GB2524813A

GB2524813A - Control unit with illuminated display

Info

Publication number: GB2524813A
Application number: GB1406043.8A
Authority: GB
Inventors: Steve Sells; Paul Neville
Original assignee: NAIM AUDIO Ltd
Current assignee: NAIM AUDIO Ltd
Priority date: 2014-04-03
Filing date: 2014-04-03
Publication date: 2015-10-07
Anticipated expiration: 2034-04-03
Also published as: GB201406043D0; GB2524813B

Abstract

A display panel for an electronic device, has a base unit and a cover screen on which a plurality of display symbols, such as play or pause symbols, are arranged, in use, to be visibly illuminated. Each display symbol is associated with a light emission chamber 132 formed in the base unit. Each light emission chamber is closed at the sides and base and has an associated light source such as LED 128 arranged to emit light therein. Each light emission chamber has an aperture 136 arranged such that an associated display symbol is, in use, indirectly illuminated by said light source through the aperture. A control unit may also be provided with graspable cylindrical bezel (112, figure 4) arranged around a display panel (106, figure 3) such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section.

Description

Intellectual Property Office Application No. GB1406043.8 RTIVI Date:6 October 2014 The following terms are registered trade marks and should be read as such wherever they occur in this document: Perspex Intellectual Property Office is an operating name of the Patent Office www.ipo.govuk Control Unit with Illuminated Display The present invention relates to a control unit with an illuminated display. More particularly, the present invention relates to a control unit with an illuminated display for use with an electronic device.

Electronic devices such as amplifiers, compact disc players, and mp3 players are well known in the art. Such devices often require a control panel and/or a display panel to enable a user to operate the device effectively.

It is known, and often desirable, to provide illumination for a control panel, for example, to indicate where to press to activate a particular function, or merely as an indicator of the operation of a particular function (e.g. confirmation that a given function has been activated).

However, an illuminated display presents a number of challenges, particularly in the context of high-end products. For example, an illuminated display may need to comprise symbols or indicia which are evenly illuminated. Inhomogeneous illumination leads to a reduction in perceived quality.

Further, the provision of light sources behind a display can lead to light leakage which results in areas of the display being illuminated which should not be. Again, this reduces the perceived quality of the product.

It is also known to provide physically-operable controls, for example a rotary controller or knob, to control functions of the electronic device, for example, the volume of an audio playback. Often, it is desired to illuminate the rotary controller for practical and aesthetic purposes.

However, a problem can arise when light emitting parts are used in conjunction with moving parts. Clearly, a certain clearance is required between the moving part and adjacent stationary parts to enable uninhibited movement of the moving part and to account for manufacturing tolerances. However, depending upon the location of the light

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source, such clearance may result in undesirable light patterns and light leakage from areas not intended to be illuminated.

For many high-end electronics products, such light leakage is unacceptable and undesirable. Such effects may reduce the perceived quality of the electronic device to the user.

However, the solution to the problems is often non-trivial. It is often not possible to mass-manufacture solutions where tolerances are such that light leakage is eliminated entirely, particularly when the user may be able to view the device orthogonal to a gap between static and moving parts. Further, providing light barriers or restrictions can often lead to undesirable bulk or complexity of the parts involved, or prohibitive manufacturing cost.

Therefore, a technical problem exists in the art that it is difficult to provide illumination which is uniformly and accurately applied to the desired areas whilst preventing undesirable light leakage. This is a particular problem where it is desired to illuminate movable components which are located close to stationary parts. The present invention addresses these issues.

According to a first aspect of the present invention, there is provided a display panel for an electronic device, comprising a base unit and a cover screen on which a plurality of display symbols are arranged, in use, to be visibly illuminated, wherein each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber being closed at the sides and base and having an associated light source arranged to emit light therein, wherein each light emission chamber comprises an aperture arranged such that an associated display symbol is, in use, indirectly illuminated by said light source through said aperture.

In one embodiment, the light source for each light emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen.

In one embodiment, the base unit comprises a light guide and a cover member, the sides and base of each light emission chamber being formed in said light guide and each aperture being formed in said cover member.

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In one embodiment, each light source is located on said cover member adjacent the respective aperture.

In one embodiment, each light source is located on a side of said cover member facing away from the cover screen.

In one embodiment, said cover member comprises a printed circuit board and each light source is connected to the printed circuit board.

In one embodiment, each light source comprises a surface mounted light emitting diode.

In one embodiment, the sides and base of each light emission chamber are formed from a respective recess in the light guide.

In one embodiment, the light guide comprises a reflective and/or light coloured material.

In one embodiment, the cover member comprises a non-reflective and/or dark coloured material.

In one embodiment, the sides and base of at least one light emission chamber comprises at least one curved surface.

In one embodiment, each light emission chamber, light source and respective aperture is sized and arranged such that there is no direct line of sight to the light source through the aperture.

In one embodiment, each light source comprises a light emitting diode.

In one embodiment, the display panel further comprises touch sensors operable to register touch events on at least one of said display symbols.

According to a second aspect of the present invention, there is provided a control unit for an electronic device comprising a base mount section, a display panel according to any one of the preceding claims and a rotatable control device arranged on said base mount section and comprising a graspable cylindrical bezel arranged around said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section.

In one embodiment, the display panel is substantially circular and the cylindrical bezel is arranged immediately adjacent the circumference of the display panel.

