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Lumen (unit)

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2105: 579:, which involves averaging together several measurements taken at different positions. For marketing purposes, the luminous flux of projectors that have been tested according to this procedure may be quoted in "ANSI lumens", to distinguish them from those tested by other methods. ANSI lumen measurements are in general more accurate than the other measurement techniques used in the projector industry. This allows projectors to be more easily compared on the basis of their brightness specifications. 595:. The testing uses a test pattern typically at either 10 and 20 percent of the image area as white at the center of the screen, the rest as black. The light output is measured just in this center area. Limitations with CRT video projectors result in them producing greater brightness when just a fraction of the image content is at peak brightness. For example, the Sony VPH-G70Q CRT video projector produces 1200 "peak" lumens but just 200 ANSI lumens. 2079: 2117: 583:
possible to distinguish between a 5% screen area block of 95% peak white, and two identically sized 100% and 90% peak white boxes at the center of the white field. The light output is then measured on a full white field at nine specific locations around the screen and averaged. This average is then multiplied by the screen area to give the brightness of the projector in "ANSI lumens".
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in terms of luminous flux (lm), instead of electric power (W). That change is a result of the EU's Eco-design Directive for Energy-using Products (EuP). For example, according to the European Union standard, an energy-efficient bulb that claims to be the equivalent of a 60 W tungsten bulb must
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The method for measuring ANSI lumens is defined in the IT7.215 document which was created in 1992. First the projector is set up to display an image in a room at a temperature of 25 °C (77 °F). The brightness and contrast of the projector are adjusted so that on a full white field, it is
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A source radiating a power of one watt of light in the color for which the eye is most efficient (a wavelength of 555 nm, in the green region of the optical spectrum) has luminous flux of 683 lumens. So a lumen represents at least 1/683 watts of visible light power, depending on the spectral
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is that the lux takes into account the area over which the luminous flux is spread. A flux of 1,000 lumens, concentrated into an area of one square metre, lights up that square metre with an illuminance of 1,000 lux. The same 1,000 lumens, spread out over ten square metres, produces a dimmer
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The lumen can be thought of casually as a measure of the total amount of visible light in some defined beam or angle, or emitted from some source. The number of candelas or lumens from a source also depends on its spectrum, via the nominal response of the human eye as represented in the
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one-candela light-source emits a total luminous flux of exactly 4π lumens. If the source were partly covered by an ideal absorbing hemisphere, that system would radiate half as much luminous flux—only 2π lumens. The
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emits about 1,400–1,600 lm. Many compact fluorescent lamps and other alternative light sources are labelled as being equivalent to an incandescent bulb with a specific
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The 9th edition of the SI Brochure gives cd⋅sr as the lumen expressed in terms of base units, although the steradian (sr) is itself listed as a derived unit.
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recommend that photometric quantities be denoted with a subscript "v" (for "visual") to avoid confusion with radiometric or
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Brightness (white light output) measures the total amount of light projected in lumens. The color brightness specification
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measures red, green, and blue each on a nine-point grid, using the same approach as that used to measure brightness.
2095: 1617: 2142: 1639: 1587: 2018: 819: 575:) is typically measured in lumens. A standardized procedure for testing projectors has been established by the 331: 2059: 625: 313: 299: 1763: 1195: 31: 338:. Below is a table that shows typical luminous flux for common incandescent bulbs and their equivalents. 327:
are commonly labelled with their light output in lumens; in many jurisdictions, this is required by law.
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https://www.amazon.com/PacLights-Ultra150-Performance-Equivalent-Replacement/dp/B00F9CM49Y
681: 572: 568: 148:) in that radiant flux includes all electromagnetic waves emitted, while luminous flux is 141: 312:
capable of producing 470 lumens. It consumes about one sixth the electrical power of an
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ISO/CIE 23539:2023, CIE TC 2-93, Photometry — The CIE system of physical photometry
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legislation came into force mandating that lighting equipment must be labelled
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would still be one candela in those directions that are not obscured.
