Patent Publication Number: US-10779369-B2

Title: Light fixture with LEDs of multiple different wavelengths

Description:
BACKGROUND 
     The present invention relates to light fixtures and particularly to light fixtures having multiple different wavelengths of LEDs. 
     Luminaires or light fixtures are capable of reproducing a wide gamut of colors by combining light from, for example, a plurality of LED light sources. White is a color that is commonly desired to be produced by a luminaire. To produce white, it is common to energize all LEDs in the luminaire so that white light with the highest luminous flux is produced. 
     When creating white light from LEDs, it is often characterized by the Correlated Color Temperature (CCT) from warm white (around 2500K) to cool white (around 5000K). In general, warm white is produced using less blue light and more red light, and cool white is produced using more blue light and less red light. 
     In addition to color temperature, light can be characterized by its ability to accurately render color on a subject. The Color Rendering Index (CRI) provides a representation of an artificial light&#39;s accuracy of producing the full range of colors in a subject in comparison to a standardized source (typically a source representing an incandescent lamp or daylight). A perfect CRI score is 100, which indicates that the artificial light source renders color to the human eye as well as the standardized source. 
     A newer method to evaluate color rendition is TM-30 (R f ), which includes a system for evaluating the fidelity of a light source when compared to a reference tungsten halogen source or to daylight. TM-30 (R f ) is determined using a well-defined process, such as is described in IES TM-30-15 published by the Illuminating Engineering Society (IES). In particular the (R f ) metric defined in TM-30 is a measure of rendering color fidelity. 
     In a setting in which cameras (e.g., still cameras or video cameras) are being used, light selection must take into account the fact that cameras do not see light the same way as the human eye. This is particularly true for digital cameras that utilize CCD or CMOS sensors as the imaging-capturing interface. Due to this difference in the human eye observer and the digital camera, subjects, such as human skin tones, when illuminated by a light with a high CRI or TM-30 (R f ) (which looks good to a human observer) can appear quite poor to a digital camera. 
     In order to predict a light&#39;s ability to accurately render color when captured by a television camera and viewed on a display, the Television Light Consistency Index (TLCI) was created by the European Broadcasting Union (EBU). The TLCI is based on a mathematical calculation implemented in software called TLCI-2012, which is specified in EBU Tech 3355. Like the CRI, the TLCI indexes light up to a maximum score of 100. In general, when recording on a camera in a studio setting, a higher TLCI is considered desirable. 
     SUMMARY 
     Historically, the selection of light sources (e.g., LEDs of different wavelengths) in a luminaire is based on the environment in which it will be used. For example, if a luminaire will be used for a live performance, the selection of light sources will be consistent with the production of light that produces the best color rendering for a live performance, which is generally consistent with a high TM-30 (R f ) score. Similarly, if a luminaire will be used for a televised studio performance, the selection of light sources will be consistent with the production of light that produces the best color rendering for a studio performance, which is generally consistent with a high TLCI score. Conflicts can arise when a particular luminaire is used for a studio performance with a live audience. 
     The present invention provides an LED light fixture comprising a substrate and a plurality of LEDs mounted on the substrate, wherein the plurality of LEDs include a lime/mint light source accounting for at least 25% of the total lumen output, and a deep red light source accounting for at least 0.5% of total lumen output. The lime/mint light source preferably accounts for at least 35% (more preferably at least 50% and even more preferably at least 70%) of the total lumen output. In a preferred embodiment, the lime/mint light source accounts for at least 80% of the total lumen output. 
     The deep red light source preferably accounts for at least 0.75% (more preferably at least 1.0% and even more preferably at least 1.5%) of the total lumen output. In a preferred embodiment, the deep red light source accounts for at least 2.0% of the total lumen output. 
     The LED light fixture can further comprise a cyan light source that accounts for 1% to 50% of the total lumen output. For example, the cyan light source can account for 1% to 30% (preferably 1% to 20%, more preferably 2% to 15%) of the total lumen output. In a preferred embodiment, the cyan light source accounts for 2% to 10% of the total lumen output. 
