DE102011009292A1 - Method of controlling hue and saturation of illumination system installed in e.g. touch pad, involves assigning three linear independent color valences in predetermined color space for transformation of Cartesian control signal - Google Patents

Abstract

A device is provided for generating a two-dimensional control signal on a limited area in a Cartesian coordinate system. A device is provided for generating colored mixed light from three LED light sources. The three linear independent color valences are assigned in a predetermined color space for the transformation of Cartesian control signal in the domain on the coordinates of hue and saturation within the gamut. The domain of control signal is clearly mapped within the color space.

Description

The invention relates to a method and a device for controlling hue and saturation of illumination systems with mixed light of at least three primary colors in variable composition.

State of the art

The operation of lighting systems with variable colored mixed light is effected in the prior art with control units for preset or custom lighting scenarios. The input device used are push-button panels or remote controls with pushbuttons.

In DE 10 2008 017 072 For example, a method of converting color information to drive a light source will be described. The method is based on that a color information in a first color space is shifted nonlinearly into a second, larger color space on a line passing through a central point. The method is not dedicated and suitable for transforming a two-dimensional, orthogonal control signal into a color information.

In DE 20 2009 001 286 An LED control unit for controlling multicolored LED lamps is described. Central actuator is here a knob with which either a color choice or a brightness selection can be made or an automatic color change. The device is not suitable for making a selection of hue and saturation in a two-dimensional color space.

In DE 10 2009 003 331 a method for controlling a lighting system is described. When activated, the color locus in the color space traverses a predetermined trajectory that oscillates periodically between the white point and the maximum saturation, whereby the color tone is incrementally traversed on the color wheel. The method is not suitable for the fast and targeted setting of a color location.

From Philips there are controls for color lights with changing colors on the market, which are based on the HSV color model. The control panel "ColourChaser Touch" is built around a wheel (scroll wheel) as a central control element. Push-buttons can be used to sequentially adjust the brightness, hue and saturation light properties on the setting wheel and set them one after the other. Similarly, the remote control for the system "Living Colors" is built by Philips. Here are given as control elements a wheel for the hue and two antagonistic buttons for brightness and saturation. This type of color control requires the operation of two independent controls for the choice of color location and saturation and does not allow to obtain fast information on the extent of the color space and the set position within the color space.

A similar operating concept based on the HSV color model shows the luminaire "Jellyfish" of the company Yantouch. Here, the operation is carried out via a touch panel, which is used in a dynamic manner for horizontal scrolling between different colors or color modes and increases or decreases the brightness in vertical steps via vertical movements. For the routine and fast setting of a color location, the process is cumbersome.

task

The invention has for its object to be able to set the control for a combination of hue (hue) and saturation quickly, intuitively and accurately in a lighting system with color variable mixed light. This object is achieved according to the features of the main claim. Further developments emerge from the subclaims.

The invention arose from the specification that the control of hue and saturation in a lighting system which generates mixed light of several primary colors (at least 3) should be based on input devices which are established in particular in computer technology: touchpads and trackballs.

By way of example, the object is as follows: The control signals of the touchpad are generated on a two-dimensional Cartesian spatial unit, which is delimited by a rectangular boundary. This area is also referred to as "Definition Area" or "Control Area" and provided with the abbreviation "CA".

In contrast, the color spectrum of a lighting system that produces mixed light of (n) -round colors in an affine color space is an irregular polygon with (n) corners. In a lighting system with RGB mixed colors, the polygon is commonly called a color triangle. The general polygon in a color space is still called "gamut" because the German translation "color scale" is misleading.

The basic problem is that domain of definition and gamut do not represent similar shapes and can be reversibly clearly mapped by a similarity map.

For a reversibly unique image, therefore, further specifications are required, which are derived from the usefulness and intuitive operation.

