TW200904251A - Lighting device with a plurality of light emitters - Google Patents

Abstract

The invention relates to a lighting device (100, 200, 300) with N light emitters (11) (e.g. LEDs) of different primary colors (e.g. R, A, G, B, C) that shall be controlled in such a way that a number k of target values (e.g. color point and/or brightness) are optimally matched, wherein k is typically smaller than N. The control problem is solved by applying at least two different control schemes simultaneously to different light emitters or during different operating conditions to all light emitters. In a first particular embodiment (100), some of the light emitters (G1) may be controlled by a feed forward controller (Cff) while the rest (G2) is controlled by a feedback controller (Cfb). In another embodiment (200), the driving commands of some of the light emitters (G1, G2) may be coupled, thus lumping these light emitters to a virtual light emitter for the purpose of control. In still another embodiment (300), different optimization criteria (C1, C2) are pursued under different operating conditions(Op1, Op2), for example the optimization of color rendering index on the black-body line and the optimization of lumen output elsewhere.

Description

200904251 IX. Description of the Invention: Technical Field of the Invention The present invention relates to a light-emitting device having a plurality of light emitters (particularly LEDs) and for individually controlling the light emitters according to a given target value. member. [Prior Art] A light-emitting device comprising red, green and blue light-emitting diodes (LEDs) is known from US Pat. No. 6,507,159 B2, in which the LEDs are controlled in a feedback loop. The given target tristimulus value is optimally matched. However, the utility of this illuminating device with respect to color gamut and color rendering is limited only by the available three primary colors. SUMMARY OF THE INVENTION Based on this situation, it is an object of the present invention to provide a light-emitting device having improved characteristics, particularly having a large color gamut and good color rendering properties. This object is achieved by a lighting device as claimed in claim 1. Preferred embodiments are disclosed in the accompanying claims. The illumination device according to the invention comprises the following components: a) A number N22 of light emitters having different primary colors, i.e. having different emission spectra under comparable operating conditions (temperature, drive current, etc.). Each light emitter can be a single lamp or a combination of several identical or different lamps. This ^' should understand that the light wheel of the entire illuminating device is superimposed on the light output of all of its N light emitters. And b) a controller for selectively driving the light source to generate a given target value (e.g., a coordinate of a desired color point) of the number k^1 is 130639.d〇i 200904251 by The common light output of the light emitters is optimally matched, wherein at least two different control schemes are applied. In this respect, a "best match" means that the light output (1) of the illuminating device exactly matches the target value, or (Η) reaches the equivalent value as close as possible (eg, reaches one of a predetermined color space) The fixed color point 'one of the color-distance predetermined measures is as close as possible to the light emitter used). ^ Control Scheme" shall mean any unique algorithm or mathematical equation 'by its use for - the light emitter's drive commands can be based on actual input signals (such as target values and measurement signals) and given parameters (such as light emitters) Characteristic) to calculate. If the structure of the associated equation is not @, the two control schemes will be considered different (so the only difference in the parameters (4) would make the equation different. The 'should be more elegant' equation will not contain a case sensitive branch because This will allow a formal combination of completely different control methods to become n programs). Examples of control schemes will be described in more detail with respect to different embodiments of the invention. The number k of the target value and the number ν of the light emitters can be divided into three cases: if k>N', there is usually not enough independent control variables (ie, primary colors) to match all target values; Good approximation. If (4), there is usually a drive command for a unique set of light emitters by which the target value can be reproduced. Finally, if k < N, the available number of primary colors provides an excess of free production: therefore the target value can usually be reworked, but the control problem becomes unimportant. The illuminating device with its application of at least two different control parties is particularly suitable for managing the latter case. It should be noted that the number k of target values defined above generally refers to a target value that can be measured using a sensor measurement or can be measured using an immediate self-sensor measurement such as an observer algorithm. If - for example, the color point and brightness of the lamp are used - the color sensor is measured, it will not be possible to optimally match, for example, a good color rendering target' because this cannot be obtained immediately from the measured color coordinates and brightness. Bu 3 will be applied to this situation. For a lamp having a primary color of N>3, the color rendering properties can be optimized in a similar manner by considering the results of off-line calculations when designing two control schemes' as reviewed in more detail below.

