DEVICE, LIGHTING DEVICE, AND STORAGE MEDIUM

FIELD OF THE INVENTION

[0001] The present invention relates to the field of lighting, and more particularly, to adjusting a color temperature of a lighting device.

BACKGROUND

[0002] Ledotron digital dimming protocol has realized standardization in IEC62756. In comparison with the traditional TRIAC (Triode for Alternating Current) analog dimming technology, Ledotron dimmers are very easy to install and use, are more superior in terms of compatibility and performance, and support intelligent dimming of LED lamps.

[0003] FIG. 1 schematically shows the principle of Ledotron solution. The lower part of FIG. 1 shows a waveform of a signal outputted by a Ledotron control unit. As can be seen, many sawteeth, which correspond to transmissions of modulated messages, appear on a descending grade per half wave, which requires a circuit to have a high switching frequency and a quick response, thereby improving the cost and the complexity of the circuit.

[0004] In addition, Ledotron solution can only realize a dimming function, but cannot realize color temperature control.

SUMMARY OF THE INVENTION

[0005] A brief summary of the present disclosure is given below to provide a basic understanding of some aspects of the present disclosure. It should be understood that the summary is not an exhaustive summary of the present disclosure. It does not intend to define a key or important part of the present disclosure, nor does it intend to limit the scope of the present disclosure. The object of the summary is only to briefly present some concepts, which serves as a preamble of the detailed description that follows.

[0006] According to an aspect of the present invention, there is provided a method for adjusting a color temperature of a lighting device, comprising: receiving a color temperature adjustment signal and converting the color temperature adjusting signal into adjustment proportion information corresponding to a color temperature adjustment range of the lighting device; encoding, within a specific time period in a cycle of a rectified input signal, the rectified input signal according to the adjustment proportion information, wherein the specific time period is set in a portion of the cycle in which phases of phase cut dimming are cut off; and adjusting the color temperature of the lighting device based on the encoded input signal.

[0007] According to another aspect of the present invention, there is provided a device for adjusting a color temperature of a lighting device, comprising: a control module configured to convert a received color temperature adjustment signal into adjustment proportion information corresponding to a color temperature adjustment range of the lighting device, and to encode, within a specific time period in a cycle of a rectified input signal, the rectified input signal according to the adjustment proportion information, wherein the specific time period is set in a portion of the cycle in which phases of phase cut dimming are cut off; and a driving module coupled to the control module, and configured to adjust the color temperature of the lighting device based on the encoded input signal.

[0008] According to yet another aspect of the present invention, there is provided a lighting device, comprising: a phase cut dimming device, and the device for adjusting a color temperature of a lighting device according to the present invention.

[0009] According to other aspects of the present invention, there are further provided corresponding computer program codes, computer-readable storage medium and computer program product.

[0010] The present invention realizes a color temperature adjustment solution with easy design and low cost, which is combined with the phase cut dimming to thereby lower costs and improve user experience.

[0011] These and other advantages of the present invention will become more apparent through detailed description of preferred embodiments of the present invention in combination with the drawings below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] To further describe the above and other advantages and features of the present disclosure, detailed embodiments of the present disclosure are further described in detail in combination with the drawings below. The drawings, together with the detailed description below, are incorporated in the specification and form a part of the specification. Elements with same functions and structures are denoted with same reference numerals. It should be understood that, these figures only describe typical examples of the present disclosure, but should not be regarded as limiting the scope of the present disclosure. In the drawings:

[0013] FIG. 1 schematically shows the principle of Ledotron solution;

[0014] FIG. 2 is a flowchart of a method 200 for adjusting a color temperature of a lighting device according to an embodiment of the present invention;

[0015] FIG. 3 schematically shows a functional block diagram for implementing the method 200 in FIG. 2;

[0016] FIG. 4 shows an encoding circuit in a control module in FIG. 3;

[0017] FIG. 5 shows a decoding circuit in a driving module in FIG. 3;

[0018] FIG. 6 shows a waveform of a signal outputted by the control module in FIG. 3; and

[0019] FIG. 7 is a block diagram of a device 700 for adjusting a color temperature of a lighting device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, exemplary embodiments of the present disclosure will be described combined with the drawings. For the sake of clarity and conciseness, the description does not describe all features of actual embodiments. However, it should be understood that in developing any such actual embodiment, many decisions specific to the embodiments must be made, so as to achieve specific objects of a developer; for example, those limitation conditions related to the system and services are met, and these limitation conditions possibly would vary as embodiments are different. In addition, it should be appreciated that although developing tasks are possibly complicated and time-consuming, such developing tasks are only routine tasks for those skilled in the art benefiting from the contents of the disclosure.

[0021] It should also be noted herein that, to avoid the disclosure from being obscured due to unnecessary details, only those apparatus structures and/or processing steps closely related to the solution according to the disclosure are shown in the appended drawings, while omitting other details not closely related to the disclosure.

[0022] The color temperature adjusting method 200 according to the present invention will be described in detail in combination with FIG. 2 through FIG. 6 below.

