GB2379826A

GB2379826A - Audio visual apparatus comprising bending wave loudspeakers and electronic paper

Info

Publication number: GB2379826A
Application number: GB0122222A
Authority: GB
Inventors: Henry Azima; Nicholas Patrick Roland Hill
Original assignee: New Transducers Ltd
Current assignee: NVF Tech Ltd
Priority date: 2001-09-14
Filing date: 2001-09-14
Publication date: 2003-03-19
Also published as: GB0122222D0

Abstract

A visual display apparatus which comprises a loudspeaker having a diaphragm in the form of a panel 12 and an exciter 20 mounted on the panel. Electronic paper 18 which acts as a display is combined with the diaphragm. A film battery 76 may be attached to the diaphragm. The film battery comprises an electrolyte 78 mounted between two electrodes 80 and separated from each electrode by a separator 82. A network of such displays may be set up as a cellular network with the distribution of control and image data by mobile telephone.

Description

TITLE: AUDIO VISUAL APPARATUS DESCRIPTION The invention relates to device which has dual functionality providing both audio and visual output, including, in particular, but not exclusively, short life products, for example, signage, greetings cards and point of purchase displays.

In the field of display technology, high performance solutions have included LCD (liquid crystal displays), plasma, LED (light emitting diode) arrays and CRT (cathode ray tube) - based systems. The DMD mirror chip solution is also finding application in projection display systems.

These technologies are relatively costly and bulky and require significant electrical power to operate, unless they are small black and white LCD devices.

Conversely printed paper is low cost, high resolution, lightweight, and disposable but it has to printed and distributed.

For frequently altered signage, POP [point of purchase] displays and'barkers', which represent a very

substantial world market,"Electronic Paper"by Xerox Corporation or"E. Ink" presents an opportunity for rapid update of display information and also an opportunity to reduce costs. Electronic or electric paper is described in several patents and applications, including for example US 4126854 and US 5604027. Electronic paper technology provides a low current, battery operated display of high resolution in the form of a flexible laminated foil bearing data which may be readily updated. Such foils may comprise LEP (light emitting polymer) technology, e. g. of Cambridge Display Technology.

According to a first aspect of the invention, there is provided a combined audio-visual device comprising a loudspeaker having a diaphragm which is combined with a display formed from electronic paper. Thus electronic paper displays may be combined with speakers for'audiovisual output.

The loudspeaker may be a bending wave loudspeaker comprising a diaphragm capable of supporting bending wave vibration and an exciter mounted to the diaphragm to excite bending wave vibration in the diaphragm to produce an acoustic output. The advantages of low cost, slim and high articulation bending wave panel speakers complement those of electronic paper to provide a novel combination for audio-visual display.

The diaphragm may be in the form of a panel which may be a monolith or a composite panel formed from a core sandwiched between two skins. Electronic paper foil may be

laminated to a panel or may act as a skin of a composite panel. In some cases, and depending on area, electronic paper devices may be suitable for operation as bending wave speaker diaphragms.

Excitation of the bending wave panel may be by piezoelectric exciter for low cost applications or by electrodynamic transducer for higher quality applications.

The bending wave panel speaker may be resonant, e. g. of the kind described in W097/09842.

The data connection to the electronic paper, which may be two way or input only, may allow synchronisation of the'paper'display with the sound signals. Thus, for example, breaking announcements on the display may be audibly brought to the observer's attention.

Another aspect of the invention, is the use of a thin, flexible battery such as one described in WO 98/56458 or WO 97/22466 to provide power to a loudspeaker, for example, to an exciter mounted on an acoustic radiator of the loudspeaker. Such batteries have been developed by Power Paper Limited and may be rolled off a press like ink onto paper.

The thin battery may be particularly suitable for applications which require flat loudspeakers, for example, loudspeakers according to W097709842. The battery is preferably attached to the acoustic radiator and may thus add mass or stiffen the acoustic radiator. Accordingly, the characteristics of the acoustic radiator may need to be adapted to ensure optimum performance of a loudspeaker

powered by the battery.

In particular, a thin battery may be combined with the audio-visual device defined above to provide power to the exciter and/or the electronic paper. The thin battery may be laminated to the loudspeaker diaphragm panel or alternatively may be used as a skin in a composite panel.

The battery may be used as a rear skin and the electronic paper may be used as a front skin of a composite panel.

Another aspect of the invention is the organisation of many loudspeakers in a complex system which may range over an area such as an airport terminal or mall, or may cover many such places.

There is a need in large sound and visual data systems for data to be directed selectively or in groups and for the location of individual or sets of loudspeaker devices to be known to the transmitting unit.

According to the invention there is provided a system for organising a plurality of speakers, comprising a net, that is-a region divided into a set of cells with transmitter/receive functions for each cell linked together as a network to allow the remote speakers to be addressed individually or in pre-selected or programmed groups. The system may be used in conjunction with GPS [global positioning system] data One or more speaker may be an audio-visual unit or device as described above. The value for safety announcements and for selectively locally relevant marketing is great.

Each individual speaker/audio visual unit may carry some local intelligence and a low power microprocessor which handles recognition location signalling and data interface processing. The electronics may be in film form, like a credit card processor attached to the panel or carried in a module fixed via a decoupled mounting to the panel or alternatively placed locally.

Power for the speaker/audio-visual units may be wired, or may use onboard batteries or may be solar powered using rechargeable cell reservoirs. The onboard battery may be in the form of the ultrathin battery described above.

Signal connection to the speaker/audio-visual unit may be via a wired internet link, for example using low cost low data rate connection at night, to be stored for use afterward. The development of WAP facilities brings internet subset facilities to a wide range of dedicated applications as opposed to full computer installations.

