TECHNICAL FIELD

The present disclosure relates to a system and method for controlling lighting in an environment. BACKGROUND

US 2016/192461 Al discloses a lighting system in which a user may control a second light source through controlling a first light source. Further a lighting device controller by a sensor is disclosed. A sensor may be a temperature sensor.

Connected lighting refers to a system of one or more luminaires which are controlled not by (or not only by) a traditional wired, electrical on-off or dimmer circuit, but rather by using a data communications protocol via a wired or more often wireless connection, e.g. a wired or wireless network. Typically, the luminaires, or even individual lamps within a luminaire, may each be equipped with a wireless receiver or transceiver for receiving lighting control commands from a lighting control device according to a wireless networking protocol such as ZigBee, Wi-Fi or Bluetooth (and optionally also for sending status reports to the lighting control device using the wireless networking protocol). The lighting control device may take the form of a user terminal, e.g. a portable user terminal such as a smartphone, tablet, laptop or smart watch; or a static user terminal such as a desktop computer or wireless wall-panel. In such cases the lighting control commands may originate from an application running on the user terminal, either based on user inputs provided to the application by the user through a user interface of the user terminal (e.g. a touch screen or point-and-click interface), and/or based on an automatized function of the application. The user equipment may send the lighting control commands to the luminaires directly, or via an intermediate device such as a wireless router, access point or lighting bridge.

Connected lighting systems make lights "smart" by changing their colour, brightness and/or on-state based on one or a combination of inputs from the system. For example, a smart lighting system may be connected to presence sensors so that the luminaries may be switched on and off upon detecting the presence and absence of occupants, respectively. E.g. when a smart lighting system detects that a user arrives at home, it turns on the lights. For standalone lights this is less common, except for lights that change their light setting based on the time of day, or based on a simple motion sensor. More complicated smart lighting systems may include dawn to dusk light sensors for adjusting the brightness of indoor lighting to compensate for the variation of natural light, or they can incorporate a timer for carrying out illumination according to a pre-set lighting schedule.

These connected luminaries are not usually compatible with an existing lighting system and so they often require professional installation. Moreover, once fully installed these prior art automated lighting systems may require substantial effort from the user in setting up a lighting schedule.

JP2009021172A (Toshiba Lighting & Technology) teaches a lighting system where the ambient lighting in an illuminated environment is adapted based on the thermal temperature sensed by an IR image sensor. For example, if the actual instantaneous temperature exceeds a predetermined high temperature threshold, the light source increases the colour temperature and/or reduces the intensity of the emitted light so that a user may perceive a cooler environment. Likewise, if the actual thermal temperature falls below a lower threshold, the light source emits a lower colour temperature and/or a higher light intensity so that the environment may be perceived to be warmer. In a second embodiment, lighting control is based on the monitoring the nasal temperature of an occupant, such that the controlled lighting effects are responsive to the occupant's biorhythm. The system may also infer if an occupant is asleep by monitoring the fluctuation in the occupant's body

temperature, and base thereon implement different light characteristics for encouraging the occupant to fall asleep or to wake up. SUMMARY OF INVENTION

The lighting system provided in JP2009021172A is configured to vary the ambient lighting in an illuminated environment based on instantaneous temperature measurements, in order to change an occupant's perceived temperature in real time.

However, the inventors have recognised that it is not the temperature per se that is determinative of what lighting is most appropriate. E.g the temperature at a specific instantaneous point in time in the morning, could be the same as the temperature at another given instantaneous point in time in the evening, even though in the morning a bright light may be more appropriate whereas in the evening a warmer light is more suitable. Therefore because JP2009021172A's system is only based on the instantaneous temperature it does not always provide the best lighting. Nevertheless, the inventors have recognised that temperature can still be used as a useful indicator if plotted over time. E.g. in the morning the temperature is rising whereas in the evening it is falling, even if at any given moment in the morning the instantaneous temperature may be the same as some instantaneous moment in the evening. Therefore the inventors have recognised that monitoring the temperature over a full cycle of a user's routine (e.g. day, week or month) provides a more accurate

representation of the user's lighting needs.

According to one aspect of the present invention, there is provided an apparatus for controlling ambient lighting in a region occupiable by at least one user, the apparatus comprising:

an interface to at least one lighting unit, wherein said lighting unit is configured to emit the ambient lighting;

an interface to at least one temperature sensor, wherein said at least one temperature sensor is configured to measure ambient temperature in said region and/or another region occupiable by said user, said ambient temperature control varies throughout a predetermined cyclical period; and

a controller configured to:

i) determine a temperature variation cycle based on variations in the measured ambient temperature over one or more instances of said predetermined cyclical period, and therefrom produce a set of lighting instructions corresponding to said temperature variation cycle; and

ii) control the ambient lighting based on the set of lighting instructions.

Optionally, the ambient temperature is at least partially a result of control by the user via a climate controller, and wherein the controller is configured to infer a routine of the user from the determined temperature variation cycle, and based thereon produce the set of lighting instructions.