[0023] In practical applications, color temperature adjustment and brightness adjustment on a lighting device are generally performed simultaneously. Advantageously, the method 200 according to the embodiment is combined with the phase cut dimming, and such a combination is in particular cost saving. The method 200 according to the present embodiment will be described hereinafter in combination with phase cut dimming.

[0024] In step 201, a color temperature adjustment signal is received and the color temperature adjusting signal is converted into adjustment proportion information corresponding to a color temperature adjustment range of the lighting device. Specifically, in the present embodiment, a color temperature adjustment signal is received by a control module 30 in FIG. 3, and it is converted into adjustment proportion information corresponding to a color temperature adjustment range of an LED load 303. As shown in FIG. 3, a color temperature range of the LED load 103 is, for example, between 2700k and 5000k, and the color temperature range may be converted into an adjustment proportion of 0-100%. It should be understood that, the color temperature adjustment signal may be transmitted in a wired manner such as a button arranged on a wall, or be transmitted in a wireless manner such as Bluetooth.

[0025] It should be understood that, any suitable existing circuit may be used to realize the reception and the conversion of the color temperature adjustment signal.

[0026] Next, in step 202, within a specific time period in a cycle of a rectified input signal, the rectified input signal is encoded according to the adjustment proportion information, wherein the specific time period is set in a portion of the cycle in which phases of phase cut dimming are cut off. Specifically, in the present embodiment, a rectified input signal refers to rectifying a signal (a waveform of the rectified signal is as shown in FIG. 6) from commercial power (e.g., power supply 300 as shown in FIG. 3), and then inputting the rectified signal into an encoding circuit as shown in FIG. 4, which is hereinafter uniformly referred to as input signal IIN. The encoding circuit as shown in FIG. 4 is included in the control module 301 in FIG. 3, for encoding the input signal IIN. When a control signal Ic from for example a micro control unit (not shown in the figures) in the control module 301 is at a high level, a transistor Q3 is turned on to be grounded, while transistors Q1 and Q2 are turned off. When the control signal Ic is at a low level, the transistor Q3 is turned off, while the transistors Q1 and Q2 are turned on. Referring to FIG. 6, by controlling the transistors Q1 and Q2 to be turned on within a time period [t2, t3] in a latter half cycle of input signal IIN, the input signal IIN is encoded based on the adjustment proportion information of color temperature. In addition, as stated previously, in case of combination with a phase cut dimming scheme, the control signal Ic also controls the transistors Q1 and Q2 to be turned on within a time period [0, tl] in a former half cycle of the input signal IIN, whereby an outputted signal IOUT can simultaneously adjust the brightness and the color temperature of the lighting device.

[0027] According to a variant, the time period [t2, t3] and the time period [0, tl] may also be set in a way opposite to that shown in FIG. 6, that is, the time period [t2, t3] is set in the former half cycle and the time period [0, tl] is set in the latter half cycle. Those skilled in the art can readily envisage a corresponding structure to realize such setting.

[0028] Resistors R16, R17 and R18 in FIG. 4 realize a function of over-current protection. This portion of the circuit will not be repeatedly described herein because it is not related to the contribution of the present invention.

[0029] It should be understood that, the encoding circuit as shown in FIG. 4 is used only as an example, and those skilled in the art can readily envisage other circuit structures to realize the same function.

[0030] It should also be understood that, the transistors mentioned herein include, but are not limited to, a Field-Effect Transistor (FET), an Insulated Gate Bipolar Transistor (IGBT), a Metal -Oxide- Semi conductor Field-Effect Transistor (MOSFET) or a Junction Gate Field- Effect Transistor (JFET), etc.

[0031] Typically, in case that the commercial power frequency is 50Hz, the cycle of the input signal IIN is 10 milliseconds, and the start timing t2 of the color temperature adjustment time period [t2, t3] is advantageously set to be greater than or equal to 8 millisecond. In case that the commercial power frequency is 60Hz, the cycle of the input signal IIN is 8.33 milliseconds, and the start timing t2 of the color temperature adjustment time period [t2, t3] is advantageously set to be greater than or equal to 6.7 millisecond. Such settings may advantageously reduce lamplight flicker, thereby improving user experience.

[0032] Preferably, a duration of the color temperature adjustment time period [t2, t3] is within a range of 50 to 200 microseconds.

[0033] Preferably, a data format for the encoding comprises start bits, data bits and checksum bits. The checksum bits may, for example, be set as an inverse of the data bits.

[0034] For example, assuming that data 5, whose binary representation is ObOOOlOl, is to be transmitted, then the data bits plus the checksum bits are ObOOOlOl 1010.

[0035] Preferably, when data is transmitted, the start bits may, for example, be set as two ones, and transmissions of the two ones are spaced 1 cycle apart, while the data bits and the checksum bits may, for example, be set such that transmissions of each bit is spaced 2 cycles apart.