• – Die zweidimensionale Stellgröße (x, y) wird in einem kartesischen Koordinatensystem auf einem rechteckigen Gebiet (Definitionsbereich) generiert. Die Grenzen des Gebiets können ohne Verlust der Allgemeinheit symmetrisch zum Ursprung gelegt werden, so dass der Stellgrößenbereich wie folgt definiert ist: CA = {(x, y): –x_max ≤ x ≤ x_max, –y_max ≤ y ≤ y_max}. Die Grenzen des Definitionsbereichs sollen mit der physischen Grenze eines Stellgebers im Ortsraum (sprich, dem Rand eines Tastfeldes) übereinstimmen können. Der Definitionsbereich wird aber allgemein für eine Computersteuerung in einem 2D-Zahlenraum vorgegeben sein, z. B. bei 8-bit Ansteuerung der Bereich der ganzen Zahlen mit ((x, y): –127 ≤ x ≤ 127, –127 ≤ y ≤ 127)).
• – Die zweidimensionale Stellgröße (x, y) wird umkehrbar eindeutig auf den Gamut der Beleuchtungsvorrichtung abgebildet und den photometrischen Größen Bunttonwinkel (Farbton, Hue) und Sättigung zugeordnet. Es werden in dieser Schutzschrift folgende Definitionen für Bunttonwinkel (Farbton, Hue) und Sättigung im Farbmodell CIE L*u*v* angesetzt:
  
  In anderen Farbmodellen sind vergleichsweise Definitionen möglich, und das erfindungsgemäße Verfahren ist nicht auf die Darstellung im CIE L*u*v* Farbmodell beschränkt.
• – Die Einstellung der Gesamthelligkeit L* erfolgt durch ein zusätzliches Steuersignal (z : 0 ≤ z ≤ z_max), welches auf L* abgebildet wird. Die Stellgröße L* kann in dem erfindungsgemäßen Verfahren berücksichtigt werden, geht aber nur in Farbmodelle ein, deren Transformation nicht homogen von L* abhängt.
• – Die Stellgröße, die am Ursprung des Definitionsbereichts (sprich, in der Mitte des Stellbereichs) (x, y) = (0,0) generiert wird, wird auf einen vorwählbaren achromatischen Farbort W = (u * / 0 , v * / 0 ) innerhalb des Gamut abgebildet. Dies kann ein Weißpunkt sein (z. B. CIE D65).
• – Die Stellgrößen, die auf dem Rand des Definitionsbereichs generiert werden, werden auf die maximale Sättigung s_max eines Farbtons h_uv auf der Berandung des Gamuts abgebildet.
• – Die Dichteverteilung der unterscheidbaren Farbreize innerhalb des Gamuts soll bei der Abbildung auf die Stellfläche weitgehend erhalten bleiben, damit die Einstellbarkeit unterscheidbarer Farbreize über die gesamte Stellfläche annähernd konstant ist. Anders gesagt, soll eine vorhandene isotrope und homogene Farbmetrik im Farbraum auf die Aktuator-Bedienung im Raum der Einstellparameter übertragen werden. Hierfür ist ein Farbmodell vorteilhaft, welches möglichst isotrope und gleichverteilte MacAdam Zellen aufweist. Die Zellen werden in der Literatur auch in Form von MacAdam Schwellwerteinheiten (SWE) oder Just Noticeable Differences (JND) mathematisch modelliert. Im vorliegenden Kontext gehen diese Größen qualitativ ein, so dass ihre genaue quantitative Definition nicht von Bedeutung ist. Das CIE L*u*v* Farbmodell ist in dieser Hinsicht unter den affinen Modellen eines mit brauchbarer Farbmetrik für das erfindungsgemäße Verfahren und wird für die Beschreibung des Verfahrens und für die beschriebenen Ausführungswege eingesetzt.

The method according to the invention is based on the following specifications:

• The two-dimensional manipulated variable (x, y) is generated in a Cartesian coordinate system on a rectangular area (definition area). The boundaries of the area can be placed symmetrically to the origin without loss of generality, so that the manipulated variable range is defined as follows: CA = {(x, y): -x _max ≤ x ≤ x _max , -y _max ≤ y ≤ y _max }. The limits of the definition area should be able to coincide with the physical limit of a positioner in the position space (that is, the edge of a touchpad). The domain of definition, however, will generally be given for computer control in a 2D number space, e.g. For example, for 8-bit control, the range of integers is ((x, y): -127 ≤ x ≤ 127, -127 ≤ y ≤ 127)).
• - The two-dimensional control variable (x, y) is reversibly clearly mapped to the gamut of the lighting device and assigned to the photometric parameters hue angle (hue) and saturation. The following definitions for hue angle (hue) and saturation in the color model CIE L * u * v * are used in this protection specification:
  
