Wireless color temperature sensor module with direction indicator unit for outputting a direction indicator signal and lighting system with such a color temperature sensor module

Abstract

Color temperature sensor module (1) with: - a light sensor (2) with a detection area (3) designed to receive light, wherein the light sensor (2) is capable of emitting detection signals to - a processing unit (4), wherein the processing unit (4) is capable of calculating a color temperature value and optionally also an intensity of the light received by the detection area (3) on the basis of the detection signals received by the light sensor (2) and outputting corresponding information, - an energy source (7) designed to supply electrical power to the light sensor (2) and the processing unit (4), and - a transmission unit (5) designed to transmit information representing the calculated color temperature value by using a wireless interface (6), wherein the color temperature sensor module (1) comprises a direction indicator unit (10) designed to output a direction indicator signal to the processing unit (4), and wherein the direction indicator signal is designed to indicate a spatial direction in which the detection area (3) of the light sensor (2) is directed.

Description

The invention relates to a wireless color temperature sensor module or CCT sensor module (CCT= Cor Color Temperature / Correlated Color Temperature), and more particularly to a sensor module capable of detecting light and determining a color temperature, a light color and / or an intensity of the received light and outputting corresponding information.In buildings in particular, control of the colour temperature of the light emitted by lighting fixtures is an important aspect and has an influence on the appearance of objects in buildings and on the sensation of people inside the building. In particular, if no natural light is present or only partially present in regions of the building, illumination that adapts to or compensates for the natural or ambient light outside the building is advantageous for perception inside the building.By way of example, the document DE 10 2012 108235 A1 discloses an illumination device and a method for controlling the same, with the aim that a user feels comfortable in an area illuminated with artificial light and in particular when transitioning from an area illuminated by daylight to an area illuminated with artificial light.It is thus an object of the invention to provide a lighting system that adapts to or compensates for the lack of natural light by employing lighting fixtures installed in the building. However, in order to match the artificial light inside the building to the natural light outside the building, sensors are required to retrieve information about the natural light. These sensors cannot be incorporated into the lighting fixtures because artificial light would distort the light measurements because the artificial light would also be measured.While the luminaires can adapt themselves to particular configurations that can be pre-configured in the luminaires or that can be set by a central control unit to which the luminaires are connected, their adaptation still needs to be based on the same data to ensure that an adaptation of the artificial light is performed according to a uniform pattern. In particular, it is important to determine the natural color point and / or the intensity of the natural light.Thus, the invention provides a colour temperature sensing module and illumination system as claimed in the independent claims. Advantageous embodiments of the invention are the subject of the independent claims.In a first aspect, a color temperature sensor module is provided, comprising: a light sensor having a detection region configured to receive light, wherein the sensor is capable of supplying detection signals to a processing unit, wherein the processing unit is capable of calculating a color temperature value and optionally also an intensity of the light received by the detection region on the basis of the detection signals obtained by the light sensor and outputting corresponding information, a power source configured to power the light sensor and the processing unit, and a transmission unit configured to transmit information representing the calculated color temperature value using a wireless interface.The module comprises a direction indicator unit configured to output a direction indicator signal to the processing unit.The direction indication signal indicates a spatial direction in which the detection range of the light sensor is aligned.The direction indicator unit may consist of a magnetometer and / or a gyroscope. The gyroscope can in particular output a spatial orientation of the module to the processing unit.The processing unit may output direction indication information based on the direction indication signal output to the transmission unit.The energy source can consist of a photo element, an energy buffer, preferably a capacitor or a battery, or a combination of these.The light sensor may comprise at least two light band filters and may determine at least two visible light bands, and preferably comprises at least two photodiodes with integrated color filters.The processing unit may output the color temperature as a color coordinate and / or a calibrated color coordinate.The transmission unit may receive signals using the wireless interface and may forward the received signal to the processing unit.The processing unit may evaluate the received signal and adjust operating parameters of the color temperature sensor module based on the received signal.The color temperature may be a correlated color temperature.The light sensor can comprise at least one of the RGB, RGBC and / or IR sensors and is designed with light attenuation, a gray filter and / or a UV filter.In another aspect, there is provided a lighting system comprising a colour temperature sensor module as described above and an actuator for actuating a lighting device, in particular an LED, a transmission unit configured to receive data transmitted from