     The LED light fixture can further comprise a red/red-orange light source that accounts for 1% to 20% of the total lumen output. For example, the red/red-orange light source can account for 2% to 15% (preferably 3% to 12%, more preferably 5% to 10%) of the total lumen output. 
     The LED light fixture can further comprise a blue/indigo light source that accounts for 1% to 10% of the total lumen output. For example, the blue/indigo light source can account for 2% to 5% (preferably 3% to 4%) of the total lumen output. 
     In one embodiment of the invention, the fixture further includes a processor for calculating a color mix and driving the LEDs. Preferably, the processor is programmed to produce a color mix having a CCT in the range of 2700-6500K, a TM-30 (R f ) of at least 90, and a TLCI of at least 95. For example, at a CCT of about 6500K, the TM-30 (R f ) is at least 92 and the TLCI is at least 95, and at a CCT of about 5000K, the TM-30 (R f ) is at least 92, and the TLCI is at least 95. 
     Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an LED luminaire having an LED light source embodying the present invention. 
         FIG. 2  is an exploded view of the LED light source of  FIG. 1 . 
         FIG. 3  is a front view of an LED assembly from the light source of  FIG. 2 . 
         FIG. 4  is a graph comparing the TLCI numbers for the prior art mixes and examples described in the specification using a best spectral metamer. 
         FIG. 5  is a graph comparing the TM-30 (R f ) numbers for the prior art mixes and examples described in the specification using a best spectral metamer. 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. 
     The lighting fixture  20  illustrated  FIG. 1  is a luminaire that can be used for entertainment lighting, such as in a theatre or studio. The lighting fixture  20  includes a light source  22  that produces light, a mixing assembly  24  that mixes the light, a gate assembly  26  through which the light passes after exiting the mixing assembly  24 , and a lens assembly  28  that receives the light from the gate assembly  26  and projects it toward the desired location. 
       FIGS. 2-3  illustrate a sample light source  22  comprising an LED assembly that produces light in multiple wave lengths. The LED assembly includes a substrate in the form of a printed circuit board  30  supporting a plurality of the LEDs  34  arranged in a hexagonal array. In the illustrated embodiment, the hexagonal array includes sixty LEDs  34 , with five LEDs  34  arranged along each side of the six-sided array. The array is sixty-nine millimeters side-to-side and eighty millimeters corner-to-corner. Each LED  34  is spaced from the adjacent LEDs  34  by a distance of about ten millimeters, and there is no LED at the center of the array. It should be understood that the precise type, number, and positioning of the LEDs can be modified substantially without departing from the teachings of the present invention. 
     A primary optic holder  40  is mounted on the printed circuit board  30  and includes a series of through holes  42  that are each adapted to receive the corresponding LED  34 . Each through hole  42  includes a tapered surface  44  that surrounds the corresponding LED  34 . Additional details regarding the light source  22  and the primary optic holder  40  can be found in U.S. Patent Pub. No. US2012/0140463A1, which is hereby incorporated by reference in its entirety. 
     The light source  22  further includes collimating optics in the form of twelve collimator packs  52  ultrasonically welded to the primary optic holder  40 . Each collimator pack  52  includes a back plate  54  and five collimator lenses  56  protruding from the back plate  54  toward the primary optic holder  40 . Each collimator lens  56  is positioned in a corresponding through hole  42  of the primary optic holder  40  and includes a parabolic surface that functions to reflect light from the corresponding LED  34  into the mixing assembly  24  by total internal reflection. The surface of the collimator lens  56  is slightly spaced from the tapered surface  44  of the primary optic holder  40 . Each collimator lens  56  includes a cylindrical recess  60  that receives the corresponding LED  34 . Alternatively, the collimator packs  52  could be formed as a single piece molded glass optic. 
     The present invention provides an LED luminaire that has the ability to produce a color mix that unexpectedly produces a light mix that results in subjects, particularly human skin tones, looking good to both a human observer and on camera. This is particularly useful when a televised or recorded broadcast includes a live audience. 
     As used herein, the following colors of LEDs are deemed to produce the dominant wavelengths listed in Table 1 below. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
             
