Vehicle display device

Abstract

There is provided a vehicle display device (1). The vehicle display device (1) comprises: a circuit board; an array of light-emitting diode (LED) pairs (2) arranged on the circuit board, at least some

Description

This invention relates generally to a vehicle display device. More specifically, although not exclusively, this invention relates to a vehicle display device which can operate either in a visible light mode or in a black-out mode. Vehicles typically have display screens which display information, such as a dashboard with an array of light emitting diodes (LEDs) present to display operational information such as vehicle speed, fuel level, and engine speed. Sometimes, such display screens are LED display screens which do not have liquid crystals, such that the information is provided to the user directly from the LEDs. An example of such an LED screen is a dot matrix LED screen. At least some information is usually displayed when the vehicle is first switched on for use, for example the dashboard will light up when the vehicle is started. When the vehicle is started at night, this means that the LEDs are likely to be visible from outside of the vehicle. This may be problematic for some vehicles, for example military vehicles, which are required to operate in environments in which external visibility is detrimental. For example, if a military vehicle, which is located in a hostile environment, is started at night, then the energising of the LEDs might alert an aggressor as to the location of the vehicle. It is known to overcome this problem by disabling the LEDs. However, when the LEDs are disabled there is no operational information available to the user of the vehicle, which is clearly undesirable. Another solution is to provide a secondary display which has infra-red (IR) LEDs, which provide essential information, such that the user is able to receive the essential information while wearing night-vision eyewear. However, this adds complexity to the control means which controls which information is displayed, and the secondary display must generally be provided separately to the visible light display, reducing the space available for other vehicle equipment such as heaters, or other equipment required by the user, as well as being less ergonomic for the user to look at. Also, the provision of a secondary display does not always eliminate the problem, as the user may forget to disable the visible light display, especially during start-up of the vehicle. It would therefore be advantageous to overcome at least some of these limitations. Accordingly, aspects of the invention are as set out in the appended claims. Another aspect of the invention provides a vehicle display device. The vehicle display device may comprise an array of light-emitting diodes (LED). The vehicle display device may comprise a control means. The control means may be operatively connected to the LEDs, e.g. for displaying operational information relating to the vehicle. The LEDs may comprise first LEDs or visible LEDs or visible light LEDs, which may be operable to emit visible light. The LEDs may comprise second LEDs or infrared LEDs or infrared light LEDs, which may be operable to emit infrared light. The second LEDs may be configured to emit no visible light. The light emitted by the second LEDs may be devoid of visible light. The control means may be configured to selectively energise, in use, the first LEDs and / or the second LEDs to display the operational information. The control means may be configured to operate, in use, in a visible light mode. The control means may be configured to selectively energise the first LEDs, for example in the visible light mode, to display the operational information. The control means may be configured to operate, in use, in a black-out mode. The control means may be configured to selectively energise the second LEDs, for example in the black out mode, to display the operational information. The array of LEDs may comprise a first array or sub-array of the first LEDs. The first array or sub-array may comprise a visible light array. The array of LEDs may comprise a second array or sub-array of the second LEDs. The second array or sub-array may comprise an infrared light array or a black-out array. The second array or sub-array of LEDs may overlap at least partially, or may be at least partially embedded within, the first array or sub-array of LEDs. The array of LEDs may comprise an array of LED pairs. Each LED pair may comprise a first LED operable to emit visible light. Each LED pair may comprise a second LED operable to emit infrared light. Another aspect of the invention provides a vehicle display device comprising an array of light-emitting diode (LED) pairs and a control means operatively connected to the LED pairs for displaying operational information relating to the vehicle, each LED pair comprising a first LED operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in either a visible light mode, in which it is configured to selectively energise the first LEDs to display the operational information, or in a black-out mode, in which it is configured to selectively energise the second LEDs to display the operational information. The provision of an array of LED pairs enables the same information to be displayed in either one or both visible light or infrared light. As such, the position of the display remains effectively unchanged. The control means may, but need not, be configured to operate in the black-out mode, e.g. by default. According to another aspect of the invention there is provided a vehicle display device with an array of light-emitting diodes (LEDs) and a control means operatively connected to