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Title:
FRAME FOR A TOUCH-SENSITIVE DEVICE AND TOOL THEREFOR
Document Type and Number:
WIPO Patent Application WO/2020/080992
Kind Code:
A1
Abstract:
An elongate frame for a touch-sensitive device comprises: a bottom wall, a top wall and a side wall connected therebetween. The elongate frame also comprises a first mounting and a second mounting for respectively fixing at least one light emitter and a touch surface with respect to the frame. The elongate frame also comprises a slot at least partially positioned above the second mounting and the first mounting wherein the slot is arranged to receive an optical component.

Inventors:
SVENSSON PATRIK (SE)
WIESEL TOBIAS (SE)
WESTLUND JOHAN (SE)
BERGSTRÖM HÅKAN (SE)
Application Number:
PCT/SE2019/050953
Publication Date:
April 23, 2020
Filing Date:
October 02, 2019
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
FLATFROG LAB AB (SE)
International Classes:
G06F1/16; G02B5/02; G06F3/042
Domestic Patent References:
WO2018182476A12018-10-04
WO2017138863A12017-08-17
WO2018106176A12018-06-14
WO2013138003A12013-09-19
WO2013081818A12013-06-06
Foreign References:
US20110210946A12011-09-01
Attorney, Agent or Firm:
PATIO AB (SE)
Download PDF:
Claims:
Claims

1. An elongate frame for a touch-sensitive device comprising:

a bottom wall, a top wall and a side wall connected therebetween;

a first mounting and a second mounting for respectively fixing at least one light emitter and a touch surface with respect to the frame; and

a slot at least partially positioned above the second mounting and the first mounting wherein the slot is arranged to receive an optical component.

2. An elongate frame according to claim 1 wherein the optical component is a light diffuser.

3. An elongate frame according to claims 1 or 2 wherein the slot is angled with respect to the side wall and the top wall such that light emitted from the emitter is diffused above the touch surface when incident on the optical component.

4. An elongate frame according to claims 1 to 3 wherein the slot is angled with respect to the plane of the touch surface when mounted in the second mounting.

5. An elongate frame according to any of the preceding claims wherein the slot comprises a first lip and a second lip arranged to retain the edges of the optical component.

6. An elongate frame according to claim 5 wherein the slot comprises a ridge for urging the optical component against the first and second lips.

7. An elongate frame according to any of the preceding claims wherein the optical component comprises an elongate planar shape.

8. An elongate frame according to any of the preceding claims wherein the optical component is a light diffusing film.

9. A touch-sensitive device comprising:

a touch surface;

at least one light emitter;

a frame according to claims 1 to 8; and

an optical component mounted in the slot.

10. An optical component application tool for an elongate frame of touch- sensitive device wherein the elongate frame comprises a slot arranged to receive an optical component, the optical component application tool comprising:

at least one reference surface engageable with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and

an optical component feeder aligned with respect to the at least one reference surface wherein the optical component feeder is arranged to feed the optical component into the slot.

1 1 . An optical component application tool according to claim 10 wherein the tool comprises a feeding surface engageable with the optical component and the feeding surface is alignable with the slot when the elongate frame is engaged with the at least one reference surface.

12. An optical component application tool according to claims 10 or 1 1 wherein the optical component pushes the optical component into the slot.

13. An optical component application tool according to claims 10 to 12 wherein the optical component feeder comprises at least one roller engageable with the optical component.

14. An optical component application tool according to claim 13 wherein the optical component is positioned between at least one roller and the feeding surface.

15. An optical component application tool according to claims 13 or 14 wherein the at least one roller comprises two rollers and the optical component is feedable between the two rollers.

16. An optical component application tool according to claims 10 to 15 wherein the optical component feeder pulls the optical component into the slot.

17. An optical component application tool according to claim 16 wherein the optical component feeder is fixed to the optical component.

18. An optical component application tool according to claims 10 to 17 wherein the optical component application tool is moveable along a longitudinal axis of the elongate frame.

19. An optical component application tool according to claim 18 comprising at least one coupling to prevent relative movement of the optical component application tool in a plane perpendicular to the longitudinal axis of the elongate frame.

20. An optical component application tool according to claim 18 wherein the at least one coupling comprises an interior coupling portion having a reciprocal shape to a cross-sectional shape of the elongate frame.

21 . An optical component application tool wherein the optical component is a light diffuser.

22. A method of applying an optical component to an elongate frame of touch-sensitive device wherein the elongate frame comprises a slot arranged to receive the optical component comprising:

engaging at least one reference surface with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and

feeding the optical component into the slot with an optical component feeder aligned with respect to the at least one reference surface. 23 A method according to claim 22 wherein the optical component is a light diffuser.

