EP1366645A1

EP1366645A1 - Lighting unit

Info

Publication number: EP1366645A1
Application number: EP02701427A
Authority: EP
Inventors: Colin Mitchell
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-28
Filing date: 2002-02-27
Publication date: 2003-12-03
Also published as: WO2002069676A1; WO2002069676A8; GB0104975D0

Abstract

A lighting unit (1) comprises a housing (2) in which are mounted illumination means (3) and an integral remotely controlled switch (4). The illumination means (3) comprises fluorescent tubes and suitable fittings for mounting the tubes. The housing (2) of the lighting unit (1) is adapted for mounting on a wall, ceiling or other such fixture. The remotely controllable switch (4) is capable of receiving a signal from a remote control unit for turning the illumination means on and off.

Description

Lighting Unit

This invention relates to a lighting unit and, in particular, to a remotely controlled lighting unit and a system for providing lighting in a domestic or commercial space.

Lighting units are commonly mounted in the ceiling, walls or other fixtures of domestic and commercial spaces, such as houses, warehouses, factories, industrial sites or office buildings. Such lighting units are usually controlled (i.e. turned on and off) by switching units that are mounted in locations conveniently within reach of users, such as by doorways and the like. Conventional switching units generally comprise straightforward electrical switches connected on the same electrical supply circuit as the lighting units such that the switching unit can be operated to interrupt or connect the power supply to the light unit as desired.

From time to time supplemental or alternative controls may be provided for switching such lighting units. For example, multiple switching units may be mounted in different locations to control a single lighting unit, such as in a stairwell. In another example, a switching unit may comprise a remotely controlled sensor (i.e. a sensor that responds to wireless control transmissions) , and a remote control unit may operate the remotely controlled sensor (e.g. by radio or infra-red) to switch a lighting unit on or off. This allows a user to switch a lighting unit from any location within range of the transmissions from the remote control unit to the remotely controlled sensor. Thus, a user may control lighting units in a house, for example, in a way similar to the way in which a remote control unit for a television is used. Such lighting units and switching units are generally located in separate locations. Installation of the lighting units and switching units generally therefore requires the laying of wiring for power supply to the lighting units, along with additional wiring to the location of the switching unit or units for providing control of the lighting units.

In a domestic space, where rooms and internal fixtures are likely to be relatively permanent, the amount of wiring required to install lighting units and switching units may only cause a certain degree of inconvenience when wires are first laid for the lighting units and switching units. However, in commercial spaces, partitioning of work spaces or floor layouts is a relatively frequent occurrence and the rewiring of lighting units and switching units can therefore cause a great deal of inconvenience.

Lighting units having integral or adjacent switching units may be used to reduce the amount of wiring required to install the lighting units. However, such lighting units must be installed in locations within reach of a user in order that the integral or adjacent switching unit can be operated by the user. Thus, such lighting units are generally only of use in limited situations, such as for wall lights in domestic situations. In particular, these lighting units are not suitable for use in commercial spaces, such as offices or warehouses, especially if these spaces require lighting units to be installed in high or inaccessible positions, such as on ceilings.

According to a first aspect of the present invention there is therefore provided a system for providing lighting in a domestic or commercial space, the system comprising: one or more mountable lighting units each having illumination means and an integral remotely controllable switch; and a remote control unit for controlling the remotely controlled switch of the lighting unit.

Also, according to a second aspect of the present invention there is provided a mountable lighting unit having illumination means and an integral remotely controllable switch.

Thus, in the present invention a lighting unit houses both an illumination means, such as a light bulb, fluorescent tube or the like, and a remotely controllable switch for the illumination means. The lighting unit and switch may therefore be installed with only a single set of wires for providing a power supply to the lighting unit via its integral remotely controllable switch. No separate switching unit or wires to such a switching unit are necessary. Thus, installation of the lighting unit is cheaper and more straightforward than where both a lighting unit and a switching unit must be installed.