  In other color models, comparisons are possible and the method of the invention is not limited to the representation in the CIE L * u * v * color model.
• - The adjustment of the total brightness L * is made by an additional control signal (z: 0 ≤ z ≤ z _max ), which is mapped to L *. The manipulated variable L * can be taken into account in the method according to the invention, but only enters into color models whose transformation does not depend homogeneously on L *.
• - The manipulated variable generated at the origin of the domain of definition (that is, in the middle of the setting range) (x, y) = (0,0) is reduced to a preselectable achromatic chromaticity coordinate W = (u * / 0 , v * / 0 ) within the gamut. This can be a white point (eg CIE D65).
• - The manipulated variables that are generated on the edge of the domain are mapped to the maximum saturation s _{max of} a hue h _uv on the boundary of the gamut.
• - The density distribution of distinguishable color stimuli within the gamut should be largely retained in the image on the footprint, so that the adjustability of distinguishable color stimuli over the entire footprint is approximately constant. In other words, an existing isotropic and homogeneous colorimetry in the color space is to be transferred to the actuator operation in the space of the adjustment parameters. For this purpose, a color model is advantageous which has as isotropic and equally distributed MacAdam cells. The cells are also mathematically modeled in the literature as MacAdam Threshold Units (SWE) or Just Noticeable Differences (JND). In the present context, these quantities are qualitative, so that their exact quantitative definition is not important. The CIE L * u * v * color model is in this respect among affine models of useful colorimetry for the method of the invention and is used for the description of the method and the described embodiments.

The invention will be explained with reference to the drawings. Show it:

1 the typical gamut of an LED light source with red, green and blue LEDs, shown in the CIE L * u * v * color model.

2 the typical gamut of an RGCB LED light source with additional cyan LED, shown in the CIE L * u * v * color model.

3 illustrates the transformation between the azimuth angle on the footprint and the hue angle in the color space.

3A) the area between the u * -axis and a vector with hue angle h _uv and the amount of maximum saturation S * / uv (h _uv ) is included in the gamut.

3B) the area enclosed between the x-axis and a position vector with azimuth Θ and length P (Θ) in the footprint. The area fraction of the gamut's total area bounded by the hue angle h _uv corresponds to the proportion of the floor space that is bounded by the position vector with azimuth Θ on the entire floor space.

4 the angle-dependent transformation of the azimuth Θ of the footprint to the hue angle h _uv (Θ) of an RGCB light source in the CIE L * u * v * color model.

5 the angle-dependent transformation of the saturation S * / uv (h _uv (Θ)) for center distance P (Θ) on the footprint of an RGCB light source in the CIE L * u * v * color model.

6 the increase of the adjustment accuracy in the area around the achromatic color locus (W) by a weighting of the radial scaling by means of a gamma coefficient.

7A) and 7B) the comparison of the distribution of named color tones on the azimuth of the footprint with the direct (A) and nonlinear (B) mapping of the azimuth to the hue angle (Hue).

8th the block diagram for an embodiment of the invention for operating a RGB lamp with a keypad and a control based on the DMX protocol.

9 an embodiment of the control device in the form of a wall panel for flush mounting with a touchpad as input device for hue and saturation.

10 an embodiment of the control device installed in the base of a table lamp with a trackball as input device for hue and saturation.

11 a pictorial representation of how the scope of operation of the lighting control can be increased by one and Zweifingergesten on the touch panel.

The transformation property of the method according to the invention will be explained in more detail below with reference to the drawings.