AMENDED CLAIMS

received by the International Bureau on 04 December 2019 (04.12.2019)

[Claim 1] An elongate frame for a touch-sensitive device comprising:

a bottom wall, a top wall and a side wall connected therebetween; a first mounting and a second mounting for respectively fixing at least one light emitter and a touch surface with respect to the frame; and a slot at least partially positioned above the second mounting and the first mounting wherein the slot is arranged to receive an optical component,

wherein the slot is angled with respect to the side wall and the top wall such that light emitted from the emitter is diffused above the touch surface when incident on the optical component.

[Claim 2] An elongate frame according to claim 1 wherein the optical component is a light diffuser.

[Claim 3] An elongate frame according to claims 1 to 2 wherein the slot is angled with respect to the plane of the touch surface when mounted in the second mounting.

[Claim 4] An elongate frame according to any of the preceding claims wherein the slot comprises a first lip and a second lip arranged to retain the edges of the optical component.

[Claim 5] An elongate frame according to claim 4 wherein the slot comprises a ridge for urging the optical component against the first and second lips. [Claim 6] An elongate frame according to any of the preceding claims wherein the optical component comprises an elongate planar shape.

[Claim 7] An elongate frame according to any of the preceding claims wherein the optical component is a light diffusing film.

[Claim 8] A touch-sensitive device comprising:

a touch surface;

at least one light emitter;

a frame according to any one of claims 1 to 7 ; and an optical component mounted in the slot.

[Claim 9] An optical component application tool for an elongate frame of touch- sensitive device wherein the elongate frame comprises a slot arranged to receive an optical component, the optical component application tool comprising:

at least one reference surface engageable with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and an optical component feeder aligned with respect to the at least one reference surface wherein the optical component feeder is arranged to feed the optical component into the slot,

wherein the optical component feeder comprises at least one roller en- gageable with the optical component.

[Claim 10] An optical component application tool according to claim 9 wherein the tool comprises a feeding surface engageable with the optical component and the feeding surface is alignable with the slot when the elongate frame is engaged with the at least one reference surface.

[Claim 11] An optical component application tool according to claims 9 or 10 wherein the optical component pushes the optical component into the slot.

[Claim 12] An optical component application tool according to any of claims 9 to

11 wherein the optical component is positioned between at least one roller and the feeding surface.

[Claim 13] An optical component application tool according to claims 11 or 12 wherein the at least one roller comprises two rollers and the optical component is feedable between the two rollers.

[Claim 14] An optical component application tool according to any of claims 9 to

13 wherein the optical component feeder pulls the optical component into the slot.

[Claim 15] An optical component application tool according to claim 14 wherein the optical component feeder is fixed to the optical component.

[Claim 16] An optical component application tool according to any of claims 9 to

15 wherein the optical component application tool is moveable along a longitudinal axis of the elongate frame.

[Claim 17] An optical component application tool according to claim 16

comprising at least one coupling to prevent relative movement of the optical component application tool in a plane perpendicular to the lon gitudinal axis of the elongate frame.

[Claim 18] An optical component application tool according to claim 16 wherein the at least one coupling comprises an interior coupling portion having a reciprocal shape to a cross-sectional shape of the elongate frame.

[Claim 19] An optical component application tool wherein the optical component is a light diffuser.

[Claim 20] A method of applying an optical component to an elongate frame of touch-sensitive device wherein the elongate frame comprises a slot arranged to receive the optical component comprising: engaging at least one reference surface with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and feeding the optical component into the slot with an optical component feeder aligned with respect to the at least one reference surface.

[Claim 21] A method according to claim 20 wherein the optical component is a light diffuser.

Description:
Frame for a touch-sensitive device and tool therefor

The present invention relates to a frame for a touch-sensitive device and tool therefor.

Touch-sensitive systems ("touch systems") are in widespread use in a variety of applications. Typically, the touch systems are configured to detect a touching object such as a finger or stylus, either in direct contact, or through proximity (i.e. without contact), with a touch surface. Touch systems may be used as touch pads in laptop computers, equipment control panels, and as overlays on displays e.g. hand-held devices, such as mobile telephones. A touch panel that is overlaid on or integrated in a display is also denoted a "touch screen". Many other applications are known in the art.

There are numerous known techniques for providing touch sensitivity, e.g. by incorporating resistive wire grids, capacitive sensors, strain gauges, etc. into a touch panel. There are also various types of optical touch systems, which e.g. detect attenuation of emitted light by touch objects on or proximal to a touch surface.