the colour temperature sensor module using a wireless interface, and a control unit controlling operating parameters of the lighting device, wherein the actuator is configured to control the lighting device based on the data received from the colour temperature sensor module.The control unit can extract color temperature information, intensity information and / or direction information from the received data and can correspondingly change operating parameters of the lighting device. The control unit may evaluate the directional information and may change the operating parameters only when the directional information matches a direction set for the operating device.The operating device may adapt the operating parameters that correspond to the light emitted by the lighting device to the color temperature and / or intensity indicated by the extracted color temperature information and / or intensity information.The actuation device may receive data from more than one color temperature sensor module and the control unit may evaluate the extracted temperature, intensity and / or direction information and adjust the operating parameters of the lighting device based on the direction information, preferably using a stored function.The invention will be described below also with reference to the figures. Fig. 1 shows a schematic arrangement of a color temperature detecting module according to the invention. FIG. 2 shows an illumination system according to the invention.FIG. 1 shows a wireless color temperature sensor module 1. The sensor 2 may be an RGB sensor and may output detection signals related to a color, a color temperature and / or a light intensity captured by the detection region 3 of the sensor 2. The module 1 includes a processing unit 4, such as a microcontroller, for calculating a color / color temperature from the signals provided to the processing unit 4 by the sensor 2. The processing unit 4 calculates and outputs values relating to the intensity, color and / or color temperature of the detected (ambient and / or natural) light that falls on the detection region 3.The processing unit 4 can be connected to a transmission unit 5 with a wireless interface 6, e.g. an RF interface, in order to wirelessly transmit information and in particular the calculated and / or detected information. The transmission unit 5 can of course also alternatively or additionally provide an interface for wired transmission.The wireless interface 6 may be capable of transmitting information via Wi-Fi / WLAN, Bluetooth, ZigBee, or using other wireless protocols or standards. For a wired as well as for a wireless interface 6, information can be transmitted using, for example, an IPV4 or IPV6 protocol. Thus, the transmission unit 6 is used to transmit the information calculated by the processing unit 4 and / or to directly transmit the detection signal received from the sensor.The colour temperature sensor module is also connected to a power source 7 which supplies the sensor 2 and the processing unit 4. The current source 7 of the module 1 is preferably provided on or in the module 1 and thus enables an independent current supply independently of a supply network. This stand-alone power source 7 of the module 1 may employ a photo element 8 such as a photo / solar cell and / or an electrical energy buffer such as a capacitor 9 or a battery,... (the photo element 8 is of course mounted on the module in a position accessible to ambient or natural light). The transmission unit and the interface of the transmission unit can also be supplied by this energy source 7. The capacitor 9 may also be provided in conjunction with the power source 7 to store power supplied from the power source 7.In order to allow control of the lighting fixtures, for example in order to provide inside a natural light mimic outside a building, it may be advantageous to use more than one colour temperature sensor module to determine the colour temperature and / or the intensity of the natural and / or ambient light outside the building or the area in which the detection should take place. The detection can of course also be performed internally, for example if the color temperature sensor module should be used for detecting the color temperature and / or intensity in a specific environment.For such control, it is advantageous to know the direction from which the color temperature information originates. The sensor 2 of the color temperature sensor module 1 normally "looks" in a specific direction, for example it accepts light from a specific direction in which the detection range 3 of the sensor 2 points. The module 1 can therefore comprise a magnetometer 10 and / or a gyroscope (not shown), which can be connected to the processing unit 4 and provide information on which direction the detection area 3 points. Thus, the module 1 can not only transmit information regarding the color temperature (correlated color temperature) and / or the intensity of the light detected by the sensor 2, but can also recognize and transmit information regarding the viewing direction of the sensor 3.Referring to FIG. 2, the transmission unit 5 and the interface 6 of the module 1 may wirelessly transmit the information. This information can be recorded by a central control unit 20 or by an actuating device 21 (e.g. a lighting fixture, ballast and / or driver) in the building, which controls lighting devices within a building or in a defined area directly or indirectly. In particular, the artificial lighting devices may be controlled depending on, and in particular in accordance with, the information obtained from the color temperature sensor module 1.According to one aspect of the invention, the actuating device 21 can be designed during startup of the actuating device 21 such that it evaluates and uses only information from specific modules. For example, it can be designed in such a way that the operation of the lighting devices (e.g. LED) is changed only if the evaluation of the information obtained from the actuating device 21 indicates a specific direction.Therefore, there may be actuators 21 which