FI123032B - Process for making a light-conductor arrangement and light-conductor arrangement - Google Patents

Description

A method for making a light guide arrangement and a light guide arrangement

Background of the Invention

The present invention relates to a method for manufacturing a light guide arrangement, the method comprising: selecting a light guide comprising a first surface and a second surface, and an edge portion connecting said surfaces, forming a light transmission interruption point extending from the first surface to the second surface of the light guide; , forming a surface layer by adding a light-opaque material to the first and / or second surface at a position adjacent to the discontinuous point, superimposing the two light conductors so as to form a photoconductor stack, and arranging the discontinuous point of the first photoconduct

The invention further relates to a light guide arrangement comprising a light guide having a first surface and a second surface and an edge portion connecting said surfaces, comprising a discontinuity arranged to prevent light transmission and extending from a first surface to a second surface of a light guide at the va-20, the light guide is across a cutout having an opaque surface layer disposed on the first and / or second surface of the light guide, the light guide arrangement comprising a light guide stack having at least two light guide disposed in a discontinuous position on the first light guide. pages as the discontinuity of another photoconductor.

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ς Covers for electronic devices, especially portable electronic devices ^ such as mobile phones, communicators, handhelds,

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The structures of conventional computers, game consoles or controllers, audio and / or visual material reproducers, heart rate monitors, etc. typically comprise ir illuminated objects such as keyboards and / or dedicated keys or controls, displays, visual effects elements, etc. .

The light needed for illumination is produced by one or more light sources, most typically by an LED (Light Emitting Diode). The light is delivered from the light source to the object to be illuminated by a light guide.

35 This is made of a light transmitting polymeric material. Fiber optic arrays are increasingly being used in which the light conductor is a thin film-like 2 element having a thickness of up to about 0.5 mm, most often about 0.1 to 0.3 mm. The advantage of such a light guide is, among other things, that it has a small space requirement, which is a significant advantage in the pursuit of ever smaller structures and devices.

A problem with the known light-guide arrangement is that the light-guide also distributes light to parts of the device which are not intended to be illuminated. with light, or so-called. light leakage. The problem is exacerbated in devices where it is desired to implement demanding lighting arrangements, for example, to use multi-colored illumination in parallel so that different colors of light are not mixed together, or in which it is desired to accurately limit light to a particular part of the device.

BRIEF DESCRIPTION OF THE INVENTION It is an object of the present invention to provide a novel and improved method for manufacturing a photoconductor and an arrangement of a photoconductor which can limit the above problem.

The method of the invention is characterized in that each of the photoconductors has at least one discontinuity in the region of the periphery of the photoconductor and that these discontinuities are arranged in the region of the opposite edge portions of the photoconductor stack.

The optical fiber arrangement according to the invention is characterized in that the at least two photoconductors have at least one discontinuity in the region of the peripheral portion of the photoconductor in question, and that said discontinuity locations are arranged in the region of opposite edge portions of the photoconductor stack.

Other embodiments of the invention are characterized in what is set forth in the other claims. There are inventive embodiments

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^ also disclosed in the description and drawings of this application. The inventive content contained in the application may also be defined otherwise than in the claims below. The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of the stated or implicit subtasks or the benefits or classes of benefits achieved. In this case, some of the attributes contained in the claims below may be redundant for separate inventive ideas. Aspects of the various embodiments of the invention may be applied in conjunction with other embodiments within the scope of the inventive concept.

The idea of the invention is to provide a light conductor with a discontinuity point which prevents or at least restricts the passage of light. An advantage of the invention is that it can be implemented in very thin light conductors at low manufacturing costs.

The idea of an embodiment of the invention is to form a discontinuity point by making an incision in the light guide. The advantage is that the 5 incision is particularly advantageous to manufacture and that there is no need to remove waste from the manufacturing process.

Another idea of the invention is to form a discontinuity point by making a hole in the light guide. The advantage is that the hole is inexpensive to manufacture and that it prevents light propagation in the photoconductor quite effectively.

The idea of a third embodiment of the invention is to provide a discontinuity site by adding a masking agent to the peripheral portion of the light guide. The advantage is that the masking material can be quickly applied to the edge portion and that light transmission is substantially prevented and / or co-or partially reflected through the edge portion in an undesirable direction.

The idea of a fourth embodiment of the invention is to include a surface layer at the discontinuity site by adding a light-impermeable material to the first and / or second surface of the photoconductor at a point limited to the discontinuity. The advantage is that in a simple way, an increased light transmission reduction effect is obtained at the discontinuity point, especially for light propagating in the light guide with the greatest reflection angles.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the invention will be explained in more detail in the accompanying drawings, in which Fig. 1a is a schematic representation of a light guide according to the invention.