The fluctuations in temperature over the temperature variation cycle may reflect natural changes in room temperature or may be the result of user activities (e.g.

watching TV or exercising) in a region without climate control, and/or it may be due to a set of climate control instructions being implemented by the climate controller for carrying out climate control in the region. I.e. the temperature variation cycle in the latter case is the result of a climate control cycle implemented by the climate controller, such as a central heating system and/or an air conditioner, in order to cyclically vary ambient temperature in a region.

Said region can be a room local to the ambience control system, or it can include other rooms in the locality of the control system, or it can be another location remote to the control system. The climate control cycle can be a manual setting imputable through the climate controller or it can be a temperature control program.

The predetermined cyclical period may be dependent on the detecting repetitive climate change in a region having no climate control means, e.g. a dawn to dusk temperature variation, or it may be dependent on the duration of climate control cycle if a climate controller is provided. For example, the settings for a domestic heating control are usually based on daily cycles and therefore the cyclical period is taken to be twenty four hours. Some climate control systems base their operation on a weekly schedule and therefore the cyclical period for these systems are accordingly taken to be seven days.

The controller, independent to the climate controller, is configured to reconstruct the climate control cycle from the measured temperature cycle, and bases thereon to characterise the daily routine of a user before producing a lighting instruction suitable for the many different activities undertaken by the user. Note that in embodiments, the measured temperature cycles may be captured from the same region in which the lighting is being controlled, or from another region occupiable by the user, or both.

In some cases, a discrete instance of the apparatus may be provided in each of the plurality of regions occupiable by a user for controlling ambient lighting in their respective regions, Wherein the apparatuses are in communication with each other to produce a set of complementary lighting instructions based on measured temperature cycles in each of the plurality of regions (i.e. the instructions for the different regions as generated so as to complement one another based on the measurement of the temperature cycles from the different regions).

Optionally, the controller is configured to control the ambient lighting by varying one of more light characteristics of the ambient lighting, said one or more light characteristics comprising any one or more of: intensity, colour, colour temperature, illumination pattern and/or direction of light projection. More specifically, intensity refers to the brightness of emitted light.

Optionally, the controller is configured to infer, from the determined climate control cycle, one or more first activity phases of a routine of the user and one or more second activity phases of the routine of said user, and to at least partially base thereon the set of lighting instructions; such that the ambient lighting for the first activity phase is of a higher intensity and/or colour temperature than that for the second phase. The first activity phase may be a wakeup phase suitable for waking an occupant up from sleep, wherein the second activity phase maybe an evening phase suitable for encouraging an occupant to fall asleep.

Optionally, the controller is configured to control the ambient lighting by switching the lighting unit on and off. Optionally, said switching is controlled by a timer or user input.

Optionally, the controller is configured to infer, based on the determined climate control cycle, one or more first occupancy phases when the region is occupied by at least one active user, and to switch on the lighting unit or dim up the ambient lighting during the one or more first occupancy phases; and/or wherein the controller is further configured to infer, based on the determined climate control cycle, one or more second occupancy phases when said region is unoccupied or only occupied by an inactive user, and to switch off the lighting unit or dim down the ambient light during the one or more second occupancy phases. Furthermore, the controller is configured to differentiate, from the determined climate control cycle, whether the region is unoccupied or only occupied by an inactive user.

Optionally, the climate control cycle is predetermined cyclical period is a day, week or month. The controller is configure to automatically switch between day, week or month based on monitoring the deviation between detected climate control cycles.

Optionally, the set of lighting instructions accounts for seasonal variations or variations in location. The variations in location may be on a geographical scale, e.g. the lighting instruction accommodates for deviancy in natural daylight at different geographical locations; or they can be relatively small, e.g. the lighting instruction caters for the different lighting requirements in different parts of the user's home (e.g. bedrooms and living room in a household).

Optionally, the apparatus comprises an interface to detecting means for detecting said seasonal variations, said detecting means comprising at least one of a light sensor, humidity sensor, secondary temperature sensor and/or day counter; and wherein the controller is configured to produce the set of lighting instructions based on the seasonal change as detected by said detecting means; and wherein set of lighting instructions partially based on the seasonal change as detected by said detecting means.

Optionally, the controller is configured to apply a correlation factor to the measured ambient temperature to account for at least a portion of heat dissipated at the lighting unit. The correlation factor may be a pre-determined factor, or it can be calculated from the measured ambient temperature. Optionally, the set of lighting instructions further comprises a user defined lighting schedule.

According to another aspect disclosed herein, there is provided a luminaire that comprises the apparatus and further comprises the lighting unit and the temperature sensor.

According to another aspect disclosed herein, there is provided a lamp for fitting into a luminaire, the lamps comprises the apparatus, and further comprises the lighting unit and the temperature sensor. Optionally, the lamp takes the form of a retrofittable LED- base replacement for a filament bulb.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Fig. 1 is a schematic block diagram of an embodiment of a lighting control system according to the present invention.