In one embodiment, said graspable cylindrical bezel is substantially flush with the cover screen of the display panel.

In one embodiment, said cylindrical bezel extends into said base mount section such that the entire display panel is located within said cylindrical bezel.

In one embodiment, the base mount section further comprises one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel.

In one embodiment, the base mount section comprises a plurality of outer light sources spaced about the outer circumference of said cylindrical bezel.

In one embodiment, the base mount section comprises a diffuser arranged around the outer circumference of said cylindrical bezel and operable to diffuse the light emission from said plurality of outer light sources.

In one embodiment, the rotatable control device is arranged to form a baffle to reduce light leakage between the one or more outer light sources and the display panel.

In one embodiment, the cylindrical bezel extends downwardly into said base mount section to form a baffle between the one or more outer light sources and the display panel.

In one embodiment, the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel.

In one embodiment, the rotatable control device further comprises a rotation detector for detecting rotation of said cylindrical bezel.

In one embodiment, said rotation detector comprises an electronic emitter and sensor located on said base mount section, and a ring located on said cylindrical bezel and comprising a plurality of protrusions, said ring being rotatable with said cylindrical bezel such that the protrusions of said ring pass between the emitter and sensor.

In one embodiment, the light guide is further arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible between the cylindrical bezel and the display panel.

According to a third aspect of the present invention, there is provided an electronic device comprising the display panel of the first aspect.

According to a fourth aspect of the present invention, there is provided an electronic device comprising the control unit of the second aspect.

In one embodiment, the electronic audio device is in the form of an audio player.

According to a fifth aspect of the present invention, there is provided a control unit for an electronic device comprising a display panel on which a plurality of display symbols are arranged, in use, to be visibly illuminated, a base mount section and a rotatable control device, the rotatable control device being arranged on said base mount section and comprising a graspable cylindrical bezel arranged around said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section, the base mount section comprising one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel and wherein the rotatable control device is arranged to function as a baffle to reduce light leakage between the one or more outer light sources and the display panel.

In one embodiment, the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel, the rotary bearing being located below the display panel and between the or each outer light source and the display panel.

In one embodiment, the display panel comprises a base unit and a cover screen on which said plurality of display symbols are arranged, in use, to be visibly illuminated, the base unit being arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible between the cylindrical bezel and the display panel.

In one embodiment, each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber being closed at the sides and base and having an associated inner light source arranged to emit light therein, wherein each light emission chamber comprises an aperture arranged such that an associated display symbol is, in use, indirectly illuminated by said inner light source through said aperture.

In one embodiment, the inner light source for each light emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen -In one embodiment, the base unit comprises a light guide and a cover member, the sides and base of each light emission chamber being formed in said light guide and each aperture being formed in said cover member.

In one embodiment, each inner light source is located on said cover member adjacent the respective aperture.

In one embodiment, each inner light source is located on a side of said cover member facing away from the cover screen.

In one embodiment, said cover member comprises a printed circuit board and each inner light source is connected to the printed circuit board.

In one embodiment, each inner light source comprises a surface mounted light emitting diode.

In one embodiment, the entire display panel is located within said cylindrical bezel.

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Embodiments of the present invention will now be described in detail with reference to the accompanying drawings, in which: Figure 1 is an isometric view of an electronic audio player suitable for use with the display panel of the present invention and/or control unit of the present invention; Figure 2 is a more detailed view of the electronic audio player of Figure 1 showing the control unit and display panel of the present invention in more detail; Figure 3 is an isometric view of a control unit according to an embodiment of the present invention; Figure 4 is an exploded isometric view of the control unit of Figure 3; Figure 5 is an enlarged view of the display panel forming part of the control unit shown in Figures 3 and 4; Figure 6 is an isometric section view showing part of the display panel of Figure 5; Figure 7 is an orthogonal section view showing part of the display panel of Figure 6; Figure 8 is an enlarged orthogonal section view showing part of the display panel of Figure 7; Figure 9 is an isometric section view taken through the control unit of Figure 3; Figure 10 is a perspective section view taken through the same line of the control unit as Figure 9; and Figure 11 is an orthogonal section view of the same section of the control unit shown in Figures 9 and 10.

Figure 1 is an isometric view of an electronic device in the form of an electronic audio device 10. The electronic audio device lOis arranged to play audio media received from any suitable source; for example, audio data streamed via a network, a compact disc (CD) player or other audio input.

The electronic audio device 10 comprises a housing 12 formed from a rigid material such as wood and/or metal. Within the housing 12 is located a plurality of loudspeakers 14.

The configuration, structure and operation of the loudspeakers 14 are not material to the present invention and will not be discussed further here.

In addition, the above-described audio device 10 is merely exemplary and the skilled person would readily be aware of alternative devices which could be used with the present invention.

The housing 12 comprises a substantially planar upper surface 16. A circular cut-out 18 is formed in the upper surface and is surrounded by a frustoconical chamfered recess 20.

A control unit 100 according to an embodiment of the present invention is located in within the cut-out 18 and the chamfered recess 20. The control unit 100 is arranged such that a user can readily gain access to the control functions of the control unit 100 whilst the control unit 100 does not extend beyond the level of the planar upper surface 16.

The control unit 100 is shown in more detail in Figures 3 and 4. Figure 3 shows an isometric view of the control unit 100 separate from the electronic audio device 10.

Figure 4 shows an exploded view of the components of the control unit 100.

