rays whose direction is adjusted / changed in element 100 and / or tape 10 (i.e., changed to deviate from the original path emitted by the emitter), while the term “direction (or transformation)” applies to both rays that are deflected (direction-changed) in the tape and rays that, after being deflected in the tape, obtain a propagation path through a series of TIRs via the light guide. Both the deflection and direction (or transformation) functions aim to adjust the direction of optical radiation as a result of light interacting with interface / boundary materials (e.g., air-plastic). This interaction occurs through a number of optical functionalities, such as reflection and refraction.

[0184] When light reaches the pattern at an incident angle within a certain range, it undergoes total internal reflection in the cavity 102. Therefore, the cavity 102 can be configured to receive and further distribute light that reaches the pattern (at an incident angle greater than or equal to a critical angle with respect to the interface formed by any one of the optical functional surfaces) from the perspective of the functional surfaces 1021, 1022, and 1023.

[0185] When a light ray travels through an optically transparent substrate 100A and strikes one of the internal cavity surfaces (1021, 1022) at a certain angle, the ray is either reflected from that surface to the substrate or refracted into the cavity at the cavity-substrate interface. The conditions under which a light ray is reflected or refracted are determined by Snell's law, which describes the relationship between the angle of incidence and the angle of refraction of a light ray incident at the interface of two media with different refractive indices. Depending on the wavelength of the light, at a sufficiently large angle of incidence (exceeding the "critical angle"), no refraction occurs, and the light energy is confined within the substrate.

[0186] The critical angle is the angle at which the phenomenon of total internal reflection occurs, relative to the surface normal. The angle of incidence becomes the critical angle when the angle of refraction is 90 degrees relative to the surface normal (i.e., the critical angle). (It becomes equal to). Typically, a higher refractive index (R i ) from a medium with a lower refractive index (R iWhen light passes through a medium, for example, plastic (R i 1.4~1.6) and glass (R i 1.5) From air (R i 1) When light passes through a medium with a nearly low refractive index, TIR occurs. i Low R from media i When the angle of incidence (e.g., at the glass-air interface) is greater than the critical angle for light rays traveling through a medium, the medium boundary acts as a very good mirror and the light is reflected (high R such as glass). i (Returning to the medium). When TIR occurs, no energy is transferred across the boundary. On the other hand, light incident at angles less than the critical angle (multiple angles are possible) has high R i Part of the light is refracted and part is reflected from the medium. The ratio of reflected to refracted light depends largely on the angle of incidence and the refractive index of the medium.

[0187] The critical angle varies depending on the substrate-air interface (e.g., plastic-air, glass-air, etc.). For example, for most plastics and glasses, the critical angle is approximately 42 degrees. Therefore, in an exemplary waveguide, light incident at a 45-degree angle (relative to the surface normal) at the boundary between a translucent medium such as a PMMA sheet and air would likely be reflected back by the light guide medium, thereby preventing light outcoupling.

[0188] The same principle applies to light traveling through a light guide medium via a series of TIRs. Note that TIR-mediated light propagation through the light guide can occur even outside the boundary defined by the incoupling element 100. The TIR phenomenon is established by the light guide design and the selection of the light guide medium.

[0189] Two-dimensional or three-dimensional patterns are typically established to have constant-periodic pattern features or variable-periodic pattern features. Periodicity is a necessary feature to control and deflect plane waves in the light guide medium, thereby redirecting incident light (i.e., light incident on the pattern) for a desirable distribution. In further cases, non-periodic pattern features may be used to harmonize non-uniform luminous flux and / or light distribution.

[0190] In each individual pattern, the cavity 102 can be established by discrete or at least partially continuous pattern features. Examples of discrete patterns include dots and pixels.