Alternatively the 900 MHz radio band provides for relatively free use for local transmission of sound signals and data. Low cost, low power, two way radio devices are now available for such use e. g. from Minion in the form of the MinionNet, whose concept has similarities with the generalised cellphonè network. Thus, signal connection to the speaker/audio-visual unit may also be made by Minion or equivalent or by a similar low cost short range radio link.

The selective and group capable data interface made

possible by new communication technology, either wired or by radio, is applicable both to remote panel speakers, ordinary speakers and electronic paper panel speaker combinations.

The invention is diagrammatically illustrated, by way of example, in the accompanying drawings.

Figure 1 is a cross-section of an audio-visual device according to a first aspect of the invention; Figure 2 is a schematic of a first system for organising a plurality of speakers according to a second aspect of the invention; Figure 3 is a schematic of a second system for a loudspeaker according to a third aspect of the invention; Figure 4 is a cross-section of an audio-visual device according to another aspect of the invention, and Figure 5 is a cross-section of a panel for an audiovisual device according to another aspect of the invention.

Figure 1 shows an audio-visual device (10) which comprises a loudspeaker having a diaphragm in the form of a panel (12) and an exciter (20) mounted on the panel.

The panel comprises a core (14) sandwiched between a rear skin (16) on which the exciter is mounted and a front skin (18) which is formed from electronic paper. The electronic paper front skin (18) acts as a display. The panel speaker is capable of supporting resonant bending waves and thus the loudspeaker is of the kind described in W097/09842.

The exciter (20) is connected to a cable (22) along which a signal from an amplifier (24) is transmitted. The amplifier is powered by a power unit (26) which also powers the display, i. e. the electronic paper front skin.

The display is connected to the power unit (26) by a line (30) which also transmits data to the display.

The amplifier (24) also acts as a processor and receives information from a radio or wired data bus (28).

Thus, the audio-visual device may be considered to be an intelligent addressable bending wave speaker system. As shown in Figure 2, such speaker systems may be linked to form an addressable network.

In Figure 2, there is shown a schematic of a system for organising a plurality of addressable speaker systems or cells (32) which when considered together form a net or network of cells. There are N cells, namely cell A (34), cell B (36),..., cell N (38), each of which comprises

several speakers (33). Cell A (34) comprises"n" loudspeakers (33), namely S,, SI,---Sn Similarly, cells B and N comprise the same or a different number of speakers, namely S7, Sg,... Sn and Sll, S13'... Sn, respectively.

Each cell (34,36, 38) is connected via two-way links (40) which transmit or receive information from a wired or radio interface (42). The interface (42) is connected to a control (44) or exchange which controls whether the cells are addressed individually or in pre-selected or programmed groups. The control (44) is connected to a display (46) which displays data or sound signals from the

individual cells (34,36, 38). The control (44) is also connected to a control point (48) through which a user may control the data inputted or received from the net.

Figure 3 shows an alternative addressable loudspeaker (54). The loudspeaker (54) is connected to an amplifier (52) which receives data or audio information from a data processor (50). A data interface (56) which receives information via a radio or wired data bus (62) and which receives address code from a coding system (60) is connected to the data processor (50). The data processor (50), the amplifier (52), the data interface (56) and the coding system (60) all receive power from a power unit (58).

Figure 4 shows an audio-visual device (70) which is generally similar to that shown in Figure 1 and thus items in common are indicated with the same reference numbers.

The audio-visual device (70) comprises a loudspeaker having a diaphragm in the form of a panel (12) and an exciter (20). The panel comprises a core (14) sandwiched between a rear skin (16) and a front skin (18). As in the embodiment in Figure 1, the front skin (18) is formed from electronic paper which acts as a display. However, the device shown in Figure 4 differs from that of Figure 1, in that the exciter (20) is attached to the panel via a thin battery (72), e. g. as described in WO 97/22466, mounted on the rear face of the panel.

Figure 5 shows an alternative diaphragm for use in an audio-visual device. The diaphragm is in the form of a

panel (12) comprising a core (14) sandwiched between a rear skin and a front skin (18). As in the embodiment in Figure 4, the front skin (18) may formed from electronic paper which acts as a display. However, the rear skin is formed from a film battery (76), e. g. as described in WO 97/22466. As shown in the exploded section, the film battery comprises an electrolyte (78) mounted between two electrodes (80) and separated from each electrode by a separator (82). One electrode (80) touches the core (14) of the panel.

Claims

CLAIMS 1. Visual display apparatus comprising electronic paper combined with a loudspeaker diaphragm.
2. Visual display apparatus according to claim 1, comprising electronic paper foil laminated to the panel of a bending wave panel speaker.
3. Visual display apparatus according to claim 1, wherein electronic paper foil forms the skin of a composite bending wave panel speaker.
4. Visual display device according to any preceding claim, wherein the bending wave panel speaker is resonant.
5. Visual display device according to any preceding claim, comprising a data connection to the electronic paper to allow synchronisation of the display with a sound signal to the loudspeaker.
6. A system for organising a plurality of visual display devices as claimed in any preceding claim, comprising a net, that is a region divided into a set of cells with transmitter/receive functions for each cell linked together as a network to allow the remote speakers/displays to be addressed individually or in preselected or programmed groups.
7. A system according to claim 6, wherein individual display devices carry local intelligence, and a microprocessor to handle recognition location signalling and data interface processing.
8. A system according to claim 6 or 7, wherein signal connection to the display devices is via a wired internet

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link.
9. A system according to claim 6 or claim 7, wherein the display devices are connected via radio telephone.
10. Visual display device substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.
11. A system for organising a plurality of visual display systems substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.