A known touch-sensitive apparatus is an‘above surface optical touch system’, with a set of optical emitters are arranged around the periphery of a touch surface to emit light that travels above the touch surface. A set of light detectors are also arranged around the periphery of the touch surface to receive light from the set of emitters from above the touch surface. An object that touches the touch surface will attenuate the light on one or more propagation paths of the light and cause a change in the light received by one or more of the detectors. The location (coordinates), shape or area of the object may be determined by analysing the received light at the detectors. Examples of such touch systems are found in e.g. PCT/SE2017/051233 and PCT/EP2018/052757.

One component of the touch-sensitive device is a diffuser for propagating the light over the touch surface correctly. The diffuser can be an elongate piece of plastic with a surface having light diffusive properties angled to diffuse the emitted light over the touch surface. The diffuser is clipped or glued into the frame of the touch-sensitive device.

A problem with the diffuser component is that it is relatively expensive to manufacture and install. Furthermore, the diffuser must be located above the touch surface to guide and diffuse the light above the touch surface. This means that the size of the diffuser affects the size of the bezel at the end of the touch- sensitive apparatus.

In a first aspect of the invention there is provided an elongate frame for a touch- sensitive device comprising: a bottom wall, a top wall and a side wall connected therebetween; a first mounting and a second mounting for respectively fixing at least one light emitter and a touch surface with respect to the frame; and a slot at least partially positioned above the second mounting and the first mounting wherein the slot is arranged to receive an optical component.

Optionally, the optical component is a light diffuser.

Optionally, the slot is angled with respect to the side wall and the top wall such that light emitted from the emitter is diffused above the touch surface when incident on the optical component.

Optionally, the slot is angled with respect to the plane of the touch surface when mounted in the second mounting.

Optionally, the slot comprises a first lip and a second lip arranged to retain the edges of the optical component.

Optionally, the slot comprises a ridge for urging the optical component against the first and second lips. Optionally, the ridge pushes against the optical component to deform the optical component. Optionally, the ridge pushes against the optical component to cause the optical component to have a convex cross-sectional shape. Optionally, the optical component comprises an elongate planar shape.

Optionally, the optical component is a light diffusing film.

In a second aspect of the invention, there is provided a touch-sensitive device comprising: a touch surface; at least one light emitter; a frame according to the first aspect; and an optical component mounted in the slot.

In a third aspect of the invention there is provided an optical component application tool for an elongate frame of touch-sensitive device wherein the elongate frame comprises a slot arranged to receive an optical component, the optical component application tool comprising: at least one reference surface engageable with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and an optical component feeder aligned with respect to the at least one reference surface wherein the optical component feeder is arranged to feed the optical component into the slot.

Optionally, the tool comprises a feeding surface engageable with the optical component and the feeding surface is alignable with the slot when the elongate frame is engaged with the at least one reference surface.

Optionally, the optical component feeder pushes the optical component into the slot.

Optionally, the optical component feeder comprises at least one roller engageable with the optical component.

Optionally, the optical component is positioned between at least one roller and the feeding surface.

Optionally, the at least one roller comprises two rollers and the optical component is feedable between the two rollers. Optionally, the optical component feeder pulls the optical component into the slot.

Optionally, the optical component feeder is fixed to the optical component.

Optionally, the optical component application tool is moveable along a longitudinal axis of the elongate frame.

Optionally, at least one coupling prevents relative movement of the optical component application tool in a plane perpendicular to the longitudinal axis of the elongate frame.

Optionally, the at least one coupling comprises an interior coupling portion having a reciprocal shape to a cross-sectional shape of the elongate frame.

In a fourth aspect of the invention there is provide a method of applying an optical component to an elongate frame of touch-sensitive device wherein the elongate frame comprises a slot arranged to receive the optical component comprising: engaging at least one reference surface with at least a portion of the elongate frame such the slot is located in a predetermined position with respect to the at least one reference surface; and feeding the optical component into the slot with an optical component feeder aligned with respect to the at least one reference surface.

Embodiments of the present invention aim to address the aforementioned problems.

Various other aspects and further embodiments are also described in the following detailed description and in the attached claims with reference to the accompanying drawings, in which:

Figure 1 shows a cross-sectional side view of an embodiment of a touch- sensitive device; Figure 2 shows a close-up cross-sectional side view of an embodiment of a touch-sensitive device;

Figure 3 shows a perspective view of an embodiment of an elongate frame; Figure 4 shows a perspective view of a tool according to an embodiment; Figure 5 shows a perspective view of an embodiment an elongate frame engaged with a tool;

Figure 6 shows a perspective view of an embodiment an elongate frame engaged with a tool;

Figure 7 show a cross-sectional side view of an embodiment of the elongate frame and tool;

Figure 8 shows a perspective view of an embodiment of the elongate frame and tool; and

Figure 9 shows a close-up cross-sectional side view of an embodiment of a touch-sensitive device.