only respond to information transmitted from modules 1 pointing in a particular direction, for example north, east, west or south or an intermediate direction. In FIG. 2, the detection area 3 of the module 1 could point e.g. to east, and thus the information transmitted by this module 1 contains corresponding data.A gyroscope may also be used to determine a spatial orientation of the module 1. This information can be used, for example, to compensate for the signals output by the sensor 2 or to modify the calculation carried out by the processing unit 4 in order to take account of an non-optimum spatial orientation of the detection region 3.The module 1 can be part of a lighting system 22 and the actuating device 21 can actuate a lighting device 23 or a light source, which can in particular consist of an LED or an LED string. The operation device may also include a transmission unit 24 configured to correspond to the transmission unit 5 included in the color temperature sensor module 1. Therefore, the transmission unit 24 of the actuating device 21 also comprises a wireless interface 25 if the transmission unit 5 is implemented in the module 1 with a wireless interface 6.The actuating device 21 also comprises a control unit 26 which controls the parameters of the lighting device 23. The control unit 26 controls these parameters and the lighting device on the basis of the information obtained from the module 1 via the transmission unit 24.In particular, the control unit 26 may set the operating parameters of the lighting device 23 to adjust the color temperature, the emitted intensity of the light, the brightness, and other characteristics in the emitted light, based on the information obtained from the module 1. The actuating device 21 preferably comprises a plurality of light sources, e.g. of different colour and / or colour temperature, in order to enable a coordination between the colours / colour temperatures. For example, at least one RGB light source and / or at least two light sources emitting white light at different temperatures (for example 6000 K and 5700 K) may be present, and a change in the operating parameters results in a change in the emitted light color and / or color temperature. In addition, the light sources can be dimmed. Thus, the light emitted by the illumination device can be adapted to ambient or natural light in a specific area or a specific spatial direction.The actuator 21 can thus adjust the parameters according to a function stored in a memory unit (not shown) functionally connected to the actuator and / or based on information stored in the actuator. For example, a look-up table may be used to determine operating parameters associated with particular measurements of the color temperature sensor module 1 or its areas. For each color temperature or arrangement of color temperatures recorded or captured by the module 1, the control unit 26 may adjust the operating parameters according to an evaluation of the function or the values stored in the look-up table.It goes without saying that modes of operation of the actuating device can lie in the central control unit 20. In this case, for example, a transmission unit 24', an interface for wireless transmission 25' and / or a control unit 26' can be implemented in the central control unit 20. The central control unit 20 can then receive the information from the module, evaluate the information and send control commands to connected actuation devices 21', which thereupon correspondingly adapt control parameters of their lighting devices 23'.Multiple modules 1, 1', 1" with detection regions 3, which can point in different directions, can also be used in the illumination system 22 for influencing the light emitted by the illumination devices 23, 23' of the system 22. In particular, the actuator 21 and / or the central control unit 20 can take into account the information transmitted by the modules 1, 1', 1" in various proportions depending on the settings established during the start-up phase. A weighting factor may be set to indicate to what extent information from sensors pointing in a particular direction should be considered. By way of example, information from modules 1, 1', 1" pointing in one direction is assigned more weight and thus have a greater influence on the operating parameters to be set, while information which is evaluated as coming from another direction has a lesser influence. For example, colors and color temperatures can be mixed / tuned according to information received from the module 1 which is set to be the main information source, while the tuning / mixing resulting therefrom is changed to some extent based on the information from the module 1' and the module 1". Of course, it can also be the case that information is treated the same or that only one selection is used at all.The actuating device 21 can furthermore comprise a control element by means of which the respective direction from which information should be evaluated can be adjusted. A potentiometer which can be rotated in a 360° range can be used, for example, to define the direction. When information is received from a module 1, 1', 1", it should be used only for setting operating parameters if the specified direction matches the direction of the received information. The direction in which the detection ranges of the module 1, 1', 1" point is indicated by arrows in FIG. 2.Again, Fig. 1 is considered. The light sensor 2 of the module 1, 1', 1" can have two or more light filters (marked as dotted, checkered and dashed regions of the detection region 3) in order to filter light in the visible spectrum. Preferably, three or more of these filters are used. The processing unit 4 converts the sensor data into correlated color point data (for example, RGB, CCT, x, y, XYZ, UV or similar coordinates) and / or intensity data. The transmission unit 5 sends the colour and / or intensity data in a suitable format to the actuation device 21 or to the central control unit 20. The photo unit 8 serves as a power source of the module 1. If it is dark, for example at night, no data is