Likewise, where it is desired to change the position of the lighting unit of the invention from time to time, such as on rearranging office or industrial spaces for example, it is only required to move the lighting unit and the wiring for power supply thereto, rather than also move and rewire a switching unit. This again significantly reduces the cost of rearranging an office or industrial space.

In the context of this invention, "remotely controllable" is intended to refer to "wireless" or "over the air" control. In other words, the remotely controllable switch will be a switch capable of receiving "wireless" control signals. Likewise, the remote control unit should be adapted to transmit "wireless" control signals to the remotely controllable switch. The control signals sent over the wireless communications link, could be, for example, radio, infrared or ultrasound signals.

The remotely controllable switch may be controlled by the remote control unit as desired. For example the remotely controllable switch may be controlled to switch the illumination means on or off. Alternatively, the remotely controllable switch may be controlled to vary the light output of the illumination means (i.e. "dim" the illumination means) , for example by varying the current to the illumination means (where it is, e.g., a conventional filament bulb) .

The remotely controlled switching may be carried out from any position within the range of communications link between the remote control unit and the remotely controllable switch, as it is simply required that the remotely controllable switch receives an appropriate signal from the remote control unit. The present invention therefore has the additional advantage that the switch can be operated from any position convenient to a user, provided that position is within the range of the remote control unit. Thus, the lighting units of the present invention can be mounted in any position, including positions inaccessible to or out of reach of a user, such as on high ceilings. Thus, not only is the amount of wiring required to install the lighting system reduced, but the system provides greater flexibility in the choice of positioning of the lighting units. The present invention should be contrasted with security lights and such like which may be switched on or off by infrared sensors or the like mounted in proximity to the light itself. Such sensors may respond to movement or heat detected in a given area but do not respond to a signal from a remote control unit. The light is not therefore selectively switched on or off, but rather switched on or off in response to an environmental change. The light or switching unit is not therefore "remotely controllable" . Nevertheless, the remote control unit of the present invention may transmit infrared signals to the remotely controllable switch of the lighting unit. Thus, the remote control unit may comprise an infrared transmitter, and the remotely controllable switch may include an infrared sensor.

Any other suitable medium may alternatively be used to transmit signals between the remote control unit and the remotely controllable switch (and the remote control unit may thus comprise any suitable transmitter and the remotely controlled switch may include any suitable sensor) . Particular communications mediums that are suitable may be radio transmission or ultra-sonic transmission .

Various signals may be sent by the remote control unit transmitter to the switch sensor to control the lighting unit, as desired. Thus, the remote control unit is preferably capable of sending various different signals and the switch capable of responding selectively to different control signals.

The different control signals sent by the remote control unit (transmitter) may be distinguished as desired. For example, infrared signals may comprise pulses or "flashes" of infrared light (emitted by an infrared light emitting diode for example) and/or infrared light modulated at different frequencies or transmitting a digital code. Alternatively, an ultra- sonic or radio signal may be modulated to transmit an analogue or digital code, for example by amplitude or frequency modulation.

Various codes and combinations of signals may be used to control the remotely controllable switch. However, in a particularly preferred embodiment, the remote control unit can send only two different signals. A first signal may constitute an "on" signal and a second signal may constitute an "off" signal. Alternatively, the first signal may constitute a "brighter" signal and the second signal may constitute a "dimmer" signal. These signals might, for example, simply be two signals of different frequency. Alternatively, the first may comprise infrared radiation modulated at a first frequency and the second signal may comprise infrared radiation modulated at a second frequency. The sending of only two different signals is a particularly simple embodiment of the invention to implement, keeping costs to a minimum.

In this embodiment the remote control unit may be pointed at the lighting unit and, when the first or "on" signal is transmitted, the sensor of the lighting unit receives the transmitted signal and causes the illumination means to be switched on. Likewise, when the sensor receives the second or "off" signal, the illumination means may be turned off.

Whilst, in a large room, plural lighting units may be provided, it is desirable that the remote control unit can control (e.g. turn on and off) the lighting units individually. Thus, plural remote control units that transmit signals unique to individual lighting units may be provided. However, it is more convenient to provide a single remote control unit capable of selectively controlling (e.g. turning on and off) one or more of plural lighting units.