Figure 1 shows a cross-sectional side view of a touch-sensitive device 100 comprising an elongate frame 102. The elongate frame 102 extends around the periphery of the touch-sensitive device 100. The elongate frame 102 extends along a longitudinal axis B-B which extends into the page as shown in Figure 1 . A portion of the elongate frame 102 extending along the longitudinal axis B- B is shown in Figure 3. Figure 3 shows a perspective view of a portion of the elongate frame 102.

The elongate frame 102 comprises a top wall 104, a bottom wall 106 and a side wall 108 connected therebetween. The elongate frame 102 can comprises a plurality of surfaces defining voids for securing internal components. Indeed, the elongate frame 102 can comprise any suitable cross-sectional shape to accommodate different components and geometries. For example, the top wall 104, the bottom wall 106 and the side wall 108 can comprises multiple exterior surfaces 1 10. For the purposes of clarity only one of the multiple exterior surfaces 1 10 has been labelled. Each of the top wall 102, the side wall 108 and the bottom wall 106 and can comprise multiple interior and exterior surfaces. Figure 1 shows a cross-sectional side view through part of the periphery of the touch-sensitive device 100. For the purposes of clarity, not all the components and structure of the touch-sensitive device 100 are shown.

A light emitter component 1 12 is mounted on a substrate 1 14 such as a printed circuit board (PCB). For the purposes of clarity, a reciprocal light detector is not shown. However, the reciprocal light detector component is mounted on the substrate 1 14 adjacent to the light emitter component 1 12. As mentioned previously, the light emitter and light detector components are arranged on the substrate 1 14 along the periphery of the touch-sensitive device.

The substrate 1 14 is secured to the frame 102 by a first mounting 1 16. In some embodiments, the first mounting comprises at least one substrate mounting slot 1 16. The substrate mounting slot 116 is for receiving an edge of the substrate 1 14. In this way, the substrate 1 14 is slid into the substrate mounting slot 116 and the substrate 114 is held in place substrate mounting slot 1 16. In other embodiments, the first mounting 1 16 can be screws, glue, or any other suitable fixture for securing the substrate 1 14 to the frame 102. The substrate 1 14 is mounted in the frame 102 so that it extends in a plane which is substantially perpendicular to a touch surface 118. In this way, the touch surface 1 18 extends in a horizontal plane and the substrate 114 extends in a direction between the top wall 104 and the bottom wall 106. In alternative embodiments, (not shown), the substrate 1 14 can extend in a plane which is substantially parallel to the plane of the touch surface 1 18.

The touch surface 1 18 is mounted above the substrate 1 14 or adjacent to the substrate 1 14. The touch surface 1 18 in some embodiments is mounted to the elongate frame 102 in a second mounting 120 in the frame 102. The second mounting 120 as shown in Figure 1 is a pair of perpendicular surfaces against which the touch surface 118 abuts.

Alternatively, or additionally, the second mounting 120 is a peripheral touch surface mounting slot (not shown) for receiving an edge 122 of the touch surface 1 18. The second mounting 120 extends around the entire peripheral edge 122 of the touch surface 118. Both the first and second mountings 1 16, 120 are integral with the frame 102. In this way, the frame 102 can be extruded using a die comprising the cross-sectional shape of the first and second mountings 1 16, 120. In some alternative embodiments, the second mounting 120 can additionally or alternatively be screws, glue, or any other suitable fixture for securing the touch surface 1 18 to the elongate frame 102.

In some embodiments, the elongate frame 102 comprises at least two separate parts (not shown). The separate parts of the elongate frame 102 are fastented together with screws, tape or any other suitable fastening. For example, in the light diffuser 128 is mounted in one part of the elongate frame 102 and the substrate 1 14 is mounted on the other part of the elongate frame 128.

The elongate frame 102 will now be discussed in more detail with respect to Figure 2. Figure 2 is a close-up cross-sectional side view of the embodiment shown in Figure 1 .

An optical component mounting slot 124 is located at the corner of the top wall 104 and the side wall 108 of the elongate frame 102. At least a portion of the optical component mounting slot 124 is above the first mounting 1 16 and the second mounting 120 for respectively fixing the at least one light emitter 112 and the touch surface 1 18. In some embodiments, the internal surface 126 of the optical component mounting slot 124 provides a mounting surface 126 for mounting an optical component128. The mounting surface 126 is flat which keeps the optical component128 flat in the embodiments when the light diffuser 128 is a flexible element. The optical component128 will be described in further detail below.