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Philips Luxeon CoB emitters, specifically LHC1-4090-1211 datasheet
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Philips Luxeon CoB emitters, specifically LHC1-4090-1208 datasheet
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source area. The candela per square metre is sometimes called the
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Luminous efficacy normalized by the maximum possible efficacy
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To estimate lumens from watts for various types of lamp, see
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Peak lumens is a measure of light output normally used with
1748: 1374:"Lumens, Illuminance, Foot-candles and bright shiny beads…" 1137: 50: 1742: 1204:
USA Standard Letter Symbols for Illuminating Engineering
1614:"Energy-saving light bulbs: how to read the packaging" 2093: 1554:
http://www.philipslumileds.com/uploads/419/DS115-pdf
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http://www.philipslumileds.com/uploads/419/DS115-pdf
2037: 1959: 1834: 1786: 96: 74: 66: 56: 44: 39: 342:Electrical power equivalents for different lamps 203:, so a light source that uniformly radiates one 1437:. Energy Federation Incorporated. Archived from 207:in all directions has a total luminous flux of 1764: 1743:International Lighting Vocabulary 2nd Edition 1461:"Learn About Light Output : ENERGY STAR" 633: 278:illuminance of only 100 lux. Mathematically, 156:") of the human eye's sensitivity to various 8: 1103:Ratio of luminous flux to power consumption 836:Luminous flux per unit solid angle per unit 2055:Historical definitions of the SI base units 547:have a minimum light output of 700-810 lm. 1771: 1757: 1749: 640: 626: 616: 36: 1695:"ANSI method of light output measurement" 716:The lumen second is sometimes called the 227:of luminous intensity uniformly across a 27:SI derived unit of visible light emission 340: 239:emitted into that angle is one lumen (1 175:The lumen is defined in relation to the 160:; this weighting is standardized by the 2100: 1588:"Ecodesign for energy-using appliances" 1568:. England: National Physical Laboratory 1484:. The Lightbulb Company. 11 August 2016 1300: 1281: 1159: 1310:The International System of Units (SI) 132:, a measure of the perceived power of 1616:. European Commission. Archived from 1528:one example has been found, at URL: 1352:"Lesson introduction to solid angles" 661: 657: 654: 651: 577:American National Standards Institute 354:Electrical power consumption (watts) 7: 1220:Alternative symbols sometimes seen: 535:systems is 50–100 lumens per watt. 1594:. the EU institutions. Feb 2, 2010 1236:for luminous efficacy of a source. 