In 1 is the graphical representation of a typical RGB gamut for red, green and blue LED fixtures in the CIE L * u * v * color model. The achromatic point W is the CIE D65 white point. The representation is based on the rectangular area (a, b, c, d), which corresponds to the domain of a manipulated variable (x, y) (ie, is not in the CIE L * u * v * color space). In the case of a touchpad, the footprint is assigned to the surface on which touch (x, y) signals can be generated. The footprint is arranged so that its center coincides with the chosen achromatic point W in the CIE L * u * v * color space and that the x-axis of the control space is collinear with the u * -axis of the CIE L * u * v * color space , Since no color representation is possible in the protection font, it is further applied to what extend approximately sectoral colors, which can be limited by name designations (yellow, green, blue, etc.) when the hue angle of the CIE L * u * v * color space is imaged directly one-to-one on the azimuth of the footprint. The ratio of the distances from the achromatic point W to the edge of the gamut on the one hand and on the other hand to the edge of the footprint is color-dependent (angle-dependent) varying. While in the red and blue range, the ratio is approximately one-to-one, the yellow, green, cyan and the purple line is much closer to the achromatic point, as the boundary of the footprint. Therefore, a one-to-one transfer of the hue angle to the azimuth of the footprint will result in an under-representation of the red and blue regions, whereas the orange to cyan and magenta colors are over-represented.

2 shows the presentation as 1 , taking into account the gamut of a light source with additional cyan color valence. This gamut is used as an example for the further quantitative considerations.

• 1. Transformation des Azimuts der Stellfläche auf den Buntton-Winkel: In 3 ist die Abbildung des Buntton-Winkels auf den Azimut der Stellfläche grafisch dargestellt. Um die Vorgabe zu erreichen, dass die Verteilung der (Buntton-Winkel, Sättigung)-Kombinationen auf der ganzen Stellfläche deren Verteilung im Farbraum getreu wiedergibt, wird die Transformation zwischen Azimut und Buntton-Winkel durch eine Vorschrift für die Erhaltung der Flächenproportion bestimmt. Damit ergibt sich die Funktion für den Buntton-Winkel h_uv(Θ) aus der Gleichung:
  
  Durch diese Transformation wird der Azimut im Bereich von etwa 30° (rot) bis 270° (blau) relativ gedehnt und der Bereich von etwa 50° (orange) bis 150° (cyan) relativ gestaucht und damit eine harmonischere Verteilung der Farbtöne über die Stellfläche erzielt. Die Wirkung ist in 7 grafisch veranschaulicht. Es zeigt 7A) die azimutale Zuordnung des Buntton-Winkels (Hue) auf die Stellfläche vor der Transformation und 7B) die Zuordnung nach der Transformation. Während bei der eins-zu-eins Abbildung der Bereich Orange bis Hellblau nahezu 270° auf dem Farbkreis abdeckt und Dunkelblau und Tiefrot mit ihren jeweils kleinen JND/SWE Zellen nur etwa 40° überstreicht, beträgt nach der Transformation der Bereich Orange bis Hellblau etwa 180° und die Bereiche Dunkelblau und Rot einschließend die Purpurlinie erhalten mehr Gewicht.
• 2. Transformation der radialen Koordinate im Definitionsbereich auf die Sättigung im Gamut: Nach der Transformation des Azimuts auf den Buntton-Winkel muss die radiale Koordinate ρ, gemessen von der Mitte des Definitionsbereichs, auf den Sättigungswert s * / uv abgebildet werden. Der Skalierungsfaktor hierzu ergibt sich aus dem geometrischen Verhältnis der Entfernung (P(Θ)) zwischen Flächenberandung und Ursprung im Definitionsbereich einerseits und Gamut-Rand (S * / uv (h_uv(Θ))) zu achromatischem Punkt andererseits. Damit ergibt sich als einfachste Transformation ist eine lineare Beziehung zwischen der Sättigung und dem Abstand zum Ursprung auf der Stellfläche:
  
  Um bei der Ansteuerung eine Gewichtung der kleinen Sättigungen um den achromatischen Punkt herum zu bewirken, und damit eine präzisere Einstellung der Nuancen von weißem Licht zu ermöglichen, kann es vorteilhaft sein, anstelle der zuvor beschriebenen linearen Sättigungstransformation eine sublineare Sättigungstransformation vorzusehen, die analog zu der bekannten Gamma-Transformation mit einem Exponenten γ ≥ 1 angesetzt werden kann:
  
