Patent Description:
Display devices generate heat during operation. Excessive heat can damage components of the display device, including for example light sources of the display device and electronic devices of the display device, such as a mainboard and individual components on the mainboard.

<CIT> discloses a method including providing access to a multi-panel display including a plurality of display panels. Each panel of the plurality of display panels is mounted onto a mechanical support structure. The method further includes identifying a defective panel from the plurality of display panels. Without powering down the multi-panel display, electrical connection to the defective panel is disconnected and the defective panel is removed from the mechanical support structure.

<CIT> discloses a display device including a body, a roller rotatable installed in the body, a flexible display configured to be wound or unwound from the roller in response to a rotation of the rolled, and a controller configured to change a screen size for displaying information related to a prescribed content in response to the winding or the unwinding of the flexible display.

<CIT> discloses a rotatory LED display device including rotating electrical machines and an LED display panel.

Each of <CIT> and <CIT> discloses a display device comprising a panel comprising a plurality of light sources for generating an image, and a mechanism comprising actuators for individually moving the light sources in response to receiving a control command from a processor.

The invention is set out by the appended claims.

As mentioned and is well known, display devices generate heat during operation. Excessive heat can damage or affect the performance of components of the display device, including for example light sources of the display device and electronic devices of the display device, such as a mainboard and individual components on the mainboard.

Various arrangements for cooling a display device are known. These typically include providing fans or air conditioning-type units to blow (cold) air across the whole display device or the light sources. Such use of fans or air conditioning-type units inevitably means that more power is consumed in powering the fans or air conditioning-type units. This is undesirable of itself and also can contribute to heating of the display device (because for example the fans or air conditioning-type units are inevitably close to the display device and so heat generated by the associated electric motors or air conditioning-type units, etc. in use can heat the display device directly or at least heat the environment in which the display device is located, resulting in heating of the display device).

Excessive heat is a particular problem with large display devices and display devices that are used outside, as in the case of for example so-called "signage" which may be used for displaying information, advertising, videos, etc. This is because the outside temperature can fluctuate over a wide range (particularly compared with indoor temperatures say) and also because of sunlight which may be directly incident on the display device.

In examples described herein, parts of a display device which are currently inactive (e.g. not displaying part of an image) are physically moved in order to separate them from the rest of the display device. This may comprise moving individual light sources which are (currently) inactive. A gap is thus created between the moved light source(s) and the rest of the display device, improving airflow around the active light sources of the display device. The improved airflow aids in cooling the active light sources.

In some examples, the display comprises a plurality of display modules, each display module comprising a plurality of light sources. In such examples, the modules correspond to movable parts of the display, and moving an inactive part comprises moving one or more of the display modules.

The display device may be a display device as used in or with many different types of consumer apparatus, including for example television screens or monitors, computer displays or monitors, and displays for other computing devices, etc. The display device may be a display device as used in public environments in so-called "signage", for example, for displaying adverts or for information or entertainment that is of interest to a larger audience, including for outdoor use as well as indoor use.

The light sources may be for example light sources that are used in a backlit display screen. In a backlit display device, the lit backlight has plural light sources for emitting light. The light sources may be for example LEDs (light emitting diodes). In a "direct-lit" backlight, the light sources are arranged typically in a regular array on a reflector panel. The light sources emit light which is directed through a diffuser to a display panel. The diffuser helps to reduce glare that can otherwise occur. The display panel is formed of or includes a number of display elements (which are also often referred to as "pixels" as they typically correspond to pixels in the image that is displayed). The display elements are controllable so as to selectively transmit or prevent light from the light sources passing through the display panel. The display elements may be for example LCDs (liquid crystal display devices). In a display device having a direct-lit backlight, generally there is a light source for each display element.

In another example, the light sources may be for example light sources that are used in an edge-lit backlight. That is, there is at least one light source which is arranged at or towards an edge of the display device. Commonly, there are light sources arranged around each of the four edges of a display device that has an edge-lit backlight. The light sources are typically elongate and may be for example coldcathode fluorescent lamps. In other examples, the light sources located at the edges are plural LEDs or other individual light sources arranged along the edges of the display device. The light sources may emit light into a light guide which is mounted in front of a reflector. The light guide directs the light through a diffuser into a display panel. Similarly to the direct-lit backlight example described above, the display panel may have plural individually controllable display elements. The display elements may be for example LCDs.

In other examples, the light sources may effectively generate the pixels directly, i.e. the light from the light source corresponds to the light required for that pixel and no backlight is required. (The light sources may for example generate coloured light or may generate white light which is then passed through controllable coloured filters so as to achieve different colours in the image. ) Display devices that generate the pixels directly include for example display devices that use OLEDs (organic light emitting diodes) and plasma technology. As another example, the light source may be an (inorganic) light-emitting diode (LED) and may be used as part of an LED display device, including for example an LED display or "wall" or a micro LED display. An area of particular application for the present disclosure is "signage", which often use display "walls" with a number of LEDs and which are often used in outside environments or other environments where the ambient temperature may not be well controlled.