required by the module 1 and thus the module 1 does not have to be electrically operated.The invention also enables independent control of tunable light sources. No wiring is required, since the module 1 is independent and does not require any data or power connections. While the module 1 can be put into operation, it does not need to be put into operation, and it can provide information for an entire building depending on the range of the wireless transmission interface.If the building has matching actuation devices 21 with tunable light sources, these can be connected to a control network. The network can be built in any type of spatial structure, for example 802.15.4 PHY. The selection may be by programming, but a custom infrared network could also be used. Connection to a bus through the use of a bus interface, for example for connection to a DALI or DSI bus, would require an additional, and preferably wireless, gateway to connect the module 1 wirelessly to the respective bus.The actuating device 21 inserted in the building can operate independently in two operating modes: in a first operating mode, in which it adapts to natural light. In this mode, information about the color temperature (intensity) is needed. Second, it can operate in a balance mode in which natural light is balanced, for example, when there is no light or a low light level or an extreme color temperature.Due to the photoelement 8, the module is independent and energy can be introduced by the light absorbed by the photoelement. The module 1 only detects when light is present on the photocell, since in absolute darkness it is not necessary to transmit the information about ambient or natural light. However, the module may comprise a buffer such as a battery or capacitor 9 which may be used when the light incident on the photoelement 8 falls below a predetermined minimum, i.e. the voltage supplied by the photoelement 8 falls below such a minimum value. This can be detected by the processing unit 4.When the processing unit is supplied by the buffer, this phase can be used to transmit a standard signal or a signal indicating that no further information is to be expected from the module, for example when there is normally a period in which information is transmitted from the module and is expected from the actuating device 21 or the central control unit 20. This may be, for example, a signal indicating that the module is transitioning to a sleep mode. The actuator may then send standard information about the color temperature or intensity to correspondingly change the operating parameters. In addition, the energy from the buffer can be used to save operating parameters of the module 1 before all power is drawn.The sensor 2 made of an RGB or RGBC sensor (an RGB clear pixel sensor) may include an integrated analog-to-digital converter (ADC) or a system-on-chip (system-on-chip) ADC (SoC ADC). This sensor can be used to obtain correlated color temperature (CCT) and ambient light intensity. Calibration of the sensor is, however, necessary in most cases. The calibration can be carried out automatically, for example periodically, by the processing unit 4 and corresponding calibration information can be stored in the module 1.The module 1 may also comprise an infrared sensor integrated or separately provided in the sensor 2 to obtain a real 3 or 4 band analysis of the ambient / natural light. Light attenuation (grey filter) and / or a UV filter is preferably likewise used to extend the lifetime of the sensor.The current source 7 supplies the sensor 2 and the ADC / SoC ADC. Both can be operated in an energy saving mode in which only a few mW (milliwatts) are consumed, for example 1-5 mA at 1.8 to 1.3 volts. Voltage stabilization can optionally be effected using a low dropout regulator (LDO) or a zener diode 11. A capacitor may be used as buffer 9 to buffer load spikes occurring at the radio frequency and / or the analog-to-digital converter parts of module 1.A cost-effective SoC unit can be used for processing data and data transmission of module 1, for example a unit for 2.4 GHz IEEE 802.15.4-2006 and ZigBee transmission can be used (e.g. TI CC2538). The SoC may provide a physical layer 802.15.4 for transmission, large memory for the protocol stack, and low power consumption of the processing cores, as well as various input and output devices for AD conversion and runtime monitoring.In the processing unit 4, calibration data of the sensor 2 can be stored, for example, in a memory unit of the processing unit. This information may be updated, for example, when a signal is received from the wireless interface 6. The SoC may also include the RF module equipped with antenna matching (balun that switches between a balanced signal (two signals working against each other, where the ground is irrelevant) and an unbalanced signal (a single signal working against ground or pseudo ground)) and an antenna. Instead of radio frequency transmission, an infrared transmitter and / or receiver may also be included in the color temperature sensor module 1 to enable infrared transmission.It goes without saying that the module can also be contacted wirelessly by the central control unit 20 or a configuration terminal, for example a portable computer terminal, in order to enable configuration of the module. Thus, the processing unit 4 can adapt parameters such as the calibration parameters of the sensor when corresponding information is obtained from the transmission unit 5 and received via the interface 6.The magnetometer or compass, as shown in FIG. 1, supplies the data about the direction of the sensor to the transmission partners and in particular to a building transmission network. The putting into operation of the sensors and / or the combination of a plurality of sensor data is thus very simple, since in particular only the directional information presented with the information by a module has to be evaluated in order to determine whether the information is relevant or to determine to what extent this information should be used by the central control unit 20 or the actuating devices 21.