Fig. 2 is a flow chart showing the operation of the lighting control system as shown in Figure 1.

Fig. 3a is a perspective view of the lighting control system according to an embodiment of the present invention.

Fig. 3b is a perspective view of the lighting control system according to another embodiment of the present invention.

Fig. 4 is a side view of an environment employing the lighting control system as shown in Figure 3 a and Figure 3b.

Fig. 5a is a typical measured temperature cycle sampled during winter according to an embodiment of the present invention.

Fig. 5b is a typical measured temperature cycle sampled during summer according to an embodiment of the present invention

Fig. 6 is a side view of an environment employing the lighting control system employing a remotely located temperature sensor according to an embodiment of the present invention.

Fig. 7 is a graph illustrating ambient lighting control implemented according to an embodiment of the present invention.

Fig. 8 is a graph illustrating ambient lighting control implemented according to another embodiment of the present invention. Fig. 9 is a graph illustrating ambient lighting control implemented according to yet another embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

It is desirable to provide users of a smart lighting system a system that automatically adapts to their personal daily routine and schedule. Some users may find configuring (or programming) a control system taxing and perplexing, especially if they are required to make frequent adjustments to the lighting schedule, e.g. there are uncertainties in their daily routines, or if they follow different schedules over weekdays and weekends, or if there is a significant seasonal variation throughout the year. Moreover, once they have set up other automated controls in the household, e.g. a HVAC system or home entertainment system, they may not want repeat the same set-up process again. A possible solution can be found in a prior art fully integrated air conditioning and lighting system, where a combined temperature and lighting schedule can be input simultaneously. However such systems can be costly to purchase and complicated to install.

The present invention provides a lighting system where automatic lighting control is based on a user's daily routine deduced from measured temperature cycles. This minimises the need for the user to manually configure or program a lighting schedule corresponding to his/her routine, whilst the resulting light programs are bespoke to each of the individual users. I.e. it does not rely on comparing instantaneous temperature readings against a predetermined threshold, nor dedicated body temperature measurements as taught in prior art lighting systems. Furthermore, because the lighting system can take into account the most updated temperature measurements, the resulting lighting control is able to response to deviations in the user's daily schedule.

Figure 1 illustrates an example of a lighting control system 10 according to embodiments of the present invention. The control system 10 comprises a controller 30 in communication with a temperature sensor 20 and a lighting unit 40. Optionally, the control system 10 may comprise one or more of additional sensors such as day counter 22, ambient light sensor 24 and humidity sensor 26.

The temperature sensor 20 is configured to detect ambient temperature. It can be any temperature sensor known to the person skilled in the art, for example a

thermocouple, thermistor, resistance temperature detector (RTD) or infrared (IR) temperature sensor. Depending on the type of temperature sensor used, the measured temperature referred herein can be based on air temperature, or (in the case of IR sensors) surface temperature of one or more target objects.

The lighting system 40 comprises a light control unit 42 in communication with the controller 30, for controlling the power supply and lighting characteristic of one or more light emitters 44, which in turn based on lighting control commands from the controller 30. The lighting characteristic of the illumination emitted by the emitters 44 includes brightness, flickering frequency, colour temperature, colour rendering index and direction light projection. Each of the one or more light emitters 44 is arranged to contribute to ambient lighting in an environment occupied by one or more occupants. The one or more light emitters 44 may be any emitters suitable for illumination, for example LEDs, incandescent bulbs, halogen lamps, florescence lamps, arc lamps, strobe lights and discharge lamps. There may be multiple light emitters 44 in a lighting system 40, wherein each of the multiple light emitters 44 may be of the same or different types. The light control unit 42 may control the one or more light emitters 44 in the same lighting system 40. And in the case where a lighting system 40 comprises a plurality of light emitters 44, the individual light characteristic from each the plurality of light emitters 44 may be different or synchronised. For example, the light emitters 44 in a given lighting system 40 may comprise two or more LED lamps, each independently modulated and controlled by the same light control unit 42 for emitting light with different colour temperatures.

In general, the controller 30 carries out three basic functions: a) to receive realtime temperature measurement from temperature sensor 20; b) to create a measured temperature cycle from said real-time temperature measurement, and base thereon determine an occupant's daily routine; and c) to produce a set of lighting instructions based on the occupant's daily routine for automatically controlling the ambience lighting emitted by the lighting unit 40. Figure 2 gives an example of the process 200 for carrying out the automated lighting control. The process starts 202 once a user connects the lighting control system 10 to a power supply. The lighting control system 10 then enters an initiation process 210. Since there is no measured temperature cycle available during the initiation phase 210, the controller 30 follows a set of default lighting instruction for controlling the ambience lighting at lighting unit 40. Said default lighting instructions may be constant ambience settings or can be a set of variables based on instantaneous measurements by one or more of the sensors 20,22,24,26.