the LEDs for displaying operational information relating to the vehicle, the LEDs comprising first LEDs operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in a black-out mode by default, in which it is configured to selectively energise the second LEDs to display the operational information. The control means may, but need not, default or be configured to default in the black-out mode. The control means may be operable to switch, in use, into the visible light mode. The control means may be configured to switch, in use, into the visible light mode when a request or input or command is received, e.g. from a user. The control means may be configured to operate, in use, in an off mode, e.g. in which no power is supplied to either the first LEDs or the second LEDs. The control means may comprise a selector, for example for switching between the black-out and visible light modes. The control means or selector may be operable to switch, e.g. in use, between the back-out mode and the visible light mode via the off mode. The control means or selector may be operable to switch, e.g. in use, from the back-out mode to the visible light mode via the off mode. The control means or selector may be operable to switch, e.g. in use, from the visible light mode to the back-out mode via the off mode. Advantageously, the vehicle display may be maintained, or may be configured to be maintained, in black-out mode, e.g. even upon and / or after start-up of the vehicle. This may be beneficial, for example if the vehicle is started in an environment where the vehicle should remain in a black-out mode. The first LEDs may be inactive in the black-out mode. The control means may be configured to de-energise the first LEDs, or to prevent or inhibit the first LEDs from being energised, in the black-out mode. The second LEDs may be inactive in the visible light mode. The control means may be configured to de-energise the second LEDs, or to prevent or inhibit the second LEDs from being energised, in the visible light mode. The vehicle display device may comprise one or more relays, e.g. for selectively switching between the visible light mode and the black-out mode. In a normal or default position of the one or more relays the second LEDs may be connected to ground or earth, and the first LEDs may be unconnected to or disconnected from ground or earth. The one or more relays may be in a normal or default position in the black-out mode, e.g. in which the second LEDs are connected to ground and / or the first LEDs are disconnected from ground In the visible light mode, the one or more relays may be configured such that the first LEDs are connected to ground or earth, and the second LEDs are unconnected to or disconnected from ground or earth. The one or more relays may be in an activated position in the visible light mode, e.g. in which the first LEDs are connected to ground and / or the second LEDs are disconnected from ground. The vehicle display device may further comprise a battery which is configured to energise the LEDs. At least some of the LEDs or LED pairs may each provide a pixel of a display screen. The vehicle display device may comprise a screen, which may be semi-transparent or translucent, The screen may cover at least partially the array of LEDs or LED pairs. The screen may be partially opaque, semi-opaque or smoked. The LEDs or LED pairs may include one or more indicator lights. The one or more indicator lights may be indicative of a fault or state of one or more operational parameters or components of the vehicle. The vehicle display device may comprise a dimmer, e.g. for adjusting a brightness setting of the first and / or second LEDs. The vehicle display device may comprise a common dimmer for adjusting a brightness setting of each or both of the first and second LEDs. The common dimmer may be comprised in or be a part of, or may communicate with, the control means. The vehicle display device may comprise an offset adjustor. The offset adjustor may be for or suitable for adjusting the brightness setting of the second LEDs relative to that of the first LEDs, e.g. for a given position of the dimmer. The offset adjuster may be comprised in or be a part of, or may communicate with, the control means. The relationship of a brightness of the second LEDs in relation to the first LEDs may be determined, calculated and / or governed by a delta function. The brightness setting of the second LEDs may correspond to that of the first LEDs by a delta function. The delta function may be adjustable, for example via a user input. The vehicle display device may comprise a delta function adjustor. The delta function may be adjusted and / or implemented by the control means. The control means may be operable to convert between units of vehicle measurements, for example between miles and kilometres. The vehicle display device may comprise a conversion input, e.g. for selecting the units of vehicle measurements. The vehicle display device may comprise a display screen. The display screen, e.g. the LEDs or LED pairs, may be configured to display any number of: • a gearbox configuration indicator, for example indicating if the gearbox is in park, reverse, neutral, drive and low gear; • a gear indicator to indicate the current gear number which is engaged in a gearbox; • an engine oil pressure indicator and / or warning light; • an engine temperature indicator and / or warning light; • a water temperature indicator and / or warning light; • a fuel level indicator; • one or more vehicle warning lights; • a battery charge indicator and / or warning light; • a measurement of distance driven by the vehicle; • a speedometer; • an engine revolution speed indicator. The control means may comprise a