[0036] It should be understood that, those skilled in the art can also envisage other suitable data formats and transmission schemes.

[0037] Finally, in step 203, the color temperature of the lighting device is adjusted based on the encoded input signal. Specifically, in the present embodiment, a driving module 302 in FIG. 3 includes, for example, a decoding circuit as shown in FIG. 5. As shown in FIG. 5, the encoded outputted signal IOUT is inputted from a terminal VBUS via a rectifier bridge (not shown in the figures). Capacitors C26 and C29 and a resistor R31 form a differential circuit. A transistor Q10 is turned on at a high level, and the encoded signal IOUT reaches an optical coupler U3 via the transistor Q10. A terminal V AC is set to a high level, and becomes a low level in a case where pulses appear in the encoded signal IOUT. A micro processing unit (not shown in the figures) included in the driving module 302 performs decoding by detecting a signal from the terminal V AC. The driving module 302 adjusts the color temperature of the lighting device according to the decoded signal.

[0038] It should be noted that, the circuit portion composed of diodes ZD 10 and ZD2, resistors R49, R50 and R51 and a transistor Q12 in FIG. 5 is used for over-voltage protection function, and the circuit portion composed of a capacitor C7, diodes ZD9 and D20, a transistor Qll and resistors R4, R25, R26 and R48 is used for avoiding light flicker. The two circuit portions will not be repeatedly described herein because they are not related to the contribution of the present invention.

[0039] It should be noted that, the decoding circuit as shown in FIG. 5 is used only as an example, and those skilled in the art can readily envisage other circuit structures to realize the same function.

[0040] The methods discussed above may be completely realized by a computer-executable program, and may also be partially or completely realized by hardware and/or firmware. When they are realized by hardware and/or firmware, or when a computer-executable program is uploaded to a hardware apparatus that can run a program, devices for adjusting a color temperature of a lighting device which are to be described hereinafter are realized. Hereinafter, an overview of these devices will be given without repeating some details having been discussed above; however, it should be noted that, although these devices can implement the methods described previously, the methods are not necessarily implemented by those components of the devices as described or not necessarily implemented by those components.

[0041] FIG. 7 shows a device 700 for adjusting a color temperature of a lighting device according to an embodiment, comprising a control module 701 and a driving module 702, wherein the control module 701 is used for converting a received color temperature adjustment signal into adjustment proportion information corresponding to a color temperature adjustment range of the lighting device, and for encoding, within a specific time period in a cycle of a rectified input signal, the rectified input signal according to the adjustment proportion information, wherein the specific time period is set in a portion of the cycle in which phases of cut phase dimming are cut off; and the driving module 702 coupled to the control module 701, and is used for adjusting the color temperature of the lighting device based on the encoded input signal.

[0042] The device 700 for adjusting a color temperature of a lighting device as shown in FIG. 7 corresponds to the method 200 as shown in FIG. 2. Therefore, relevant details of respective modules in the device 700 for adjusting a color temperature of a lighting device will not be repeatedly described herein because they have been given in detail in the description of the method 200 for adjusting a color temperature of a lighting device in FIG. 2.

[0043] The respective constituent modules and units in the above device may be configured by software, firmware, hardware or a combination thereof. Specific means or manners that can be used for configuration will not be repeatedly described herein because they are well- known to those skilled in the art.

[0044] The present invention further proposes corresponding computer program codes, and a computer program product having stored thereon machine-readable instruction codes. The instructions codes, when read and executed by a machine, can implement the above- mentioned methods according to the embodiments of the present invention.

[0045] Accordingly, a storage medium for carrying the above computer program product having stored thereon machine-readable instruction codes is also included in the disclosure of the present invention. The storage medium includes, but is not limited to, a floppy disc, an optical disc, a magnetic optical disc, a memory card, a memory stick and the like..

[0046] Finally, it should also be noted that, terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusions, such that a process, a method, an article or an apparatus comprising a series of elements not only includes those elements, but also includes other elements not explicitly listed, or but also include elements inherent to such a process, method, article or apparatus. Further, without more limitations, an element defined by the sentence "comprising one... " does not preclude additional same elements which further exist in a process, method, article or apparatus including the element.

[0047] In addition, in the embodiments described herein or shown in the figures, any direct electrical connection or coupling — i.e., any connection or coupling with no additional intermediate element — may also be realized through indirect connection or coupling — i.e., connection or coupling with one or more additional intermediate elements, and vice versa, as long as the general purpose of connection or coupling, for example, sending a certain signal or sending certain information, is substantively maintained. Features from different embodiments may be combined to form other embodiments. For example, variations or modifications described with respect to one of the embodiments may also apply to other embodiments, unless otherwise indicated.

[0048] Although embodiments of the present invention have been disclosed above in detail in combination with the drawings, it should be appreciated that, the embodiments described above are only configured for illustrating the present invention, but do not constitute limitations to the present invention. For those skilled in the art, various modifications and alterations may be carried out for the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention is defined only by the appended claims and equivalent meanings thereof.