During the initiation phase 210, the controller continuously records instantaneous temperature measurements captured by the temperature sensors 20, and/or any other measurements from the additional sensors 22,24,26 as they become available. The time history of measured temperature forms the basis of measured temperature cycle. The initiation phase 210 takes up the entire predetermined cyclical period, i.e. a day, a week or a month. As an example, if the predetermined cyclical period is a day, the controller 30 may record the temperature for a complete 24 hour period before progressing onto the next stage, where the controller analyses 220 the measured temperature cycle and therefrom infers an occupant's daily routine.

For example, the controller may recognise 220 a sudden rise in temperature in the measured temperature cycle during a given period (6 a.m.), it then proceeds to match said sudden temperature change against a catalogue of temperature profiles that are typical to different user routines in a pre-defined database. Upon identifying a matching temperature profile it reaches a conclusion that the occupant has woken up and switched on the central heating, causing the sharp temperature rise. Therefore the controller characterises the given period (6 a.m.- 7a.m.) as a "wake-up phase" and specifies a set of lighting instruction that are most suitable for said period, e.g. light characteristics with high intensity and colour temperature for encouraging the occupant to wake up from his/her sleep. Consequently, a complete set of lighting instruction is produced 230 for controlling the ambient lighting throughout the duration of predetermined cyclical period.

In some cases the controller 30 need not fully characterise some of the occupant's daily routine, e.g. due to insufficient data points captured during the initiation process, or if there is a substantial deviation in a user's daily routine. Upon recognising such periods, the controller 30 may temporarily follow the default lighting instruction.

Once a set of lighting instructions is produced, i.e. after the first cyclical period, the lighting system implements 240 the set of lighting instruction in a renewed lighting control cycle. For example, at the onset of detecting a sudden temperature rise at 6a.m. (the "wake-up phase"), the controller realises the occupant has just woken up and so promptly changes the ambient lighting to one with high intensity and colour temperature. In this case the lighting controller 30 does not start until it recognises a rise in measured temperature, i.e. a confirmation where an expected user routine has started. That is, if the occupant wakes up at a later time (or earlier time) the lighting control system may also deviate from the lighting schedule to defer (or bring forward) the required ambient lighting control. In other embodiments, the lighting control may starts automatically according to the lighting instruction, regardless of deviation in measured temperature from the measured temperature cycle.

In some cases, the lighting control system may opt to reuse the set of lighting instructions 250 for the subsequent cyclical periods. Or alternatively it is configured to measure ambient temperature as it implements the prescribed lighting control 240, in order to produce a new daily temperature cycle for updating 260 the existing measured temperature cycle on record. Updating may be carried out by replacing the existing temperature cycle with a newly captured temperature cycle, or it can be done by averaging the newly captured cycle with those captured in preceding days.

Figures 3 a and 3b show an example of the lighting control system, taking the form of a retrofittable LED lamp replacement 10a for a conventional filament bulb. More specifically, said LED lamp 10a is retrofittable to any standard light bulb socket (34) known to the person skilled in the art, for example Bayonet, Edison screw, bi-pole and bi-pin connections. In the particular embodiment a Bayonet fitting 32 is employed, allowing the LED lamp 10a to be fitted onto existing luminaires, e.g. ceiling pedant fittings, ceiling lights and table lamps. In other words, the entire lighting control system is integrated into a standalone LED lamp, or a bulb, connectable onto a standard light fitting. The use of retrofittable bulb replacement 10a provides users with an automated controlled lighting solution without incurring significant installation cost.

The LED lamp replacement 10a comprises a main body 12 for enclosing all of the main components, i.e. controller 30 (not shown), the temperature sensor(s) 20 (not shown), as well as the lighting system. In this particular example the lighting system comprises a light diffuser 46 for mixing the emitted light from a plurality of LEDs 44, each capable of producing different light characteristics. In some embodiments reflectors and/or lens are provided for controlling emitted light distribution and/or direction.

As shown in Fig 3 a, the side of the main body 12 comprises one or more openings 342, e.g. slits, for allowing ambient air circulation or IR radiations from

background objects to be detected at the temperature sensor(s) 20 (not shown) interior to the main body 12. The temperature sensors(s) 20 may alternatively be located on the exterior surface of main body 12. In some embodiments, a plurality of temperature sensors are distributed around the longitudinal axis of the LED lamp so to provide directional temperature measurements. This is particularly useful if multiple retrofittable LED lamp replacements are proximally fitted onto the same luminaire, where an IR sensor may sense an erroneously elevated temperature if it faces an adjacent LED lamp.

In operation, the light emitters 44 and light control unit 42 are expected to generate and dissipate a significant amount of heat, which in turn may affect the accuracy of the temperature measured at the temperature sensors 20 located in their vicinities. Therefore in some embodiments, the measured temperature is adjusted using predetermined correlation factors to compensate for the effect of heating. Alternatively, said correlation factor may be calculated from a temperature measured during a calibration process.