            
               
                   
                   
               
               
                   
                 Dominant 
                   
               
               
                   
                 Wavelength, nm 
               
            
           
           
               
               
               
               
            
               
                   
                 Color 
                 Minimum 
                 Maximum 
               
               
                   
                   
               
               
                   
                 Deep Red 
                 651 
                 675 
               
               
                   
                 Red 
                 621 
                 650 
               
               
                   
                 Red- 
                 610 
                 620 
               
               
                   
                 Orange 
               
               
                   
                 Green 
                 506 
                 540 
               
               
                   
                 Cyan 
                 491 
                 505 
               
               
                   
                 Blue 
                 451 
                 490 
               
               
                   
                 Indigo 
                 420 
                 450 
               
               
                   
                   
               
            
           
         
       
     
     Table 2 lists examples of bin coordinates for specific phosphor-converted LEDs to produce Amber, Lime, and Mint, although variations in those coordinates are possible. 
     
       
         
           
               
               
               
               
               
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                   
                 x1 
                 y1 
                 x2 
                 y2 
                 x3 
                 y3 
                 x4 
                 y4 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 PC-Amber 
                 0.5622 
                 0.4372 
                 0.5576 
                 0.4326 
                 0.5775 
                 0.4132 
                 0.5843 
                 0.4151 
               
               
                 PC-Lime 
                 0.3819 
                 0.5055 
                 0.4191 
                 0.5790 
                 0.4327 
                 0.5655 
                 0.3972 
                 0.4986 
               
               
                 PC-Lime 
                 0.3770 
                 0.5080 
                 0.3930 
                 0.5010 
                 0.4290 
                 0.5700 
                 0.4150 
                 0.5830 
               
               
                 PC-Mint 
                 0.3972 
                 0.4986 
                 0.3830 
                 0.5077 
                 0.3703 
                 0.4825 
                 0.3846 
                 0.4749 
               
               
                 PC-Mint 
                 0.3846 
                 0.4749 
                 0.3703 
                 0.4825 
                 0.3608 
                 0.4639 
                 0.3752 
                 0.4572 
               
               
                 PC-Mint 
                 0.3752 
                 0.4572 
                 0.3608 
                 0.4639 
                 0.3515 
                 0.4453 
                 0.3659 
                 0.4396 
               
               
                 PC-Mint 
                 0.3651 
                 0.4504 
                 0.3679 
                 0.4561 
                 0.3792 
                 0.4437 
                 0.3819 
                 0.4490 
               
               
                   
               
            
           
         
       
     
     The luminaires of the present invention are designed to receive a signal indicating a desired Correlated Color Temperatures (CCTs) (e.g., from 2700K to 6500K) and are programmed to calculate an output composite light spectrum utilizing the spectral power distribution (SPD) of the available light sources. The SPD of each available light source is stored in a memory in the luminaire. The output composite light spectrum is calculated using metamer control to match a desired target spectrum. For example, the target spectrum could be the brightest spectrum, the best spectral (incandescent) spectrum, or any other chosen spectrum. Color matching by metamer control is a generally known process. 
     For example, U.S. Pat. No. 8,403,523 discloses techniques for maximizing the luminous output of a luminaire while simultaneously minimizing the chromaticity error between an output composite light spectrum and a target light spectrum. U.S. Pat. No. 8,384,294 discloses general techniques for controlling the output of a luminaire to achieve a desired color output for the luminaire. The techniques account for production variations in individual LEDs. U.S. Pat. No. 8,723,450 discloses techniques for controlling the spectral content of the output of a luminaire (i.e., basic metamer control). The techniques allow for individual control of the drive values for particular colors. After increasing or decreasing the amount of a particular color desired in the output spectrum of the luminaire, the drive values of the other colors required to achieve the desired output of the luminaire are recalculated. U.S. Pat. No. 8,593,074 discloses techniques for mimicking the color temperature changes of an ideal black-body radiator based on a target color, a color temperature setting, and an intensity value for the target color. A color temperature transform is then used to determine output drive values for luminaire light sources that achieve the desired output for the luminaire. The four patents referenced earlier in this paragraph provide sufficient disclosure of the use of metamer control to achieve an output composite light spectrum utilizing a known array of light sources, and each of the four patents is hereby incorporated by reference in its entirety for such disclosure. 
     Table 3 lists the LED color mixes and flux ratios for a first prior art LED luminaire using red, mint, blue, and indigo LEDs. The data provided in the chart represent the field lumens when each color of LEDs is operating at maximum output. 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Prior Art Color Mix 1 
               