In a particularly preferred embodiment, the transmitter of remote control unit therefore has means for transmitting its control signals to different lighting units selectively such that they can be controlled separately. This, in itself, is considered to be a departure from the prior art and, according to a third aspect of the present invention there is therefore provided a remote control unit for separately controlling one or more of plural controllable units by transmitting the same one or more signals selectively to the one or more remotely controllable units.

The selective transmitting of signals to different units can be achieved as desired, depending on the communications arrangement being used. For example, in an infrared system, a lens may be provided in front of the infrared light emitting diode such that the remote control unit only transmits a narrow infrared beam, such as a beam diverging only by around 2° to 3°. Such a remote control unit may then be pointed at individual lighting units and, as the remote control unit transmits a narrow beam of infrared radiation, only the lighting unit at which the remote control unit is pointed will receive the transmitted signals.

In another such embodiment, the remote control unit can be arranged to send multiple signals, each, or some, of which are specific to a particular lighting unit only. For example, the sensor of each lighting unit may be adapted to switch the illumination means on or off only in response to particular signals, e.g. signals of a particular frequency or transmitting a particular digital code. For example, each lighting unit could have its own unique on (or off), etc., signal.

Alternatively or additionally, the lighting units could be controlled by first sending an identity signal for a particular lighting unit and subsequently sending a control signal (e.g. on or off signal), preferably within a predetermined time period after the identity signal is sent. In this case the identity signals could be unique for each lighting unit, but the control signals generic (or at least understood by plural lighting units) . In this arrangement, the lighting unit may be programmed to store its identity signal, and appropriate lighting control signals (such as "on" and "off" signals) . Thereafter, whenever the set identity signal is received, the lighting unit should "listen" for a control signal (such as an "on" or "off" signal) , preferably for a predetermined time only.

In a preferred embodiment, a single remote control unit can address or control plural lighting units or groups of lighting units together or simultaneously.

For example, a broader infrared beam, radio, or ultrasound signal could be used to address plural lighting units simultaneously. In that case the lighting units should be responsive to the same, generic command signals.

Most preferably, a single remote control unit can selectively address single lighting units or plural lighting units (preferably simultaneously). This can be achieved e.g. by providing wider and narrower transmission beams and/or by sending control signals unique to an individual lighting unit or common to plural lighting units.

The lighting units or the switches of the lighting units, may be pre-programmed to be controlled by certain signals. However, it is preferable that the remotely controlled switch and/or remote control unit is/are programmable such that the lighting unit can be programmed in use to be controlled by selected signals . The control signals for a given lighting unit may then be selected by a user, for example such that particular lighting units or groups of lighting units can be controlled by the same or particular signals. Thus, in a preferred embodiment, each lighting unit has a memory for storing the particular control signals it is to be responsive to that can be written to by a user. Preferably the switch of the lighting unit is programmable in this way by the or a remote control unit.

These arrangements can be used to program the lighting units as desired. For example, the remote control unit could be used to program the remotely controlled switch to switch the illumination means of the lighting unit with which it is associated on or off (or brighter or dimmer) in response to a particular signal from the remote control unit. For example, the remote control unit may send a specific signal to the sensor followed by a set signal instructing the memory to store that signal as an "on" signal. Subsequently, when the sensor receives the programmed "on" signal, the switch turns the illumination means with which it is associated on. An "off" signal may be programmed in an analogous way. Equally, a lighting unit could be programmed with particular identity and control signals. In a preferred such arrangement a narrower transmission beam may be used to program or control individual lighting units, and a broader beam used to control groups of plural lighting units.