In the first-basic variation of the present invention, the illuminating device is characterized by having two groups of light emitters n, and each group of the wipes is associated with another light emitter of the group. Program. #句说—The driving commands of the clustered light emitters are calculated by one program, and the driving commands of the other group of light emitters are calculated by different equations. If there is more than the primary color N of the target value k, the light emitters can be specifically divided into groups so that the excess degrees of freedom can be handled. 1 In a specific implementation of the above-mentioned first-basic change, the control of the illuminating device includes a controller and a feedback controller, wherein a group of optical transmitters is used by the pre-authorized controller - (pure) pre-control control scheme control and another group of light emitters are controlled by the feedback controller using a feedback & scheme. By applying the pre-control to some of the light emitters, the feedback control object to the residual light emitter can be significantly simplified. Note = The control of the internal control H may also include a pre-receiving component, for example to provide a basic control signal for the backup of a feedback loop. The pre-authorization component can be applied to the same pre-existing method as needed, such as for another group of light-emitting transmitters. 130639.doc 200904251 Preferably, in the feedback control group mentioned above, there are as many light emitters as the target value, i.e., the number k. Therefore, the control object of the target value can be achieved only by the available primary colors, and allows the definition of the feedback loop design. Preferably, the illumination device having the feedback controller includes a sensor coupled to the feedback controller and to determine the brightness and/or color point of the common light output of the light emitter. The sensor thus measures important characteristic values of the common light output, which are typically also specified (directly or indirectly) as target values. The proposed controller can be designed in many different ways. Preferably, it is designed such that it optimizes the color rendering properties (especially the color rendering index (CRI)) and/or the power efficiency of the illumination device. These target values can be optimized offline using a model or experiment such as a lamp. However, since the optimization problem is quite complex (multidimensional, nonlinear, etc.), it is virtually impossible to solve it exactly in real time. The theoretical optimization system for target values such as CRI and efficiency is therefore preferred for use in pre-available controllers to reduce control problems to the number and type of control parameters and target values that can be easily handled. These remaining control parameters and target values (such as brightness and/or color point) are processed in the feedback controller. Preferably, the feedback controller is coupled to the pre-master controller, and the target signal and/or the feedback signal provided to the feedback controller is generated from a component that has been processed by the controller. the way. In particular, the target signal supplied to the feedback controller should be the difference between the base target value and the portion of the base target value that has been achieved by the prior control. Similarly, the feedback signal reporting the actual condition of the control system to the feedback controller should be the total measured signal minus the components of the signals caused by the pre-authorized control loop. Back to the control 130639.doc -10- 200904251 The controller can therefore focus on this part of the control task that remains to be resolved after the completion of (iv). In a first implementation of the first basic variation of the invention having different control groups of light emitters, there is at least one group of light emitters for which the mobile command is at least temporarily constrained by a static relationship (and thus the drive command is used for another group of light emitters by means - different static relationships are not combined or H combined). The static system allows the group-only light-emitting command to calculate the driving commands of all the light emitters of the group. Therefore, the static relationship; the degree of freedom of the light emitter is considered by the east node, because (four) The control problem is simplified. Although the above static relationship between the drive commands is in principle arbitrary, the drive commands of all the light emitters of the group preferably have a fixed pair of opposites: in particular, all drive commands may have The value of the phase or the ratio of the combination = after combining with the subsequent higher level control results in the best color rendering properties and/or power efficiency of the illumination device. In the further development of the above-described embodiments, All light emitters in the considered group (ie, whose drive commands are lightly coupled by a static relationship) are treated as a virtual light in a higher level control scheme by a more: level controller. The quasi-control scheme can then simply be structurally considered to be a real light emitter and a virtual light emitter (which consists of several real light emitters) in the same way. The higher level control scheme can be designed in particular so that it The brightness and/or color point of the illumination device is optimized.