In some embodiments, the optical component can be an optical component for modifying the properties of the emitted light incident on the optical component. In this case, the optical component can converge, diverge, reflect, or refract the incident light, or filter the light or modify a characteristic of the emitted light from the emitter 1 12 in any required way. In some embodiments, the optical component 128 is an optical film. In some embodiments, the optical component 128 is a light diffuser 128. Hereinafter the embodiments will refer to a light diffuser 128, but in other embodiments, the light diffuser 128 can be replaced with any other suitable optical component 128 for changing the characteristics of the emitted light incident on the optical component. Optical components are applied in the same way as described in reference to the light diffuser 128 in the embodiments below.

As shown in Figure 2, the optical component slot 124, or light diffuser mounting slot 124 (as it will be referred to hereinafter) is an open slot comprising an opening 132 in communication with an internal space 134 of the elongate frame 102. The light diffuser mounting slot 124 extends in the longitudinal axis B-B of the elongate frame 102. Accordingly, the light diffuser 128 when mounted in the light diffuser mounting slot 124 is in line with the light emitter 1 12 and a position above the touch surface 1 18 as indicated by the dotted arrow in Figure 1 . Optionally, the mounting surface 126 is the same width as the opening 132.

The light diffuser mounting slot 124 comprises a first lip 136 and a second lip 138 for retaining the light diffuser 128 inserted into the light diffuser mounting slot 124. In this way the first lip 136 and the second lip 138 project over the edges of the light diffuser 128.

In some embodiments, the light diffuser mounting slot 124 optionally comprises an elongate ridge 140 for engaging with the light diffuser 128. Accordingly, the elongate ridge 140 urges the light diffuser 128 against the first and second lips 136, 138. In this way, the light diffuser 128 is held in place in the light diffuser mounting slot 124 with a friction fit. This means that the mounting surface 126 is the surface on top of the elongate ridge 140. In other embodiments, the light diffuser mounting slot 124 does not comprise an elongate ridge 140 and the mounting surface 126 is the flat internal surface of the light diffuser mounting slot 124.

Optionally, the elongate ridge 140 pushes against the light diffuser 128 to deform the light diffuser 128 (not shown). Optionally, the elongate ridge 140 pushes against the light diffuser 128 to cause the light diffuser 128 to have a convex cross-sectional shape.

Optionally, the frictional forces between elongate ridge 140 and the light diffuser 128 is dependent on the relative materials used on for the light diffuser 128 and the elongate frame 102 and e.g. the elongate ridge 140.

Optionally, in some embodiments, the elongate ridge 140 is aligned opposite the opening 132 of the light diffuser mounting slot 124. Since the elongate frame 102 is extruded through a die, the minimum depth of a feature is approximately 1 mm. This means that the light diffuser mounting slot 124 cannot be less than 1 mm narrow when extruding the elongate frame 102. Accordingly, by providing an elongate ridge 140 opposite the opening 132 and protruding towards and / or into the opening 132, the light diffuser 128 having a thickness less than 1 mm can be held between the elongate ridge 140 and the first and second lips 136, 138. In some embodiments as shown in Figure 9, the separation D between the elongate ridge 140 and the first or the second lip 136, 138 in a direction perpendicular to the mounting surface 126 is less than 1 mm. In some embodiments, the separation D is equal to or less than the thickness of the light diffuser film 128. For example, the separation D is equal to or less than 0.3mm, or 0.2mm depending on whether the light diffuser film 128 comprises a backing layer or not. In some embodiments, the elongate ridge 140 extends out of the opening 132 beyond the first and the second lips 136, 138. Accordingly, if the light diffuser 128 is a flexible film 128, the light diffuser film 128 will bend around the elongate ridge 140 and the first and second lips 136, 138 as shown in Figure 9. This means that the light diffuser film 128 will maintain a convex shape when mounted in the light diffuser mounting slot 124.

In other embodiments, the elongate ridge 140 is not required, for example, the light diffuser 128 has a thickness greater than 1 mm or is not a flexible film.

Additionally, there can be a plurality of elongate ridges (not shown) for urging the light diffuser 128 against the first and second lips 136, 138. In other embodiments, the mounting surface 126 can be a separate component (not shown) inserted into the light diffuser mounting slot 124. In this way, the mounting surface element is inserted into the light diffuser mounting slot 124 together with the light diffuser 128.

Advantageously, by providing an integral mounting surface 126 which is part of the frame 102, the height H that the bezel 130 of the touch-sensitive device 100 protrudes above the touch surface 1 18 is reduced. This is because a bulky, separate diffusion component does not need to be secured to the elongate frame 102.