1166:The symbols in this column denote 212:1 cd × 4π sr = 4π cd⋅sr ≈ 12.57 lm 25: 1566:"Lighting now labelled in lumens" 531:The typical luminous efficacy of 267:The difference between the units 140:(SI). Luminous flux differs from 78: 2115: 2103: 2078: 2077: 869:(= lumen per square metre) 247:= 1 lm). Alternatively, an 1671:. February 2004. Archived from 172:is one lumen per square metre. 2065:System of units of measurement 1399:"OSRAM Dulux Energisparepærer" 759:Luminous energy per unit time 1: 1482:"LED Light Bulb Buying Guide" 990:lumen second per cubic metre 782:(= lumen per steradian) 138:International System of Units 972:Time-integrated illuminance 223:If a light source emits one 136:emitted by a source, in the 1592:Summaries of EU legislation 1338:10.25039/IS0.CIE.23539.2023 1206:USAS Z7.1-1967, Y10.18-1967 2159: 1055:Ratio of luminous flux to 549: 293: 29: 2073: 1202:quantities. For example: 1132: 1107: 1062: 1012: 976: 935: 895: 850: 803: 763: 724: 680: 675: 672: 669: 666: 366: 363: 358: 353: 346: 316:producing the same light. 152:according to a model (a " 92: 2019:minute and second of arc 1644:PC Magazine Encyclopedia 977:Luminous energy density 824:cd/m (= lm/(sr⋅m)) 820:candela per square metre 620:SI photometry quantities 332:compact fluorescent lamp 2060:2019 revision of the SI 1232:for luminous flux, and 1196:Standards organizations 1186:litre, tesla and joule. 1111:, luminous coefficient 912:lumen per square metre 796:Luminous flux per unit 314:incandescent light bulb 300:Incandescent light bulb 2138:Units of luminous flux 1697:. 1993. Archived from 317: 32:Lumen (disambiguation) 1224:for luminous energy, 899:, luminous emittance 538:On 1 September 2010, 307: 1961:Other accepted units 1704:on February 26, 2012 1675:on September 3, 2006 1640:"ANSI lumen article" 1508:www.westinghouse.com 611:SI photometric units 593:CRT video projectors 567:The light output of 533:fluorescent lighting 364:Compact fluorescent 195:A full sphere has a 30:For other uses, see 2045:Conversion of units 1724:"Sony G70 Brochure" 1435:"Conventional CFLs" 1109:Luminous efficiency 648: 343: 262:luminosity function 154:luminosity function 87:... is equal to ... 1838:with special names 1372:Bryant, Robert H. 765:Luminous intensity 751:lm (= cd⋅sr) 617: 605:Color Light Output 599:Color light output 341: 318: 254:luminous intensity 106:    98:    2091: 2090: 1969:astronomical unit 1665:"Projector Guide" 1332:. ISO/CIE. 2023. 1260:Luminous efficacy 1156: 1155: 1064:Luminous efficacy 1014:Luminous efficacy 937:Luminous exposure 897:Luminous exitance 728:, luminous power 552:luminous efficacy 529: 528: 128:) is the unit of 118: 117: 75:Conversions 16:(Redirected from 2150: 2143:SI derived units 2120: 2119: 2108: 2107: 2099: 2081: 2080: 1773: 1766: 1759: 1750: 1731: 1730: 1728: 1720: 1714: 1713: 1711: 1709: 1703: 1691: 1685: 1684: 1682: 1680: 1661: 1655: 1654: 1652: 1650: 1636: 1630: 1629: 1627: 1625: 1610: 1604: 1603: 1601: 1599: 1584: 1578: 