The control unit 100 comprises a mount section 102, a rotary control element 104 and a display panel 106.

The mount section 102 is arranged to secure the control unit 100 to the remainder of the electronic audio device 10 and to enable electronic connections thereto to be established. The mount section 102 comprises a base 108 and an outer light guide 110.

The outer light guide 110 is at least partially constructed from a transparent or semi-transparent material, for example a plastic such as Perspex or ABS. This is, as will be described below, to enable the rotary control element 104 to be externally illuminated for practical and aesthetic reasons.

The rotary control element 104 comprises a graspable cylindrical bezel 112, a rotary bearing 114 and acastellation ring 116.

The graspable bezel 112 is manipulable by a user to adjust a parameter of the electronic audio device 10 in use, for example, the volume of an audio track or to select a particular mode of operation of the electronic audio device 10.

In this embodiment, the bezel 112 is formed from metal; for example, machined aluminium. Machined aluminium provides a high-quality tactile user experience.

However, other metals, or materials such as plastic, wood or metal/plastic hybrids could be used in place of aluminium.

The bezel 112 is arranged on the rotary bearing 114 which provides an interface between the stationary mount section 102 and the rotatable bezel 112. The rotary bearing 114 may take any suitable form; for example, the rotary bearing 114 may contain a race of ball bearings to provide smooth rotational movement.

The castellation ring 116 comprises a plurality of projecting castellations disposed around the perimeter of the castellation ring 116. The castellation ring 116 is, in use, connected to the bezel 112 and arranged to move therewith.

In use, the castellations are arranged to extend into the path between an infrared (IR) emitter and receiver forming part of a IR motion sensor 118 such that, as the bezel 112 is rotated, the projecting castellations intermittently block the transmission of IR radiation from the I Remitter to the IR sensor 118.

In this way, the speed and direction of rotation of the bezel 112 can be detected efficiently without recourse to mechanical devices which may impede the smooth movement of the bezel 112 and which may be susceptible to failure and damage in use.

The display panel 106 comprises three sections -a control board 120, an inner light guide 122 and a semi-transparent cover screen 124. The control board 120 and inner light guide 122 form, when assembled, a display panel base unit 126 to which the cover screen 124 is attached.

The semi-transparent cover screen 124 may be formed from a suitable plastic -for example, Acrylic, Perspex or ABS and is tinted such that the cover screen 124 appears black from a visual inspection and has relatively low transmissivity at visual wavelengths.

This is shown in exemplary Figures 1 and 2.

Figure 5 shows the three components of the display panel 106 in a more detailed exploded view.

The semi-transparent cover screen 124 may comprise etchings, bleachings or other portions having greater light transmissivity (or, expressed differently, reduced light absorption at visible wavelengths) than the remainder of the semi-transparent cover screen 124. These portions may be used to display information in the form of display symbols -for example, play, stop or pause symbols, or appropriate wording or numerics to display properties of the electronic audio device 10. These can be seen clearly in Figures 3 and 4.

The control board 120 comprises numerous functions to enable operation of the display panel 106. On the upper surface of the control board 120 (i.e. the surface facing the semi-transparent cover screen 124), a plurality of capacitive sensors (not shown) are arranged. The capacitive sensors are arranged to detect touch inputs on the surface of the semi-transparent cover screen 124 to operate functions of the electronic audio device 10. However, alternative arrangements may be used; for example, haptic sensors, touch-sensitive panels or other arrangements. The specific nature and configuration of the capacitive sensors are not material to the present invention and will not be discussed further here.

On the lower surface of the control board 120 (i.e. the side of the control board facing the inner light guide 122) is located a plurality of light emitting diodes (LED5) 128 (shown in Figures 7 and 8). In this embodiment, the LEDs 128 comprise white (or near-white) inorganic LEDs that are integrated directly onto the control board 120. White LEDs are generally formed from a UV or blue emitting semiconductor LED which excites a suitable phosphor to produce white light. The LED5 128 are surface mounted on the control board 120 which comprises a circuit board including each of the components necessary for electronic operation of display panel 106 portion of the control unit 100.

The inner light guide 122 is formed from moulded plastic and is arranged to connect to the lower surface of the control board 120. The inner light guide 122, when installed in the complete control unit 100, is arranged between the control board 120 and the mount section 102 as will be described below. The inner light guide 122 is, in use, arranged to form a light blocking/reflecting element as will be described below. Therefore, it is desirable for the inner light guide 122 to be of a light colour (for example, white) and/or to have a reflective coating.

The structure for illuminating the necessary elements to be displayed on the display panel will now be described with reference to Figures 5 to 8. Figure 5 has already been described. Figures 6 and 7 show two views of a vertical section taken through the control board 120 and inner light guide 122 when connected. Figure 8 is a magnified view of Figure 7.

It is desirable for an illuminated display element or symbol (e.g. a play or pause symbol) on the display panel to be illuminated homogeneously and without directionality. In other words, the symbol region should be uniformly lit and should be visible from multiple viewing angles. This provides for an improved user experience.

However, the emission pattern from the LED5 126 is neither directional nor homogeneous. An attempt to illuminate the symbol region(s) directly with the LED5 128 would, therefore, result in an inconsistent and inhomogeneous lighting effect.

Therefore, the display panel 106 of the present invention addresses this aspect. As shown in Figures 5 to 8, the control board 120 comprises a plurality of LEDs 128 that each extend downwardly, and emit light generally downwardly, from the control board 120.