            
           
           
               
               
               
               
            
               
                   
                   
                 Field 
                   
               
               
                   
                 Color 
                 Lumens 
                 Flux Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Red 
                 834 
                 8.45% 
               
               
                   
                 Mint 
                 8617 
                 87.26% 
               
               
                   
                 Blue 
                 331 
                 3.35% 
               
               
                   
                 Indigo 
                 93 
                 0.94% 
               
               
                   
                   
                 9875 
               
               
                   
                   
               
            
           
         
       
     
     In order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix operating to produce white light at various Correlated Color Temperatures (CCTs) from 2700K to 6500K using a best spectral (incandescent) metamer. After the best spectral output was determined for each CCT, the TLCI and TM30 (R f )) were calculated at discrete CCTs using the known calculation engines. The results of these studies for the Prior Art Color Mix 1 are provided in Table 4 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 4 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Prior Art Color Mix 1 
                 2700 
                 68.4 
                 83 
               
               
                   
                 Prior Art Color Mix 1 
                 3000 
                 90.3 
                 91 
               
               
                   
                 Prior Art Color Mix 1 
                 3200 
                 91.8 
                 93 
               
               
                   
                 Prior Art Color Mix 1 
                 4000 
                 93.1 
                 92 
               
               
                   
                 Prior Art Color Mix 1 
                 4300 
                 91.9 
                 89 
               
               
                   
                 Prior Art Color Mix 1 
                 4500 
                 92.2 
                 90 
               
               
                   
                 Prior Art Color Mix 1 
                 5000 
                 89.7 
                 89 
               
               
                   
                 Prior Art Color Mix 1 
                 5500 
                 87.1 
                 89 
               
               
                   
                 Prior Art Color Mix 1 
                 6000 
                 84.7 
                 88 
               
               
                   
                 Prior Art Color Mix 1 
                 6500 
                 82.0 
                 86 
               
               
                   
                 Prior Art Color Mix 1 
                 7000 
                 79.3 
                 85 
               
               
                   
                   
               
            
           
         
       
     
     The following Table 5 lists the LED color mixes and flux ratios for a second prior art LED luminaire using red, red-orange, mint, blue, and indigo LEDs. The data provided in the chart represent the field lumens when each color of LEDs is operating at maximum output. 
     
       
         
           
               
             
               
                 TABLE 5 
               
             
            
               
                   
               
               
                 Prior Art Color Mix 2 
               
            
           
           
               
               
               
               
            
               
                   
                   
                 Field 
                   
               
               
                   
                 Color 
                 Lumens 
                 Flux Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Red 
                 647 
                 7.10% 
               
               
                   
                 Red-Orange 
                 1155 
                 12.68% 
               
               
                   
                 Mint 
                 7144 
                 78.41% 
               
               
                   
                 Blue 
                 117 
                 1.28% 
               
               
                   
                 Indigo 
                 48 
                 0.53% 
               
               
                   
                   
                 9111 
               
               
                   
                   
               
            
           
         
       
     
     In order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix in a manner similar to that described above. The results of these studies for the Prior Art Color Mix 2 are provided in Table 6 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 6 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Prior Art Color Mix 2 
                 2950 
                 89.0 
                 91 
               