1577: 1575: 1573: 1562: 1556: 1550: 1544: 1538: 1532: 1526: 1520: 1519: 1517: 1515: 1500: 1494: 1493: 1491: 1489: 1478: 1472: 1471: 1469: 1468: 1463:. Energystar.gov 1457: 1451: 1450: 1448: 1446: 1431: 1425: 1424: 1422: 1420: 1415:on March 1, 2012 1414: 1408:. Archived from 1403: 1395: 1389: 1388: 1386: 1384: 1369: 1363: 1362: 1360: 1358: 1348: 1342: 1341: 1324: 1318: 1317: 1315: 1305: 1289: 1286: 1237: 1235: 1231: 1227: 1223: 1218: 1207: 1193: 1187: 1164: 1116: 1071: 1023: 987: 948: 909: 863: 816: 776: 744:(= candela 738: 693: 649: 642: 635: 628: 621: 573:video projectors 558:Projector output 344: 281: 213: 107: 99: 37: 21: 2158: 2157: 2153: 2152: 2151: 2149: 2148: 2147: 2128: 2127: 2126: 2114: 2102: 2094: 2092: 2087: 2069: 2050:Metric prefixes 2033: 1955: 1837: 1830: 1782: 1777: 1739: 1734: 1726: 1722: 1721: 1717: 1707: 1705: 1701: 1693: 1692: 1688: 1678: 1676: 1663: 1662: 1658: 1648: 1646: 1638: 1637: 1633: 1623: 1621: 1620:on 28 June 2013 1612: 1611: 1607: 1597: 1595: 1586: 1585: 1581: 1571: 1569: 1564: 1563: 1559: 1551: 1547: 1539: 1535: 1527: 1523: 1513: 1511: 1504:"Halogen lamps" 1502: 1501: 1497: 1487: 1485: 1480: 1479: 1475: 1466: 1464: 1459: 1458: 1454: 1444: 1442: 1433: 1432: 1428: 1418: 1416: 1412: 1401: 1397: 1396: 1392: 1382: 1380: 1371: 1370: 1366: 1356: 1354: 1350: 1349: 1345: 1326: 1325: 1321: 1313: 1307: 1306: 1302: 1298: 1293: 1292: 1287: 1283: 1278: 1246: 1241: 1240: 1233: 1229: 1225: 1221: 1219: 1210: 1194: 1190: 1165: 1161: 1152: 1114: 1069: 1019: 1016:(of radiation) 986: 980: 947: 941: 931:from a surface 908: 902: 862: 856: 815: 809: 788:(= lm/sr) 775: 769: 737: 731: 692: 686: 682:Luminous energy 659: 647: 646: 619: 613: 601: 589: 565: 560: 555: 302: 292: 279: 221: 211: 105: 97: 35: 28: 23: 22: 15: 12: 11: 5: 2156: 2154: 2146: 2145: 2140: 2130: 2129: 2125: 2124: 2112: 2089: 2088: 2086: 2085: 2074: 2071: 2070: 2068: 2067: 2062: 2057: 2052: 2047: 2041: 2039: 2035: 2034: 2032: 2031: 2026: 2021: 2016: 2011: 2006: 2001: 1996: 1991: 1986: 1981: 1976: 1971: 1965: 1963: 1957: 1956: 1954: 1953: 1948: 1943: 1938: 1933: 1928: 1923: 1918: 1913: 1908: 1903: 1898: 1893: 1888: 1883: 1878: 1873: 1868: 1863: 1858: 1856:degree Celsius 1853: 1848: 1842: 1840: 1836:Derived units 1832: 1831: 1829: 1828: 1823: 1818: 1813: 1808: 1803: 1798: 1792: 1790: 1784: 1783: 1778: 1776: 1775: 1768: 1761: 1753: 1747: 1746: 1738: 1737:External links 1735: 1733: 1732: 1715: 1686: 1656: 1631: 1605: 1579: 1557: 1545: 1533: 1521: 1510:. Westinghouse 1495: 1473: 1452: 1426: 1390: 1364: 1343: 1319: 1299: 1297: 1294: 1291: 1290: 1280: 1279: 1277: 1274: 1273: 1272: 1267: 1262: 1257: 1252: 1245: 1242: 1239: 1238: 1208: 1188: 1158: 1157: 1154: 1153: 1151: 1150: 1145: 1140: 1134: 1130: 1129: 1126: 1121: 1119: 1117: 1112: 1105: 1104: 1101: 1084: 1078: 1072: 1067: 1066:(of a source) 1060: 1059: 1053: 1036: 1030: 1024: 1017: 