The inner light guide 122 is arranged to be located adjacent, and in conformal contact with, the control board 120 such that the LED5 128 are located between the lower face of the control board 120 and the inner light guide 122.

The inner light guide 122 comprises a plurality of recesses 130 which define a plurality of light emission chambers 132. Each light emission chamber 132 is bounded by the walls 134 of the respective recess 130 and the lower face of the control board 120.

Each light emission chamber 132 further comprises an aperture 136 formed in the control board 120. Each aperture 136 corresponds to one or more emissive display symbols or display elements on the display panel 106. In many cases, each aperture 136 is shaped to represent the shape of the desired illuminated display symbol (e.g. a play or pause button). However, this need not be the case and more complex shapes (for example, indicia or complete words) can be achieved through a combination of aperture 136 size and etching/bleaching/marking on the cover screen 124.

The one or more LED5 128 within each light emission chamber 132 is located adjacent each aperture 136 and emits light in a direction generally away from the respective aperture 136. In other words, the desired illuminated display symbol is illuminated indirectly by the light source through the respective associated aperture 136.

As shown in Figures 5 to 8, the walls 134 of each recess 130 are formed in a specific shape with at least some smoothly-varying, curved surfaces. The walls 134 are, in this embodiment, white to reflect the most amount of the light from the LED5 128. The walls 134 may follow a specific shape (for example, the outline of the aperture 136) or may be more general.

In each case, the walls 134 are arranged such that, when the one or more LED 128 within each light emission chamber is illuminated, the light emission observed through the aperture 136 is generally homogeneous and omni-directional.

In embodiments, the walls 134 of a given light emission chamber 132 are curved in one dimension and straight in another, as shown in the example views of Figures 5 to 9.

Whilst the herein illustrated examples of the shape of the light emission chambers 132 show particular shapes and configurations, the skilled person would readily be aware of variations which fall within the scope of the present invention. For example, the light emission chambers 132 may be semi-circular, parabolic, oval, square or variations thereof as desired. The light emission chambers 132 may also comprise baffles or other partitions as required to achieve the desired indirect and substantially homogeneous illumination through the respective aperture 136.

Furthermore, because of the configuration where each LED 128 is effectively held within a chamber 132 which is closed save for the respective aperture 136, light leakage is minimised or eliminated entirely. In other words, each light emission chamber 132 is closed at the sides and base, and therefore the only path for light to exit the light emission chamber 132 is through the respective aperture 136. Therefore, when a respective LED 128 is illuminated, only light emission from the respective aperture 136 is observed.

To further reduce any light leakage from the arrangement, and to maintain colour purity, the control board 120 (which comprises a surface mount board, may be darkly and/or neutral coloured (for example, black). Further, the edges of the control board 120 may be coated with a reflective material (e.g. metal) to prevent internal reflection of light within the control board 120.

Figures 9, 10 and 11 show sectional views taken through the entire control unit 100.

Figure 9 is an isometric section view taken through the control unit 100. Figure 10 is a perspective section view taken through the same line of the control unit as Figure 9, and Figure 11 is an orthogonal section view of the same section of the control unit 100.

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The display unit 106 has been described above, and is secured to a central hub 138 of the light guide 110 of the mount section 102.

The rotary bezel 112 surrounds the display panel 106 and is rotatable relative thereto.

The rotary bearing 114 is located beneath the inner light guide 122 and provides the movable connection between the stationary mount section 102 and the rotary bezel 112.

As shown best in Figures 10 and 11, the castellation ring 116 is connected to the lower end of the rotary bezel 112.

The periphery of the mount section 102 surrounding the rotary bezel 112 is arranged to be illuminated in use. In this regard, a circumferential channel 140 is provided which surrounds the lower end of the rotary bezel 112. The channel 140 comprises a substantially planar base surface 142 defined by the base 108 and an upper housing 144 defined by the outer light guide 110.

The base surface 142 comprises, in this embodiment, a further circuit board which is arranged to contain additional circuit components and light sources as will be described below. The upper housing 144 forms, at a side adjacent the rotary bezel 112, a circumferential flange 146 which extends upwardly to form a guide for the rotary bezel 112. The upper housing 144 and circumferential flange 146 are formed from substantially transparent plastic.

A plurality of LEDs 148 is equi-spaced about the circumference of the base surface 142 of the circumferential channel 140. When illuminated, the LEDs 148 are arranged to emit light within the circumferential channel 140 which will be transmitted through the upper housing 144 and circumferential flange 146 and cause a "glowing" effect.

Thus, when the control unit 100 is located within the circular cut-out 18 and frusto-conical chamfered recess 20 of the electronic audio device 10, light emission from the LED5 146 will cause the outer edge of the rotary bezel 112 to "glow" through a combination of refraction, reflection and transmission through the transparent plastic of the upper housing 144 and circumferential flange 146. The only part of the upper housing 144 which will be visible to a user when so installed is the distal end 150 of the circumferential flange 146.

In order to provide a uniform "glow" around the entire circumference of the rotary bezel 112, it is necessary to diffuse the light from the LEDs 148 so that the glow appears continuous. To achieve this, the upper housing 144 adjacent the circumferential flange 146 comprises a plurality of holes 152 formed in the plastic. The holes 152 act to diffuse the light emission from the plurality of LED5 148 such that the light emission from the LEDs 148 appears, when viewed orthogonal to the radial direction of the mount section 102, to be a continuous ring.