In another embodiment, as shown in Fig. 3b, the lighting control system 10 may take the form of a luminaire 10b. For example, the temperature sensor(s) 20 (and the openings 342), controller 30, as well as the lighting controllers 42 of the lighting system 40, are contained in the base 12b of the luminaire. As a result, said luminaire may be able to provide controlled ambient illumination using off-the-shelf bulbs and LED lamps 44 via standard light bulb fittings 48. In comparison with the embodiment shown in Fig. 3a, this particular embodiment effectively separates the light emitter (bulbs and lamps 44) from the lighting control system 10 so as to reduce capital cost if a large number of light emitters 44 are needed in a given location.

The retro fittable lamp replacement 10a and the luminaire 10b, each containing the entire lighting control system 10 and are capable of controlling ambient lighting in an illuminated environment 100, are shown in Fig.4. The illuminated environment can be any temperature controlled indoor environment 100 such as a living room, a bedroom, an office, restaurant or concert hall suitable to accommodate one or more occupants 100. Temperature control in said environment 100 are achieved using any suitable temperature controlling means, such as heaters, radiators or fireplaces 102 for raising the controlled ambient temperature in the environment 100, or evaporative cooler or air conditioner 104 for lowering said controlled ambient temperature in the environment 100. The illuminated environment 100 can also be any outdoor environments, such as garden, park and stadiums, where temperature controlling means, e.g. patio heaters and spray coolers, are provided to at least partially control the ambient temperature in the presence of occupant(s).

In some cases, the temperature controlling means 102, 104 controls the ambient temperature in accordance to the occupant's setting that is inputted manually into a temperature controller, or it can be based on reactive climate control, i.e. said temperature controller carries out temperature control in response to sensor readouts such as real time presence information and real time temperature measurements. The resulting temperature cycle is expected to deviate significantly on a daily basis. Alternatively, temperature control may be achieved using a pre-defined temperature control program, such as a user specified control schedule inputted manually into a programmable temperature controller, comprising parameters such as operating time and target temperatures. In this case, the resulting temperature cycle is expected to be relatively consistent on a daily basis, even though different temperature cycles can be anticipated across the span of a whole year due to seasonal change.

The instantaneous temperature in the environment may be detected by the temperature sensor 20 and subsequently fed to the controller for creating a history of temperature fluctuation over time. Once sufficient data points are collected for a given period of time the controller analyses the temperature fluctuation within the given period and based thereon characterises the occupancy's activity. As an illustration, the controller captures at least a day's worth of temperature measurements, in order to produce a representative daily temperature cycle as shown in Fig. 5a and Fig. 5b. It will be appreciated that a more accurate statistic may be attained if the temperature cycle is constructed from more sampling points. E.g. each of the data points in a temperature cycle maybe averaged from the corresponding points taken in the preceding days.

The time history, as illustrated in Fig. 5a, represents typical temperature fluctuations as expected in autumn or winter over the course of a day, where the environment 100 is provided with a heater 102 as the temperature controlling means. The time history plot in Fig. 5a shows a sudden hike in measured temperature from 18°C (at 6a.m.) to 22°C (at 7a.m.), and subsequently stays at a constant temperature at 22°C throughout the day. The controller analyses such time history and characterises the period from 6a.m. to 7a.m. as a "wake-up phase". The controller is programmed to recognise and relate the trend as a typical wake up routine of an occupant, e.g. turning on the heating at a set temperature of 22°C.

Similarly, the controller may interpret the steady drop in temperature from 22°C (at 9p.m.) to 18°C (at midnight) as a "bed time phase", as this corresponds to a typical room temperature profile where an occupant turns off heater 102 before putting himself/herself to bed.

Furthermore, the controller is configured to differentiate "wake-up phase" from "bed time phase" by comparing the temperature gradients (dT/dt) during these periods. For example, the "wake-up phase" is more likely to be associated with activating an active temperature control (i.e. temperature controlling means 102, 104 working at full capacity to achieve a

predetermined setpoint) and thus a steep temperature gradient is expected, whereas during the "bed time phase" temperature usually drops (or rises during summer time) relatively slowly though energy dissipation to surroundings and therefore exhibits a shallower temperature gradient. Likewise, the controller recognises a constant (elevated) temperature from 7a.m. to 8p.m. which in turn represents the room is occupied by an active user and labels such period as "regular activities phase".

The controller is configured to recognise the "wake-up phase" and "bed time phase" throughout the year, even though significant difference may be expected in the temperature profiles as a result of seasonal change. The time history in Fig. 5b represents typical temperature fluctuation experienced during summer time, where the environment 100 is provided with an air conditioner 104 as temperature controlling means. In this case the temperature profile mirrors the temperature profile detected during summer time shown in Fig. 5a, i.e. temperature drops sharply from a relatively high temperature of 24°C to 18°C during early morning and stays constantly at 18°C, indicating the occupant wakes up and turns on air conditioning. Based thereon the controller characterises such period as a "wake- up phase". The cycle finishes with a "bed time phase" where the profile exhibits a steady rise in temperature corresponding to the occupant turning off (or down) the air conditioner 104.