1010: 1009: 1007: 994: 991: 988: 984: 978: 974: 973: 970: 957: 954: 949: 945: 939: 933: 932: 927:Luminous flux 925: 916: 913: 910: 906: 900: 893: 892: 887:Luminous flux 885: 876: 875:(= lm/m) 870: 864: 860: 854: 848: 847: 834: 825: 822: 817: 813: 807: 801: 800: 794: 789: 783: 777: 773: 767: 761: 760: 757: 752: 749: 739: 733: 729: 722: 721: 714: 705: 699: 694: 690: 684: 678: 677: 674: 671: 668: 664: 663: 660: 656: 653: 645: 644: 637: 630: 622: 618: 612: 609: 600: 597: 588: 585: 564: 561: 559: 556: 540:European Union 527: 526: 523: 520: 518: 515: 511: 510: 507: 504: 502: 499: 495: 494: 491: 488: 486: 483: 479: 478: 475: 472: 469: 466: 462: 461: 458: 455: 452: 449: 445: 444: 441: 438: 436: 433: 429: 428: 425: 422: 419: 416: 412: 411: 408: 405: 403: 400: 396: 395: 392: 389: 386: 383: 379: 378: 375: 371: 370: 365: 362: 356: 355: 352: 330:A 23 W spiral 291: 288: 286:distribution. 220: 217: 216: 215: 193: 192: 116: 115: 103: 94: 93: 90: 89: 84: 77: 76: 72: 71: 68: 64: 63: 58: 54: 53: 48: 42: 41: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 2155: 2144: 2141: 2139: 2136: 2135: 2133: 2123: 2118: 2113: 2111: 2106: 2101: 2097: 2084: 2076: 2075: 2072: 2066: 2063: 2061: 2058: 2056: 2053: 2051: 2048: 2046: 2043: 2042: 2040: 2036: 2030: 2027: 2025: 2022: 2020: 2017: 2015: 2012: 2010: 2007: 2005: 2002: 2000: 1997: 1995: 1992: 1990: 1989:degree of arc 1987: 1985: 1982: 1980: 1977: 1975: 1972: 1970: 1967: 1966: 1964: 1962: 1958: 1952: 1949: 1947: 1944: 1942: 1939: 1937: 1934: 1932: 1929: 1927: 1924: 1922: 1919: 1917: 1914: 1912: 1909: 1907: 1904: 1902: 1899: 1897: 1894: 1892: 1889: 1887: 1884: 1882: 1879: 1877: 1874: 1872: 1869: 1867: 1864: 1862: 1859: 1857: 1854: 1852: 1849: 1847: 1844: 1843: 1841: 1839: 1833: 1827: 1824: 1822: 1819: 1817: 1814: 1812: 1809: 1807: 1804: 1802: 1799: 1797: 1794: 1793: 1791: 1789: 1785: 1781: 1774: 1769: 1767: 1762: 1760: 1755: 1754: 1751: 1744: 1741: 1740: 1736: 1725: 1719: 1716: 1700: 1696: 1690: 1687: 1674: 1670: 1666: 1660: 1657: 1645: 1641: 1635: 1632: 1619: 1615: 1609: 1606: 1593: 1589: 1583: 1580: 1567: 1561: 1558: 1555: 1549: 1546: 1543: 1537: 1534: 1531: 1525: 1522: 1509: 1505: 1499: 1496: 1483: 1477: 1474: 1462: 1456: 1453: 1441:on 2008-10-14 1440: 1436: 1430: 1427: 1411: 1407: 1400: 1394: 1391: 1379: 1378:The LED Light 1375: 1368: 1365: 1353: 1347: 1344: 1339: 1335: 1331: 1330: 1323: 1320: 1312: 1311: 1304: 1301: 1295: 1285: 1282: 1275: 1271: 1268: 1266: 1263: 1261: 1258: 1256: 1253: 1251: 1250:André Blondel 1248: 1247: 1243: 1217: 1215: 1213: 1209: 1205: 1201: 1197: 1192: 1189: 1185: 1181: 1177: 1173: 1169: 1163: 1160: 1149: 1146: 1144: 1141: 1139: 1136: 1135: 1131: 1127: 1125: 1122: 1120: 1118: 1113: 1110: 1106: 1102: 1100: 1096: 1092: 1088: 1085: 1083: 1079: 1077: 1073: 1068: 1065: 1061: 1058: 1054: 1052: 1048: 1044: 1040: 1037: 1035: 1031: 1029: 1025: 1022: 1018: 1015: 