controller, for example a microcontroller, for controlling the LED pairs to display the operational information. The controller may be connectable to a controller area network (CAN) bus for controlling the LED pairs to display the operational information. According to another aspect of the invention there is provided a vehicle comprising a vehicle display device, e.g. a vehicle display device as described above. According to another aspect of the invention there is provided a vehicle comprising a vehicle display device with an array of light-emitting diode (LED) pairs and a control means operatively connected to the LED pairs for displaying operational information relating to the vehicle, each LED pair comprising a first LED operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in a black-out mode by default, in which it is configured to selectively energise the second LEDs to display the operational information. According to another aspect of the invention there is provided a vehicle comprising a vehicle display device with an array of light-emitting diode (LED) pairs and a control means operatively connected to the LED pairs for displaying operational information relating to the vehicle, each LED pair comprising a first LED operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in a black-out mode by default, in which it is configured to selectively energise the second LEDs to display the operational information. The vehicle may comprise a controller area network (CAN) bus. The CAN bus may be in communication with the control means. The control means may be configured to operate in a visible light mode, in which it is configured to selectively energise the first LEDs to display the operational information. According to another aspect of the invention there is provided a method of operating a vehicle display device, e.g. the vehicle display device described above. The method may comprise energising an array of infrared LEDs or infrared light-LEDs of the vehicle display device, e.g. by default and / or on start-up and / or unlocking of a vehicle within which the vehicle display device is incorporated. The infrared LEDs or infrared light LEDs may be energised to display operational information, e.g. relating to the vehicle. The method may comprise energising the array of infrared LEDs in a black-out mode. The method may comprise energising an array of visible LEDs or visible light-LEDs of the vehicle display device, e.g. after switching out of the black-out mode and / or in response to a request or input or command from a user. The method may comprise switching the vehicle display device from the black-out mode to a visible light mode, e.g. in which an array of visible LEDs or visible light LEDs are energised. The visible LEDs or visible light LEDs may be energised to display operational information. The method may further comprise configuring the control means to operate in black-out mode by default, the control means being operably switchable to the visible light mode. The method may comprise adjusting a brightness setting of at least one or each of the first and second LEDs using a dimmer, e.g. a common dimmer. The method may comprise adjusting the brightness setting of the second LEDs relative to that of the first LEDs for a given position of the common dimmer using an offset adjuster. The brightness setting of the first and / or second LEDs may be determined or calculated using a delta function. The delta function may describe or govern a relationship between a brightness of the second LEDs in relation to the first LEDs. The method may comprise adjusting the delta function, for example via a user input. Any of the aforementioned vehicle display devices may comprise a circuit board. The LED pairs may be arranged on the circuit board. At least some of the LED pairs may each providing a pixel of a display screen. In other words, each pixel of the display may be provided by one of first or second LED of a respective on of the LED pairs. Each pixel may be a self-emitting pixel. The first and second LED of each LED pair may be arranged adjacent one another on the same circuit board. The circuit board may be a printed circuit board. The light emitted by the second LEDs may be visible, for example may only be visible, when a user uses a night vision imaging system (NVIS). The control means of any of the aforementioned vehicle display device may be configured to selectively energise only the second LEDs, for example in the black out mode, to display the operational information. The control means may require a user input to switch into the visible light mode. Any of the aforementioned vehicle display devices may comprise a dot matrix display. At least some of the LED pairs may each provide a pixel of the dot matrix display. One of the first LED and second LED in each LED pair may be selectively energised to display information to the user. Any of the aforementioned vehicle display devices may be an vehicle LED display device. An LED display device may refer to a display device where the pixels are provided by LEDs. For example, no liquid crystals may be present. Any of the aforementioned vehicle display devices may comprise a filter to block any visible light emitted from the second LEDs in the black-out mode. For the avoidance of doubt, any of the features described herein apply equally to any aspect of the invention. For example, the vehicle may comprise any one or more features of the vehicle display device relevant thereto or vice versa. Similarly, the method may comprise any one or more features or steps relevant to one or more features of the vehicle display device or the vehicle. Another aspect of the invention provides a computer program element comprising and / or describing and / or defining a three-dimensional design, e.g. of the vehicle display device described above or an embodiment thereof. The three-dimensional design may be for use with a simulation means or an additive or subtractive manufacturing means, system or device. The computer program element may be for causing, or operable or configured to cause, an additive or subtractive manufacturing means, system or device to manufacture the vehicle display device described above or an embodiment thereof. The computer program element may comprise computer readable program code means for causing an additive or subtractive manufacturing means, system or device to execute a procedure to manufacture the vehicle display device described above or an embodiment thereof. A further aspect of the invention provides a computer program element comprising computer readable program code means for causing a processor to execute a procedure to implement one or more steps of the aforementioned method. A yet further aspect of the invention provides the computer program element embodied on a computer readable medium. A yet further aspect of the invention provides a computer readable medium having a program stored thereon, where the program is arranged to make a computer execute a procedure to implement one or more steps of the aforementioned method. A yet further aspect of the invention provides a control means or control system or controller comprising the aforementioned computer program element or computer readable medium. For purposes of this disclosure, and notwithstanding the above, it is to be understood that any controller(s), control units and / or control modules described herein may each comprise a control unit or computational device having one or more electronic processors. The controller may comprise a single control unit or electronic controller or alternatively different functions of the control of the system or apparatus may be embodied in, or hosted in, different control units or controllers or control modules. As used herein, the terms “control unit” and “controller” will be understood to include both a single control unitor controller and a plurality of control units or controllers collectively operating to provide the required control functionality. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) or control module(s) to implement the control techniques described herein (including the method(s) described herein). The set of instructions may be embedded in one or more electronic processors, or alternatively, may be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present invention is not intended to be limited to any particular arrangement. In any event, the set of instructions described herein may be embedded in a computer-readable storage medium (e.g., a non-transitory storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors / computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information / instructions. Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. For the avoidance of doubt, the terms “may”, “and / or”, “e.g.”, “for example” and any similar term as used herein should be interpreted as non-limiting such that any feature so-described need not be present. Indeed, any combination of optional features is expressly envisaged without departing from the scope of the invention, whether or not these are expressly claimed. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner. Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a schematic of a vehicle display device according to the invention; Figure 2 is a schematic of a vehicle which has a vehicle display device according to Figure 1; Figure 3 is a schematic of the control means of the vehicle display device of Figure 1; Figure 4 is a possible implementation of a relay circuit in the vehicle display device of Figure 1; and Figure 5 is another possible implementation of a relay circuit in the vehicle display device of Figure 1. Referring now to Figure 1, there is shown a vehicle display device 1. The vehicle display device 1 has an array of light-emitting diode (LED) pairs 2. The vehicle display device 1 has a control means 3 which is operatively connected to the LED pairs 2. The LED pairs 2 are configured to display operational information relating to a vehicle in which the vehicle display device 1 is mounted. Each LED pair 2 has a first LED 21 operable to emit visible light and a second LED 22 operable to emit infrared light. The LED pairs 2 are arranged on a common circuit board, with the first and second LED 21, 22 of each LED pair 2 being adjacent one another. Some of the LED pairs 2 are arranged in an LED display screen 11 such that the LED pairs 2 provide pixels of the display screen 11. Each of the first or second LED 21, 22 in each LED pair 2 is selectively energised to display a pixel of the screen 11. In this way, information is conveyed to the user. In this example, the display screen 11 comprises a dot matrix LED display. Each LED pair 2 provides a pixel of the display which directly conveys information to a viewer of the display screen 11. Each pixel is a self-emitting pixel. The display screen 11 is configured to display any number of: • a gearbox configuration indicator, for example indicating if the gearbox is in park, reverse, neutral, drive and low gear; • a gear indicator to indicate the current gear number which is engaged in a gearbox; • an engine oil pressure indicator and / or warning light; • an engine temperature indicator and / or warning light; • a water temperature indicator and / or warning light; • a fuel level indicator; • one or more vehicle warning lights; • a battery charge indicator and / or warning light; • a measurement of distance driven by the vehicle; • a