The above higher level controller can be A thousand? Benefits can be provided based on at least some of the target values (such as brightness and color point) - all of the light emitters - pre-control. In addition, the former 130639.doc 200904251 control can be based on the parameters of the development of the well, such as in the degree of control problems are clearly defined (ie, if, Λ and aspects. 傩. Right - there is too much freedom "It is often "(4) system (such as by matrix multiplication). This condition can be achieved by a static relationship "east knot" with several degrees of freedom. The above higher level pre-control scheme can be borrowed The feedback control by an action on the device is supplemented by the special seven-shot benefit step. The feedback control can be operated independently of the off-level control scheme, and the different light emitters can be controlled, or the higher bits can be controlled. Quasi-control schemes for cooperative operation' and, for example, fine tuning, predecessor:: text: 'will describe a different control scheme to achieve a luminaire, a change in soil', which should be noted, all the descriptions of the invention can be combined DETAILED DESCRIPTION OF THE INVENTION According to this variation, there is a first zone of the (at least) operating conditions of the lighting device and a second zone of operating conditions, wherein the application = control scheme. The individual light emitters are therefore at a given time Point system The same treatment, but if other operating conditions are reached, the process can be structurally changed. "Operating conditions" can be used to include the target value, the driving of the light emitter, the actual light-emitting device, and the other Environmental conditions such as temperature and/or any other parameter that affects the operation of the illumination device. As a general example, any kind of control scheme can be applied to the first and second zones of the operating conditions respectively. For example, the pre-administration relative to the feedback control, or the individual-to-integral control with respect to several optical launches (refer to the above) discuss). In a preferred embodiment, the 'solution to the first and second regions of the operating conditions, respectively, differs in the optimization criteria for the common light output of the light emitters being performed. This allows for further step-by-step improvement of the control of the illuminator, as it can be optimized for conditional compliance. In a particular embodiment, the optimization of color rendering " provides priority in the first zone of operation. The color rendering properties can be quantified, for example, by the color rendering index and describe the ability of the light source to reproduce the colors of various objects. However, the term "priority" indicates that the optimization of the color rendering property may not be a better criterion, but the maximum weighting is received in the weighted combination of the optimization criteria. Similarly, the optimization of the lumen output can be given In the second zone of the operating conditions, the priority of the control scheme is continuously changed in the middle zone of one of the operating conditions of the first and second intervals of the operating conditions, so that the continuation between different control schemes can be achieved. The first zone of the flat condition may specifically include the common (target or actual) light body of the light emitter. The 'body line' indicates the color point of the black body at one of the different temperatures, and is especially for the generation of white light. Important. The second zone of operating conditions may thus comprise all color points having a common (target or actual) light output of the light emitters that are more than a predetermined distance from the black body line. Different control schemes in different zones with operating conditions In the illuminating device, at least some of the light emitters can be controlled by a feedback controller using a feedback control scheme. This feedback control allows matching of the targets. The value, regardless of the degree change, the aging of the light emitter, and the like. The controller of the illumination device optionally includes a memory, wherein the library stores a lookup table containing control parameters, especially for a pre-control. The use of tables allows for immediate implementation of complex control schemes, such as the color rendering index of 130639.doc 200904251, where the intermediate value can be determined by a simple interpolation. Although the light emitter can in principle be any kind of lamp (or A group of lamps), preferably including LEDs, phosphor-converted LEDs, organic LEDs (〇LEDs), lasers, phosphor-converted lasers, color fluorescent lamps, color-filtered (color) halogen lamps, and color filters ( High-intensity discharge (HID) lamp and/or color filter (color) ultra-high performance (UHP) lamp. The target value may specifically include the color point, brightness, color rendering index and/or power efficiency of the illuminating device, wherein The following reference numerals in the drawings refer to the same or similar components. The LED lighting device based on additive color mixing has high efficiency, high color rendering index (CRI), adjustable color temperature and allowable To control the color of light. In order to obtain a large color gamut, it is known that the illuminating device is equipped with three primary colors (typical red, green and blue: RGB). With these colors, it can produce warm and cool white light (such as in black body trajectory). From 2500 Kelvin to 6500 Kelvin.) However, the disadvantage of these LED sources with three colors is that they do not result in sufficient color rendering (ie CRI > 80). This can be achieved by using amber LEDs. Replacing the red LED partially solves 'but this only increases Ra and decreases (r9 shows the ability of the lamp to display red objects' reference by the definition of CRI of international C()mmissiQn Qn IllUminati〇n (CIE)), so there is no Total color rendering improvement. Fortunately, this can be achieved by adding an extra color (such as an amber LED) so that the lamp is equipped with four led colors (red, amber, green, and blue · RGB A) 'or a white LED' Match the lamp with four LED colors (red, green, blue and white: rgBW); or by using even 130639.doc •14-200904251 additional colors such as an amber and a cyan LED There are five LED colors (red 'amber, green, cyan and blue: RGBAC). In addition, using more than three primary colors increases the color gamut of the lamp. However, the complexity associated with additional colors increases the number of degrees of freedom (one degree of freedom for each LED color). It is known that three colors have three degrees of freedom, all of which are limited by selected color points (such as χ, 丫 coordinates) and brightness 'and the first four degrees of freedom (introduced by adding, for example, an amber led) are still Opening is not restricted. In addition, it should be observed that the optical properties of the LED vary with manufacturing variations, aging, temperature, and forward current. Therefore, the target color point and brightness are almost impossible to obtain without a suitable feedback system. A system for controlling the color point and brightness of an LED lamp having three primary colors is described in U.S. Patent No. 6,441,558, the disclosure of which is incorporated herein by reference. The system needs to briefly turn off the LEd for light measurement. Therefore, the LED driver must have a fast response time. In addition, a PWM driving method is required to overcome the lEd variation with a forward current. With PWM control, the implementation becomes complicated and (in addition) the full capacity of the unused LEDs. In the following, the various control methods according to the invention are described, which are based on the application of at least two different control schemes and are particularly suitable for the control of illumination devices having more than three primary colors. 1. Example: Pre-combination and feedback control In the first example of a hybrid N>3 primary color LED lamp, the feedback control system is applied to the 3 color and the pre-administration control system is applied to the residual N_3 color. For feedback control, the triple value of the LED light is measured and the control signal for the 3 color is determined from the measured triple value and the target triple value in the feedback controller I30639.doc 200904251. For the pre-administration control, the control signal for the N_3 color is set, for example, to achieve good color rendering and high efficiency of the illuminating device as well as possible. This concept will be explained in more detail below with reference to Figures 1 to 5. Fig. 1 illustrates a case where light having color points Ρι, p2, P4, and five LEDs should be mixed to obtain light having a color point 在一 in a CIE chromaticity diagram. The color points that have been drawn are such that Ρ] corresponds to red, J>2 corresponds to amber color, Ρ3 corresponds to green, ρ4 corresponds to cyan, and ρ5 corresponds to blue. There are several possibilities to subdivide these five primary colors into one group of _3=2 colors (Ν=5) (which is controlled before application), and a group of 3 colors to which feedback control is applied. The feedback control will be considered for red 'breaking # and blue, and the pre-administration control will apply to green and green. As a preparation, first, a case of a light-emitting device having three primary colors deleted will be considered with reference to Figs. The light to be emitted by the LED lamp can be specified by its chromaticity coordinates X and y and its luminous flux. From this equivalent, the triplex values X, Y, and Z can be calculated according to equation (4) of ® 2 . The triple-magnification group is grouped into a vector TV ("double-excited value. The triple-excited value of light that must be perceived by the observer (ie, the person watching the light or the object illuminated by it). And the difference between the three-excited TVs determined in the feedback path of the color control system. / Ideally, the color sensor used in the illumination device should directly sense the triple value. However, 'this will not be achieved. In fact, the value R of the sense of crying by color sensing is grouped into a vector SR („Sensor reading" 卜丄依-similar method for the control of the driver of red, green and blue coffee^ The packets are also grouped into a vector cs ("control signal "). These may be duty cycles for -pulse width modulation control, or current amplitudes for an amplitude modulation control 130639.doc -16 - 200904251. The vectors TV, SR, and CS that are pulled by r, θ are listed in equation (2·2). Figure 3 shows the general setting of the LED color control system for a light with a three-primary color. ο ο j , , with a color sensor, which indicates that the signals discussed above appear in i Μ The brothers are in the system. As for the triple value, except for the output signals TV0 and TVsW, the input signal Tvset and the error signal TVerr are indicated. The transfer function described in the block diagram represents the following parts of the system: ac - controller aD - Driver Sjled - light-emitting diode fioso - optical system, G = oss - optical system, as - color sensor fi = CAL - calibration matrix D as indicated by the dashed line, as indicated by the dashed line 'can be part of the control system The grouping becomes a modular rent, and the transfer function can be easily used for determining it in a calibration procedure. The first module corresponds to a transfer function fiG2T' reference equation from the control signal cs to the triple value τν0 perceived by the human eye ( 2·3) The second module corresponds to a transfer function ^2S reference from the control mark CS to the sensor reading SR;