The remote control unit is preferably programmable so as to be able to address or control groups of plural lighting units together or simultaneously. Thus, the remote control unit may have a memory for storing groups of signals to be sent together on receipt of one (or a reduced number of) user command (s) . The methods and apparatus in accordance with the present invention may be implemented at least partially using software e.g. computer programs. It will thus be seen that when viewed from further aspects the present invention provides computer software specifically adapted to carry out the methods hereinabove described when installed on data processing means, and a computer program element comprising computer software code portions for performing the methods hereinabove described when the program element is run on data processing means. The invention also extends to a computer software carrier comprising such software which when used to operate a lighting system, lighting unit or remote control unit comprising data processing means causes in conjunction with said data processing means said system to carry out the steps of the methods of the present invention. Such a computer software carrier could be a physical storage medium such as a ROM chip, CD ROM or disk, or could be a signal such as an electronic signal over wires, an optical signal or a radio signal such as to a satellite or the like.

It will further be appreciated that not all steps of the invention need be carried out by computer software and thus from a further broad aspect the present invention provides computer software and such software installed on a computer software carrier for carrying out at least one of the steps of the methods set out hereinabove.

Preferred embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:

Figure 1 is an illustration of a lighting unit in accordance with the present invention;

Figure 2 is an illustration of a remotely controlled switch for the lighting unit of Figure 1;

Figure 3 is a front view of a remote control unit in accordance with the present invention; Figure 4 is a rear view of the remote control unit of Figure 3 ;

Figure 5 is a front view of a programmable remote control unit in accordance with the present invention; and Figure 6 is a rear view of the programmable remote control unit of Figure 5.

Referring to Figure 1, a lighting unit 1 comprises a housing 2 in which are mounted illumination means 3 and a remotely controllable switch 4. In this example, the illumination means 3 comprise fluorescent tubes and suitable fittings for mounting the tubes. In other examples, the illumination means could comprise conventional filament or halogen bulbs and appropriate fittings . The housing 2 of the lighting unit 1 is adapted for mounting on a wall, ceiling or other such fixture. In one example, the lighting unit is therefore provided with mounting means. The mounting means might comprise holes in the housing 2 for receiving mounting screws or bolts. In another example, the housing 2 has a shape suitable for mounting in a predefined space of a hung ceiling system. Such ceilings, in which, for example, lighting units or ceiling tiles may be interchanged as desired are common in offices, where the lighting unit 1 of the invention has particular utility.

Referring to Figure 2, the remotely controllable switch 4 of the lighting unit comprises input terminals 5a to 5c for connection to the ring circuit power supply of a building or the like, output terminals 6a to 6c for connection to the illumination means 3 and an electronic switch and sensor 7. Terminal 5a of the switch 4 is connected, in use, to the live wire of the power supply. Likewise, terminals 5b and 5c are connected to a neutral wire and an earth wire respectively. Each of the input terminals 5a to 5c is connected to a respective output terminal 6a to 6c. Thus, output terminal 6a is the live terminal, output terminal 6b is the neutral terminal and output terminal 6c is the earth terminal. The output terminals 6a to 6c are connected to the appropriate terminals of the illumination means 3.

The switch of the electronic switch and sensor 7 is connected so as to be able to connect and disconnect the live connection between input terminal 5a and output terminal 6a and thus turn the fluorescent tube on or off. In another example, the switch may be arranged to vary the power supply to the illumination means 3 and hence "dim" or "brighten" the illumination means 3. It will, of course, be appreciated that in such an example the illumination means 3 should comprise a suitable bulb.

The sensor of the electronic switch and sensor unit 7 is capable of receiving a signal from a remote control unit 8 and electronically switching the switch of the unit 7. In one example, the remote control unit 8 transmits infrared signals and the sensor is a photodiode sensitive to infrared radiation. In another example, the remote control unit transmits ultra-sonic signals and the sensor is a microphone. The switching of the electronic switch and sensor 7 is therefore controlled, for example by infrared or ultra-sonic signals, using the remote control unit 8. Other types of transmission, such as radio transmission for example, are also suitable. A first embodiment of the remote control unit 8 is illustrated in Figures 3 and 4, in which the remote control unit 8 comprises an infrared transmitter. In this example, the remote control unit has an infrared light emitting diode (LED) . The LED is arranged so as to emit a narrow beam of infrared radiation. In this example, the LED therefore has a lens provided in front of it to restrict the width of the transmitted beam such that it only diverges by around 2° to 3°.