[0191] Overall, the incoupling element 100 is based on two- and three-dimensional optical systems that utilize integrated and embedded optical features, such as a periodic grating pattern in the form of a TIR surface and a hybrid pattern including a main profile and optionally subprofiles, embodied as a fully embedded cavity optical system within a medium, optionally such as a layer. The incoupling element solution 100 typically utilizes at least two or more optical functions related to light propagation, direction conversion, and transmission. Here, the main optical profile surface may optionally include optical sub-feature areas that realize the optical pattern with additional optical functions such as diffusion, anti-reflection, diffraction, scattering, beam splitting, and polarization. The shape of the profile and its function determine the final performance target.

[0192] Figure 8A schematically shows the implementation of an incoupling solution by combining an incoupling element 100 in the shape of a tapered element with a tape 10 assembled on a light guide 20. Configuration (i) is in which a tape 10 having an optical functional layer 111 with a pattern 11 is laid along a predetermined length of the tape (indicated by an arrow). The tape 10 has a base adhesive layer (not shown) and a low radius laid along the entire length of the tape. iThe tape 10 is equipped with a coating 113. i This includes areas with a coating but does not have pattern 11. The numerical values ​​are in millimeters (mm).

[0193] Configuration (ii) includes a special, segmented tape solution. Within the pattern (Figure 8A, ii), the cavities are configured and arranged to form a substantially variable (or segmented) periodic pattern, and each local pattern design has a feature that is substantially variable from other local designs within that pattern. In some configurations, the tape 10 comprises a number of patterns arranged as periodic segments A, B, C, each segment having a predefined area and period length. These local patterns can be made variable by changing pattern and / or cavity-related parameters to control the light incident thereon at a given angle or range of angles. The cavity profile can be configured variably in terms of a number of parameters selected from any one of the following: dimensions, shape, cross-sectional profile, orientation, and position within the pattern.

[0194] Similar to the incoupling element 100, in the tape 10, the cavity is established by a two-dimensional or three-dimensional pattern feature having a cross-sectional profile selected from the group consisting of linear, rectangular, triangular, blazed, inclined, trapezoidal, curved, wavy, and sinusoidal profiles.

[0195] Regarding the configuration and arrangement of the pattern(s), the tape 10 is designed and optimized for a specific light guide thickness and other light guide-specific parameters.

[0196] Within tape 10, a certain number of patterns, arbitrarily arranged as segments, can be configured to form a single functional zone (Figure 8A, i). Alternatively, a certain number of patterns, arbitrarily arranged as segments, can be configured to form a certain number of adjacent functional zones. Configuration (ii) in Figure 8A shows the formation of three functional zones, which are established by segments A, B, and C. In the latter case, each zone, or a group of adjacent or non-adjacent zones, can have a characteristic cavity profile to efficiently manage light incident at a specific angle.

[0197] Figures 8B and 8C are comparative graphs illustrating the vertical light distribution (YZ plane) in a planar light guide when only a tapered incoupling element 100 is provided (Figure 8B) and when it is used in combination with the tape 10 (Figure 8C). In the solution of Figure 8C, which utilizes the tape 10, the tape 10 is provided immediately after the incoupling element 100, as shown in Figure 8A(i). Curve 2 shows the input light (emitted light before interaction with any optical element), and curve 1 shows the output light after interaction with the optical element 100 and the tape 10. The sum of points relative to curve 2 (input light) is 100%.

[0198] The configuration in Figure 8B, with a vertical FWHM of 98°, enables an efficiency of 95.7%, while the configuration in Figure 8C, with a vertical FWHM of 68°, enables an efficiency of 86%.

[0199] Figure 8C shows that the light distribution within the light guide medium is harmonized by the tape 10. The narrower distribution of light entering the light guide improves the contrast ratio of the light guide during optical outcoupling. Consequently, the transparency of the unilluminated side of the light guide improves.