(2.4). A calibration matrix aCAL can be obtained from the feedback path. The three excited TVs must equal the demand of the triple-excited TV〇 perceived by the observer..., refer to equation (2.5). The block diagram of Figure 3 indicates that the third value determined in the feedback path of the system is linked to the sensor reading by the calibration matrix, which results in the program 1302.6.doc 17-200904251 (2.6). If more than three primary colors of light are mixed, then the grouping becomes the triple value of τν and the three sensor readings that are grouped into SR. However, there are now more control signals. For the example considered with the 5 primary colors, there are 5 control signals, one of the original color red, amber white, green, blue and blue. These groups are grouped into a 罝CS with 5 elements (refer to equation (4.1) of Fig. 4). In addition, a vector csff for the control signal of the original & under control and a vector csfb for the control signal of the primary color under feedback control are defined. In general, CSff has an N·3 element, for example, considering that it has 2 elements. Csfb has 3 elements, referring to equation (4 j).

Qc2t and £c2s are now a matrix of three columns and n=5 rows, that is, one row of each primary color. The transfer function from the control signal to the triple value and the senser reading and acu are determined in a calibration procedure. The system uses solid measurement, which is 5 for the example considered. For each measurement, the control signal for a led color is set equal to one' and the control signal for other LED colors is set equal to zero. The triple value of the light taken with the sensor reading and observed is determined using a spectrometer. The results obtained for the first calibration of the red LED R are shown in equation (4.2). Similar results were obtained in the advance-step calibration measurements for the other four colors, which can then be used to construct the matrix 2 according to equations (4.3) and (4.5) and the associated pre-receiving component of the matrices ( ^ and 2 (: 28, refer to equations (4.4) and (4.6). The relationship between the calibration matrix used in Figures 2 and 3 to determine the light used to control a three-color lamp must be based on equation (47). To (4ιι) adapted to the current situation in which more than three primary colors are mixed. 130639.doc 18 200904251 Figure 5 shows a simplified block diagram of a resulting led color control system for mixing lamps of more than three primary colors, using a color sensor The transfer function ατπ describes how to determine the control signal for the primary color under the pre-administration control from the three values of the target color and brightness. Any suitable method can be used for the previously granted part. The node X of the system has the following effect (I) The theoretical two-intensity vector is theoretically achieved by the pre-conducting component £C2T, ff.csff^ is subtracted from the target vector TVset, and (II) is obtained from the measurement of the second excitation vector to the previously given component GcAL_fic2S, and the frCSff is used for the feedback path. The third excitation vector TVs are subtracted. If the pre-instruction component is not continuously measured, the same sensor can be used to measure both the complete optical output SR and the pre-information component. The feedback controller for the control system of more than three primary colors can be The method is the same as that for the control system of one of the two primary colors, for example, the method known from the U.S. Patent No. 6,507,159, the entire disclosure of which is incorporated herein by reference. RGB) A method of coloring an LED lamp, wherein a color sensor is used to measure the dither value of the mixed light. The color sensor comprises three different parts in the visible spectrum (usually also RGB). Photosensor with spike sensitivity. In summary, the example discloses a method for controlling the target color point and brightness of light mixed with an LED lamp of n>3 primary colors. First, optimizing high luminous efficiency and The brightness value of the balance between good color rendering is determined for all primary colors. Then the 'pre-control system is applied to the N_3 color and the feedback control system is applied to the 3 colors. For the pre-administration control, the setting is for N-3. The control signal of the color is so good that the predetermined color rendering, efficiency and triple value are achieved. For the feedback control of 130639.doc 19 200904251, the triple value of the light of the LED lamp is measured, and the control signal for the 3 color is used. The three values of the measured three values and the target color are determined in a controller. 2. Example: The lumped control for a plurality of light emitters is based on a control device for controlling a light-emitting device having more than three primary colors. The second method is to reduce the number of degrees of freedom. A typical eight-cafe system will have, for example, three degrees instead of the usual four degrees of freedom. This reduction can be achieved by temporarily combining two (or more) degrees of freedom. A simple algorithm to decide: drive the power ratio of the LED. In the simplest case, the combined colors are driven at the same ratio. This method has two important advantages: - a microcontroller can determine the required power ratio for each target color point line; - when the algorithm is used for the available lumens of each color at the current operating temperature, it is also The best value is obtained in the lumen output of the illuminating device. The following description of this example will focus on a combination of red and amber, which is an advantageous combination with respect to the ochre. However, the proposed method is also suitable for groups a of other colors, such as blue and cyan, blue and green, but also for phosphor conversion LEDs having a substantial, intentional blue leakage. Several methods are known in the current best state to convert a color point and a lumen level (X, y, L or u', v, L) into a led color power ratio or work cycle % (Reference) P. Deurenberg et al., "RGB multi-chip modules using various color correction methods" in RGB multi-chip modules. '1, proc.spiE 5914, 2005; 130639 .doc •20-200904251 WO 2002/47438; WO 2002/52901). The main difference between these methods is the storage of optical data (eg X, γ, Z triple excitations; X, y, l color coordinates and lumens) Output). However, generally the program can be explained as follows (for the three-exciting paradigm).