  In 6 ist die Wirkung auf den Verlauf der Sättigungs-Skalierung für drei Gamma-Exponenten (1.0, 2.0, 3.0) exemplarisch dargestellt. Je größer der Koeffizient gegenüber dem linearen Wert (1.0) ist, umso größer wird der Bereich um den achromatischen Punkt subjektiv empfunden, was zu einer präziseren Einstellung von farbneutralem Licht mit leichter Tönung genutzt werden kann. Wichtig ist, dass die gesamte Stellfläche nach wie vor auf den Gamut abgebildet wird und damit die höchste Sättigung am Rand des Gebiets erhalten bleibt: Die Sättigung eskaliert mit steigendem Gamma-Exponenten vernehmbar im Randbereich.
• 3. Übertragung von Farbton (h_uv), Sättigung (s * / uv ) und Helligkeit (L*) auf die Ansteuerung der Lichtquellen. Diese ist nicht Bestandteil des erfindungsgemäßen Verfahrens und kann nach den etablierten Verfahren im Stand der Technik durchgeführt werden. Beispielsweise durch Anwendung der Transformationsvorschriften auf Grundlage des HSV-Farbmodells.

The transformation rule according to the invention is explained below in steps:

• 1. Transformation of the azimuth of the footprint to the hue angle: In 3 the image of the hue angle is plotted on the azimuth of the footprint. To achieve the specification that the distribution of the (hue-angle, saturation) combinations on the entire footprint faithfully reflects their distribution in the color space, the transformation between azimuth and hue angle is determined by a provision for preserving the area proportion. This yields the function for the hue angle h _uv (Θ) from the equation:
  
  By this transformation, the azimuth is relatively stretched in the range from about 30 ° (red) to 270 ° (blue) and the range of about 50 ° (orange) to 150 ° (cyan) relatively compressed and thus a more harmonious distribution of hues over the Floor space achieved. The effect is in 7 graphically illustrated. It shows 7A ) the azimuthal assignment of the hue angle to the footprint before the transformation and 7B ) the assignment after the transformation. While in the one-to-one illustration the range orange to light blue covers nearly 270 ° on the color wheel and dark blue and deep red with their respective small JND / SWE cells cover only about 40 °, after transformation the range orange to light blue is about 180 ° and the areas dark blue and red including the purple line get more weight.
• 2. Transformation of the radial coordinate in the domain of definition to the saturation in the gamut: After the transformation of the azimuth to the hue angle, the radial coordinate ρ, measured from the middle of the domain of definition, must reach the saturation value s * / uv be imaged. The scaling factor for this results from the geometric relationship of the distance (P (Θ)) between surface boundary and origin in the domain of definition on the one hand and gamut edge (p * / uv (h _uv (Θ))) to achromatic point on the other hand. This results in the simplest transformation being a linear relationship between the saturation and the distance to the origin on the footprint:
  
  In order to effect a weighting of the small saturations around the achromatic point during the actuation, and thus to enable a more precise adjustment of the shades of white light, it may be advantageous to provide a sub-linear saturation transformation instead of the previously described linear saturation transformation, which is analogous to that described above known gamma transformation with an exponent γ ≥ 1 can be applied:
  
  In 6 the effect on the course of the saturation scaling for three gamma exponents (1.0, 2.0, 3.0) is shown as an example. The larger the coefficient over the linear value (1.0), the larger the area around the achromatic point is subjectively felt, which can be used for a more precise adjustment of color neutral light with a light tint. It is important that the entire footprint is still mapped to the gamut and thus the highest saturation is retained at the edge of the area: The saturation escalates audibly in the edge area as the gamma exponent increases.
• 3. Transmission of hue (h _uv ), saturation (s * / uv ) and brightness (L *) on the control of the light sources. This is not part of the process according to the invention and can be carried out according to the established processes in the prior art. For example, by applying the transformation rules based on the HSV color model.

The control described has practical advantages over the controls of the prior art. The fact that the achromatic color point (white point) in the center of the footprint is controlled, the intuitive setting of a color neutral lighting is possible with a handle. Nuances of the color temperature result from near-center control points, whereby the adjustment sensitivity in the mid-range range can be adjusted by the described gamma correction.

Similarly, the setting of maximum saturated colors on the boundary of the footprint is intuitively easy to capture. The assignment of the color shades to the sectoral zones of the footprint can be tapped quickly.