Whilst the present embodiment comprises partially-cut holes, the skilled person would readily be aware that variations are possible. For example, the holes 152 may extend all the way through the material of the upper housing 144 as through-holes. Alternatively, other diffusing elements may be utilised; for example, frosted plastic, corrugations or other shapes which diffuse and/or redirect the light emitted from the LEDs 148 sufficiently result in a continuous, unbroken glow" of light emission around the rotary bezel 112.

Whilst light leakage has been described with reference to the display panel 106 and associated LEDs 128, it is also imperative that light leakage does not occur from the circumferentially arranged LED5 148. Since the upper housing 144 is a continuous moulding from transparent or semi-transparent plastic which extends into the centre of the control unit 100, there is a risk that stray light emission may be visible from within the bezel 112, i.e. between the control ring and the display panel 106.

The present invention addresses this problem. As shown in Figures 9, 10 and 11, the bezel 112 and attached rotary bearing 114 and castellation ring 116 of the rotary control device 104 extend downwardly so that there is no line of sight between the LEDs 148 and the space between the bezel 112 and the display panel 106. In otherwords, the bezel 112 and other rotatable elements extend below the illuminated region of the upper housing 144 and circumferential flange 146 and function as a baffle or barrier to prevent stray light from being visible between the necessary tolerance gaps between movable and static components.

Additionally, the inner light guide 122 acts as a blocking member for stray illumination from the LED5 148. Since the inner light guide 122 is formed from opaque and reflective/light coloured material, any stray illumination from below (i.e. from the LED5 148 reflected, transmitted or refracted through the upper housing 144) will be reflected back downwards or blocked by the inner light guide 122.

Therefore, the inner light guide 122 has a dual function in that it is arranged to reflect light from the LEDs 128 of the control board 120 precisely upwards to illuminate the necessary control symbols, whilst blocking or reflecting any light emerging upwards from the LEDs 148 of the mount section 102.

The above arrangement according to the present invention provides a cost-effective and reliable approach to effective and homogeneous light emission where light leakage between components is minimised or eliminated. Such arrangements enables well- defined light emission zones to be provided whilst using non-specialist, pseudo omni-directional components such as surface mount inorganic LEDs. This enables an electronics product to have a high standard of perceived quality whilst using cost-effective and reliable components.

As described above, in use, the control unit 100 is integrated into the electronic audio device 10. In this embodiment, the electronic audio device 10 is configured to play audio media received from a suitable source; for example, audio data streamed via a network, a compact disc (CD) player or other audio input. The audio media is played from the plurality of loudspeakers 14.

In use, a user can control the operation functions of the electronic audio device 10 using the control unit 100. In one non-limiting example, the absence of a control input from the user, the display panel 106 and outer ring illumination (from the LEDs 148) are arranged to be switched off. Therefore, in this embodiment, the display panel 106 will appear entirely black due to the semi-transparent cover screen 124.

The user may then, for example, choose to play an audio track. This may be done by means of a remote control or "smartphone" (not shown), or may be initiated by a user touching the display panel 106 or bezel 112. This may be detected by the capacitance sensors as a touch event, or movement of the bezel 112 may be detected.

In either case, such an initial control input will cause at least a portion of the display panel 106 to be illuminated. This involves the illumination of one or more of the downwardly-directed LED5 128 which will illuminate a given light emission chamber 132 and, via the respective aperture 136, cause the respective control symbol to be illuminated. The outer illumination of the bezel 112 (via the LED5 148) may also occur at this point.

The user can then press, for example, the play control symbol on the display panel 106, and the audio media will begin to play. The user can then adjust the volume by rotating the bezel 112 as appropriate. Rotation of the bezel 112 will cause the castellation ring 116 to rotate relative to the IR emitter and sensor. This will be detected as a mark-space ratio by the I R sensor 118 and from this, the speed and direction of rotation of the bezel 112 can be determined. The volume can then be adjusted as appropriate.

When the volume is adjusted in this manner, the outer illumination of the bezel 112 (via the LEDs 148) assists the user. A plurality of peripheral volume segments may also be illuminated around the circumference of the display panel 106.

It is further noted that the brightness of the illuminated symbols or illuminated segments may be varied as required -e.g. by the user or automatically in response to certain parameters such as room brightness or via a pre-determined program such as a fade in or fade out.

Once the user has adjusted the volume to the desired level and has removed hislher hand from the bezel 112, after a particular pehod of time then the illumination on the outer ring and the display panel 106 will be switched off or dimmed if programmed to do so.

Variations of the above arrangement will be apparent to the skilled person. The specific configuration of components may vary and still fall within the scope of the present invention.

For example, light sources other than LEDs may be used. Alternative colours of light source may also be used.

The control unit as described need not be used solely with the exemplary audio device of Figures 1 and 2. To the contrary, the control unit may be used with numerous other electronic devices, for example audio-or audio-visual based devices for use in domestic, business, automotive, aeronautical or industrial environments. The skilled person would readily be aware of devices which would be suitable for use with the control unit and/or display panel of the present invention.

Embodiments of the present invention have been described with particular reference to the examples illustrated. While specific examples are shown in the drawings and are herein described in detail, it should be understood, however, that the drawings and detailed description are not intended to limit the invention to the particular form disclosed. It will be appreciated that variations and modifications may be made to the examples described within the scope of the present invention.

