904:
144:
47:
372:
484:
330:
The IEC 60825 series gives guidance on safety relating to exposure of the eye to lasers, which are high luminance sources. The IEC 62471 series gives guidance for evaluating the photobiological safety of lamps and lamp systems including luminaires. Specifically it specifies the exposure limits,
706:
1020:
331:
reference measurement technique and classification scheme for the evaluation and control of photobiological hazards from all electrically powered incoherent broadband sources of optical radiation, including LEDs but excluding lasers, in the wavelength range from
385:
859:
311:
is higher at the image. The light at the image plane, however, fills a larger solid angle so the luminance comes out to be the same assuming there is no loss at the lens. The image can never be "brighter" than the source.
607:
918:
326:
Retinal damage can occur when the eye is exposed to high luminance. Damage can occur because of local heating of the retina. Photochemical effects can also cause damage, especially at short wavelengths.
1135:
307:
equal to the input. As an example, if one uses a lens to form an image that is smaller than the source object, the luminous power is concentrated into a smaller area, meaning that the
789:
178:
travelling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected from a particular area, and falls within a given
2615:
2619:
479:{\displaystyle L_{\mathrm {v} }={\frac {\mathrm {d} ^{2}\Phi _{\mathrm {v} }}{\mathrm {d} \Sigma \,\mathrm {d} \Omega _{\Sigma }\cos \theta _{\Sigma }}}}
359:. The simplest devices measure the luminance in a single direction while imaging luminance meters measure luminance in a way similar to the way a
1174:
1085:
1207:
235:
194:
701:{\displaystyle L_{\mathrm {v} }={\frac {\mathrm {d} ^{2}\Phi _{\mathrm {v} }}{\mathrm {d} S\,\mathrm {d} \Omega _{S}\cos \theta _{S}}}}
2531:
1015:{\displaystyle \int _{\Omega _{\Sigma }}L_{\text{v}}\mathrm {d} \Omega _{\Sigma }\cos \theta _{\Sigma }=M_{\text{v}}=E_{\text{v}}R,}
1802:
190:
2508:
277:
Luminance is used in the video industry to characterize the brightness of displays. A typical computer display emits between
2597:
2361:
recommend that photometric quantities be denoted with a subscript "v" (for "visual") to avoid confusion with radiometric or
1729:
1144:
A variety of units have been used for luminance, besides the candela per square metre. Luminance is essentially the same as
1167:
216:
111:
2591:
83:
130:
2537:
1148:, the term used in astronomy. This is measured with a logarithmic scale, magnitudes per square arcsecond (MPSAS).
1714:
90:
2626:
1160:
300:. This means that for an ideal optical system, the luminance at the output is the same as the input luminance.
68:
1189:
270:
the surface will appear. In this case, the solid angle of interest is the solid angle subtended by the eye's
2550:
2646:
1795:
97:
339:. This standard was prepared as Standard CIE S 009:2002 by the International Commission on Illumination.
64:
35:
2330:
79:
1982:
1184:
380:
227:
379:
The luminance of a specified point of a light source, in a specified direction, is defined by the
1788:
1079:
57:
2358:
1734:
854:{\displaystyle L_{\mathrm {v} }=n^{2}{\frac {\mathrm {d} \Phi _{\mathrm {v} }}{\mathrm {d} G}}}
1075:
171:
8:
2641:
2346:
2305:
2271:
1897:
891:
352:
293:
163:
2470:
596:
If light travels through a lossless medium, the luminance does not change along a given
1927:
1719:
1709:
1145:
251:
167:
104:
2587:
2504:
2500:
2226:
2176:
2099:
2059:
1739:
1071:
1042:
577:
239:
2345:" are for length, time and luminous intensity respectively, not the symbols for the
2452:
297:
2577:
2448:
ISO/CIE 23539:2023 CIE TC 2-93 Photometry — The CIE system of physical photometry
1844:
741:
2495:
Dörband, Bernd; Gross, Herbert; Müller, Henriette (2012). Gross, Herbert (ed.).
2456:
1767:
1241:
360:
355:
that can measure the luminance in a particular direction and with a particular
903:
2635:
1888:
541:
516:
263:
255:
2527:
Safety of laser products - Part 1: Equipment classification and requirements
2525:
2219:
1904:
1864:
1859:
1750:
1744:
1249:
1201:
520:
503:
321:
223:
24:
20:
2446:
250:
Luminance is often used to characterize emission or reflection from flat,
2014:
1960:
1235:
1230:
1063:
912:
554:
356:
308:
204:
179:
152:
143:
28:
242:, which is equal to one candela per square centimetre or 10 kcd/m.