               
                   
                 Prior Art Color Mix 2 
                 3200 
                 91.0 
                 92 
               
               
                   
                 Prior Art Color Mix 2 
                 3500 
                 92.0 
                 92 
               
               
                   
                 Prior Art Color Mix 2 
                 4000 
                 93.0 
                 92 
               
               
                   
                 Prior Art Color Mix 2 
                 4300 
                 93.0 
                 91 
               
               
                   
                 Prior Art Color Mix 2 
                 4500 
                 92.0 
                 91 
               
               
                   
                 Prior Art Color Mix 2 
                 5000 
                 91.0 
                 90 
               
               
                   
                 Prior Art Color Mix 2 
                 5500 
                 89.0 
                 90 
               
               
                   
                 Prior Art Color Mix 2 
                 5600 
                 89.0 
                 90 
               
               
                   
                 Prior Art Color Mix 2 
                 6000 
                 88.0 
                 89 
               
               
                   
                 Prior Art Color Mix 2 
                 6500 
                 86.0 
                 88 
               
               
                   
                 Prior Art Color Mix 2 
                 7000 
                 83.0 
                 87 
               
               
                   
                   
               
            
           
         
       
     
     The following Table 7 lists the LED color mixes and flux ratios for a third prior art LED luminaire using red, PC-Amber, lime, green, cyan, blue, and indigo LEDs. The data provided in the chart represent the field lumens when each color of LEDs is operating at maximum output. 
     
       
         
           
               
             
               
                 TABLE 7 
               
             
            
               
                   
               
               
                 Prior Art Color Mix 3 
               
            
           
           
               
               
               
               
            
               
                   
                   
                 Field 
                   
               
               
                   
                 Color 
                 Lumens 
                 Flux Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Red 
                 682 
                 10.69% 
               
               
                   
                 PC-Amber 
                 1,067 
                 16.72% 
               
               
                   
                 Lime 
                 3,543 
                 55.53% 
               
               
                   
                 Green 
                 517 
                 8.10% 
               
               
                   
                 Cyan 
                 440 
                 6.90% 
               
               
                   
                 Blue 
                 94 
                 1.47% 
               
               
                   
                 Indigo 
                 37 
                 0.58% 
               
               
                   
                   
                 6380 
               
               
                   
                   
               
            
           
         
       
     
     In order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix in a manner similar to that described above. The results of these studies for the Prior Art Color Mix 3 are provided in Table 8 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 8 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Prior Art Color Mix 3 
                 2700 
                 86.8 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 3000 
                 88.8 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 3200 
                 89.9 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 4000 
                 90.2 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 4300 
                 91.3 
                 92 
               
               
                   
                 Prior Art Color Mix 3 
                 4500 
                 91.3 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 5000 
                 92.0 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 5500 
                 89.1 
                 92 
               
               
                   
                 Prior Art Color Mix 3 
                 6000 
                 93.5 
                 94 
               
               
                   
                 Prior Art Color Mix 3 
                 6500 
                 94.0 
                 93 
               
               
                   
                 Prior Art Color Mix 3 
                 7000 
                 94.5 
                 93 
               
               
                   
                   
               
            
           
         
       
     
     The present invention recognizes the enhanced rendering of skin tones achieved by the strategic use of deep red light combined with lime/mint light. The colors lime and mint are being grouped for this purpose because it has been found that either lime or mint can achieve the desired results. In this regard, unless otherwise stated, reference to “lime/mint” shall include any LED having bin coordinates that fall with the range set forth in Table 9. 
     