speedometer; • an engine revolution speed indicator. Some others of the LED pairs 2 are arranged to provide indicator lights 12. The indicator lights 12 may be indicative of a fault or state of one or more operational parameters or components of the vehicle, for example providing an indication that a turn signal is active. In this example, the vehicle display device is configured to display vehicle measurements. The control means is operable to convert between units of vehicle measurements, for example between miles and kilometres. Conversion of units is either activated by a user input, or is set in the control means upon production of the vehicle display device, for example to suit the geographical area in which the vehicle display device is to be used. In this example the vehicle display device 1 also has a translucent smoked screen (not shown) which covers the display screen 11. The smoked screen may also cover at least some of the indicator lights 12. The smoked screen enables information presented by the second LEDs 22 to be viewed more clearly, through night-vision eyewear, for example a night vision imaging system (NVIS). In this example the vehicle display device 1 also has a common dimmer D for adjusting a brightness setting of each of the first and second LEDs 21, 22. In this example the common dimmer D is a part of the control means 3 and is in the form of a dial D, but it will be appreciated that the common dimmer D may also, or alternatively, be operated by a slider or automatically controlled, for example by measuring the ambient light levels in the environment around the vehicle display device and adjusting the brightness of the LEDs 21,22 accordingly. The vehicle display device also has an offset adjustor for adjusting the brightness setting of the second LEDs 22 relative to that of the first LEDs 21 fora given position of the common dimmer D. The offset adjustor is implemented by manipulating the dimmer D, in this example by pulling the dimmer D to enable the offset adjustment by rotation of the dimmer D. The brightness setting of the second LEDs 22 corresponds to that of the first LEDs 21 by a delta function. In this example the delta function is adjustable via a user interface. In this example the offset adjustor is a part of the control means 3 and the delta function is implemented by the control means 3. It will be appreciated that the common dimmer D, offset adjustor and delta function may be a part of, or implemented by, a separate means than the control means 3. The control means 3 is configured to operate, in use, in either a visible light mode, in which it is configured to selectively energise the first LEDs 21 to display the operational information, or in a black-out mode, in which it is configured to selectively energise the second LEDs 22 to display the operational information. In this example, the control means 3 is configured to operate in black-out mode by default and is operable to switch to visible light mode. When the display device 1 is started, for example when the vehicle is started or is unlocked, the control means 3 is configured to always operate in black-out mode. This may prevent accidentally starting the display device in the visible light mode. In this example, a user input is required to switch into the visible light mode. This may prevent a fail-safe system, where a risk that the display device 1 is accidentally started in visible light mode is reduced. Switching is performed using a switch S having three positions, a first position B corresponding to the blackout mode, a second position O corresponding to a deactivated, or ‘off’ mode, and a third position V corresponding to the visible mode. Because the first and second LEDs 21, 22 are provided in LED pairs 2, the same operational information is displayed in either black-out mode or in visible light mode, because the control means 3 selects which LED pair 2 to energise to display information, and the mode of operation determines which LED 21, 22 of the LED pair 2 is energised. With reference to Figure 2, the use of the vehicle display device 1, inside of a vehicle V, is described. In use, when the vehicle display device 1 is located in the vehicle V and a user starts the vehicle V, only the second LEDs will be selectively energised to display operational information, and the first LEDs will not be selectively energised. In order to default to the blackout mode, the switch S resets to the first position B every time the vehicle V is turned off. This means that the vehicle V will not be inadvertently started in visible light mode when the vehicle V is located in an environment where visible light mode would be undesirable, for example in a hostile environment and at night. The vehicle display device 1 can continue to be used in black-out mode, in which case users will typically wear night-vision eyewear in order to read the operational information displayed by the vehicle display device 1. Otherwise, the control means 3 may be switched, by the user using the switch S, to visible light mode. However, the user must move the selector of the switch S through the second, off position O, in order to select the third, visible position V. This mitigates a situation where the user might move the selector of the switch S to the third, visible position V from the first, blackout position B inadvertently or accidentally. If the control means 3 is switched to visible light mode, then any currently energised second LEDs 22 are de-energised, and the first LEDs 21 of the respective LED pairs 2 are energised. The first LEDs 21 are then selectively energised or de-energised henceforth, instead of the second LEDs 22. Similarly, if the control means is switched back to black-out mode