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Fig. 1b schematically shows a part according to Fig. 1a

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9 is a sectional view taken along line A-A, FIG. 1c schematically illustrates a light guide according to the invention. Fig. 1d is a schematic view of a light guide arrangement of Fig. 1c, cross-sectioned along line BB; Fig. 3a is a schematic view of a third optical fiber arrangement according to the invention in a perspective view; Fig. 5 is a schematic view in side and cross sectional view of a fifth light guide arrangement according to the invention, and Fig. 6 schematically shows a top view of a sixth optical fiber arrangement according to the invention.

In the figures, some embodiments of the invention are shown in simplified form for clarity. Like parts are denoted by like reference numerals in the figures.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1a is a schematic perspective view of a part of a photoconductor arrangement according to the invention, and Fig. 1b is a cross-sectional view taken along line A-A in Fig. 1a.

20 The light guide 1 is a so-called. a thin or film photoconductor, the first surface 2 of which is typically parallel to the second surface 3, i.e., the photoconductor 1 is typically of the same thickness throughout. The thickness of the light guide 1 is usually not more than about 0.5 mm, most often about 0.1 to 0.3 mm, but it can of course be greater.

The light guide surfaces 2, 3 each form a two-dimensional pin C 1 | ς nan that is either planar or bent in one, two or three orthogonal space planes. The shape of the surface 2, 3 of the light guide 1 may be pre-9, e.g., convex, concave, saddle surface, spherical, conical or cylindrical surface or part thereof

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o etc.

30 Photoconductor 1 is made in a manner known per se and from known materials, so these matters are not discussed in this specification in its min. It should be noted, however, that the light guide 1 not only conducts light from the light source o to the object to be illuminated, but also increasingly produces the final light effect.

For this purpose, structures and / or shapes which give rise to visible shapes, symbols, color fields, or the like, can be formed in the light guide 1 in a manner known per se, when a certain amount of light is introduced into the light guide in a specific manner. The light-off structures are typically part of the light guide 1, most often a shaped or painted interface of the light guide. Such light effects may be either stable or variable.

The light guide 1 shown in Fig. 1a has a basic rectangular shape: the shape of the light guide is chosen according to its intended use, so that its shape may differ greatly from that shown herein.

In the immediate vicinity of the light guide 1, light sources are provided which are surface mounted LEDs 8a, 8b in the present embodiment of the invention. Such so-called. side-firing LEDs and their attachment to the 10 circuits are known per se, and are not described in further detail herein. The light produced by the LEDs is directed towards the edge portion 4a, 4b of the light guide 1. The light source and the light guide may be in contact with one another, or there may be an air gap between them.

It should be noted that the light source may be other than the LED as any other known light source, such as a filament bulb, electroluminescent lamp, laser or the like.

The term "light" as used herein refers not only to the wavelength of visible light but also to the ultraviolet or infrared wavelength.

All LEDs 8a, 8b may emit light over the same wavelength range, or alternatively, there may be differences between the wavelength ranges of LEDs 8a, 8b. The LEDs 8a, 8b can be operated in a manner known per se, for example, all at once or even by turning them on or off one by one. The luminous efficacy of the LEDs 8a, 8b can also be adjusted.

Figure 1b shows how the light L, L 'emitted by the LEDs 8a, 8b meets the light guide 1. In the figure, the light emitted from the right, i.e. the light L' emitted by the right-hand LEDs 8b, penetrates unobstructed into the light guide 1.

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£ from edge portion 4b and proceeds as light LG 'to exit light guide 1 as light W

° through first surface 2. The first surface 2 acts in a so-called as a light-emitting surface through which most of the light introduced into the photoconductor 1 is removed. The structures and shapes possibly formed in the light guide 1 for this purpose then create a visual effect. It may, of course, be so that the light W emitted by the light guide is a substantially uniform illuminating field. The second surface 3 is the main outward surface arranged to substantially alter the direction of light LG 'so that it is directed to the first surface 2 passing through it as light W.

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Also, light is emitted through the second surface 3, but less than through the first surface 2. The propagation of light exiting through the second surface 3 may be stopped by an absorbent surface or reflecting surface arranged under the light guide. The reflective surface reflects light back through the light guide and further away from the light guide.