[0200] Figure 9 shows a planar light guide that includes a tapered incoupling element 100 in combination with a tape 10, as shown in Figure 5, with a tapered element 100 having an optical wedge profile 106 on the light guide contact surface, in the vertical (YZ plane) and horizontal ( This graph illustrates the light distribution in the XZ plane. Element 100 is configured to enable conical collimation by an embedded cavity pattern 101. The cavity pattern (1011A) has a specular reflector layer (1011B) laminated on top of the pattern layer (one side). Furthermore, this element is provided with an anti-reflective (AR) coating 1013 on its surface. Curve 2 shows the input light (emitted light before interaction with any optical component), and curve 1 shows the output light after interaction with the optical element 100 and the tape 10.

[0201] This configuration, with FWHM horizontal 29° and FWHM vertical 60°, enables 78% efficiency.

[0202] Figures 10A and 10B illustrate the effects achieved by a tapered element 100 without a collimation pattern and by an optical incoupling solution including the same element with a collimation pattern, relating to the illuminance (internal intensity) distribution inside the light guide medium 20. The collimated tapered element 100 (Figure 10B) is implemented according to the method shown in Figure 4 (the location of the cavity pattern 101 within the element 100 is indicated by a dashed-line frame). Both solutions utilize a tape 10 placed following the element 100. Both solutions use a Lambert light source 30.

[0203] The configuration in Figure 10A allows for an efficiency of 81%, with FWHM horizontal 73° and FWHM vertical 77°. The configuration in Figure 10B (including the collimation optics) allows for an efficiency of 82%, with FWHM horizontal 47° and FWHM vertical 72°.

[0204] The above description refers to an incoupling element 100, which has a predetermined shape and is provided as a discrete three-dimensional object / profile that can be measured in three different dimensions / directions (length, width, and height / thickness).

[0205] In some configurations, the optical incoupling element 100 can be supplied in the form of a narrow, elongated band or strip. Elements configured as strips can further be supplied in the form of a roll, for example, wound around a reel. Such rolls can be manufactured by a roll-to-roll lamination process.

[0206] An optical incoupling unit 250 using such an elongated strip-shaped element 100 and at least one emitter device 30 can be considered accordingly (see Figure 11, A, B, C).

[0207] Figure 11 shows different light guide solutions (top view) with assembled optical incoupling units. Configuration A shows optical coupling by element 100 or unit 250 at the top of a window (light guide medium 20) with unidirectional light propagation. Configuration B shows optical incoupling by element 100 or unit 250 with unidirectional and bidirectional light propagation at the top, bottom, and center of the window. The central unit 250 may utilize, for example, the incoupling element solution shown in Figure 2B. Configuration C shows optical incoupling by element 100 or unit 250 on the left and right sides of the window with unidirectional light propagation.

[0208] Configuration D then illustrates an incoupling element 100, provided as part of a discrete, substantially circular unit 250 positioned in the central region of the window and configured for multi-directional light propagation. Such a configuration enables 360° light emission and propagation. The T250 may, for example, be dome-shaped.

[0209] The incoupling element 100, optionally provided as part of the incoupling unit 250, is easy and quick to install. The element 100 may be configured as a flexible (i.e., bendable) strip wound on a reel, or as a durable profile having a predetermined length for different targets.

[0210] In another aspect, the present invention relates to a method for manufacturing an optical incoupling element 100, provided in the form of a discrete optical functional item comprising a substrate and at least one three-dimensionally formed optical surface having at least one pattern formed on the substrate. The method includes manufacturing a master tool for the pattern by a suitable manufacturing method and transferring the pattern onto the element substrate to produce a patterned substrate.

[0211] The patterns can be fabricated by any suitable method, including but not limited to lithography, 3D printing, micromachining, laser engraving, or any combination thereof. Other suitable methods may also be utilized.

[0212] In some configurations, the method further includes applying an additional flat, planar substrate layer on the patterned substrate to generate one or more embedded cavity patterns, such that internal cavities are formed at the perfectly flat, planar interfaces between the substrate layers.

[0213] In some cases, the embedded cavity pattern(s) is produced by a roll lamination method such as roll-to-roll lamination, and the sublayers 1011A and 1011B are laminated to each other to form the optical functional layer 1011. The substrate layers 1011A and 1011B can be joined by a lamination method selected from roll-to-roll lamination, roll-to-sheet lamination, or sheet-to-sheet lamination. Roll lamination is particularly applicable for manufacturing flexible element solutions such as elongated strip-like solutions.