As illustrated herein, the controller may base its assessment of occupant's daily routine by monitoring the rate of temperature change, i.e. a sharp temperature gradient indicates a "wake up period", whereas a shallow temperature gradient may be due to ceasing of temperature controlling means 102,104, and thus indicates a "bed time phase". The present invention also provides other mechanisms in order to mitigate the impact of seasonal climate change. In some embodiments, the lighting control system 10 may optionally comprise additional sensors e.g. a day counter 22, ambience sensor 24, hygrometer 26 and/or an additional temperature sensor.

The day counter 22 may be a timer, a digital clock or an electronic calendar that is configured to provide the controller information on the number of temperature cycles elapsed. Upon receiving said information the controller correlates the daily temperature fluctuation to seasonal change and thus permitting a more accurate estimation on user's routine based on measured temperature cycle.

The ambient light sensor 24 may be any light sensors known to the person skilled in the art, for example photodetectors such as charge-coupled devices and

photovoltaic cells. The ambience sensor is configured to detect the amount of natural light and therefrom determine seasonal changes. For example, when a long period of natural daylight is sensed at the ambience sensor 24 it indicates the measurement is taken during a summer period, and so therefore the temperature profile as shown in Fig. 5b is best used to describe the occupant's routine.

The humidity sensor 26 may be any hygrometer known to the person skilled in the art, for example capacity hydrometers, resistive hygrometers and thermal hygrometers. The hygrometer is configured to detect the relative humidity (RH%) and therefrom determine seasonal changes. For example, higher relative humidity are usually expected during the winter months (due to a lower temperature) and therefore upon detecting a high RH% the controller may opt to determine the occupant's routine using the winter temperature profile as shown in Fig. 5a.

The additional temperature sensor differs from the temperature sensor 20 in that it measures external temperature, i.e. it measure the natural temperature external to the temperature controlled environment 100, therefore the measured external temperature is expected to vary throughout the day and the year. The additional temperature sensor may or may not be of the same sensor type as the temperature sensor, or in some cases it may be a networked computer configured to acquire local temperature data from weather services or other resources.

In an alternative embodiment shown in Fig. 6, the lighting control system 10 is connected to a compatible temperature sensor 20b (and/or the other sensors 22, 24 and 26) located remotely to the lighting control system 10c, lOd. For example the temperature sensor may be a plug-in sensor connectable to the mains socket or it may be a standalone sensor. The sensors 20b, 22, 24, 26 may be located proximally to the occupant 110 or anywhere in the environment. In such embodiments the plug-in/standalone sensor 20b may be contained in an enclosure separate to the luminaire 10a or LEDs lamp replacement 10b shown in Figure 2 and Figure 3. In some embodiments, the controller 30 is also provided in the enclosure and so that it controls the lighting unit 40 from a remote location. The use of remotely positioned sensors minimise the impact (e.g. temperature and ambience) of light emitters 44 that may otherwise induced on sensor measurements.

Alternatively, the compatible temperature sensors 20 (and/or the other sensors 22, 24 and 26) may be existing sensors that are commonly built into other compatible control systems, e.g. pre-existing temperature sensors 20 in a HVAC controller or air conditioner, or timer in an electronic clock or computer, or sensor built into an outdoor lighting system. In this case the controller is configured to communicate with said compatible control systems to gather the required sensor data. In some embodiment, the controller is configured to communicate with the HVAC controller or air conditioner to obtain the temperature control program and/or user specified control schedule therefrom, and subsequently characterise occupant's routine directly from said control program and/or control schedule.

In some embodiments, the temperature sensor 20 is located in a remote location occupiable by the occupant that is not part of the ambience controlled environment 100. The remote location may be another room in the some household, or the occupant's office far away. The ambience control system 10 in this case relies on the ambient temperature at said remote location and thus does not detect temperature measurement at the ambience controlled environment 100. For example, automated lighting control may be carried out in a user's bedroom based on the cyclical temperature profile taken in a living room occupiable by the same user. In this case upon turning off the heating in the living room the user retires to bed, triggering the lighting control in the bedroom even though there is no change the ambient temperature in the bedroom.

Alternatively, a temperature sensor 20 may be provided in each of the environment 100 and one or more additional remote location(s), for capturing their respective cyclical temperature profile. As a result the lighting control system 10 may base the lighting control in the environment 100 on a locally measured temperature cycle, as well as those taken at the one or more remote location(s) (outside the environment). This enables the lighting control system 10 to characterise the user's cyclical routine with better precision. For example, by detecting a gentle temperature decline at a user's work place and a subsequent rapid rise in temperature at the user's living room, the control system is able to confirm that the sharp rise in temperature is not due to the user waking up (e.g. also characterised by a sharp temperature rise), but as a result of the user returning home from work.

