1	A VIRTUAL APPROACH TO RAPID LIGHTING FIXTURE DEVELOPMENT FROM DESIGNER’S CONCEPT TO IES PHOTOMETRICS IN DAYS. FUNCTIONAL PROTOTYPES ON DESIGNERS DESK IN DAYS… REDUCED LEAD TIME TO CLOSE ORDERS. REMOVES UNCERTAINTY FROM PROJECTS Solid modeling, digital optical modeling and analysis, rapid prototyping – 3d printing – and the wide availability of fast computing has changed the face of lighting fixture design.
2	A VIRTUAL APPROACH TO RAPID LIGHTING FIXTURE DEVELOPMENT
3	TYPICAL PROJECT The development strategy is applicable to all source types. We have applied it in architectural, film and video, entertainment and scientific / industrial fixtures. One typical project is illustrated – just one of hundreds successfully completed by us. US DOE contacts lighting fixture manufacturers with request for fixture submittals for a new energy initiative. Initiative is to encourage the Peoples Republic of China to adopt energy efficient building design. Federally purchased fixtures to be donated to a Beijing US designed office building, incorporating the best of US “Green” technology.
4	1^ST MEETING DEVELOP SPECIFICATION WITH CLIENT / DESIGNER
5	2ND MEETING – DIGITAL EXCHANGE OF IDEAS Pro/Engineer SOLID MODELING SOFTWARE IS USED TO CREATE MULTIPLE SIMPLE DESIGNS SUBMITTAL OF SIMPLE RENDERINGS TO DETERMINE STYLE AND CONSTRUCTION PREFERENCE
6	STYLE SELECTED – OPTICAL DESIGN STARTS With the style selected, it is apparent that an extremely large reflecting area can be created – allowing for higher efficiency and greater control in both up and down axes of the fixture. Lamp holders are selected and lamps are roughly positioned in the 3d space available in the conceptual design. Initially the fixture is worked on as 2 designs – an up light and a down light. Cutoff and efficiency are considered and a simple sketch of a possible reflector solution for each is created.
7	Photopia optical design and photometric modeling - Lamps The Pro/Engineer 2d And 3d CAD files are imported into Photopia. Photopia has a library of standard lamp and LED models which are placed into the lamp holders in the fixture – initially one lamp at a time – up then down components. If the particular lamp is not available in the library (rarely happens in architectural lighting), we make a digital model of the lamp which is combined with the IES file for the lamp. When we work in the entertainment industry we frequently have to have the lamp modeled and the lamp tested by a recognized lamp. (We recently designed a system using an 18,000 Watt HID lamp for a film and video company – the ballast weighed 800 Lbs! Most commercial lamps and LEDs are available from the lamp library supplied with Photopia.
8	Photopia optical design and photometric modeling - reflectors Photopia will accurately determine filament and lamp image resulting from each filament type and construction. It is possible to model reflector facets, refractor forms and diffuser types to aid removal of filament image in distributions. Accurately measured reflector surfaces are available from multiple manufacturers and also as standard painted surfaces . Peens and facets can be modeled within the program or created externally and imported. The software accurately predicts performance of standard and special reflector materials. One of our proprietary high reflectivity specular anodic coatings is shown here alongside a digitally modeled peen pattern.
9	Photopia optical design and photometric modeling - refractors In this Refractor design for Color Kinetics Inc., an extruded Fresnel lens converts the LED light distribution from 120 degrees to a narrow 30 degree distribution. Light rays can be seen being turned by the refractor. Numeric and shaded representations of output can be generated. In particular filament and lamp image are detected and designed out of the system. The element was subsequently prototyped in a clear rapid prototype plastic before tooling was undertaken.
10	Photopia optical design and photometric modeling - integration
11	Photopia optical design and photometric modeling – diffusion and control Series of light control accessories developed for Zumtobel Staff Lighting Inc. for a museum grade track lighting system. Photopia has a library of standard diffuse materials. Custom materials can be tested and imported into the library for analysis. Alternate materials can be applied to designs to determine the best light control solution – in this example alternate diffusion mediums, refractive spread lenses, light control louvers with specular and matte finish were evaluated. This enables accessories to be catalogued without test / manufacture – the light output from each option being reflected in the digitally generated IES files and photometric charts. A similar process was useed on the Altman Stage Lighting MR16 fixture at bottom right.
12	Photopia optical design and photometric modeling – real world results
13	Photopia optical design and photometric modeling – diffusion and control Once the initial design is developed it is relatively simple to adjust to lamp positions and scale reflectors to create IES files for a whole line of product. As here in a line voltage track line by Altman Stage Lighting. Sometimes Photopia will lead you in a new direction to discover something that you never expected existed – like this unusually shaped and patent applied for HID wall wash fixture.