The light diffuser mounting slot 124 is aligned with the light emitter 1 12 for receiving and diffusing light over the touch surface 1 18. In this way, light emitted from the light emitter component 1 12 is incident on the light diffuser 128.

In order to promote the effective diffusion of light over the touch surface 1 18, the light diffuser mounting slot 124 and the light diffuser 128 are angled with respect to a plane A-A of the touch surface 1 18. In some embodiments, the angle of the light diffuser mounting slot 124 and / or the light diffuser 128 with respect to the plane A-A of the touch surface 1 18 is between 40 - 60 degrees.

In some embodiments, the angle of the light diffuser mounting slot 124 and / or the light diffuser 128 with respect to the plane A-A of the touch surface 1 18 is 45 degrees. In other embodiments, the angle can be varied depending on the diffusion properties (e.g. geometry, material, surface pattern) of the surface of the light diffuser 128. In some embodiments, the light diffuser 128 comprises a light diffusing surface which diffuses the incident emitted light across the touch surface 1 18.

In some embodiments, the light diffuser 128 is a flexible elongate strip of light diffusing material. In some embodiments, the light diffusing material is a light diffusing film 128. The light diffusing film 128 optionally comprises an adhesive backing (not shown) for adhering the light diffusing film 128 to the mounting surface 126. In some embodiments, fresh, unused light diffusive film 128 comprises a backing liner for covering the adhesive backing until application of the light diffusing film 128 to the mounting surface 126. Optionally, the light diffusing film can be mounted in the light diffuser mounting slot 124 whilst still comprising the backing liner because the light diffusing film 128 is held in place in the slot between the elongate ridge 140 and the first and second lips 136, 138.

In some embodiments, the light diffusing film 128 does not comprise a backing liner. In this case, the light diffusing film 128 comprises a tactile adhesive that is activated under pressure. This means that the light diffusing film 128 does not adhere to itself when stored. In other embodiments, the light diffusing film 128 does not comprise an adhesive backing. In this case, an adhesive is applied to the mounting surface 126 before the light diffusing film 128 is mounted on the mounting surface 126.

In some embodiments, the light diffusing film 128 comprises a width of 3.30mm. In some embodiments, the width of the light diffusing film 128 is the same as the width of the mounting surface 126 (not shown). In other embodiments, the width of the light diffusing film 128 is greater that the width of the mounting surface 126 on the elongate ridge 140. Indeed, by providing a width greater than the elongate ridge 140, the edges of the light diffusing film 128 are held in place by the first and second lips 136, 138 optionally without adhesive.

In some embodiments, the light diffuser mounting slot 124 is slightly wider than the width of the light diffusing film 128 in order that the light diffusing film 128 can be freely fed into the light diffuser mounting slot 124.

In this way, when the light diffusing film 128 is applied to the mounting surface 126, the light diffusing film 128 covers at least a portion of light diffuser mounting slot 124 which is exposed by the slot opening 132.

The thickness of the light diffusing film 128 with the backing liner is approximately 0.30mm. The thickness of the light diffusing film 128 without the backing liner is approximately 0.20mm and the thickness of the backing liner is approximately 0.1 mm. In other embodiments the width and the thickness of the light diffusing film 128 are varied. The light diffusing film 128 is flexible and is storable in a roll. This means that the length of the light diffusing film 128 can be any suitable length to match the length of the elongate frame 102. Advantageously, this means that the light diffusing film 128 can be dispensed and cut with a knife to match the length of the elongate frame 102.

Application of the light diffuser 128 to the elongate frame 102 will now be described with respect to Figures 4 to 8. Figures 4 to 8 show perspective views of the elongate frame and a tool 400 for applying the light diffuser 128 to the elongate frame 102.

Turning to Figure 4, a light diffuser application tool 400 for applying the light diffuser 128 to the elongate frame 102 will now be described in further detail. For the purposes of clarity, the tool 400 as shown in Figure 4 does not show the elongate frame 102. However, Figures 5 and 6 show the elongate frame 102 mounted in the tool 400.

The tool 400 comprises a jig 402 engageable with the elongate frame 102. The jig 402 comprises at least one reference surface 404 for aligning the elongate frame 102 in a predetermined position. In some embodiments, the jig 402, comprises first and second reference surfaces 404, 406 for engaging with the outer surface of the top wall 104 and the outer surface of the side wall 106. In this way, the vertex 200 defined by the surface of the top wall 104 and the surface side wall 106 is aligned with a reciprocal vertex 408 defined by the first and second reference surfaces 404, 406.