Claims

CLAIMS1. A display panel for an electronic device, comprising a base unit and a cover screen on which a plurality of display symbols are arranged, in use, to be visibly illuminated, wherein each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber being closed at the sides and base and having an associated light source arranged to emit light therein, wherein each light emission chamber comprises an aperture arranged such that an associated display symbol is, in use, indirectly illuminated by said light source through said aperture.
2. A display panel according to claim 1, wherein the light source for each light emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen.
3. A display panel according to claim 1 or 2, wherein the base unit comprises a light guide and a cover member, the sides and base of each light emission chamber being formed in said light guide and each aperture being formed in said cover member.
4. A display panel according to claim 3, wherein each light source is located on said cover member adjacent the respective aperture.
5. A display panel according to claim 4, wherein each light source is located on a side of said cover member facing away from the cover screen.
6. A display panel according to any one of claims 3 to 5, wherein said cover member comprises a printed circuit board and each light source is connected to the printed circuit board.
7. A display panel according to claim 6, wherein each light source comprises a surface mounted light emitting diode.
8. A display panel according to any one of claims 3 to 7, wherein the sides and base of each light emission chamber are formed from a respective recess in the light guide.
9. A display panel for an electronic device according to any one of claims 3 to 8, wherein the light guide comprises a reflective and/or light coloured material.
10. A display panel for an electronic device according to any one of claims 3 to 9, wherein the cover member comprises a non-reflective and/or dark coloured material.
11. A display panel according to any one of the preceding claims, wherein the sides and base of at least one light emission chamber comprises at least one curved surface.
12. A display panel according to any one of the preceding claims, wherein each light emission chamber, light source and respective aperture is sized and arranged such that there is no direct line of sight to the light source through the aperture.
13. A display panel according to any one of the preceding claims, wherein each light source comprises a light emitting diode.
14. A display panel according to any one of the preceding claims, further comprising touch sensors operable to register touch events on at least one of said display symbols.
15. A control unit for an electronic device comprising a base mount section, a display panel according to any one of the preceding claims and a rotatable control device arranged on said base mount section and comprising a graspable cylindrical bezel arranged around said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section.
16. A control unit according to claim 15, wherein the display panel is substantially circular and the cylindrical bezel is arranged immediately adjacent the circumference of the display panel.
17. A control unit according to claim 15 or 16, wherein said graspable cylindrical bezel is substantially flush with the cover screen of the display panel.
18. A control unit according to claim 15, 160117, wherein said cylindrical bezel extends into said base mount section such that the entire display panel is located within said cylindrical bezel.
19. A control unit according to claim 15, wherein the base mount section further comprises one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel.
20. A control unit according to claim 19, wherein the base mount section comprises a plurality of outer light sources spaced about the outer circumference of said cylindrical bezel.
21. A control unit according to claim 20, wherein the base mount section comprises a diffuser arranged around the outer circumference of said cylindrical bezel and operable to diffuse the light emission from said plurality of outer light sources.
22. A control unit according to any one of claims 19 to 21, wherein the rotatable control device is arranged to form a baffle to reduce light leakage between the one or more outer light sources and the display panel.
23. A control unit according to claim 22, wherein the cylindrical bezel extends downwardly into said base mount section to form a baffle between the one or more outer light sources and the display panel.
24. A control unit according to any one of claims 15 to 23, wherein the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel.
25. A control unit according to any one of claims 15 to 24, wherein the rotatable control device further comprises a rotation detector for detecting rotation of said cylindrical bezel.
26. A control unit according to claim 25, wherein said rotation detector comprises an electronic emitter and sensor located on said base mount section, and a ring located on said cylindrical bezel and comprising a plurality of protrusions, said ring being rotatable with said cylindrical bezel such that the protrusions of said ring pass between the emitter and sensor.
27. A control unit according to any one of claims 20 to 25 when comprising the display panel of any one of claims 3 to 10, wherein the light guide is further arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible between the cylindrical bezel and the display panel.
28. An electronic device comprising the display panel of any one of claims ito 14.
29. An electronic device comprising the control unit of any one of claims 15 to 26.
30. An electronic device according to claim 28 or 29, in the form of an audio player.
31. A control unit for an electronic device comprising a display panel on which a plurality of display symbols are arranged, in use, to be visibly illuminated, a base mount section and a rotatable control device, the rotatable control device being arranged on said base mount section and comprising a graspable cylindrical bezel arranged around said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section, the base mount section comprising one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel and wherein the rotatable control device is arranged to function as a baffle to reduce light leakage between the one or more outer light sources and the display panel.
32. A control unit according to claim 31, wherein the cylindrical bezel extends downwardly into said base mount section to form a baffle between the one or more outer light sources and the display panel.
33. A control unit according to claim 32, wherein the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel, the rotary bearing being located below the display panel and between the or each outer light source and the display panel.
34. A control unit according to claim 32 or 33, wherein the rotatable control device further comprises a rotation detector for detecting rotation of said cylindrical bezel.
35. A control unit according to claim 34, wherein said rotation detector comprises an electronic emitter and sensor located on said base mount section, and a ring located on said cylindrical bezel and comprising a plurality of protrusions, said ring being rotatable with said cylindrical bezel such that the protrusions of said ring pass between the emitter and sensor.
36. A control unit according to any one of claims 31 to 35, wherein the display panel is substantially circular and the cylindrical bezel is arranged immediately adjacent the circumference of the display panel.