from visible light mode then the currently energised first LEDs 21 are de-energised and the second LEDs 22 of the respective LED pairs 2 are energised. Again, the second LEDs 22 are selectively deenergised and energised henceforth. More specifically, during use in black-out mode, when operational information changes only the second LEDs 22 are able to be energised. Similarly, during use in visible light mode, when operational information changes only the first LEDs 21 are able to be energised. Referring now to Figure 3, an example of the control means 3 is shown, schematically. In this example the control means 3 has a controller 31, for example a microcontroller, for controlling the LED pairs 2 to display the operational information. The controller 31 also controls the brightness of the LED pairs 2 based upon the common dimmer D, as well as based upon the offset adjuster and the delta function. The controller 31 is in communication with a controller area network CAN bus (not shown) of the vehicle V. The control means 3 also has a power unit 32 for connecting to a power supply, for example a battery, to power the controller 31. The battery is either the vehicle battery or the vehicle display device has a dedicated battery which is recharged from the vehicle battery. The power unit 32 may also power the LED pairs 2, or the LED pairs 2 may be powered from a power source separately. The controller 31 is configurable to control each of the first and second LEDs 21, 22 individually. In black-out mode, the controller 31 only energises second LEDs 22 and in visible light mode the controller 31 only energises first LEDs 21. Referring now to Figure 4 there is shown another embodiment, where similar features to those of the previous embodiment are provided with the same reference numeral with a succeeding prime (‘). In this example the vehicle display device T has a single pole, double throw (SPDT) relay 4’ associated with each LED pair 2’. In this case the pole terminal of each relay is in communication with the control means 3’, a first throw terminal is in communication with the first LED 21’ and a second throw terminal is in communication with the second LED 22’. Each relay 4’ has a normal position wherein the second throw terminal is electrically connected to the pole terminal, such that, when the control means 3’ energises an LED pair 2’ only the second LED 22’ of the LED pair 2’ is energised. When the control means 3’ is switched to visible light mode, the relays 4’ are switched such that the first throw terminal is in electrical communication with the pole terminal, and so, when the control means 3’ energises an LED pair 2’ only the first LED 21 ’ of the LED pair 2’ is energised. To switch back to black-out mode the relays 4’ are switched back to their normal positions such that the second throw terminal is electrically connected to the pole terminal. The relays 4’ are controlled by the control means 3’, either by the controller 31’ of the control means 3’ or via a separate relay controller (not shown). Each relay 4’ has a relay coil (not shown) which is connected to the same power supply that the control means 3’ is connected to, or to an auxiliary power source, and when one of the relay coils is energised the respective relay switch is switched from the second throw terminal to the first throw terminal. It will be appreciated that whilst only one LED pair 2’ and relay 4’ is shown in Figure 4, this is for illustration only, and any number of LED pairs 2’ and associated relays 4’ may be provided. Referring now to Figure 5 there is shown an alternative embodiment to that of Figure 4, for switching between black-out mode and visible light mode, which uses fewer relays. The embodiment of Figure 5 has features which are similar to those of the first embodiment, which are provided with the same reference numeral with a succeeding double prime (“) In this example the control means 3” communicates directly with the LED pairs 2”. If an LED pair 2” is to be energised to display operational information, the control means 3” effectively instructs both LEDs 21”, 22” of the LED pair 2” to be energised. Each LED 21”, 22” is connected to ground VO, which is a voltage reference point. A plurality, or all, or the first LEDs 21” are connected to a first common connection 51” and a plurality, or all, of the second LEDs 22” are connected to a second common connection 52”. Each of the first and second common connection 51”, 52” is connected to a respective first and second throw terminal of a single pole, double throw relay 4”. The pole terminal of the relay 4” is connected to ground VO. The relay 4” has a normal position in which the pole terminal is electrically connected to the second throw terminal, and the relay 4” can be switched such that the pole terminal is connected to the first throw terminal. The control means 3” is operable to switch the relay 4”. This means that the control means 3” defaults to black-out mode, as, in the default position, there is an open circuit between the first LEDs 21” and ground VO. This means that when the control means 3” instructs an LED pair 2” to energise, only the second LED 22” of the LED pair 2” will be energised, as only the second LED 22” has a closed circuit to ground VO. In order to switch to visible light mode, the control means 3” switches the relay 4” such that, when an LED pair 2” is instructed to energise, only the first LED 21” is energised, as the second LED 22” has an open circuit to ground VO. Similarly, when the control means 3” switches back to black-out mode, the relay 4” is switched back and so that the first LEDs 21” have an open circuit to ground VO and so are not energised. This operation may be referred to as “cutting