In the figure, the light L, i.e. the light L emitted by the left-hand LEDs 8a, also penetrates into the photoconductor but cannot pass through the photoconductor so that it can exit through the light-emitting surface from the photoconductor 1. This is extending from the first surface 2 of the photoconductor 1 to the second surface 3 of the photoconductor 1. The discontinuity site 5 forms a light-absorbing and / or reflective structure which prevents light from reaching certain portions of the photoconductor.

Now, the discontinuity site comprises two slits 6a, 6b at which the light guide 1 is crossed. The slits 6a, 6b are arranged parallel to each other at a suitable distance from the respective edge portion 4a and substantially parallel to said edge portion 4a. Between the incisions 6a, 6b is a short material cap 21 which increases the stiffness of the edge of the light guide. Preferably, the base is so short that it does not substantially affect the operation of the discontinuity site 5 as a light-transmitting structure 20. The discontinuity point 5 is substantially the entire length of the side of the photoconductor, but this is by no means necessary.

The incision 6a, 6b is made by cutting the light guide 1 with a sharp object such as a blade or laser, cutting, stamping or the like.

25 When making the incision, no or at least no significant amount of material is removed from the photoconductor 1, but only the light is cut off.

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the material of the material layer forming the conductor 1 over a given length.

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^ The light guide surfaces, incision surfaces, ° on either side of the incision 6a, 6b are extremely close to each other, but not in optical contact

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° 30 to each other.

| In connection with the incisions 6a, 6b, a light-impervious surface layer 7 extending over a distance is disposed on the first and second surfaces 2, 3 ^

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from the mold 6a, 6b both in the direction of the peripheral part 4a and in the opposite direction.

The topsheet 7 may be, for example, conventional dye, masking tape, printing ink, paint, etc. used in tampon printing. In one embodiment, an absorbent black color is used which effectively prevents 7 reflections. In another embodiment, a white color is used which acts as a light reflecting element.

The topsheet 7 may be formed, for example, by a tampon printing process, a screen printing process, an ink-jet process, or the like, which is known to you for coating and / or coating.

The width of the surface layer 7 may be substantially constant and conform to the edge of the light guide as in the pattern, or may vary in width to the extent that it forms patterns on the surface of the light guide. It should be noted, however, that the surface layers 7 are not necessary, so that one or both of them 10 may be omitted in some embodiments of the invention.

The discontinuity 5 prevents the light L emitted by the left-aligned LEDs 8a from reaching the further light guide 1. The appearance of the visual effects created by the light guide 1 is thus not dependent on the operation of the LEDs 8a on the left side of the light guide 1.

The number and length of the incisions 6a, 6b may be selected as required. The incisions do not have to be arranged one after the other in the same line, but they can be, for example, partially interlaced. The incisions can also be fitted to the center of the photoconductor, for example the center of the photoconductor.

Fig. 1c is a schematic perspective view of a photoconductor arrangement according to the invention, and Fig. 1d is a sectional view taken along line B-B in Fig. 1c.

The light guide arrangement comprises the light guide 1 shown in Figures 1a and 1b, which in this embodiment is referred to as the first light guide, and in addition the second light guide 9. The light guide 1, 9 are superimposed so that the second light guide 9 is under the first light guide 1. Thus formed is a stack of light guide 11 comprising two light conductors.

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In the figure, the discontinuous point of the first light guide 1 is denoted by ^ reference numeral 5a. The second light guide 9 comprises a discontinuity point 5b which in this embodiment is similar to the one described in the previous figures | first light guide discontinuity 5a. Thus, the discontinuous point 5b of the second light guide includes incisions 6c, 6d and surface layers 7.

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The discontinuous point 5b of the second photoconductor 9 is arranged at a different position o on the side of the photoconductor stack 11 than the discontinuous point 5a of the first photoconductor.

In this case, the discontinuous point 5b of the second photoconductor 9 is disposed on the opposite side of the photoconductor stack 11 relative to the discontinuous point 5a of the first photoconductor 1.

In Figure 1c, the light L produced by the LEDs 8a to the left of the photoconductor stack 11 penetrates into the first photoconductor 1 and 5 further as light W.

Due to the discontinuity of the second photoconductor 5b, the light of the said left-hand LEDs 8a is at least not substantially accessible to the second photoconductor 9.

Correspondingly, the light produced by the LEDs 8 8b positioned on the right side of the photoconductor stack 11 is transmitted to the second photoconductor 9 but not to the first photoconductor 1 due to its discontinuity 5a.