       
         
           
               
               
               
               
               
               
               
               
               
             
               
                 TABLE 9 
               
               
                   
               
               
                   
                 x1 
                 y1 
                 x2 
                 y2 
                 x3 
                 y3 
                 x4 
                 y4 
               
               
                   
               
             
            
               
                 Lime/Mint 
                 0.3210 
                 0.3874 
                 0.4191 
                 0.5790 
                 0.4400 
                 0.5655 
                 0.3494 
                 0.3842 
               
               
                   
               
            
           
         
       
     
     Similarly, the colors red and red-orange are being grouped because it has been found that either red or red/orange can achieve the desired results. In this regard, reference to “red/red-orange” is intended to cover any light that falls within the dominant wavelength ranges defined for red or red-orange above. Similarly, the colors blue and indigo are being grouped because it has been found that either blue or indigo can achieve the desired results. In this regard, reference to “blue/indigo” is intended to cover any light that falls within the dominant wavelength ranges defined for blue or indigo above. 
     The following tables list the color mixes of three different LED luminaires embodying aspects of the present invention, and separate tables that provide the calculated TLCI and TM-30 (R f ) numbers for multiple CCTs. It is noted that each includes some amount of deep red and also a relatively large amount of lime/mint. The color mix tables 10, 12, and 14 provide the total (full power) lumens for each color and the ratios of each color to the total (full power) lumens of the luminaire. 
     
       
         
           
               
             
               
                 TABLE 10 
               
             
            
               
                   
               
               
                 Example Color Mix 1 
               
            
           
           
               
               
               
               
               
            
               
                   
                 LED Color 
                 Number of LEDs 
                 Lumens 
                 Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Deep Red 
                 8 
                 279.44 
                 1.25% 
               
               
                   
                 Red 
                 12 
                 1259.76 
                 5.65% 
               
               
                   
                 Red-Orange 
               
               
                   
                 PC Amber 
               
               
                   
                 Mint 
                 46 
                 19109.78 
                 85.71% 
               
               
                   
                 Cyan 
                 6 
                 835.08 
                 3.75% 
               
               
                   
                 Blue 
                 8 
                 642 
                 2.88% 
               
               
                   
                 Indigo 
                 4 
                 171.08 
                 0.77% 
               
               
                   
                   
               
            
           
         
       
     
     As was done with the prior art color mixes, in order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix in a manner similar to that described above. The results of these studies for the Example Color Mix 1 are provided in Table 11 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 11 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Example Color Mix 1 
                 2700 
                 59.9 
                 81 
               
               
                   
                 Example Color Mix 1 
                 3000 
                 88.3 
                 89 
               
               
                   
                 Example Color Mix 1 
                 3200 
                 92.6 
                 92 
               
               
                   
                 Example Color Mix 1 
                 4000 
                 96.4 
                 92 
               
               
                   
                 Example Color Mix 1 
                 4300 
                 97.4 
                 93 
               
               
                   
                 Example Color Mix 1 
                 4500 
                 97.6 
                 93 
               
               
                   
                 Example Color Mix 1 
                 5000 
                 98.2 
                 94 
               
               
                   
                 Example Color Mix 1 
                 5500 
                 97.1 
                 94 
               
               
                   
                 Example Color Mix 1 
                 6000 
                 98.1 
                 95 
               
               
                   
                 Example Color Mix 1 
                 6500 
                 98.8 
                 95 
               
               
                   
                 Example Color Mix 1 
                 7000 
                 99.0 
                 95 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 12 
               
             
            
               
                   
               
               
                 Example Color Mix 2 
               
            
           
           
               
               
               
               
               
            
               
                   
                 LED Color 
                 Number of LEDs 
                 Lumens 
                 Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Deep Red 
                 8 
                 279.44 
                 1.36% 
               
               
                   
                 Red 
               
               
                   
                 Red-Orange 
                 12 
                 1673.28 
                 8.16% 
               
               
                   
                 PC Amber 
                 6 
                 1364.52 
                 6.65% 
               
               
                   
                 Mint 
                 36 
                 14955.48 
                 72.93% 
               
               
                   
                 Cyan 
                 12 
                 1670.16 
                 8.14% 
               
               
                   
                 Blue 
               
               
                   
                 Indigo 
                 10 
                 563.5 
                 2.75% 
               
               
                   