[0214] Once a pattern has been created, it is advantageous to further duplicate it by any suitable method, such as imprinting, extrusion, or 3D printing. Any other suitable method may be used.

[0215] A typical production line is employed to carry out the following processes: a) pattern creation and duplication, b) cavity lamination, c) preparation and lamination of other / additional layers, and d) cutting of the final film. This production line can also be employed for the manufacture of narrow or wide tape products.

[0216] The present invention further relates to a light guide comprising an optically transparent medium 20 configured to establish a path for light propagation through the light guide, and an optical incoupling element 100 and / or incoupling unit 250 configured according to the embodiments described herein, wherein the optical incoupling element and / or unit is attached to at least one plane of the light guide. In some configurations, the optical incoupling element / unit is attached to the light guide by adhesive.

[0217] Further uses of the light guide in lighting and / or display are provided. The light guide is used for decorative lighting, light shields, masks, windows, facades and ceiling lighting. It can be used for lighting and display-related purposes, including but not limited to public and general lighting, signage, billboards, posters and / or advertising board lighting and displays, and solar applications.

[0218] It will be apparent to those skilled in the art that the basic concept of the present invention is intended to cover various modifications as the technology advances. Therefore, the present invention and its embodiments are not limited to the examples described above, but rather can be broadly modified within the scope of the appended claims.

[0219] References 1.Bernard C. Kress, “Optical waveguide combiners for AR headsets: features and "limitations", Proc. SPIE 11062, Digital Optical Technologies 2019, 110620J (16 July 2019). 2.Moon et al., “Microstructured void gratings for outcoupling deep-trap guided modes," Opt. Express 26, A450-A461 (2018). 3. Carlos Angulo Barrios and Victor Canalejas-Tejero, "Light coupling in a Scotch tape waveguide via an integrated metal diffraction grating," Opt. Lett. 41, 301-304 (2016).

Claims

1. An independent optical functional component, an optical incoupling element for a light guide, Substrate and A three-dimensionally formed optical surface comprising at least one optical pattern formed in the substrate and configured as an optical functional cavity, wherein the optical surface comprises at least one optical pattern formed by a plurality of periodic pattern feature portions configured as optical functional cavities. Equipped with, The at least one three-dimensionally formed optical surface is configured to incouple incident light and generate incoupled light, and to adjust the direction of the incoupled light transmitted through an optical contact surface established at the interface between the substrate and the light guide medium, thereby causing the incoupled light to obtain a propagation path through the light guide medium via a series of internal total internal reflections. The optical incoupling element is configured to receive light on the at least one three-dimensionally formed optical surface from a direction parallel to a plane including the longitudinal direction of the light guide medium, thereby so that all light emitted by the emitter device is incident on the optical incoupling element and all light received by the incoupling element is incoupled to the light guide medium, and the optical incoupling element is attachable to at least one plane of the light guide medium.

2. The optical incoupling element according to claim 1, wherein the light emitted from the emitter device is incident on the optical incoupling element but not on the edge of the light guide medium.

3. The incoupling light is redirected at the interface between the three-dimensionally formed optical surface and the surroundings and / or the interface between the substrate and the light guide medium to obtain the propagation path through the light guide medium, and as a result the angle of incidence at the interface between the light guide medium and the surroundings is greater than or equal to the critical angle of internal total internal reflection, as described in claim 1 or 2.

4. An optical incoupling element according to any one of claims 1 to 3, comprising at least one optical pattern formed by an optical functional cavity completely embedded in the substrate, the optical functional cavity being filled with a material having a refractive index different from that of the substrate material surrounding the optical functional cavity.