37. A control unit according to any one of claims 31 to 36, wherein the display panel comprises a base unit and a cover screen on which said plurality of display symbols are arranged, in use, to be visibly illuminated, the base unit being arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible between the cylindrical bezel and the display panel.
38. A control unit according to claim 37, wherein each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber being closed at the sides and base and having an associated inner light source arranged to emit light therein, wherein each light emission chamber comprises an aperture arranged such that an associated display symbol is, in use, indirectly illuminated by said inner light source through said aperture.
39. A control unit according to claim 38, wherein the inner light source for each light emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen.
40. A control unit according to claim 38 or 39, wherein the base unit comprises a light guide and a cover member, the sides and base of each light emission chamber being formed in said light guide and each aperture being formed in said cover member.
41. A control unit according to claim 40, wherein each inner light source is located on said cover member adjacent the respective aperture.
42. A control unit according to claim 41, wherein each inner light source is located on a side of said cover member facing away from the cover screen.
43. A control unit according to any one of claims 40 to 42, wherein said cover member comprises a printed circuit board and each inner light source is connected to the printed circuit board.
44. A control unit according to claim 43, wherein each inner light source comprises a surface mounted light emitting diode.
45. A control unit according to any one of claims 40 to 44, wherein the sides and base of each light emission chamber are formed from a respective recess in the light guide.
46. A control unit for an electronic device according to any one of claims 40 to 44, wherein the light guide comprises a reflective and/or light coloured material.
47. A control unit for an electronic device according to any one of claims 40 to 45, wherein the cover member comprises a non-reflective and/or dark coloured material.
48. A control unit according to any one of claims 37 to 47, wherein said graspable cylindrical bezel is substantially flush with the cover screen of the display panel.
49. A control unit according to any one of claims 31 to 47, wherein the entire display panel is located within said cylindrical bezel.
50. A control unit according to any one of claims 31 to 49, wherein the base mount section comprises a plurality of outer light sources spaced about the outer circumference of said cylindrical bezel.
51. A control unit according to claim 50, wherein the base mount section comprises a diffuser arranged around the outer circumference of said cylindrical bezel and operable to diffuse the light emission from said plurality of outer light sources.
52. An electronic device comprising the control unit of any one of claims 31 to 51.
53. An electronic device according to claim 52, in the form of an audio player.
54. A display panel substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings.
55. A control unit for an electronic device substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings.
56. An electronic device substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings.
57. An audio device substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS:.- 1. A display panel for an electronic device, comprising a base unit and a cover screen on which a plurality of display symbols are arranged, in use, to be visibly illuminated, the base unit comprising a light guide and a cover member, wherein each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber having sides and a base formed in the light guide and an aperture formed in the cover member, each light emission chamber being closed at the sides and base and having an associated light source arranged to emit light therein, wherein the aperture of each light emission chamber is arranged such that an associated display symbol is, in use, indirectly illuminated by said light source through said aperture.2. A display panel according to claim 1, wherein the light source for each light 15 emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen.C'\J 3. A display panel according to claim 1 or 2, wherein each light source is located on said cover member adjacent the respective aperture. 0 204. A display panel according to claim 3, wherein each light source is located on a side of said cover member facing away from the cover screen.5. A display panel according to any one of the preceding claims, wherein said cover member comprises a printed circuit board and each light source is connected to the printed circuit board.6. A display panel according to claim 5, wherein each light source comprises a surface mounted light emitting diode.7. A display panel according to any one of the preceding claims, wherein the sides and base of each light emission chamber are formed from a respective recess in the light guide.8. A display panel for an electronic device according to any one of the preceding claims, wherein the light guide comprises a reflective and/or light coloured material.9. A display panel for an electronic device according to any one of the preceding claims, wherein the cover member comprises a non-reflective and/or dark coloured material.10. A display panel according to any one of the preceding claims, wherein the sides and base of at least one light emission chamber comprises at least one curved surface.11. A display panel according to any one of the preceding claims, wherein each light emission chamber, light source and respective aperture is sized and arranged such that there is no direct line of sight to the light source through the aperture. 15 12. A display panel according to any one of the preceding claims, wherein each light source comprises a light emitting diode.13. A display panel according to any one of the preceding claims, further comprising touch sensors operable to register touch events on at least one of said display symbols. 0 2014. A control unit for an electronic device comprising a base mount section, a display panel according to any one of the preceding claims and a rotatable control device arranged on said base mount section and comprising a graspable cylindrical bezel arranged around said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section.15. A control unit according to claim 14, wherein the display panel is substantially circular and the cylindrical bezel is arranged immediately adjacent the circumference of the display panel.16. A control unit according to claim 14 or 15, wherein said graspable cylindrical bezel is substantially flush with the cover screen of the display panel.17. A control unit according to claim 14, 150116, wherein said cylindrical bezel extends into said base mount section such that the entire display panel is located within said cylindrical bezel.18. A control unit according to claim 14, wherein the base mount section further comprises one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel.19. A control unit according to claim 18, wherein the base mount section comprises a plurality of outer light sources spaced about the outer circumference of said cylindrical bezel.20. A control unit according to claim 19, wherein the base mount section comprises a diffuser arranged around the outer circumference of said cylindrical bezel and operable to diffuse the light emission from said plurality of outer light sources.21. A control unit according to any one of claims 18 to 20, wherein the rotatable C\I control device is arranged to form a baffle to reduce light leakage between the one or more outer light sources and the display panel. 