The use of commercially available, technically mature touch panels reduces development and production costs. In addition, the established detection of two-finger gestures or the arrangement of hotspots can be used for the lighting control.

embodiment

The method and an embodiment of the device according to the invention for the control of a lighting device with RGB mixed colors will be described with reference to the block diagram in FIG 8th explained. The two-dimensional control signal for hue and saturation is displayed on the touchpad 101 generated by touch. The signal is initially present as (x, y) signal as it is from the controller 102 is made available. The output of the controller is typically a USB standard transmission path. The (x, y) signal is in the calculator 103 a microcontroller according to the invention Tranformationsvorschriften in a (s * / uv , h _uv ) signal for saturation and hue. In the transformations, the signal for the brightness (L *) from the adjusting device can be used for particular developments of the invention in a color model other than the CIE L * u * v * described 104 which is further required for completing the driving of the RGB light sources. The implementation of the (L *, s * / uv , h _uv ) signal in intensity signals for the light sources 106 (Red), 108 (Green), 110 (Blue) is done according to the HSV procedure in the drivers 105 . 107 and 109 ,

The microcontroller 103 can be spatially and organizationally with the drivers 105 . 107 and 109 a device to be arranged and the control of the lights 106 . 108 and 110 on the way between controller and luminaire using a standardized protocol, such as DMX or DALI.

Another advantageous embodiment is that the controller 102 standardized signals in a defined range, such as 8-bit representation (x = -127, ..., 0, ... 127), (y = -127, ..., 0, ... 127) gives off, as well as the adjusting device 104 for the total brightness (L * = 0, ..., 255). The transformation of the standardized three signal values (L *, x, y) to the values required for color mixing for controlling the individual drivers for the light sources takes place in the controller 103 , which of the lamp as well as the drivers 105 . 107 . 109 and has information about the luminaire-specific gamut. The advantage of this division of tasks is that the adjusting device does not have to be adapted to the specific characteristics of different luminaires and can be offered in a generalized design.

A further advantageous structuring of the system can be achieved by the data required for the transformation on the gamut of the lights 106 . 108 . 110 by means of a suitable bidirectional protocol from a centrally located controller 103 read from the lights and used for the transformation.

For a development of the invention with the operation of the lighting system in parallel over several touch panels 101 It should be noted that the transformations according to the invention are reversibly unambiguous, that is, from one in the microcontroller 103 stored illumination state (L *, s * / uv , h _uv ) the coordinates (x, y) can be redetermined in order to enable a change to a plurality of independent positioning devices and the generation of optical or acoustic feedback based thereon.

In 9 an embodiment of the device according to the invention in the form of a control panel for installation in flush-mounted boxes is shown, wherein a touchpad (touchpad) serves as a central input device. It may be advantageous in terms of manufacturing technology if almost the entire front of the panel is occupied by the touchpad. A simplifying the operation segmentation into individual functional areas is a structured cover 203 achieved. The sections allow the following functions: Adjustment of hue and saturation on the surface 200 , Setting the overall brightness on the track 202 , Storage and retrieval of settings on the emergency spots 201 ,

Another embodiment is based on 10 explains: The input device according to the invention for hue and saturation is here in the socket 300 a table lamp as trackball 301 integrated. The adjustment of the total brightness is done with the slider 302 and the storage and retrieval of settings on the buttons 303 ,

Operation can be made simpler and more convenient when various one and two finger gestures on the touchpad, as known from the application in computer operation, are transferred to the light control. In 11 some interpretations are shown.

gesture 401 illustrates a short finger touch that turns the light on or off without changing the color location.

gesture 402 FIG. 2 illustrates a zoom-in motion by outward spreading of two fingers, in which the described saturation gamma correction is enhanced, ie exponent γ is expanded to 1.0.

gesture 403 Figure 11 illustrates a zoom-out motion by in-merging two fingers, in which the described saturation gamma correction is reduced, ie, the exponent γ is contracted to 1.0.

gesture 404 illustrates a rotary motion with two fingers, in which the hue (Hue) is adjusted according to larger or smaller angles.