The target color point and light level having the two excitation values ' Υ τ and Ζ τ can be expressed as equation (6′′ in FIG. 6 ), wherein the matrix c describes the CIE set point of the LED as one for the LED color i (where i= The function Di of the duty cycle of R, G, B). The C-matrix contains the CIE 1931 triple value for each lED color, ^, & The reversal of the C matrix (also known as "calibration matrix,,) can be used to determine the desired duty cycle for a target color point. This can be applied directly to any three color (led) system. However, when more than three colors are applied, the matrix c is no longer reversible due to its dimensions (3x4 in the example considered). Combining two LED color channels (only during calculations) can solve this problem. The resulting duty cycles for these two channels can be selected, for example, to be equal. In this case, 'red and amber are preferably combined into a single-work cycle' because these LED colors are closest in the color space. The resulting equation (6·2) of Figure 6 shows that the c-matrix contains a (lumped) CIE 1931 triple exciter (3), υ), for each LED color, where the exponent RA corresponds to - contains the lumped red and The amber color "virtual light emitter". The loop for the given target color point can be found by the subsequent color control period in which the target color point is multiplied by the inverse of the matrix. The method results in a selected color at the temperature effective for the above C system: a maximum lumen output of the unit at the point. Updating the matrix for other temperatures' results in the maximum lumen output at all temperatures. 130639.doc 21 200904251 by Multiple calibrations at different temperatures' or (if some parameters of the output spectrum of the coffee are available) are done by the series of leaves to compensate for temperature drift by the series of f @ J straw. Or, 'can also store each LED The color x, y, w. Equation (6)) The y picker is used to describe the optical output of the LED for all the work at the % and the reference temperature u. The t-index RA indicates the red, amber station or set. The coordinates of the total red and the original color of the amber, and the L system The maximum lumen output of the device at U. The lumen fraction of each of the (primary) primary colors can be obtained by using an inverse matrix shirt according to equation (6.4), where the index τ is used to refer to the non-target color coordinates and lumen output. It is found that the duty cycle for each of these primary colors 2 'each lumen score must be according to Equation 0 5) divided by the individual maximum lumen output and calibration temperature of eight. If any calculated work cycle D is greater than 1 in 1 , the required lumen output helmet method is achieved. By normalizing the duty cycle with respect to the maximum duty cycle, at least the desired color point can be achieved, although the bran ^ ', , , and the overhead output will be reduced. In any duty cycle D In the case of a negative r month, the required color coordinates cannot be achieved in the original color used. If the red and amber LEDs are in the same way, they will get the same duty cycle and thus optimized for maximum The duty cycle of the flux output. The xra and yRA coordinates can be calculated from the triple value as indicated in equation (6.6). Another significant advantage of the method is that the maximum lumen output can be: one color point is uniquely transferred Release Loop, for any number of LED colors. Obviously, more than two LED color sets can also be used together. Figure 7 shows schematically - for four coffees with primary color ragb: : Light unit 1〇 The complete controller configuration. The temperature τ of the heat sink of the device is measured and communicated to the controller 20 by the temperature sensor 13. The former controller 130639.doc -22- 200904251 controller 20 according to the method Determining four control signals (Fig. 6) by combining two colors (R and A) to a virtual light emitter (RA), and by using an associated calibration matrix C (for the measured temperature τ) The inverse of T) is multiplied by the target color point (Χτ ' Υτ ' Ζτ). In addition, the color point (R, 〇, B) of the illuminating unit 1 is measured and transmitted to a feedback controller 3, such as a PID controller, by a color sensing benefit 12. The feedback controller 3 〇 then determines the correction factor for the pre-delivery control signal (DR DA ' DG, DB) ff. The LED 丨丨 is finally driven by the resulting correction control signal.