                   
               
            
           
         
       
     
     As was done with the prior art color mixes, in order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix in a manner similar to that described above. The results of these studies for the Example Color Mix 2 are provided in Table 13 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 13 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Example Color Mix 2 
                 2700 
                 87.8 
                 90 
               
               
                   
                 Example Color Mix 2 
                 3000 
                 73.5 
                 88 
               
               
                   
                 Example Color Mix 2 
                 3200 
                 92.2 
                 92 
               
               
                   
                 Example Color Mix 2 
                 4000 
                 93.8 
                 94 
               
               
                   
                 Example Color Mix 2 
                 4300 
                 93.9 
                 93 
               
               
                   
                 Example Color Mix 2 
                 4500 
                 94.3 
                 95 
               
               
                   
                 Example Color Mix 2 
                 5000 
                 95.1 
                 95 
               
               
                   
                 Example Color Mix 2 
                 5500 
                 94.5 
                 94 
               
               
                   
                 Example Color Mix 2 
                 6000 
                 94.7 
                 94 
               
               
                   
                 Example Color Mix 2 
                 6500 
                 96.4 
                 94 
               
               
                   
                 Example Color Mix 2 
                 7000 
                 96.5 
                 94 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 14 
               
             
            
               
                   
               
               
                 Example Color Mix 3 
               
            
           
           
               
               
               
               
               
            
               
                   
                   
                 Number of 
                   
                   
               
               
                   
                 LED Color 
                 LEDs 
                 Lumens 
                 Ratio 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Deep Red 
                 10 
                 348.7 
                 2.08% 
               
               
                   
                 Red 
                 16 
                 1679.68 
                 10.02% 
               
               
                   
                 Red-Orange 
               
               
                   
                 PC Amber 
                 8 
                 1819.36 
                 10.85% 
               
               
                   
                 Lime 
                 23 
                 9579.5 
                 57.14% 
               
               
                   
                 Green 
                 7 
                 1368.78 
                 8.16% 
               
               
                   
                 Cyan 
                 10 
                 1391.8 
                 8.30% 
               
               
                   
                 Blue 
                 4 
                 321 
                 1.91% 
               
               
                   
                 Indigo 
                 6 
                 256.62 
                 1.53% 
               
               
                   
                   
               
            
           
         
       
     
     As was done with the prior art color mixes, in order to quantify the color rendering ability of this color mix, virtual experiments were run on the color mix in a manner similar to that described above. The results of these studies for the Example Color Mix 3 are provided in Table 15 below. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 15 
               
               
                   
                   
               
               
                   
                   
                   
                 TM-30 
               
               
                   
                 CCT, K 
                 TLCI 
                 (R f ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Example Color Mix 3 
                 2950 
                 96.0 
                 93 
               
               
                   
                 Example Color Mix 3 
                 3200 
                 97.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 3500 
                 98.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 4000 
                 99.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 4300 
                 99.0 
                 93 
               
               
                   
                 Example Color Mix 3 
                 4500 
                 99.0 
                 93 
               
               
                   
                 Example Color Mix 3 
                 5000 
                 99.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 5500 
                 99.0 
                 95 
               
               
                   
                 Example Color Mix 3 
                 5600 
                 99.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 6000 
                 99.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 6500 
                 99.0 
                 94 
               
               
                   
                 Example Color Mix 3 
                 7000 
                 99.0 
                 94 
               
               
                   
                   
               
            
           
         
       
     
     Table 16 provides data regarding the emitter drive condition (percentage of full) for each group of LEDs of Example Color Mix 3 to emit white light at several different color temperatures using the best spectral metamer calculation. The corresponding Yfrac (relative intensity compared to all emitters at full power), CRI, TLCI, and TM-30 (R f ), are provided for each color temperature. 
     