The light propagates in the second light guide 9 in a manner known per se and exits from it as light W '. Light W 'propagates through the first light guide 1 to be seen on the upper surface 17 of the light guide stack 11.

The light visible on the upper surface 17 of the photoconductor stack 11 may be from only the first photoconductor 1, only the second photoconductor 9, or both of the photoconductors 1.9. To display only light from the first light guide 1, the right LEDs 8b are turned off. If only light from the second light guide 1 is to be displayed, the left LEDs 8a are respectively deactivated. In the event that it is desired to display light from both the first and second photoconductors 1, 9, the photoconductors 1, 9 are illuminated by both the left and right LEDs. Thus, a variety of visual effects can be produced on the upper surface 17 of the photoconductor stack 11.

The left-hand LEDs 8a may differ from the right-hand LEDs 8b. The wavelength range o of the light emitted by the left-hand LEDs 8a may be different from that of the right-hand LEDs 8b.

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The light guides 1, 9 can be made of the same material. Of course, there may be differences in the materials of manufacture which change the color, refractive index or other optical property of the photoconductor. The light guide 1, 9 may comprise several layers of material. Light W may be the same or different color as tj · light W '. It is also possible to provide both left-hand and right-hand LEDs 8a, 8b to illuminate the optical fiber stack 11 simultaneously, whereby the νβ-ο light effect consists of a combination of the lights W, W '.

The photoconductor stack 11 may be provided with three, four or more photoconductors superimposed.

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The light guides 1, 9 are preferably attached to each other, for example, in the region of at least one of the edge portions or in substantially the entire contact area. The attachment may be effected, for example, by gluing, welding and / or in any other manner known per se.

The light conductors 1, 9 shown in Figure 1c are substantially the same. Such a photoconductor stack 11 may be shaped before or after the photoconductors have been superimposed. The design can be done in a manner known per se, for example by cutting or stamping. The photoconductors in the photoconductor stack 11 may also be of substantially different shapes.

Fig. 2a is a schematic perspective view of another optical fiber arrangement according to the invention, and Fig. 2b is a sectional view taken along the line C-C in Fig. 2a.

The discontinuity site 5 in this embodiment comprises a covering layer 12 of material 12 disposed on the edge portion 4a of the light guide. The masking layer 12 forms a layer impermeable to, or at least substantially impermeable to, the light wavelength L 'emitted by the LEDs 8a, which obstructs the said beam. light penetration into the photoconductor 1. The coating layer 12 may be formed of the same materials as those already mentioned as the material 20 of the surface layer 7.

Preferably, the material is, but is not necessarily, the same material as the topsheet 7 and is manufactured at the same time.

The covering layer 12 can be formed, for example, by a tampon printing method, a screen printing process, an ink-jet method, etc. 25 known methods.

Fig. 3a is a schematic perspective view of a third optical fiber arrangement according to the invention and Fig. 3b is a cross-sectional view.

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3a along line D-D of Figure 3a.

The light guide 1 comprises a discontinuity point 5 disposed on one edge portion 4a comprising an incision 6, a surface layer 7 and a covering layer 12. That is, the discontinuity point 5 comprises the essential features of the discontinuity points 5 shown in Figs. This achieves particularly good light coverage and / or shading properties.

In this context, it should be noted that the photoconductors comprising the discontinuous points 5 described in this specification may be joined together to form a photoconductor stack 11. The photoconductors in the photoconductor stack may thus differ from each other in terms of location, structure, dimensioning and the like.

Figure 4a is a schematic perspective view of a fourth optical fiber arrangement according to the invention and Figure 4b is a sectional view taken along line E-E of Figure 4a.

The discontinuous point of the photoconductor 1 is substantially the same as that of the photoconductor shown in Fig. 3a, except that the discontinuous point 5 now comprises only the surface layers 7 and the covering layer 12 and not the incision at all.

Fig. 5 schematically shows a side view and a cross-section of a fifth optical fiber arrangement according to the invention. The discontinuity point 5 comprises a hole 13 extending from the upper surface 17 to the lower surface of the photoconductor. The hole 13 differs from the above incision in that the opposed surfaces of the photoconductor are not attached to each other in the hole.

The hole 13 may be formed, for example, by removing material from the photoconductor, for example, by cutting, drilling or punching with a blade or laser.

The hole 13 may be a cylindrical or polygonal cylindrical cross-section, or a hole extending elongated to the light guide surface 2 and having the same width 20 or the width may vary in the longitudinal direction of the hole. The elongated hole may be straight or curved in one or more directions or the like.