14	STYLE SELECTED – OPTICAL DESIGN COMPLETED In our original example 2 reflector profiles were developed, then exported back into Pro/Engineer to be joined together. After joining, the combined part is bourght back into Photopia and a full photometric test is run with both lamps in place and in a “real” room with a ceiling in place. In the images below you can see light rays exiting an invisible lamp and reflector system, the up component then bouncing back from the ceiling.
15	STYLE SELECTED – OPTICAL DESIGN OUTPUT The accuracy of results generated depends upon how long you let the computer run the test for. The longer, the more accurate and the more likely it is that you will be able to see problems in distribution. Candela and footcandle plots are generated.
16	OPTICAL DESIGN PHOTOMETRIC FILE OUTPUT The photometric file for the fixture follows this page. In the page following that you will see the content of a typical IES format file for use in AGI32 etc.
17	OPTICAL DESIGN PHOTOMETRIC FILE OUTPUT – IES FORMAT – 1 IESNA:LM-63-1995 [TEST] Photopia 1.5.0.22 PHOTOMETRIC REPORT [MANUFAC] productswithpassion [LUMINAIRE] dWave [LUMCAT] second_combined_forcandela [_FIXTURE] Extruded plastic housing [DATE] FEB-02 [MORE] 2 LAMPS - HO [LAMPCAT] F54T5HO [_LAMPLUM] 5000 [BALLAST] ELECTRONIC [_ALIGN] SYMMETRIC--0 degree plane parallel to lamps TILT=NONE [_WATT] 100 NUBER OF LAMPS = 2 0.00 22.50 45.00 67.50 90.00 112.50 135.00 157.50 180.00 202.50 0.00 1196 1196 1196 1196 1196 1196 1196 1196 1196 1196 5.00 1180 1183 1195 1169 1190 1195 1184 1166 1239 1203 10.00 1199 1231 1188 1175 1142 1171 1186 1205 1208 1211 15.00 1232 1226 1202 1143 1155 1133 1190 1243 1244 1251 20.00 1261 1253 1190 1145 1113 1129 1212 1264 1276 1250 25.00 1250 1237 1183 1111 1076 1127 1225 1252 1266 1252 30.00 1209 1188 1153 1059 1021 1082 1168 1206 1211 1198 35.00 1166 1138 1091 1001 934 1010 1100 1159 1196 1176 40.00 1091 1083 1019 921 852 943 1049 1125 1152 1123 45.00 1002 992 945 852 769 868 990 1051 1078 1048 50.00 918 903 856 776 692 802 928 971 975 970 55.00 848 814 774 696 613 736 843 880 891 880 60.00 722 718 688 618 520 664 756 779 775 769 65.00 575 580 577 518 437 578 637 561 497 563 70.00 311 363 451 430 344 479 454 280 218 286 75.00 126 134 242 321 266 364 211 118 138 120 80.00 110 114 112 197 171 204 152 329 402 331 85.00 38.2 52.3 72.9 93.1 75.5 143 352 523 573 513 90.00 0.760 4.72 24.2 48.7 35.7 179 375 528 576 527 95.00 0.100 8.68 59.2 129 72.4 206 430 582 622 582 100.00 225 282 365 268 171 294 492 644 682 635 105.00 546 538 451 397 302 416 542 671 725 680 110.00 618 603 520 455 337 469 594 730 769 731 115.00 707 694 619 515 379 509 674 792 834 788 120.00 764 762 736 602 430 593 798 837 872 837 125.00 865 845 826 725 596 714 880 926 944 937 130.00 974 976 914 754 679 744 950 1059 1075 1054 135.00 1129 1096 985 772 725 755 1003 1185 1208 1172 140.00 1231 1210 1064 807 763 820 1037 1244 1299 1234 145.00 1293 1221 1087 913 861 923 1072 1230 1293 1234 150.00 1221 1188 1044 1002 967 989 1045 1149 1214 1148 155.00 1158 1101 1032 1004 991 1008 1024 1082 1144 1121 160.00 1114 1078 1039 1003 995 1020 1023 1077 1116 1085 165.00 1108 1045 1036 1009 1012 1009 1023 1064 1089 1064 170.00 1077 1085 1062 1066 1041 1063 1021 1065 1078 1077 175.00 1094 1089 1089 1021 1104 1046 1075 1059 1094 1102 180.00 1060 1060 1060 1060 1060 1060 1060 1060 1060 1060
18	OPTICAL DESIGN PHOTOMETRIC FILE OUTPUT – IES FORMAT - 2
19	FINAL STAGES Once the design is completed, the individual parts of the fixture are sent out to our rapid prototype vendors. The process of rapid prototype stereolithography is well known in the industry. Multiple technologies now exist which can produce plastic, high temperature plastic and even sintered metal parts directly from our solid model files.