<FIG> shows schematically a display device <NUM> in accordance with examples described herein. The display device <NUM> comprises a plurality of display modules <NUM>. Each display module <NUM> comprises a plurality of light sources <NUM>, such as for example LEDs. The modules <NUM> form a display with which static or moving images can be rendered by controlling the light sources <NUM> accordingly, as is known in the art. In the example of <FIG>, the display device <NUM> comprises twelve display modules <NUM> arranged in a 3x4 grid and each module <NUM> comprises forty-two light sources <NUM>. It is understood that this is a specific example for the purposes of explanation only. In general display modules <NUM> of the display device <NUM> will typically comprise many more light sources than shown schematically in <FIG>.

As mentioned above, the modules <NUM> of the display device <NUM>, or one or more individual components of the modules <NUM>, may be liable to overheating during operation. When displaying an image (e.g. a static or video image) on the display device <NUM>, one or more parts of the display <NUM> may be "inactive". Here, "inactive" refers to the case when the light sources <NUM> concerned are currently switched off or displaying a background part of an image.

<FIG> illustrates an example in which a particular module 101a is inactive and has thus been moved into the plane of the display (i.e. inwards, normal to the plane of the display). This movement creates an opening between the inactive module 101a and the other modules through which air can flow (here, in a direction from the front to back or vice versa of the display device <NUM>). The moving air acts to remove heat from the modules <NUM>, including particularly the active modules <NUM>, thus cooling them down.

The inactive module 101a is off (or displaying only background), meaning that it is not displaying any part (or at least any important part) of an image. Hence, there will be substantially no distortion to the image from a viewer's perspective. The inactive module 101a need only move a small amount in order to create the opening. In many situations, for example when the display device <NUM> is used as signage in an environment in which the viewers may not even be particularly close to the display device <NUM>, this is unlikely even to be noticed by viewers.

<FIG> illustrates an example system incorporating the display device <NUM> described above. The display device <NUM> in this example is provided with a mechanism <NUM> for selectively and controllably moving the panels <NUM> as described above.

The system comprises a controller <NUM> for controlling the display device <NUM> and the moving mechanism <NUM> of the display device <NUM>. The controller <NUM> comprises an input <NUM>, a processor <NUM> and an output <NUM>. The processor <NUM> is operatively coupled to each of the input <NUM> and the output <NUM>.

The input <NUM> comprises a data interface for receiving image data (which may be static or video image data) from a data storage <NUM>. For example, the input <NUM> may comprise hardware for connecting to the data storage <NUM> via a wired connection such as an Ethernet network connection or an HDMI connection, etc., or a wireless connection, such as a WiFi connection. Other interfaces are well known in the art. In some examples, the data storage <NUM> may be a DVD or Blu Ray storage device to be read by a DVD or Blu Ray player which then provides the image data to the processor <NUM>. It is understood that data storage <NUM> shown in <FIG> may represent any suitable computer storage of image data to be displayed on the display device <NUM>. This data storage <NUM> may be local to the controller <NUM> itself, or may be accessed via one or more networks, including the Internet.

The output <NUM> comprises hardware for transmitting data to the display device <NUM> to be displayed. In this example, the hardware of the output <NUM> is also configured to transmit control commands to the mechanism <NUM>. However, the controller <NUM> may in other examples comprise two separate outputs, one for controlling the display <NUM> and one for controlling the mechanism <NUM>.

The processor <NUM> is configured to receive image data from the data storage <NUM> via the input <NUM>, and transmit it to the display device <NUM> via the output <NUM> such that the image (static or video) is displayed on the display device <NUM>. This may comprise the processor <NUM> performing one or more intermediate steps such as decoding, decompressing, unencrypting, etc., as well known in the art.

The processor <NUM> is additionally configured to determine one or more inactive parts of the display device <NUM>. This comprises the processor <NUM> identifying light sources <NUM> or display modules <NUM> that are controlled to be off, or ones that are displaying a background region of the image. In the latter case, the processor <NUM> analyses the image data to determine background regions of the image.

In any case, the processor <NUM> is configured to determine one or more parts of the display device <NUM> which will be inactive when the image is rendered from the image data. The processor <NUM> is configured to, in response to determining an inactive part, send a control command to the mechanism <NUM> to cause the mechanism <NUM> to physically move at least one corresponding part(s) in order to separate that part (or those parts) from the rest of the display device <NUM>. As mentioned above, this may be performed on a single light source level in some examples. Alternatively, this may be performed on a display module level in other examples. That is, the light sources <NUM> may be arranged in fixed panels (the display modules <NUM> in this example) and the mechanism <NUM> may be constructed and arranged to move one or more panels of light sources <NUM> at a time.