In some other embodiments, a discreet instance of the control system 10 is provided in each of the controlled environment 100 and one or more remote location(s) occupiable by the same user. Each of the control systems 10 are in communication with each other, via wired or wireless communicating means known to the person skilled in the art. For example, a LED lamp replacement 10a may be installed in each of the rooms in a household to form a lighting control network, and thus enables a synergistic ambience control across the many rooms in the household. I.e., upon detecting a temperature hike in the bedroom and a steady drop in living room temperature, the control system 10 identifies that the user is retiring to bed and therefore modifies the "bed time phase" to include instruction to switch off the illumination in the living room.

For the embodiment shown in Figure 6, the controller 30 is provided with a suitable interface for communicating with each of the temperature sensor 20, lighting system 40, and/or the additional sensor(s) (the timer 22, ambience sensor 24 and humidity sensor 26). The interface with each of the temperature sensor 20, lighting system 40 and/or additional sensor(s) 22,24,26 may comprise any one or more I/O devices for interfacing via any one or more types of signalling medium, and may employ any one or more

communication protocols to do so. For instance, any of the communications between the relevant interface used by the controller 30 and the temperature sensors 20, lighting system 40 and/or additional sensor(s) 22,24,26 may be established by one or more wired connections such as Ethernet, DMX, optical fibre and/or powerline connections, or the communication may be made using wireless communication technology such as infrared or RF based technology, e.g. Bluetooth, Wi-Fi or ZigBee. The wireless communication technology herein refers to a wireless communication protocol plus the necessary capability to transmit and/or receive on a suitable medium over a suitable frequency range and for the technology in question (e.g. a certain RF band or bands). Any of the communications disclosed herein may be established using any one or more of the above-mentioned communications technologies and/or others.

Furthermore, in alternative embodiments to those discussed above, the controller 30 need not necessarily be implemented inside the lamp 10a or luminaire 10b itself. Instead for example the controller 30 may be a central server, desktop computer, laptop computer, tablet, dedicated building control unit, or any other suitable control units. In some embodiments, it may or may not be physically present in the vicinity of the target regions; for example it may control the lighting remotely via a network. Furthermore, the controller 30 may take the form of a central unit or a distributed control function implemented over multiple units. The controller 30 may be implemented in software code stored on a memory (comprising one or more storage devices) and arranged so as when run on a processor (comprising one or more processing units) to perform operations in accordance with the techniques disclosed herein. Alternatively the controller 30 may be implemented in dedicated hardware circuitry, or configurable or reconfigurable circuitry such as a PGA or FPGA, or any combination of software and hardware.

The objective of the present invention is to generate a set of lighting instructions for controlling the ambient lighting, such that appropriate lighting effects may be produced according to the occupant's routine (e.g. daily routine), i.e. it is what the user is doing that matters, not the momentary temperature. As shown in the temperature and lighting profile in Fig. 7 (corresponding to the winter temperature profile in Fig. 5a), the brightness and colour temperature of the emitted light is varied through the day accordingly. For example, once the controller 30 detects a temperature rise in the morning, e.g. at 5a.m., it refers to the "wake-up phase" in the measured temperature cycle and therefrom infer that the occupant(s) are in the process of waking up. The controller then implements a pre-set light characteristic that is suitable for "wake-up phase". For example, the emitted light changes from a dimmer and warmer setting (0.5 lux @ 1700K) to a brighter and cooler setting

(4001ux @ 6500K) over a period of time, e.g. half an hour, so as to provide visual stimulant to the occupant, in order to accelerate the wake up process. Thereafter the emitted light throttles back to a regular setting of 1501ux @ 3000K. Similarly upon detecting a gradual drop in temperature that is characteristic to the "bed time phase", the emitted light gradually reduces from the regular setting of 1501ux @ 3000K to 0.5 lux @ 1700K, which encourages the occupant to fall asleep.

In some cases (not shown), a slight change in light characteristic may be introduced during a period when the temperature in the environment is controlled to a constant set point, e.g. the period 7a.m. to 8p.m. previously labelled as "regular activities phase". For example, according to a predetermined program in a database, the controller may gradually reduce the brightness and colour temperature from 1501ux @ 3000K to 1201ux @ 2500K over the "regular activity phase". More specifically, the light characteristic of the emitted light may be programmed to vary depends upon user's activity.

The brightness and colour temperature settings for the various lighting modes may be pre-defined as factory default settings, or alternatively they can be defined by the user via a suitable user interface (not shown) at the controller 30. The user interface may be provided locally at the controller, or it can be in the form of a remote control device or an application client on a computer or mobile phone connected to the controller via wired or wireless connection (e.g. IR, Bluetooth, WiFi). In some embodiments, a range of settings are pre-defined as factory default settings from which the user may select (e.g. the light characteristic for the "wake-up mode" may be provided as options such as 4001ux @ 6500K and lOOlux @ 2200K), through the user interface, the most preferred setting for him/her.