ground”. In this way, black-out mode can be implemented with very few, possibly even just one, relay 4”. This reduces the likelihood of malfunction, and also reduces the complexity of the control meals 3”. Whilst only three LED pairs 2” are shown in Figure 5, this is for illustration only, and any number of LED pairs 2” may be provided. It will be appreciated by those skilled in the art that several variations to the aforementioned embodiments are envisaged without departing from the scope of the invention. For example, the vehicle display device may include LED pairs which are distributed around the vehicle, such as providing indications on the doors or in mirrors. By way of another example, the display device may comprise a filter to block any visible light emitted from the second LEDs in the black-out mode. It will also be appreciated by those skilled in the art that any number of combinations of the aforementioned features and / or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein. The following numbered clauses are provided: Clause 1. A vehicle display device comprising an array of light-emitting diode (LED) pairs and a control means operatively connected to the LED pairs for displaying operational information relating to a vehicle, each LED pair comprising a first LED operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in either a visible light mode, in which it is configured to selectively energise the first LEDs to display the operational information, or in a black-out mode, in which it is configured to selectively energise the second LEDs to display the operational information. Clause 2. A vehicle display device according to clause 1, wherein the control means is configured to operate in the black-out mode by default, and is operable to switch, in use, into the visible light mode. Clause 3. A vehicle display device according to clause 2, wherein the control means comprises a selector operable to switch from the back-out mode to the visible light mode via an off mode, in which no power is supplied to either the first LEDs or the second LEDs. Clause 4. A vehicle display device according to clause 2 or clause 3 comprising one or more relays for selectively switching between the visible light mode and the black-out mode. Clause 5. A vehicle display device according to clause 4, wherein the one or more relays are in a normal or default position in the black-out mode, in which the second LEDs are connected to ground, and the first LEDs are disconnected from ground. Clause 6. A vehicle display device according to clause 4 or clause 5, wherein the one or more relays are in an activated position in the visible light mode, in which the first LEDs are connected to ground, and the second LEDs are disconnected from ground. Clause 7. A vehicle display device according to any one of clause 2 to 6, wherein at least some of the LED pairs each provide a pixel of a display screen. Clause 8. A vehicle display device according to clause 7 comprising a translucent screen at least partially covering the array of LED pairs. Clause 9. A vehicle display device according to any one of clause 2 to 8, wherein the LED pairs include one or more indicator lights indicative of a fault or state of one or more operational parameters or components of the vehicle. Clause 10. A vehicle display device according to any one of clause 2 to 9 comprising a common dimmer for adjusting a brightness setting of both the first and second LEDs. Clause 11. A vehicle display device according to clause 10, comprising an offset adjustor for adjusting the brightness setting of the second LEDs relative to that of the first LEDs for a given position of the common dimmer. Clause 12. A vehicle display device according to any one of clause 2 to 11, wherein the control means is operable to convert between units of vehicle measurements, for example between miles and kilometres. Clause 13. A vehicle display device according to any one of clause 2 to 12 comprising a display screen or a further display screen configured to display any number of: • a gearbox configuration indicator, for example indicating if the gearbox is in park, reverse, neutral, drive and low gear; a gear indicator to indicate the current gear number which is engaged in a gearbox; an engine oil pressure indicator and / or warning light; an engine temperature indicator and / or warning light; a water temperature indicator and / or warning light; a fuel level indicator; one or more vehicle warning lights; a battery charge indicator and / or warning light; a measurement of distance driven by the vehicle; a speedometer; an engine revolution speed indicator. Clause 14. A vehicle comprising a vehicle display device with an array of light-emitting diodes (LEDs) and a control means operatively connected to the LEDs for displaying operational information relating to the vehicle, the LEDs comprising first LEDs operable to emit visible light and a second LED operable to emit infrared light, wherein the control 5 means is configured to operate, in use, in a black-out mode by default, in which it is configured to selectively energise the second LEDs to display the operational information. Clause 15. A method of operating a vehicle display device, the method comprising: energising, in a black-out mode, an array of infrared light-emitting diodes (LEDs) of the io vehicle display device by default and / or on start-up and / or on unlocking of a vehicle within which the vehicle display device is incorporated, thereby to display operational information relating to the vehicle; and switching the vehicle display device from the black-out mode to a visible light mode, in which an array of visible light LEDs are energised to display the operational information.