The LED is connected to a circuit comprising a power supply, power indication means 11 and two user operable switches 9, 10. The circuit is arranged such that closing a first switch, the "on" switch 9, causes the LED to transmit an "on" signal, in this example by emitting infrared radiation amplitude modulated (i.e. "flashing" or "pulsed") at a first frequency.

Similarly, closing the second switch, the "off" switch 10, causes the LED to transmit an "off" signal, in this example by emitting infrared radiation amplitude modulated at a second frequency. In other examples, the "on" and "off" signals may, of course, be provided by pulsing or modulating the infrared radiation in any suitable way, such as to transmit a digital signal.

This remote control unit 8 is suitable for operating a simple electronic switch and sensor unit 7. The sensor of such an electronic switch and sensor unit 7 transmits a first electronic signal to the switch on receipt the "on" signal from the remote control unit 8 (i.e. infrared radiation modulated at the first frequency) and a second electronic signal on receipt of the "off" signal from the remote control unit 8 (i.e. infrared radiation modulated at the second frequency) . The switch of the electronic switch and sensor 7 is arranged to connect the illumination means 3 to the power supply when it receives the first electronic signal from the sensor and disconnect the illumination means 3 from the power supply when it receives the second electronic signal from the sensor. Thus, the remote control sensor 8 can cause the electronic switch and sensor unit 7 to turn the illumination means 3 on or off. An alternative arrangement allows the illumination means 3 to be brightened or dimmed. Where a room has been provided with plural lighting units 1 the remote control unit 8 can be used to switch the various lighting units 1 on and off individually. The narrow beam of infrared radiation ensures that only the lighting unit 1 at which the remote control is pointed receives the infrared "on" or "off" signal and is therefore switched on or off. Thus, the lighting units may be selectively turned on or off by the controller 8.

A second embodiment of the remote control unit 8 is illustrated in figures 5 and 6. This more complex remote control unit has a similar "on" switch 9, "off" switch 10 and power OK illumination 11. However, the more complex remote control unit 8 additionally has a numeric keypad 13, a set button 14, a memory button 15, comma button 16 and clear button 17. This remote control unit 8 is arranged to transmit different signals according to which buttons of the numeric keypad 13 are operated.

In one example, operating the button corresponding to numeral "1" followed by the "on" switch causes a first "on" signal to be transmitted and operating the button corresponding to numeral "2" followed by the "on" button causes a second "on" signal to be transmitted, etc. The first and second (etc.) "on" signals switch different lighting units 1 on. The lighting units 1 can be switched off in a similar manner.

In another example, operating the button corresponding to numeral "1" causes a first identification signal to be transmitted and operating the button corresponding to numeral "2" causes a second identification signal to be transmitted, etc. These signals can be followed by "on" signals or "off" signals, as desired, to switch lighting units identified by the identification signals on or off.

The more complex remote control unit 8 is designed for operation with a programmable electronic switch and sensor unit 7. This programmable electronic switch and sensor unit 7 has a memory unit (not shown) for storing different signals in response to which it is to turn the lighting unit 1 on or off (or, in the second of the above examples, an identification signal with which the electronic switch and sensor unit 7 is addressed or identified) . The remote control unit 8 of this example therefore has two LEDs, the first of which transmits a narrow infra-red beam which can be directed at a particular lighting unit 7 to program the memory unit of that lighting unit 7 and the second of which transmits a wide beam that allows lighting units 7 to be switched on and off from as large a variety of positions as possible. A lighting unit 7 is therefore programmed by standing close to it and pointing the beam of the remote control unit 8 directly at the lighting unit 7, but can be switched on or off from anywhere within range of the beam of the second LED. Where the remote control unit transmits signals by ultrasound, the signals that are sent to program the lighting unit 7 are transmitted with reduced power compared to other signals for the same reasons .