In some embodiments, the user interface at the controller 30 enables the user to manually control (or override) the lighting control. For example, the user may be able to, at the user interface, switch on and off the lighting unit, or the user may manually program the lighting control, e.g. to extend or shorten the duration of ambience lighting, or to adjust brightness and/or colour temperature, or to specify the delay between onset of detecting a temperature change and implementing lighting control. In some embodiments, upon receiving any manual override or lighting control adjustments inputted by the user at the user interface, the controller 30 amends the lighting schedule to take into account any manual adjustments previously inputted by the user at the user interface.

Figure. 8 illustrates the use of the lighting control system in response to a different scenario. Here as per the occupant's preference, the ambient temperature setting is generally set at a lower set point than that illustrated in Figure. 7, e.g. temperature ranges from 16°C to 20°C throughout the day. A prior art system, which bases its lighting control set point on an absolute room temperatures of 22°C, would work in the environment of Figure 6 but will cease to operate if the ambient temperature does not reach the set point temperature of 22°C. The present system on the other hand, bases lighting control on temperature cycle and thus upon detecting a temperature rise the controller recognise the characterising temperature profile in a "wake-up phase", i.e. sharp rise in temperature followed by a constant temperature at e.g. 20°C, and implements the required bright and cool coloured ambient lighting (e.g. 4001ux @ 6500K).

Furthermore, the temperature gradually reduces shortly after the "wake-up phase". The gradual drop in temperature is similar to that expected during a "bed time phase". The controller refers to the measured temperature cycle and works out that such gradual drop in temperature does not correspond to a "bed time phase", i.e. it takes place shorting after "wake-up phase". Therefore the controller concludes that the occupant is away from home and implements an "out phase" by turning off the ambient lighting. The lighting control system only resumes lighting once a rise in ambient temperature is detected. Again the controller looks up the measured temperature cycle and infers that the sharp rise in temperature does not correspond to a "wake-up phase", but rather it is resuming ambient lighting after a "time out phase". As a result it does not implement the lighting characteristic (4001ux @ 6500K) required in during a "wake-up phase" but instead resumes the regular setting of 1501ux @ 3000K.

Figure 9 gives yet another example illustrating the operation of the ambience control system 10 during summer seasons. In this example, the measured temperature cycle detects cyclical cooling because a sharp drop in temperature is detected. Such sharp drop in temperature is indicative of induced cooling and thus the controller is able to discriminate between summer and winter time. Using a detection and analysis mechanism similar to that shown in Figure 8, the controller recognise the "wake-up phase", "bed time phase" and "out phase" from the measured temperature profile and implements ambient lighting control accordingly. In a different embodiment, the measured temperature cycle as described above may be used to compensate for deviations in a timer-controlled lighting system. For example, the ambience lighting control system 10 further comprises a user interface for manually inputting a set of user-define lighting instruction, e.g. a daily schedule. The controller 30 then follows the user-defined lighting instruction for varying the ambient lighting throughout the day. Due to seasonal change, there may be a shift in a user's daily routine, e.g. due to a longer hours of daylight and warmer weather, the user may stay out later during summer seasons. The controller recognising this gradual change in user's routine through measured temperature cycles as described herein and adjust the user-defined lighting instruction according, i.e. delaying or bringing forward ambient lighting control.

In yet another embodiment, the lighting control system 10 bases temperature measurements in a non-temperature regulated region, i.e. a room without climate control or an outdoor environment. More specifically, the measured temperature cycle in this case captures the daily natural temperature fluctuation (e.g. dawn to dusk fluctuation) and/or the resulting temperature change due to user activities (e.g. temperature rise in a kitchen when the user is preparing a meal). That is, even without recognising abrupt changes in a climate control cycle, the lighting control system 10 is still fully capable of estimating user's routine and based thereon carry out ambient lighting control. For example upon detecting a temperature rise in the morning, e.g. due to sunrise, the lighting control system 10 concludes that the occupant is waking up and implements the "wake-up phase". This user may also specify a delay at the user interface so that the "wake-up phase" lighting sequence is initiated after a pre-set delay. In another case, if the measured temperature in a non-temperature regulated room is higher than an outdoor temperature, the lighting control system 10 recognises that such elevation is caused by occupants' activities and therefore provides an illumination setting suitable for said activities. Similarly, upon detecting a drop in the room temperature (in a living room) in the evening, e.g. due to the occupants retiring to bed or due to a fall in outdoor temperature, the lighting control system 10 implements a "bed time phase". In short, the lighting control system 10 may be able to interpret temperature variation cycles in either indoor or outdoor environment and there from estimate occupants' daily routine, even though no climate control is provided in said environments.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be construed as limiting the scope.