The mechanism <NUM> comprises actuators for individually moving one or more light sources <NUM> (or display modules <NUM>) of the display device <NUM>. The actuators may be arranged to move (translate) the light sources <NUM> perpendicular to the display plane of the display device <NUM>, as shown in <FIG>. Alternatively or additionally, the mechanism <NUM> may comprise actuators for moving and/or rotating the light sources <NUM> in other directions. For example, the mechanism <NUM> may, in response to a control signal from the processor <NUM>, rotate an inactive display module <NUM> slightly, around for example a vertical or horizontal axis, in order to create a gap between that display module <NUM> and surrounding display modules <NUM>.

The display device <NUM> may, in addition to the mechanism <NUM>, comprise a sensor (not shown in the Figures) for determining whether or not it is currently raining. For example, a humidity sensor may be provided for detecting moisture around the display device <NUM>. Data from such a sensor may be provided to the processor <NUM>. In such cases, the processor <NUM> may be able to make a determination as to whether it is currently raining or not, based on the received data from the sensor. The processor <NUM> may then be configured to perform the step of controlling the mechanism <NUM> to move any inactive panels of the display device <NUM> only when it is not raining. Only moving the panels or module <NUM> (or individual light sources <NUM>) when it is not raining has the advantage or preventing rainwater entering a gap created by the movement. The processor <NUM> may perform the step of determining whether or not it is raining first, and may then not perform the step of determining inactive part(s) when it is raining.

Moreover, there may be a time delay or threshold, operated by for example the display device <NUM> or in particular the processor <NUM>, so that a light source <NUM> or a panel or module <NUM> is only moved once it has been inactive for a certain period of time. This is to avoid the light source <NUM> or module <NUM> being moved prematurely or too frequently simply because a light source <NUM> or all light sources <NUM> of the module <NUM> are briefly inactive. This may occur for example because the light sources <NUM> are off briefly because a black background is being displayed, or there is a brief pause between display of images. The threshold may be of the order of a few seconds to a minute or a few minutes say.

The controller <NUM> and its components as shown in <FIG> are represented as a schematic block diagram for the purposes of explaining the functionality of the controller <NUM> only. Hence, it is understood that each component of the controller <NUM> is a functional block for performing the functionality ascribed to it herein. Each component may be implemented in hardware, software, firmware, or a combination thereof. Additionally, although described as separate components of the controller <NUM>, some or all of the functionality may be performed by a single piece of hardware, software, or firmware.

It will be understood that the processor or processing system or circuitry referred to herein may in practice be provided by a single chip or integrated circuit or plural chips or integrated circuits, optionally provided as a chipset, an applicationspecific integrated circuit (ASIC), field-programmable gate array (FPGA), digital signal processor (DSP), graphics processing units (GPUs), etc. The chip or chips may comprise circuitry (as well as possibly firmware) for embodying at least one or more of a data processor or processors, a digital signal processor or processors, baseband circuitry and radio frequency circuitry, which are configurable so as to operate in accordance with the exemplary embodiments. In this regard, the exemplary embodiments may be implemented at least in part by computer software stored in (non-transitory) memory and executable by the processor, or by hardware, or by a combination of tangibly stored software and hardware (and tangibly stored firmware).

Reference is made herein to data storage for storing data. This may be provided by a single device or by plural devices. Suitable devices include for example a hard disk and non-volatile semiconductor memory.

Although at least some aspects of the embodiments described herein with reference to the drawings comprise computer processes performed in processing systems or processors, the invention also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice. The program may be in the form of non-transitory source code, object code, a code intermediate source and object code such as in partially compiled form, or in any other non-transitory form suitable for use in the implementation of processes according to the invention. The carrier may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a solidstate drive (SSD) or other semiconductor-based RAM; a ROM, for example a CD ROM or a semiconductor ROM; a magnetic recording medium, for example a floppy disk or hard disk; optical memory devices in general; etc..

Claim 1:
A method of operating a display device (<NUM>) using a controller (<NUM>); the controller (<NUM>) comprising an input (<NUM>) configured to receive image data to be displayed from a data storage (<NUM>), a processor (<NUM>) configured to send a control command, and an output (<NUM>) for transmitting the control command and the image data to the display device; the display device (<NUM>) having a panel comprising a plurality of light sources (<NUM>) for generating an image corresponding to the image data, and a mechanism (<NUM>) comprising actuators for individually moving the light sources (<NUM>), the mechanism (<NUM>) being constructed and arranged to physically move inactive light sources (<NUM>) in response to receiving the control command from the processor (<NUM>) to separate the inactive light sources (<NUM>) from active light sources (<NUM>), such that a gap is created between the inactive light sources (<NUM>) and the active light sources (<NUM>) through which air can flow; the method comprising:
the processor (<NUM>) of the controller (<NUM>) identifying the inactive light sources by:
identifying light sources (<NUM>) that are controlled to be off, wherein the inactive light sources are the light sources that are controlled to be off; or by
analysing the image data to determine background regions of the image, wherein the inactive light sources are the light sources (<NUM>) corresponding to the determined background regions of the image; and
in response to identifying the inactive light sources (<NUM>), the processor (<NUM>) sending a control command to cause the mechanism (<NUM>) of the display device (<NUM>) to separate the identified inactive light sources.