Whilst the jig 402 as shown in Figure 4 uses the vertices 200 and 408 to align the elongate frame 102 in the jig 402, any surface on the elongate frame 102 can be used to position a reference surface of a jig 402. Indeed, the jig 402 can be any suitable shape or size reciprocal to the elongate frame 102. The jig 402 as shown in Figure 4 is of a length which is reciprocal to a length of the elongate frame 102 as shown in Figure 3. Accordingly, the jig 402 can be any suitable length to accommodate the length of the elongate frame 102. The tool 400 comprises a light diffuser feeder 410 for receiving a light diffuser 128. The light diffuser feeder 410 comprises a feeding surface 412 for positioning and aligning the light diffuser 128 with respect to the jig 402. As can be seen from the Figure 4, the light diffuser 128 is positioned on the feeding surface 412. The light diffuser feeder 410 comprises a channel 414 with channel walls 416, 418 for constraining the side to side position of the light diffuser 128 on the feeding surface 412. The channel 414 narrows to a feeding mouth 420. The feeding mouth 420 is configured to receive the light diffuser 128 and position the light diffuser 128 in a side to side direction. The feeding mouth 420 comprises a bridge portion 422 for preventing movement of the light diffuser 128 in a vertical direction.

Turning to Figure 5, the elongate frame 102 is mounted in the jig 402. The elongate frame 102 has been inverted such that the vertex 200 is inserted into the jig 402. Accordingly, the top wall 104 and the side wall 106 are engaged with the first and second reference surfaces 404, 406. When the elongate frame 102 engages the jig 402, the light diffuser mounting slot 124 is aligned with the feeding mouth 420. In some embodiments, the feeding surface 412 is in the same plane as the light diffuser mounting slot 124. This means that when the light diffuser 128 is fed in to the feeding mouth 420 in the direction of the arrow shown in Figure 4, the light diffuser 128 is pushed into the light diffuser mounting slot 124.

Optionally, the elongate frame 102 is clamped to the jig 402 so that the elongate frame 102 is fixed with respect to the jig 402 during the application of the light diffuser 128 to the elongate frame 102.

In some embodiments, the user then manually pushes the light diffuser 128 with their finger. In this way, the user feeds the light diffuser 128 into the light diffuser mounting slot 124.

The jig 402 and the light diffuser feeder 410 are shown in Figures 4 and 5 as separate elements. The jig and the light diffuser feeder 410 are fixed with respect to each other so that the feeding surface 412 is positioned with respect to the first and second reference surfaces 404, 406.

In some embodiments, the jig 402 and the light diffuser feeder 410 are integral and a single element. In other embodiments, the light diffuser feeder 410 and the jig 402 are separable. Accordingly, different light diffuser feeders 410 are interchangeable with other jigs 402. This means that the jig 402 and the light diffuser feeder 410 can be configured for different size and shape light diffusers 128 and different sizes, shapes and orientations of the elongate frame 102.

Turning to Figure 6, another embodiment will now be described. Figure 6 shows a perspective view of an elongate frame 102 mounted in a light diffuser application tool 400 for applying the light diffuser 128. Figure 6 is the same as the embodiment as shown in Figure 5 except that the light diffuser feeder 410 comprises a feeding mechanism 600 for feeding the light diffuser 128 into the light diffuser mounting slot 124.

The feeding mechanism 600 comprises a first roller 602 and a second roller 604. The first and second rollers 602, 604 are rotatably mounted on the light diffuser feeder 410. For the purposes of clarity, the mounting frame for the first and second rollers 602, 604 are not shown. One or both of the first and second rollers 602, 604 are mounted on a drive shaft of an electric motor (not shown).

The first roller 602 is mounted above the feeding surface 412 and the second roller 604 is mounted below the feeding surface 412. In some embodiments, the rolling surfaces 606, 608 intersect with the feeding surface 412. In this way, when the light diffuser 128 is inserted between the first and second rollers 602, 604, the first and second rollers 602, 604 engage the top and bottom surfaces of the light diffuser 128 and the light diffuser 128 is urged by the rollers 602, 604 towards the jig 402. The light diffuser 128 is then fed into the light diffuser mounting slot 124. In another embodiment, there is only one roller 602 for urging the light diffuser 128 into the light diffuser mounting slot 124. For example, only the first roller 602 mounted above the feeding surface 412 is provided.

The one or two rollers 602, 604 grip the surface of the light diffuser 128 and push the light diffuser 128 into the light diffuser mounting slot 124. In some embodiments, the coefficient of friction of the rollers 602, 604 is higher than the coefficient of friction of the surface of the elongate frame 102. Accordingly, when the light diffuser 128 is fed into the light diffuser mounting slot 124, the rollers 602, 604 can continue to push the light diffuser 128 all the way through the light diffuser mounting slot 124.