The hole 13 is arranged away from the edge portions 4 of the light guide so that it divides the light guide 1 into two equal parts. The left side of the light guide may be illuminated in a different way than the right side. Covering layers 12 are provided on the walls 22 of the hole 13, which, however, are not always necessary. 5 It should be noted in this connection that instead of hole 13, one could

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use the incision shown in the previous figures, and that the incisions shown in the previous figures could be replaced by a hole 13. As with the incisions 6a, 6b, the number and length of the holes 30 in the direction of surfaces 2, 3 can be selected according to g.

^ The advantage of hole 13 over incision is, among other things, that the hole

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Due to the wider air gap 13, the propagation of light is more effectively prevented and coating layers can be produced on the surface of the hole to complement the anti-propagation effect. The incision, on the other hand, is easier to make and thus cheaper.

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On the first surface 2 of the photoconductor, on both sides of the hole 13, surface layers 7 are preferably formed which coincide with the coating layer 12. The surface layers 7 are preferably of the same material as the coating layer 12. The surface layers may also be made on the lower surface 5 of the photoconductor.

Fig. 6 schematically shows a top view of a sixth optical fiber arrangement according to the invention. The light guide arrangement comprises a light guide stack 11 for illuminating the keypad of a mobile phone.

The upper light guide 1 is divided by three discontinuities into three light areas. The first illumination area 14 is arranged to illuminate a so-called illumination area. navigation key 18 and its surroundings. The first illumination area 14 is illuminated by the first LED 8a.

The second illumination area 15 is arranged to illuminate keys adjacent to the navigation key, such as the call answer key 19 and the call termination key 20. The keys 19, 20 are provided with different colored light discontinuity, or using different colored light masks on the keys. The second illumination area 15 is illuminated by the second LED 8b.

The second illumination area 15 is separated from the first illumination area 14 by a first discontinuity point 5a. This comprises three slits 6a arranged to surround the first illuminating area 14. The first discontinuity 5a also includes a surface layer 7a arranged on the upper surface of the light guide.

The third illumination area 16 is separated from the second illumination area 15 by a second discontinuity 5b. This is an area extending substantially directly across the entire light guide, including three incisions 6b and a surface layer 7b. Third

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The illumination area 16 is adapted to illuminate the number keys 19.

° Note in this connection that some of the incisions 6a to 6b or ° 30 may all be replaced by holes 13, and that the structure of the discontinuities 5a and | in general, the composition may be selected in the ways mentioned in the preceding figures.

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The number keys 19 can be illuminated in two different ways so that they display either the numbers - as now shown in Figure 6 - or, for example, the characters of the ^ 35 Western writing system. Of course, characters from other writing systems and other characters, symbols, informative or purely decorative effects, etc. can be represented.

The light guide 1 is part of the light guide stack 11 including a second light guide 9. The second light guide 9 is arranged under the first light guide 1. The user of the Mat-5 handset can choose whether to display numbers or Western characters. For example, if the selection targets the characters that appear when the first light guide 1 is illuminated, the mobile phone control system turns on the LEDs illuminating the third light region 16 of the first light guide 1. At the same time, the control system switches off the LEDs 10 arranged to illuminate the second light guide 9.

In some cases, the features set forth in this application may be used as such, despite other features. On the other hand, the features disclosed in this application may be combined, if necessary, to form different combinations.

Here are some other embodiments of the invention in free order:

The discontinuity is formed by making an incision in the light guide, for example at a distance from the edge portion and at least substantially parallel to said edge portion.

The discontinuity is formed by making a hole in the photoconductor, preferably a hole which is elongated in the direction of the surface of the photoconductor.

A discontinuity site is formed substantially perpendicular to the first and second surfaces of en-25.

A discontinuity is formed by adding a masking agent to the peripheral portion of the light guide 5.

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A discontinuity is formed by adding a masking agent to the wall of the hole formed in the photoconductor.

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° 30 A surface is formed by the addition of a light - impermeable material a first and / or a second surface at a position adjacent to the discontinuity site.

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Arranging two light conductors on top of each other to form a light-g conductor stack, and arranging a first photoconductor discontinuity on a different side of the photoconductor stack than the second photoconductor discontinuity, e.g. on opposite sides.

Attach the photoconductors in the photoconductor stack to each other.

The discontinuity is an incision at which the light guide is crossed, the incision being preferably arranged at a distance from the peripheral portion and at least substantially parallel to said edge.