It should be noted that the detection of gestures on pressure-sensitive input devices is the subject of several industrial property rights, inter alia WO 96/11435 . US 2006/0026521 and US 2007/0252821 ,

LIST OF REFERENCE NUMBERS

101

Touchpad

102

Touchpad controller

103

Arithmetic unit, transformation (x, y) to (h, s *)

104

Input device signal for total brightness (L *)

105

Driver for light source red

106

Light source red

107

Driver for light source green

108

Light source green

109

Driver for light source Blue

110

Light source blue

200

Touchpad for hue / saturation

201

Button for presets (Store / Recall)

202

Linear actuator for total brightness

203

front cover

300

light socket

301

Control ball for hue / saturation

302

Sliding plate for total brightness

303

Button for presets (Save / Recall)

400

Touchpad for Hue / Saturation

401

Gesture: keying, on / off

402

Gesture: zoom in, increase gamma exponent

403

Gesture: zoom out, zoom out gamma exponent

404

Gesture: Rotate, tune shade

CA

Control Area (definition area of the 2D control signal

h, h _uv

Hue, hue angle, Hue = arctanv / u in CIE L * u * v *

L *

Brightness, Lightness, 3rd coordinate in CIE L * u * v *

RGB, RGCB

Red-Green-Blue, Red-Green-Cyan-Blue mixed light system

s *, s * / uv

saturation

S *, p * / uv,

Limit of saturation on the gamut edge

(u *, v *)

Coordinates in color space CIE L * u * v *

W

Achromatic point, white point, achromatic point

(x, y)

Value pair from the definition range of the actuating signal

± x _max , ± y _max

Lower / Upper limit Definition range Control signal, x / y coordinate

γ

Exponent for radial weighting function (gamma correction)

ρ

Radius in the definition area Control signal = √ x² + y²

P

Limit value of the radius in the definition area control signal

Θ

Azimuth angle in the domain Control signal = arctany / x

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008017072 [0003]
• DE 202009001286 [0004]
• DE 102009003331 [0005]
• WO 96/11435 [0048]
• US 2006/0026521 [0048]
• US 2007/0252821 [0048]

Claims (6)

Method for controlling hue and saturation of an illumination system with the production of colored mixed light of different composition, comprising at least one device for generating a two-dimensional control signal (x, y) which is defined on a limited area in a Cartesian coordinate system such that (- x _max ≦ x ≦ x _max , -y _max ≦ y ≦ y _max ), further referred to as a definition range, given to a device for producing mixed color light from at least three light sources, which are assigned to three linearly independent Farbvalences, and in a predeterminable Color space a region of the producible hues and saturations, furthermore referred to as gamut, spans, a predefinable achromatic point within the gamut, an arithmetic unit for transforming the Cartesian control signal (x, y) in the domain of definition to the coordinates hue and saturation (h, s *) within the gamut, characterized hnet , that the domain of definition of the two-dimensional Cartesian control signal is reproducibly and unambiguously mapped by the arithmetic unit to the gamut within the color space spanned by the illuminants of the illumination system. The method of claim 1, wherein the zero value (x, y) = (0, 0) of the control signal corresponding to the geometric center of the domain is mapped to the predetermined achromatic point within the gamut. Method according to Claim 1, in which the control signal generated on the edge of the domain (x, ± y _max ) or (± x _max , y) is reversibly unambiguously mapped onto the edge of the gamut, hence the maximum saturation of the hues. Method according to Claim 1, in which the Cartesian control signal (x, y) is transformed into a polar coordinate system with a radius coordinate (ρ) and an azimuth angle (Θ), the radius coordinate (ρ) is converted to saturation (s * ), the azimuth angle (Θ) is mapped to the hue angle (h, hue, hue), and the uniquely reversible transformation between azimuth angle in the domain and hue angle in the gamut is performed as specified in the domain of the control signal, the proportion of the sector area of arbitrary azimuth interval (Θ ₁ , Θ ₂ ) on the total area of the definition area is set equal to the ratio of the sector area of the hue angle interval (h ₁ , h ₂ ) resulting from the transformation in the total area of the gamut. A method according to claim 1, characterized in that the control signal within the definition area by a touchpad (touchpad) is generated. A method according to claim 1, characterized in that the control signal is generated within the definition area by a control ball (trackball).

Images