The more complex remote control unit 8 is normally used to program a more complex electronic switch and sensor units 7 when a room is provided with plural lighting units 1 having programmable electronic switch and sensor units 7. For example, a first lighting unit 1 is programmed with an "on" signal corresponding to "1" on the numeric keypad 13 by depressing the button corresponding to "1" on the numeric keypad 13, followed by the "on" button 9 and the "set" button 14. The memory unit of the lighting unit 1 then stores the "on" signal corresponding to "1" on the numeric keypad 13 of the remote control unit 8 and, when this signal is subsequently received, the lighting unit is switched on. An off signal is programmed in an analogous manner, and lighting units are thus assigned to different numerals of the numeric keypad 13.

In the second example described above, a first lighting unit 1 is programmed with an identity corresponding to "1" on the numeric keypad 13. To do this, remote control sensor 8 is pointed as the desired lighting unit 1 and the numeric keypad button "1" is depressed. Following this, the set button 14 is depressed. The electronic switch and sensor unit 7 receives an infrared signal corresponding to the numeric keypad button 1 and a signal indicating that this signal should be stored in the memory unit. Subsequently, when the lighting unit 1 receives any signal from the remote control unit 8, it compares the signal with that stored in the memory unit and, should the signals match, the electronic switch and sensor unit 7 operates for a pre- determined time.

Thus, when a user depresses the numeric keypad button 1 followed by the on switch 9, the electronic switch and sensor unit 7 for the lighting unit 1 identified as unit 1 first comes into operation and then receives an on signal instructing it to turn on the illumination means 3. Similarly, when a user presses the numeric keypad button 1 followed by the off switch 10, the electronic switch and sensor unit 7 comes into operation and receives an instruction to turn the illumination means 3 off.

Any number of lighting units 1 may be programmed with an identification number using the numeric keypads 13 and the set button 14, as described above. These lighting units 1 can then be turned on and off individually by first depressing the appropriate numeric key pad button followed by the on or off button 9, 10 as appropriate .

To simplify the switching of plural lighting units 1, the memory button 15 can be used to group a number of lighting units 1 in the remote control unit 8. For example, the numeric keypad is used to input a series of numbers separated by the comma button 16, such as "1, 3, 7, 20 and 22" followed by the memory button 15 and a numeral, e.g. 7. Then, on depressing the memory button 15 followed by the numeric key pad button, the signals for lighting units "1, 3, 7, 20 and 22" will be recalled and transmitted. On subsequent depression of the on button 9 or off button 10, this group of lights may then be turned on or off. This is useful where it is desired to create groups of lighting units for a particular room or area of an office or commercial space such that these groups of lights can be turned on or off together. The remote control units 8 are provided with a rechargeable battery having electrical connections on the rear surface of the unit 8 such that, when the remote control unit 8 is placed in a holder (not shown) , these electrical contacts co-operate with reciprocal electrical contacts on the holder. The holder is attached to a power supply, such as the mains ring circuit of a building, and the rechargeable battery of the remote control units 8 is recharged whilst in the holder.

The power OK indicator 11 is illuminated when the battery is sufficiently charged for normal operation of the unit 8. Thus, if the power OK indicator dims or fails to illuminate, a user knows that the battery needs recharging (i.e. that the unit 8 should be placed in its holder) .

In another preferred embodiment of the present invention, radio transmission is used to control the lighting units. In this embodiment, low power radio frequencies of 433 MHz are suitable for transmission, with each transmitter/receiver system using a unique 5-bit code to stop interference with other systems nearby. Each transmitted bit is preferably encoded as a 32-bit stream to resist transmission interference. A suitable remote control unit transmitter microcontroller is a PIC16F873 with a 24 x 2 LCD display and 16 button keypad. The transmitter chip can be, for example, a

AM-HRR3-433 chip. The remotely controllable switch in the lighting unit can use as a receiver a PIC16F84 microcontroller and a AM-RT4-433 chip for receiving. The software for the remote control and switch is preferably written in assembly code language.