       
         
           
               
               
               
               
               
               
               
               
               
               
               
               
             
               
                 TABLE 16 
               
               
                   
               
               
                   
                 Deep 
                   
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                   
                 Red 
                 Red 
                 Amber 
                 Lime 
                 Green 
                 Cyan 
                 Blue 
                 Indigo 
                 Yfrac 
                   
                 TM-30 
               
               
                 CCT 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 TLCI 
                 (R f ) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 2700 
                 100 
                 0 
                 40.88 
                 23.87 
                 0 
                 12.56 
                 18.55 
                 6.31 
                 19.97 
                 96 
                 93 
               
               
                 3000 
                 100 
                 0 
                 44.81 
                 29.1 
                 0 
                 18.73 
                 26.32 
                 10.04 
                 23.44 
                 97 
                 94 
               
               
                 3200 
                 100 
                 0 
                 45.93 
                 32.86 
                 0 
                 22.78 
                 32.13 
                 13.01 
                 25.69 
                 97 
                 94 
               
               
                 4000 
                 100 
                 0 
                 49.99 
                 46.45 
                 1.73 
                 40.56 
                 58.33 
                 28.9 
                 34.31 
                 99 
                 94 
               
               
                 5600 
                 86.47 
                 0 
                 47.3 
                 58.29 
                 9.42 
                 64.89 
                 100 
                 61.02 
                 42.24 
                 99 
                 94 
               
               
                 6500 
                 68.6 
                 0 
                 39.14 
                 52.3 
                 11.3 
                 63.7 
                 100 
                 66.15 
                 38.1 
                 99 
                 94 
               
               
                   
               
            
           
         
       
     
     Table 17 provides data regarding the emitter drive condition (percentage of full) for each group of LEDs of Example Color Mix 3 to emit white light at several different color temperatures using the brightest metamer calculation. The corresponding Yfrac (relative intensity compared to all emitters at full power), TLCI, and TM-30 (R f ) are provided for each color temperature. 
     
       
         
           
               
               
               
               
               
               
               
               
               
               
               
               
             
               
                 TABLE 17 
               
               
                   
               
               
                   
                 Deep 
                   
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                   
                 Red 
                 Red 
                 Amber 
                 Lime 
                 Green 
                 Cyan 
                 Blue 
                 Indigo 
                 Yfrac 
                   
                 TM-30 
               
               
                 CCT 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 (%) 
                 TLCI 
                 (R f ) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 2700 
                 100 
                 100 
                 100 
                 100 
                 100 
                 74.27 
                 0.00 
                 57.27 
                 97.01 
                 64 
                 81 
               
               
                 3000 
                 41.79 
                 100 
                 100 
                 100 
                 100 
                 100 
                 100 
                 39.02 
                 98.23 
                 69 
                 80 
               
               
                 3200 
                 0 
                 94.01 
                 100 
                 100 
                 100 
                 100 
                 100 
                 50.80 
                 96.28 
                 73 
                 83 
               
               
                 4000 
                 0 
                 62.09 
                 100 
                 100 
                 100 
                 100 
                 100 
                 95.18 
                 90.75 
                 85 
                 90 
               
               
                 5600 
                 100 
                 38.20 
                 0 
                 69.47 
                 100 
                 100 
                 100 
                 100 
                 60.88 
                 53 
                 78 
               
               
                 6500 
                 100 
                 30.90 
                 0 
                 54.48 
                 100 
                 100 
                 100 
                 100 
                 52.50 
                 44 
                 74 
               
               
                   
               
            
           
         
       
     
     The above-referenced TLCI and TM-30 (R f ) numbers for each of the six color mixes discussed above are illustrated in relation to each other in the graphs of  FIG. 4  and  FIG. 5 , respectively. 
     Using the above Example color mixes, it was observed that skin tone rendering was good under both stage conditions (i.e., viewed by human eye) and studio conditions (i.e., view through a camera), compared to the prior art color mixes. It is believed that the use of deep red combined with lime/mint in the color mixes results in the good skin tone rendering under both stage and studio conditions. 
     Various features and advantages of the invention are set forth in the following claims.