1011: 1008: 1006: 1002: 998: 995: 992: 989: 983: 979: 975: 971: 969: 965: 961: 958: 955: 953: 950: 944: 940: 938: 934: 930: 926: 924: 920: 917: 914: 911: 905: 901: 898: 894: 891:on a surface 890: 886: 884: 880: 877: 874: 871: 868: 865: 859: 855: 853: 849: 845: 844: 839: 835: 833: 829: 826: 823: 821: 818: 812: 808: 806: 802: 799: 795: 793: 790: 787: 784: 781: 778: 772: 768: 766: 762: 758: 756: 753: 750: 747: 743: 740: 736: 730: 727: 726:Luminous flux 723: 719: 715: 713: 709: 706: 703: 700: 698: 695: 689: 685: 683: 679: 665: 650: 643: 638: 636: 631: 629: 624: 623: 615: 610: 608: 606: 598: 596: 594: 586: 584: 580: 578: 574: 570: 562: 557: 553: 548: 545: 541: 536: 534: 524: 521: 519: 516: 513: 512: 508: 505: 503: 500: 497: 496: 492: 489: 487: 484: 481: 480: 476: 473: 470: 467: 464: 463: 459: 456: 453: 450: 447: 446: 442: 439: 437: 434: 431: 430: 426: 423: 420: 417: 414: 413: 409: 406: 404: 401: 398: 397: 393: 390: 387: 384: 381: 380: 376: 373: 372: 369: 361: 357: 350: 345: 339: 337: 333: 328: 326: 322: 315: 311: 306: 301: 297: 289: 287: 283: 280:1 lx = 1 lm/m 276: 275: 270: 265: 263: 257: 255: 250: 246: 242: 238: 237:luminous flux 234: 230: 226: 218: 210: 209: 208: 206: 202: 198: 190: 186: 182: 181: 180: 178: 173: 171: 167: 163: 159: 155: 151: 147: 143: 139: 135: 134:visible light 131: 130:luminous flux 127: 123: 114: 110: 104: 102: 101:SI base units 95: 91: 88: 85: 83: 79: 73: 69: 65: 62: 61:luminous flux 59: 55: 52: 49: 47: 43: 38: 33: 19: 1994:electronvolt 1890: 1718: 1706:. 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Retrieved 1346: 1328: 1322: 1309: 1303: 1284: 1203: 1191: 1179: 1175: 1171: 1162: 1123: 1098: 1094: 1090: 1086: 1057:radiant flux 1050: 1046: 1042: 1038: 1020: 1004: 1000: 996: 981: 967: 963: 959: 942: 928: 922: 918: 903: 888: 882: 878: 857: 841: 837: 831: 827: 810: 791: 770: 754: 741: 717: 711: 707: 701: 697:lumen second 687: 614: 602: 590: 581: 566: 543: 537: 530: 374:Non-halogen 360:Incandescent 349:light output 329: 319: 284: 272: 268: 266: 258: 235:, the total 222: 194: 174: 146:radiant flux 125: 121: 119: 86: 81: 57:Unit of 1669:CPILive.net 1488:16 November 852:Illuminance 798:solid angle 587:Peak lumens 571:(including 563:ANSI lumens 229:solid angle 219:Explanation 197:solid angle 158:wavelengths 46:Unit system 2132:Categories 1788:Base units 1467:2012-07-15 1296:References 1270:Nit (unit) 1255:Brightness 1168:dimensions 1148:Radiometry 1143:Photometry 1133:See also: 1074:lumen per 1026:lumen per 952:lux second 569:projectors 294:See also: 201:steradians 80:1 lm 1931:steradian 1846:becquerel 1624:March 10, 1598:March 10, 1572:March 10, 838:projected 805:Luminance 746:steradian 658:Dimension 652:Quantity 544:primarily 351:(lumens) 323:used for 249:isotropic 233:steradian 183:1 lm = 1 124:(symbol: 2083:Category 2038:See also 1811:kilogram 1780:SI units 1514:10 March 1406:Osram.dk 