The discontinuity point is a hole, preferably a hole which is elongated in the direction of the surface of the light guide.

The discontinuity is a layer of masking material disposed on the peripheral portion of the photoconductor, such as the wall of the hole formed in the photoconductor.

A light-impermeable surface layer disposed on the first and / or second surface of the photoconductor is arranged in connection with the discontinuity point.

The photoconductor arrangement comprises a photoconductor stack having at least two photoconductors disposed on one another and the discontinuous point of the first photoconductor being disposed at a different position on the side of the photoconductor stack than the discontinuous point of the second photoconductor.

At least two photoconductors have at least one discontinuity in the region of the peripheral portion of the photoconductor in question, and that said discontinuity points are disposed on opposite sides of the photoconductor stack.

20 The light guide arrangement is adapted to illuminate the keyboard of the portable electronic device.

The light guide arrangement is adapted to illuminate the decoration elements of the electronic device.

The drawings and the description related thereto are only intended to illustrate the idea of the invention. It will be apparent to one skilled in the art that the invention is not limited to the embodiments described above, in which the invention is described by way of example only, but many modifications and various embodiments of the invention

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are within the scope of the inventive idea defined in the claims below.

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Claims (8)

A method of producing a light guide arrangement (1, 9), in which method: a light guide (1, 9) comprising a first surface (2) and a second surface (3) is selected, and an edge portion (4a, 4b, 4c, 4d) joining the surfaces in question, a discontinuity site (5, 5a, 5b) is formed which prevents the transmission of light to the light guide (1, 9) and extending from the first surface (2) to the second surface (3), the discontinuity site (5, 5a, 5b) is formed by making a cut (6a, 6b, 6c, 6d) in the light guide (1,9), a surface layer (7) is formed by adding a light transmissible part on the first and / or second surface (2, 3) of a site confined to the discontinuity site (5, 5a, 5b), two light conductors (1, 9) are arranged on each other so as to form a light-conductor stack (11), and the first light conductor (1) discontinuity site is arranged at a different location of the light conductor stack than the second light conductor (9) discontinuity site, characterized in that in each light conductor (1, 9) there is at least one discontinuity site (5, 5a, 5b) in the region of the edge part of the light conductor (4a, 4b, 4c, 4d) and that the discontinuity points in question are arranged in the area of the light conductor stack ( 11) opposing edge portions (4a, 4b, 4c, 4d). Method according to claim 1, characterized in that the section (6a, 6b, 6c, 6d) is made at a distance from the edge part (4a, 4b, 4c, 4d) and at least substantially parallel to the edge part (4a, 4b, 4c). , 4d) in question. C \ l o 3. A method according to any of the preceding claims, characterized in that the discontinuity point (5, 5a, 5b) is formed substantially vertically 0 in relation to the first and second surfaces (2, 3). ° 30 A method according to any of the preceding claims, characterized in that the light guides (1,9) are attached to each other. CM CD 05 § 5. Light conductor arrangement, comprising a light conductor (1, 9) with a first surface (2) of CM and a second surface (3) and an edge part (4a, 4b, 4c, 4d) which joins the surfaces in question, which arrangement comprises a discontinuity site (5, 5a, 5b) arranged to prevent the transmission of light and extending from the first surface (2) of the light guide to the second surface (3), said discontinuity site being a section (6a, 6b, 6c); 6d), wherein the light guide (1, 9) is off, in connection with which a cut (6a, 6b, 6c, 6d) is provided with a light-impervious surface layer (7) arranged on the first and / or second surface of the light guide ( 2, 3), said light-conductor arrangement comprising a light-conductor stack (11) having at least two light-conductors (1, 9) arranged on each other, that the first light-conductor discontinuity site is arranged at a different location of the light-conductor stack side than the second light-conductor discontinuous site, 10 at least two light conductors (1.9) there is at least one discontinuity site in the region of the edge portion of the light guide in question, and the discontinuity points in question are arranged in the area of the opposing edge portions (4a, 4b, 4c, 4d) of the light guide stack (11). 15 Light-conductor arrangement according to claim 5, characterized in that a section (6a, 6b, 6c, 6d) is arranged at a distance from the edge part and at least substantially parallel to the edge in question. 7. Light conductor arrangement according to any of claims 5-6, characterized in that it is arranged to illuminate the keyboard of a portable electronic device. 8. Light conductor arrangement according to any of claims 5-6, characterized in that it is arranged to illuminate the decoration element of the electronic device. CM δ CM CD o CD o X tr CL CD CM CD 05 O O CM