5. The optical incoupling element according to claim 4, referencing claim 3, wherein the at least one optical pattern is configured to incouple incident light and redirect the incoupled light at the interface between each optical functional cavity and the substrate material surrounding the optical functional cavity, thereby allowing the incoupled light to obtain the propagation path through the light guide medium, and the angle of incidence at the interface between the light guide medium and the surroundings, and optionally the angle of incidence at the interface between each optical functional cavity and the substrate material surrounding the optical functional cavity, is greater than or equal to the critical angle of internal total internal reflection.

6. The optical incoupling element according to any one of claims 1 to 5, wherein the at least one three-dimensionally formed optical surface and the at least one optical pattern are configured to perform an optical function related to adjusting the incoupling and direction of received light, the optical function being selected from the group consisting of reflection, absorption, transmission, collimation, refraction, diffraction, polarization, and any combination thereof.

7. The optical incoupling element according to any one of claims 1 to 6, wherein each optical functional cavity in the at least one optical pattern has a certain number of optical functional surfaces.

8. The optical incoupling element according to claim 7, wherein the optical functional surface(s)

9. The optical incoupling element according to any one of claims 1 to 8, wherein the three-dimensionally formed optical surface and / or the optical functional surface(s) formed in the at least one optical pattern are established by any one of a low refractive index reflector, polarizer, diffuser, absorber, or any combination thereof.

10. The optical incoupling element according to any one of claims 1 to 9, wherein the at least one optical pattern is configured to perform at least one optical function by adjusting a number of parameters relating to the optical functional cavity or group of optical functional cavities within the at least one pattern, the number of parameters including individual parameters or any combination of parameters selected from the group consisting of dimensions, shape, cross-sectional profile, orientation, periodicity, and fill factor.

11. The optical incoupling element according to any one of claims 1 to 10, wherein the optical functional cavity is configured and arranged within the at least one optical pattern to form a plurality of periodic patterns having different periods.

12. The optical incoupling element according to any one of claims 1 to 11, wherein the optical functional cavity is configured and arranged within the at least one optical pattern to form a constant periodic pattern.

13. The optical incoupling element according to any one of claims 1 to 12, wherein the optical functional cavity in the at least one optical pattern is established by discrete or at least partially continuous pattern feature portions.

14. The optical incoupling element according to any one of claims 1 to 13, wherein the optical functional cavity is established by a two-dimensional or three-dimensional pattern feature portion having a cross-sectional profile selected from the group consisting of linear, rectangular, triangular, blazed, inclined, trapezoidal, curved, wavy, and sinusoidal profiles.

15. An optical incoupling element according to any one of claims 1 to 14, comprising at least two substrate components, wherein at least one cavity pattern is formed on a flat plane of one of the at least two substrate components, thereby establishing a substrate component having a patterned surface which is the flat plane on which the at least one cavity pattern is formed, and abutting the other substrate component of the at least two substrate components against an entirely flat surface, thereby forming the at least one optical pattern having the optical functional cavities alternating with flat bonding regions at the interface between the patterned surface and the entirely flat surface of the at least two substrate components.

16. The optical incoupling element according to any one of claims 1 to 15, wherein the substrate or the at least two substrate components having at least a patterned surface are formed of an optically transparent material.

17. The optical incoupling element according to claim 15 or 16, wherein the other substrate component having an overall flat surface is formed of any one of an optically transparent material, a colored material, a reflective material, and a combination thereof.

18. The optical incoupling element according to any one of claims 1 to 17, wherein the optical functional cavity is filled with a gaseous material.

19. The optical incoupling element according to any one of claims 1 to 18, wherein the optical functional cavity is composed of a certain number of cavity patterns arranged in a stacked configuration.

20. An optical incoupling element according to any one of claims 1 to 19, wherein it is provided with a light guide mounting surface, and the light guide mounting surface is an adhesive layer.

21. The optical incoupling element according to claim 20, wherein at least a portion of the outer surface located on the opposite side of the light guide mounting surface of the optical incoupling element is tapered with respect to a plane including the longitudinal direction of the light guide medium.