0 2022. A control unit according to claim 21, wherein the cylindrical bezel extends downwardly into said base mount section to form a baffle between the one or more outer light sources and the display panel.23. A control unit according to any one of claims 14 to 22, wherein the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel.24. A control unit according to any one of claims 14 to 23, wherein the rotatable control device further comprises a rotation detector for detecting rotation of said cylindrical bezel.25. A control unit according to claim 24, wherein said rotation detector comprises an electronic emitter and sensor located on said base mount section, and a ring located on said cylindrical bezel and comprising a plurality of protrusions, said ring being rotatable with said cylindrical bezel such that the protrusions of said ring pass between the emitter and sensor.26. A control unit according to any one of claims 19 to 24, wherein the light guide is further arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible between the cylindrical bezel and the display panel.27. An electronic device comprising the display panel of any one of claims ito 13.28. An electronic device comprising the control unit of any one of claims 14 to 26.29. An electronic device according to claim 27 or 28, in the form of an audio player.30. A control unit for an electronic device comprising a display panel on which a plurality of display symbols are arranged, in use, to be visibly illuminated, a base mount section and a rotatable control device, the rotatable control device being arranged on said base mount section and comprising a graspable cylindrical bezel arranged around 0 20 said display panel such that the cylindrical bezel is rotatable about an axis of rotation with respect to the display panel and base mount section, the base mount section comprising one or more outer light sources arranged to illuminate the outer circumference of said cylindrical bezel and wherein the rotatable control device is arranged to function as a baffle to reduce light leakage between the one or more outer light sources and the display panel.31. A control unit according to claim 30, wherein the cylindrical bezel extends downwardly into said base mount section to form a baffle between the one or more outer light sources and the display panel.32. A control unit according to claim 31, wherein the rotatable control device further comprises a rotary bearing to provide a rotatable connection between the base mount section and the cylindrical bezel, the rotary bearing being located below the display panel and between the or each outer light source and the display panel.33. A control unit according to claim 31 or 32, wherein the rotatable control device further comprises a rotation detector for detecting rotation of said cylindrical bezel.34. A control unit according to claim 33, wherein said rotation detector comprises an electronic emitter and sensor located on said base mount section, and a ring located on said cylindrical bezel and comprising a plurality of protrusions, said ring being rotatable with said cylindrical bezel such that the protrusions of said ring pass between the emitter and sensor.35. A control unit according to any one of claims 30 to 34, wherein the display panel is substantially circular and the cylindrical bezel is arranged immediately adjacent the circumference of the display panel.36. A control unit according to any one of claims 30 to 35, wherein the display panel comprises a base unit and a cover screen on which said plurality of display symbols are arranged, in use, to be visibly illuminated, the base unit being arranged to block and/or reflect light emission from the one or more outer light sources such that, in use, substantially no light emission from said one or more outer light sources is visible O 20 between the cylindrical bezel and the display panel. (437. A control unit according to claim 36, wherein each display symbol is associated with a light emission chamber formed in said base unit, each light emission chamber being closed at the sides and base and having an associated inner light source arranged to emit light therein, wherein each light emission chamber comprises an apeiture arranged such that an associated display symbol is, in use, indirectly illuminated by said inner light source through said aperture.38. A control unit according to claim 37, wherein the inner light source for each light emission chamber is arranged to emit light into the respective emission chamber in a direction away from the cover screen.39. A control unit according to claim 37 0138, wherein the base unit comprises a light guide and a cover member, the sides and base of each light emission chamber being formed in said light guide and each aperture being formed in said cover member.40. A control unit according to claim 39, wherein each inner light source is located on said cover member adjacent the respective aperture.41. A control unit according to claim 40, wherein each inner light source is located on a side of said cover member facing away from the cover screen.42. A control unit according to any one of claims 39 to 41, wherein said cover member comprises a printed circuit board and each inner light source is connected to the printed circuit board. 15 43. A control unit according to claim 42, wherein each inner light source comprises a surface mounted light emitting diode.44. A control unit according to any one of claims 39 to 43, wherein the sides and base of each light emission chamber are formed from a respective recess in the light 0 20 guide. (445. A control unit for an electronic device according to any one of claims 39 to 43, wherein the light guide comprises a reflective and/or light coloured material.46. A control unit for an electronic device according to any one of claims 39 to 44, wherein the cover member comprises a non-reflective and/or dark coloured material.47. A control unit according to any one of claims 36 to 46, wherein said graspable cylindrical bezel is substantially flush with the cover screen of the display panel.48. A control unit according to any one of claims 30 to 46, wherein the entire display panel is located within said cylindrical bezel.49. A control unit according to any one of claims 30 to 48, wherein the base mount section comprises a plurality of outer light sources spaced about the outer circumference of said cylindrical bezel.50. A control unit according to claim 49, wherein the base mount section comprises a diffuser arranged around the outer circumference of said cylindrical bezel and operable to diffuse the light emission from said plurality of outer light sources.51. An electronic device comprising the control unit of any one of claims 30 to 50.52. An electronic device according to claim 51, in the form of an audio player.53. A display panel substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings. L01554. A control unit for an electronic device substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings. (455. An electronic device substantially as hereinbefore described and/or illustrated 0 20 with reference to the accompanying drawings.56. An audio device substantially as hereinbefore described and/or illustrated with reference to the accompanying drawings.