Figure 8 shows the variation of the system of Figure 7, in which the illumination unit contains a pass-in sense 12' and its LED" is driven by pulse width modulation (pWM) to cause a constant forward current, but Changing the duty cycle or working time 'it basically means that it only turns on periodically and reaches a certain amount of time. This driving method is female, and has the advantage that the forward current does not change the emission wavelength (because the current is always constant at the time of the current). This means that the mixed colors of the unit have less dependence. The horse determines the output (power) of each led color by the early-sensor 1 2, and the Τ ργ»& hand must be turned on in time order to distinguish the color of each separated LED (to go to ^^ ^ ^ Frequency separation). This means that the sensor 12 measures the instantaneous output. through

P Some tests 1 and some simple calculations, the output of each LED color can be determined from the measured (single LED) cD by one color. Bran τ , ‘, , ,, measuring instantaneous output and using PWM to drive LED means that when the working cycle is changed to ρτη^ ^ 支寺, the signal is not changed. Since the PID set point is expressed in the desired cycle of the LEDs at the applied (constant) forward current during the cycle. 5 s s and 疋 do not depend on the selected color 130639.doc -23- 200904251 In order to improve the accuracy of the system, the temperature τ of the heat sink is measured by the temperature sensor 13 and transmitted to the PID controller 30. Based on the measured temperature τ, the PID controller 30 can then change (by prior method) its set point to match the peak wavelength shift of the LED due to its temperature change. Furthermore, the system function is described in Figure 7. ί

In general, the method of lumping two (or more) LEDs is primarily used to determine the initial drive command available to obtain the desired color. However, these initial commands are valid only at a certain temperature T (determining the temperature of the calibration matrix c). Therefore, if the LEDs are also operated at different temperatures (or when they are significantly aged), such pre-command commands alone will not produce the desired color with sufficient accuracy, and feedback control (4) is required to achieve the desired accuracy. The feedback algorithm can have many different forms and can be used, for example, using the color sensor shown - a simple, unfiltered sensor (see us 6 441 558 B1). In all cases, the replay can be constructed such that it operates independently of the selected color point (and therefore the initial drive command). In this case, the 'return algorithm' corrects the initial drive command, so it is used to obtain the desired color point. 3. Example: Changing the optimization criteria is very good - the third-party property that is used to control a light-emitting device with more than three primary colors is optimized for the color point on the black body line (bottle), and the black body line is opened. …optimization. In addition, offline red-cutting and microprocessors have been proposed. Interpolation can be used to provide a dynamic ratio. For the maximum lumen wheel 'out:: Calculated on the drive between the color points in the lookup table. The driving ratio of 4 can be obtained by a simple algorithm line 130639.doc •24- 200904251 As already mentioned, it is difficult to obtain sufficient color rendering for general illumination by using only three LED colors. Thus, at least one other color (e.g., amber color) can be added, however it means that the drive ratio of the LED color can no longer be uniquely calculated by specifying only the desired color point and lumen output. Additional degrees of freedom in a (e.g., RGBA) illumination device can be used to optimize optical technology properties such as CRI, lumen output, or power efficiency (lumen of each used power watt). The graph in Figure 9 shows the significant difference between the lumen output (left) and the color rendering index (right) in this respect, which is optimized for maximum flux rotation (black line) or maximum color rendering (grey line). Drive ratio. The result changes as the temperature of the heat sink rises (the top plot corresponds to room temperature 25t and the bottom plot corresponds to an ascending temperature of about 5〇 °c). In order to improve the above, it has been proposed to optimize the duty cycle for a four (or more) color led system depending on the selected target color point. If the user requires a white color (on the black body line BBL) (where color rendering is important), the power at which the lamp drives its LED color should be optimized for the color rendering properties (CRI, R9, etc.) of the lamp output. In areas where the BBL is clearly removed (where color rendering is not critical), the power applied to each LED color or the total lumen output of the lamp can be optimized. For color points that are very close to the BBL (e.g., with ΔuV < 〇.〇〇5), the drive ratio can be determined by interpolating between the two algorithms. Unfortunately, for a common microprocessor, it is not possible to perform color rendering calculations on-line because such calculations are too complex. One solution to this dilemma is to optimize the drive ratio of the color points on the BBL offline. A pc system can easily perform such complex calculations for a few points. The result can be stored in the microprocessor's memory in the form of a look-up table (LUT) 130639.doc •25- 200904251.拄牮i +』 I- μ τ can interpolate the drive ratio for the target color point between the stored color points. This LUT shovel and _ υ 1 fe system is not shown in Figure 1 0