Claims

1. A system for providing lighting in a domestic or commercial space, the system comprising: one or more mountable lighting units each having illumination means and an integral remotely controllable switch; and a remote control unit for controlling the remotely controlled switch of the lighting unit.

2. The system of claim 1, wherein the control signals for the switch of the or each lighting unit are transmitted over a wireless communications link, such as by radio, infrared or ultrasound.

3. The system of claim 1, or 2 , wherein the remotely controllable switch of the or each lighting unit may be controlled to switch the illumination means on or off.

4. The system of claim 1, 2 or 3, wherein the remotely controllable switch of the or each lighting unit may be controlled to vary the light output of the illumination means .

5. The system of any one of the preceding claims, wherein the remote control unit is capable of selectively controlling a single lighting unit.

6. The system of any one of the preceding claims, wherein the remote control unit comprises means for transmitting control signals to different lighting units selectively.

7. The system of any one of the preceding claims, wherein the remote control unit can transmit a narrow transmission beam that diverges by around 2° to 3° only.

8. The system of any one of the preceding claims, wherein the remote control unit can selectively transmit a broader transmission beam or a narrower transmission beam.

9. The system of any one of the preceding claims, wherein the remote control unit can transmit multiple different signals, each, or some, of which are specific to a given particular lighting unit.

10. The system of any one of the preceding claims, wherein the remotely controlled switch of a or of each lighting unit is programmable in use such that a lighting unit can be controlled by different selected signals.

11. The system of claim 10, wherein the remote control unit can be used to program the remotely controlled switch of a or each lighting unit.

12. The system of any one of the preceding claims, wherein the or each lighting unit has a user-alterable memory for storing control signals it is to be responsive to.

13. The system of any one of the preceding claims, wherein a group of plural lighting units can be controlled by the same particular control signals.

14. The system of any one of the preceding claims, wherein the remote control unit is capable of controlling a group of plural lighting units simultaneously.

15. The system of any one of the preceding claims, wherein a or each lighting unit has a particular identity and the lighting unit or units are controlled by first transmitting a signal containing the relevant lighting unit or units' identity or identities and then transmitting an illumination control signal to the lighting unit or units within a predetermined time period thereafter.

16. The system of any one of the preceding claims, wherein the remote control unit can send only two different signals.

17. A mountable lighting unit having illumination means and an integral remotely controllable switch.

18. The lighting unit of claim 17, wherein the remotely controllable switch may be controlled to switch the illumination means on or off.

19. The lighting unit of claim 17 or 18, wherein the remotely controllable switch may be controlled to vary the light output of the illumination means.

20. The lighting unit of any one of claims 17 to 19, wherein the remotely controlled switch of the lighting unit is programmable in use .

21. The lighting unit of any one of claims 17 to 20, wherein the lighting unit has a user-alterable memory for storing control signals it is to be responsive to.

22. A remote control unit for separately controlling one or more of plural controllable units by transmitting the same one or more signals selectively to the one or more remotely controllable units.

23. The remote control unit of claim 22, wherein the remote control unit is capable of selectively controlling a single remotely controllable unit.

24. The remote control unit of claim 22 or 23, wherein the remote control unit comprises means for transmitting control signals to different remotely controllable units selectively.

25. The remote control unit of claim 22, 23 or 24, wherein the remote control unit can transmit a narrow transmission beam that diverges by around 2° to 3° only.

26. The remote control unit of any one of claims 22 to

25, wherein the remote control unit can selectively transmit a broader transmission beam or a narrower transmission beam.

27. The remote control unit of any one of claims 22 to

26, wherein the remote control unit can transmit multiple different signals, each, or some, of which are specific to a given particular remotely controllable unit .

28. The remote control unit of any one of claims 22 to

27, wherein the remote control unit can send only two different signals.

29. A system for providing lighting in a domestic or commercial space substantially as hereinbefore described with reference to any one of the accompanying drawings .

30. A lighting unit substantially as hereinbefore described with reference to any one of the accompanying drawings .

31. A remote control unit substantially as hereinbefore described with reference to any one of the accompanying drawings.