1244:See also 889:incident 377:Halogen 347:Minimum 325:lighting 310:LED lamp 296:LED lamp 290:Lighting 150:weighted 2110:Physics 2096:Portals 1999:hectare 1984:decibel 1926:sievert 1921:siemens 1851:coulomb 1801:candela 1708:Jan 15, 1679:Dec 20, 1649:Dec 20, 1445:Dec 23, 1419:May 25, 1178:" and " 993:lm⋅s/m 929:emitted 780:candela 676:Symbol 670:Symbol 522:75–100 231:of one 225:candela 205:candela 177:candela 2122:Energy 2014:minute 1974:dalton 1916:radian 1911:pascal 1901:newton 1826:second 1806:kelvin 1796:ampere 1383:Oct 4, 1357:Oct 4, 1200:photon 718:talbot 662:Notes 514:4,000 506:49–75 498:3,100 493:24–30 490:30–52 482:2,400 477:14–17 474:24–28 465:1,600 460:10–16 457:18–20 448:1,100 440:13–15 199:of 4π 168:. One 82:in ... 67:Symbol 18:Lumens 2029:tonne 2024:neper 2009:litre 1951:weber 1936:tesla 1891:lumen 1886:katal 1881:joule 1876:hertz 1871:henry 1861:farad 1816:metre 1727:(PDF) 1702:(doc) 1413:(PDF) 1402:(PDF) 1314:(PDF) 1276:Notes 1184:units 956:lx⋅s 915:lm/m 742:lumen 673:Name 667:Name 655:Unit 525:40.5 443:8–12 424:9–11 336:power 321:Lamps 269:lumen 142:power 122:lumen 40:lumen 2004:hour 1946:watt 1941:volt 1866:gray 1821:mole 1710:2008 1681:2006 1651:2006 1626:2012 1600:2012 1574:2012 1516:2020 1490:2017 1447:2008 1421:2013 1385:2010 1359:2010 1174:", " 1076:watt 1028:watt 517:300 501:200 485:150 468:100 432:800 427:5–8 415:450 407:3–5 399:200 394:1–2 391:2–3 298:and 271:and 164:and 120:The 1979:day 1906:ohm 1896:lux 1334:doi 1265:Lux 1228:or 1170:; " 1080:lm/ 1032:lm/ 867:lux 843:nit 704:⋅s 509:32 471:72 454:53 451:75 435:60 421:29 418:40 402:25 385:15 382:90 368:LED 308:An 274:lux 243:·1 179:as 170:lux 166:ISO 162:CIE 2134:: 1667:. 1642:. 1590:. 1506:. 1404:. 1376:. 1211:^ 1138:SI 873:lx 846:. 786:cd 748:) 720:. 702:lm 410:3 388:6 282:. 264:. 245:sr 241:cd 189:sr 185:cd 126:lm 113:sr 109:cd 70:lm 51:SI 2098:: 1772:e 1765:t 1758:v 1729:. 1712:. 1683:. 1653:. 1628:. 1602:. 1576:. 1518:. 1492:. 1470:. 1449:. 1423:. 1387:. 1361:. 1340:. 1336:: 1234:ρ 1230:F 1226:P 1222:W 1180:J 1176:T 1172:L 1124:1 1115:V 1099:J 1097:⋅ 1095:T 1093:⋅ 1091:L 1089:⋅ 1087:M 1082:W 1070:η 1051:J 1049:⋅ 1047:T 1045:⋅ 1043:L 1041:⋅ 1039:M 1034:W 1021:K 1005:J 1003:⋅ 1001:T 999:⋅ 997:L 985:v 982:ω 968:J 966:⋅ 964:T 962:⋅ 960:L 946:v 943:H 923:J 921:⋅ 919:L 907:v 904:M 883:J 881:⋅ 879:L 861:v 858:E 832:J 830:⋅ 828:L 814:v 811:L 792:J 774:v 771:I 755:J 735:v 732:Φ 712:J 710:⋅ 708:T 691:v 688:Q 641:e 634:t 627:v 554:. 214:. 191:. 187:· 144:( 111:⋅ 34:. 20:)

Index

Lumens
Lumen (disambiguation)
Unit system
SI
luminous flux
SI base units
cd
sr
luminous flux
visible light
International System of Units
power
radiant flux
weighted
luminosity function
wavelengths
CIE
ISO
lux
candela
cd
sr
solid angle
steradians
candela
candela
solid angle
steradian
luminous flux
cd

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