Figure 11 presents an exemplary flow chart of how to determine the contents of this-LUT. In step 1, the desired range of phase-color temperature (CCT) on the chaos is specified and step 2 regulates the allowable visible difference between discrete steps. Step 3 specifies the amount of memory available to store the LUT. In the step, the discrete CCT value is | in step 2 with an input of $, and in step 5, the discrete CCT value is removed from the list to fit the table into the available memory. Between the remaining points, it must be done - interpolation. Finally, the power level is generated in step 6 for each LED color of the remaining CCT values and at (4) the standard (e.g., maximum CRI). It should be noted that the offline most "algorithm's parameters can be specifically tuned for the application or the light in question. For example, when the t-lumen output is significantly reduced, the color rendering properties are greatly improved from the end to the end of the game. It is too reasonable. A better solution can therefore be found by optimizing the weighted combination of negative and negative output in the color rendering of the previous month and the B-day. k with j 5 into the additional optimization parameters (eg, lumens / watts). Depending on the available LEDs, the number of color centers may require even more restrictions. ^ &lt; Make sure that the output color of the lamp is kept constant, and that the system is typically 罄+η &amp; you are aware of the color of each LED at the current temperature and/or aging. It is possible that the lumens and rumors use this information to directly determine the driving ratio for each color (eg, an algorithm with a German 圔&lt;*, 方程Figure 6) will get the single 130639.doc • 26 - 200904251 The maximum lumen output reaches the drive ratio at which it is. The best driving ratio for the various color points that apparently leave the BBL is found. The target color point of the rhyme leaving but the #近职 can also be found by interpolating between the closest BBL point and the lumen optimization calculation. - Applied calculus The method finds the drive ratio for a color at the reference temperature and also the maximum lumen output. This algorithm can be used to determine the available lumen output for each (lumped) LED color at the current junction temperature. Drive Ratio for Maximum Lumen Output. The techniques described above can be specifically applied to LED fixtures that use more than three LED colors. They are especially suitable for general illumination or LCD back illumination but can also be used for lumen output and Other areas of application where color rendering is important. Figure 12 summarizes the three control examples described above primarily in Figures a) through c). The figure shows illuminators 1 〇〇, 200 and 3 〇〇, which have one The number of target values (such as color point and / or brightness) is the best match to control the different primary colors R, A, G, B, C N = 5 light emitter u (such as LED), which makes the typical Is less than N. The control problem is borrowed This is solved by applying at least two different control schemes simultaneously to different light emitters or to all light emitters during different operating conditions. In the illumination device 100 of Figure a), one of the light emitters & Controlled by a controller Cff, and the group of residual light emitters is controlled by a control, which is connected from a color sensor 12 to 0 in the illumination device 200 of Figure b), by a controller C〇 is sent to the group 130639.doc -27- 200904251 G!, the drive command of the G2 light emitter is coupled, so these light emitters are aggregated to a virtual light emitter for control purposes. Group h Only light emitters are individually controlled. As described with reference to Figure 7, the controller is preferably coupled to a feedback controller for adjusting the control signal based on temperature drift &amp; aging. In the illuminating device 3 of Fig. C), the different optimization criteria are performed by the controlling parties (4) and ^ under different operating conditions 〇pm〇p2, respectively. This can, for example, include optimizing the color rendering index on the black body line and optimizing the lumen output elsewhere. Finally, it is pointed out that 'in the case of the towel, the term, the inclusion, the excluding other elements&lt;, or the step '" or "do not exclude a plurality of, and - the single-processor ^ unit can complete several components The function. The present invention resides in each and every <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Two can be understood with reference to the specific embodiments described above. This specific embodiment is exemplified by the accompanying drawings, in which: Figure "Brothers have a chromaticity diagram with five primary colors, 2 shows the relevant one-head 4=pre-station device; program; general feedback of the best state of the target Figure 3 of the control loop shows a current best power diagram; ^^^, the general feedback control loop of the block diagram 4 shows the basics according to the inclusion of a pre-grant-back feedback control 130639.doc -28-

200904251 A first control w々忐 equation; FIG. 5 shows a block diagram of the first control; FIG. 5 is not related to the second control according to the invention including a plurality of light emitters together The method of the method; Figures 7 and 8 show two changes in the pre-administration control of the second control method according to the ', · and the feedback control; Figure 9 shows that according to different optimization criteria (Left/Right) and graphs of 'comparative-luminous device flux and CRI at different temperatures (up/down) control; Figure 1 shows the same for the invention according to the inclusion criteria optimization criteria An example of a lookup table for a duty cycle of color points on a black body line of the first control method; FIG. 11 is a flow chart for generating a lookup table for a CRI optimization; FIG. 12 (including FIGS. 12a, 12b, and 12c) The three described control methods according to the present invention are summarized in the main diagram. [Main component symbol description] 10 Light-emitting unit 11 Light emitter/LED 12 Color sensor/flux sensor 13 Temperature sensor 20 Higher level controller/pre-controller 30 Feedback controller 31 Color signal Picker 100 illuminating device 200 illuminating device 130639.doc -29- 200904251 300 illuminating device CO higher level controller Cl controller C2 controller Cfb feedback controller Cff pre-administration controller 130639.doc -30-