In other embodiments, the feeding mechanism 600 can be any other suitable mechanism for pushing the light diffuser 128 into the light diffuser mounting slot 124. For example, the feeding mechanism 600 can comprise a rubber stopper mounted at the end of a reciprocating linkage (not shown) which stepwise pushes the light diffuser 128 into the light diffuser mounting slot 124.

Another embodiment will now be described with reference to Figure 7. Figure 7 shows another light diffuser application tool 700 for feeding the light diffuser 128 into the light diffuser mounting slot 124. The tool 700 is arranged to move relative to the elongate frame 102 and feed the light diffuser 128 into the light diffuser mounting slot 124 by pulling the light diffuser 128 though the light diffuser mounting slot 124.

The tool 700 comprises a body 710 having first and second projecting arms 712, 714. The first projecting arm 712 comprises a first reference surface 702 to engage the side 704 of the elongate frame 102. The second projecting arm 714 comprises a second reference surface 706 for engaging the top wall 104 of the elongate frame. The first and second reference surfaces 702, 706 maintained the relative position of the tool 700 with respect to the light diffuser mounting slot 124 as the tool 700 moves with respect to the elongate frame 102. In some embodiments, the first and second reference surfaces 702, 704 are in orthogonal planes to limit the relative movement of the tool 700 with respect to the elongate frame 102 only along the longitudinal axis B-B of the elongate frame 102.

The tool 700 is arranged to move in a direction parallel to the longitudinal axis B-B of the elongate frame 102 as shown in Figure 3.

The body 710 of the tool 700 comprises a light diffuser feeder arm 708 which projects from the body 710. The light diffuser feeder arm 708 is configured to protrude into the internal space 134 of the elongate frame 102 and into the light diffuser mounting slot 124. The light diffuser feeder arm 708 comprises a gripper 716 which grips an end of the light diffuser 128 to the light diffuser feeder arm 708. In some embodiments, the gripper 716 is a double-sided adhesive or a soft gasket. Alternatively, the gripper 716 is a fastening such as a clip, clamp, screw, pin, eye, glue or any other suitable means for fixing the light diffuser feeding arm 708 to the light diffuser 128.

In this way, when the tool 700 moves with respect to the elongate frame 102, the light diffuser 128 also moves with respect to the elongate frame 102. In this way, once the light diffuser feeding arm 708 is fixed to the end of the light diffuser 128, the tool 700 is threaded into one end of the elongate frame 102. At the same time, the light diffuser 128 is manually fed into the light diffuser mounting slot 124 by about 10mm. The tool 700 is then slid along the longitudinal axis B-B of the elongate frame 102 and the light diffuser 128 is pulled through and fed into the light diffuser mounting slot 124.

In some alternative embodiments, the tool 700 can be fixed and the elongate frame 102 is moved relative to the tool 700.

Another light diffuser application tool 800 will now be described in reference to Figure 8. Figure 8 shows a perspective view of the elongate frame 102 with a light diffuser application tool 800. The elongate frame 102 is the same as previously discussed in reference to the previous embodiments. The light diffuser application tool 800 comprises a light diffusing feeding arm 802 which is mounted to the end of the light diffuser 128. The light diffusing feeding arm 802 comprises a reference surface 804 for engaging with one or more internal surfaces 806 of the elongate frame 102. In this way, the light diffusing feeding arm 802 also comprises the reference surface 804. The light diffuser 128 is inserted manually into the light diffuser mounting slot 124 by about 10mm. The light diffusing feeding arm 802 then projects out of the internal space 134 which the user can grip and pull. The light diffuser 128 is then pulled through the light diffuser mounting slot 124 as described with reference to the embodiments shown in Figure 7.

In some embodiments, the light diffusing feeding arm 802 is fastened to the light diffuser 128 with adhesive. In other embodiments, the light diffusing feeding arm 802 is fastened to the light diffuser 128 with any suitable means such as a clip, clamp, screw, pin, eye, glue etc.

In some embodiments, the light diffusing feeding arm 802 can be rigid or flexible. For example, the light diffuser 128 is fixed to a pull tab or a thread for pulling the light diffuser 128 through the light diffuser mounting slot 124.

In another embodiment two or more embodiments are combined. Features of one embodiment can be combined with features of other embodiments.

Embodiments of the present invention have been discussed with particular reference to the examples illustrated. However, it will be appreciated that variations and modifications may be made to the examples described within the scope of the invention.