Claims

1. A vehicle display device comprising:a circuit board;an array of light-emitting diode (LED) pairs arranged on the circuit board, at least some of the LED pairs each providing a pixel of a display screen; and a control means operatively connected to the LED pairs for displaying operational information relating to a vehicle, each LED pair comprising a first LED operable to emit visible light and a second LED operable to emit infrared light;wherein the control means is configured to operate, in use, in either a visible light mode, in which it is configured to selectively energise the first LEDs to display the operational information, or in a black-out mode, in which it is configured to selectively energise only the second LEDs to display the operational information; and wherein the control means is configured to, upon startup of the vehicle display device, always operate in the black-out mode by default, and is operable to switch, in use and after to startup of the vehicle display device, into the visible light mode.

2. A vehicle display device according to claim 1, wherein the control means requires a user input to switch into the visible light mode.

3. A vehicle display device according to claim 1 or claim 2, wherein the pixels are selfemitting pixels.

4. A vehicle display device according to any preceding claim, wherein the control means comprises a selector operable to switch from the back-out mode to the visible light mode via an off mode, in which no power is supplied to either the first LEDs or the second LEDs.

5. A vehicle display device according to any preceding claim, comprising one or more relays for selectively switching between the visible light mode and the black-out mode.

6. A vehicle display device according to claim 5, wherein the one or more relays are in a normal or default position in the black-out mode, in which the second LEDs are connected to ground, and the first LEDs are disconnected from ground.

7. A vehicle display device according to claim 5 or claim 6, wherein the one or more relays are in an activated position in the visible light mode, in which the first LEDs are connected to ground, and the second LEDs are disconnected from ground.

8. A vehicle display device according to any preceding claim comprising a translucent screen at least partially covering the array of LED pairs.

9. A vehicle display device according to any preceding claim, wherein the LED pairs include one or more indicator lights indicative of a fault or state of one or more operational parameters or components of the vehicle.

10. A vehicle display device according to any preceding claim, comprising a common dimmer for adjusting a brightness setting of both the first and second LEDs.

11. A vehicle display device according to claim 10, comprising an offset adjustor for adjusting the brightness setting of the second LEDs relative to that of the first LEDs for a given position of the common dimmer.

12. A vehicle display device according to any preceding claim, wherein the control means is operable to convert between units of vehicle measurements, for example between miles and kilometres.

13. A vehicle display device according to any preceding claim, comprising a display screen or a further display screen configured to display any number of:• a gearbox configuration indicator, for example indicating if the gearbox is in park, reverse, neutral, drive and low gear;• a gear indicator to indicate the current gear number which is engaged in a gearbox;• an engine oil pressure indicator and / or warning light;• an engine temperature indicator and / or warning light;• a water temperature indicator and / or warning light;• a fuel level indicator;• one or more vehicle warning lights;• a battery charge indicator and / or warning light;• a measurement of distance driven by the vehicle;• a speedometer;• an engine revolution speed indicator.

14. A vehicle comprising a vehicle display device with a circuit board, an array of lightemitting diodes (LEDs) arranged on the circuit board, at least some of the LED pairs each providing a pixel of a display screen, and a control means operatively connected to the LEDs for displaying operational information relating to the vehicle, the LEDs comprising first LEDs operable to emit visible light and a second LED operable to emit infrared light, wherein the control means is configured to operate, in use, in a blackout mode by default, in which it is configured to selectively energise only the second LEDs to display the operational information, and wherein the control means is configured to, upon startup of the vehicle display device, always operate in the blackout mode by default, and is operable to switch, in use and after to startup of the vehicle display device, into the visible light mode.

15. A method of operating a vehicle display device, the method comprising:upon startup of the vehicle display device always energising, in a black-out mode, an array of infrared light-emitting diodes (LEDs) of the vehicle display device by default and / or on start-up and / or on unlocking of a vehicle within which the vehicle display device is incorporated, thereby to display operational information relating to the vehicle; andswitching the vehicle display device from the black-out mode to a visible light mode, in which an array of visible light LEDs are energised to display the operational information.

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