Claims (1)

200904251 X. Patent application scope: 1. A lighting device (1〇〇, 2〇〇, 300) comprising: a) a number N of light emitters (11) having different primary colors; b) - controller ( 20, 30, cff, Cfb, CO, Cl, C2) for selectively driving the light emitters such that k target values are optimally matched by the common light output of the light emitters Wherein at least two different control schemes are applied by the controller. 2. The illumination device of claim 1 (1, 2, 3, (), "characterized by the number of target values" is less than the number N of light emitters (11). The illuminating device 请求, 2〇〇) of claim 1 is characterized in that at least two groups (Gi, G2, g3) of light emitters (11) are provided, which are controlled according to different control schemes. The light emitting device of claim 3 (1) is characterized by a group (G) of light emitters controlled by a pre-administration control &amp; (cff) with a pre-control scheme, and the other The light transmitter of the group (G2) is controlled by a feedback control scheme. "The control device is controlled by a feedback control scheme. 5. The illumination device (1) of claim 4 is characterized in that the group (Gj's feedback control light emitter is provided with k light emitters. 6. The light-emitting device (1) of claim 4, characterized in that it comprises a sensor (12), the sensor (12) coupled to the feedback controller (Cfb) for determining the brightness and/or color point of the common light output of the light emitters. 130639.doc 200904251 7·as claimed in claim 4 Optical device (1), characterized in that the pre-controller (Cff) is designed to optimize brightness, color point, color rendering properties and/or power efficiency. 8. Illumination device according to claim 4 (1) 〇〇), characterized in that the destination number and/or the feedback signal supplied to the feedback control ii (cfb) is generated from a component associated with the pre-authorization controller (Cff). The illuminating device (2〇〇) of item 3, characterized in that at least one group (GW) of light emitters (11) is used for driving the singularity of the 仫 丄 ^ p 7 system, and thus - static The relationship is at least temporarily transposed. 1 〇· illuminating device (200) of claim 9, wherein the driving commands of all the light emitters of the group (G1, g2) have a fixed ratio relative to each other 11. The illuminating device (2〇〇) of claim 9, wherein f is characterized in that all of the ejector of the group (G1, G2) are processed into one by a higher level controller (20, c〇) Virtual light emitter 12. The illumination device (2〇〇) of claim I, characterized in that the higher level controller (2〇, c〇) is In order to optimize the brightness and/or color point 13. The illumination device (2〇〇) of claim 11 is characterized in that the higher level controller (2〇, c〇) provides all of the light emitters (1) The pre-administration control is based on at least some of the target values and is based on the operating parameters of the illuminating device as needed, in particular the base 130639.doc 200904251 at its temperature (τ). 14 as claimed in claim 13 Illuminating device (200), characterized in that the higher level controller (20, C0) is further supplemented by a feedback controller (3〇) operating on at least some of the optical transmitting benefits (11) . 15. The illumination device (300) of claim 1, characterized in that the first and second regions of the operating conditions (Op 1, Ο ρ2) of the illuminating device are applied, wherein different control schemes (C1, C2) are applied. 16. A lighting device (300) according to claim 15 characterized in that the different optimization criteria of the common light output of the light emitters (1) are respectively carried out in the first and second zones of operating conditions. 17. The illuminating device (3A) of claim 16, /, wherein the optimization of the broad-color nature is given priority in the first zone of operating conditions. 18. The illumination device (3A) of claim 16, wherein the optimization of the lumen output is prioritized in the first region of the operating condition. 19. The illuminating device (3A) of claim 15, wherein the financial control is continuously changed in the first of the operating conditions and in the intermediate portion of one of the first intervals. 20. The illumination device (3A) of claim 15, wherein the first region of the operating condition comprises a black body line of the common light output of the light emitters I30639.doc 200904251. 21. The illuminating device (3A) of claim 15, characterized in that the ith region of the operating condition comprises all color points of the common light output of the light emitters, which are beyond the black lining - pre- ^ Distance. 22. The illumination device (300) of claim 15, wherein at least some of the light emitters of the light emitters are controlled by a feedback controller in a feedback control scheme. 23. The illumination device (100, 200, 300) of claim 1, wherein the remote controller comprises a memory, wherein a lookup table includes control parameters. 24. The illuminating device (1〇〇, 2〇〇, 3〇〇) of claim 1, characterized in that the light emitter comprises a LED, a phosphor converted LED, an organic LED (OLED), a laser, a phosphorescent Volume conversion laser, color fluorescent lamp, color filter (color) halogen lamp, color filter (color) high intensity discharge (HID) lamp and / or color filter (color) UHP lamp. 25. The illumination device (100, 200, 300) of claim 1, wherein the target values comprise the color point, the brightness, a color rendering property, and/or the power efficiency of the light emitters. 130639.doc