22. The optical incoupling element according to claim 21, wherein the three-dimensionally formed optical surface having at least one optionally selected pattern is arranged on a plane defined by the surface of the optical incoupling element located opposite the light guide mounting surface.

23. The optical incoupling element according to any one of claims 1 to 21, wherein the three-dimensionally formed optical surface having at least one optionally selected pattern is located on a plane defined by a surface in the optical incoupling element that is perpendicular to the plane including the longitudinal direction of the light guide medium and facing the emitter device.

24. An optical incoupling element according to any one of claims 1 to 23, comprising at least two adjacent functional zones independently configured to perform optical functions related to incoupling incident light and adjusting the direction of the incoupling light so that the incoupling light is directed (or redirected) toward the light guide medium.

25. The optical incoupling element according to claim 24, wherein the at least two adjacent functional zones are formed by separate element modules interconnected by an interface layer and optionally an adhesive.

26. An optical incoupling element according to any one of claims 1 to 25, provided in the form of an elongated strip.

27. An optical incoupling element according to any one of claims 1 to 26, further comprising a wavelength conversion layer.

28. An arrangement comprising at least two incoupling elements disposed on the light guide medium, wherein each element is an optical incoupling element according to any one of claims 1 to 27.

29. A method for manufacturing an optical incoupling element comprising a substrate, which is an independent optical functional member, and at least one three-dimensionally formed optical surface having at least one pattern formed on the substrate, To manufacture a master tool for at least one pattern by a manufacturing method selected from lithography, 3D printing, micromachining, laser engraving, or any combination thereof, Transferring the at least one pattern onto the substrate to generate the at least one three-dimensionally formed optical surface having a predetermined optical function, Includes, The at least one three-dimensionally formed optical surface comprises at least one optical pattern formed in the substrate and consisting of a plurality of periodic pattern feature portions configured as optical functional cavities. A method wherein the at least one three-dimensionally formed optical surface is configured to incouple incident light and generate incoupled light, and to adjust the direction of the incoupled light transmitted through an optical contact surface established at the interface between the substrate and the light guide medium, thereby causing the incoupled light to obtain a propagation path through the light guide medium via a series of internal total internal reflections, and the optical incoupling element is configured to receive light on the at least one pattern from a direction parallel to a plane including the longitudinal direction of the light guide medium, thereby causing all light emitted by the emitter device to be incident on the optical incoupling element and all light received by the incoupling element to be incoupled to the light guide medium.

30. The method according to claim 29, comprising generating a cavity pattern(s) by applying an additional substrate layer to the surface of a patterned element by a lamination method selected from roll-to-roll lamination, roll-to-sheet lamination, or sheet-to-sheet lamination.

31. The method according to claim 29 or 30, comprising a reproduction of the fabricated pattern, wherein the pattern reproduction method is selected from imprint, extrusion, or 3D printing.

32. A light guide comprising an optically transparent medium configured to establish a path for light propagation through the light guide medium, and at least one optical incoupling element according to any one of claims 1 to 27, wherein the at least one optical incoupling element is attachable to at least one plane of the light guide medium.

33. The light guide according to claim 32, wherein the at least one optical incoupling element is attached to the at least one plane of the light guide medium by adhesive.

34. Use of the light guide according to claim 32 or 33 in illumination and / or display.

35. An optical unit comprising at least one optical incoupling element having an adhesive layer for attaching a light guide, and at least one emitter device, wherein the at least one optical incoupling element is an optical incoupling element according to any one of claims 1 to 27.

36. The optical unit according to claim 35, wherein the at least one emitter device is at least partially integrated within the substrate material forming the optical incoupling element.

37. The optical unit according to claim 35 or 36, wherein the at least one emitter device is selected from the group consisting of light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), laser diodes, LED bars, OLED strips, microchip LED strips, and cold cathode tubes.

38. An optical unit according to any one of claims 35 to 37, referencing claim 27, comprising: at least one optical emitter device configured to emit monochromatic light; and the optical incoupling element including the wavelength conversion layer.

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