Claims

A colour temperature sensor module (1) comprising: - a light sensor (2) having a sensing area (3) adapted to receive light, the light sensor (2) being capable of outputting sensing signals to - a processing unit (4), the processing unit (4) being capable of calculating a colour temperature value and optionally also an intensity of the light received from the sensing area (3) on the basis of the sensing signals received from the light sensor (2) and outputting corresponding information, - a power source (7) adapted to electrically supply the light sensor (2) and the processing unit (4), and - a transmission unit (5) adapted to transmit information representing the calculated colour temperature value using a wireless interface (6), the colour temperature sensor module (1) comprising a direction display unit (10), which is designed to output a direction indication signal to the processing unit (4), and wherein the direction indication signal is designed to indicate a spatial direction in which the detection region (3) of the light sensor (2) is directed.The color temperature sensor module (1) according to claim 1, wherein the direction display unit (10) is made of a magnetometer and / or a gyroscope.The colour temperature sensor module (1) according to any one of the preceding claims, wherein the processing unit (4) is configured to output direction indication information to the transmission unit (5) based on the direction indication signal.The colour temperature sensor module (1) according to any of the preceding claims, wherein the energy source (7) represents a photo element (8), an energy buffer (8), preferably a capacitor or a battery, or a combination thereof.Colour temperature sensor module (1) according to any of the preceding claims, wherein the light sensor (2) comprises at least two light band filters and is configured for detecting at least two visible light bands, and preferably comprises at least two photodiodes with integrated colour filters.The colour temperature sensor module (1) according to any of the preceding claims, wherein the processing unit (4) outputs the colour temperature as a colour coordinate and / or a calibrated colour coordinate.Colour temperature sensor module (1) according to any of the preceding claims, wherein the transmission unit (5) is adapted to receive signals using the wireless interface (6) and is capable of forwarding the received signal to the processing unit (4).The colour temperature sensor module (1) according to claim 7, wherein the processing unit (4) is configured to evaluate the received signal and to adjust operating parameters of the colour temperature sensor module (1) based on the received signal.The color temperature sensor module (1) according to any one of the preceding claims, wherein the color temperature is a correlated color temperature.Colour temperature sensor module (1) according to one of the preceding claims, wherein the light sensor (2) comprises at least one of the RGB, RGBC and / or IR sensors and is designed with light attenuation, a grey and / or a UV filter.Lighting system (22) comprising a colour temperature sensor module (1) as claimed in claim 1, and an actuator (21) for actuating a lighting device (23), in particular an LED, comprising - a transmission unit (24), which is implemented using a wireless interface (25) for receiving data transmitted from the colour temperature sensor module (1), and - a control unit (26), which controls operating parameters of the lighting device (23), wherein the actuator (21) is implemented for controlling the lighting device (21) on the basis of the data received from the colour temperature sensor module (1).The lighting system (22) according to claim 11, wherein the control unit (26) is configured to extract color temperature information, intensity information and / or direction information from the received data and is configured to correspondingly change operating parameters of the lighting device (23).The lighting system (22) according to claim 12, wherein the operating device (21) adjusts the operating parameters so as to tune the light emitted from the lighting device (23) to the color temperature and / or intensity indicated by the extracted color temperature information and / or intensity information.Lighting system (22) according to claim 12 or 13, wherein the actuating device receives data from more than one colour temperature sensor module (1, 1', 1"), and wherein the control unit (26) evaluates the extracted colour temperature, intensity and / or direction information and adjusts the operating parameters of the lighting device on the basis of the direction information, preferably using a stored function.

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