2420:
2310:
2114:
2005:
1761:
267:
231:
200:
2379:
2377:
2375:
2583:
1908:
597:
558:
259:
148:
46:
2372:
1755:
1220:
186:
2425:
CIE S 017:2020 ILV: International
Lighting Vocabulary, 2nd edition
2003:
source area. The candela per square metre is sometimes called the
1730:
Exposure value § EV as a measure of luminance and illuminance
786:
More generally, the luminance along a light ray can be defined as
2554:
1948:
1942:
1724:
872:
499:
2362:
875:
of an infinitesimally narrow beam containing the specified ray;
2291:
Luminous efficacy normalized by the maximum possible efficacy
573:
271:
175:
2499:. Vol. 5, Metrology of Optical Components and Systems.
2244:
2238:
2196:
2190:
1130:{\displaystyle L_{\text{v}}={\frac {E_{\text{v}}R}{\pi }}.}
303:
For real, passive optical systems, the output luminance is
371:
2035:
2029:
1022:
where the integral covers all the directions of emission
155:
indicate luminance levels per the bar on the right (cd/m)
2367:
USA Standard Letter
Symbols for Illuminating Engineering
911:
The luminance of a reflecting surface is related to the
2300:
217:
Objectivity (science) § Objectivity in measurement
2427:. CIE - International Commission on Illumination. 2020
544:
area (m) of the source containing the specified point;
1088:
921:
792:
610:
388:
2323:
1747:, the representation of luminance in a video monitor
907:
Comparison of photometric and radiometric quantities
2618:using a camera's exposure meter. Also available in
71:. Unsourced material may be challenged and removed.
2530:(in English, French, and Spanish) (3rd ed.).
2494:
1773:
1129:
1014:
853:
700:
527:in any direction contained inside the solid angle
478:
262:looking at a particular surface from a particular
2579:Introduction to Nonimaging Optics, Second Edition
2633:
230:(cd/m). A non-SI term for the same unit is the
2540:- Optical radiation safety and laser equipment
884:is the luminous flux carried by this beam; and
151:-type candle, imaged with a luminance camera;
1796:
1758:, radiometric quantity analogous to luminance
1168:
254:surfaces. Luminance levels indicate how much
2517:
2352:
2266:Ratio of luminous flux to power consumption
1999:Luminous flux per unit solid angle per unit
722:seen from the source inside the solid angle
236:Centimetre–gram–second system of units (CGS)
185:The procedure for conversion from spectral
1803:
1789:
1175:
1161:
898:
600:. As the ray crosses an arbitrary surface
2532:International Electrotechnical Commission
1879:The lumen second is sometimes called the
663:
561:) containing the specified direction; and
441:
131:Learn how and when to remove this message
1764:, the subjective impression of luminance
902:
370:
266:. Luminance is thus an indicator of how
142:
2634:
2575:
238:(which predated the SI system) is the
219:for the importance of this contrast).
1824:
1820:
1817:
1814:
1156:
375:Parameters for defining the luminance
2616:Estimating Luminance and Illuminance
2383:Alternative symbols sometimes seen:
215:luminance measurement standard (see
189:to luminance is standardized by the
69:adding citations to reliable sources
40:
1078:), the luminance is isotropic, per
281:. The sun has a luminance of about
13:
2399:for luminous efficacy of a source.
2329:The symbols in this column denote
1082:. Then the relationship is simply
975:
959:
955:
950:
932:
928:
841:
832:
827:
822:
799:
670:
665:
656:
647:
642:
631:
617:
468:
452:
448:
443:
438:
434:
425:
420:
409:
395:
342:
14:
2658:
2608:
740:is the infinitesimal solid angle
315:
2600:from the original on 2016-02-18.
2032:(= lumen per square metre)
1056:is the received illuminance; and
764:is the angle between the normal
45:
1774:Table of SI light-related units
1715:Orders of magnitude (luminance)
782:and the direction of the light.
56:needs additional citations for
2569:
2551:"e-ILV : Luminance meter"
2543:
2488:
2463:
2439:
2413:
1922:Luminous energy per unit time
366:
245:
1:
2406:
2153:lumen second per cubic metre
1945:(= lumen per steradian)
718:is the infinitesimal area of
2135:Time-integrated illuminance
604:, the luminance is given by
592:and the specified direction.
7:
2497:Handbook of Optical Systems
2457:10.25039/IS0.CIE.23539.2023
2369:USAS Z7.1-1967, Y10.18-1967
1703:
1070:In the case of a perfectly
10:
2665:
2534:. 2014-05-15. p. 220.
2218:Ratio of luminous flux to
319:
36:Luminance (disambiguation)
33:
18:
2365:quantities. For example:
2295:
2270:
2225:
2175:
2139:
2098:
2058:
2013:
1966:
1926:
1887:
1843:
1838:
1835:
1832:
1829:
1634:1 ⁄ 30.48 ⁄
1624:1 ⁄ 0.3048 ⁄
1616:
1569:
1508:
1447:
1400:
1333:
1264:
1248:
1246:
1240:
1234:
1229:
1219:
1217:
1200:
1183:
258:could be detected by the
2625:Autodesk Design Academy
2475:Lighting Design Glossary
2140:Luminous energy density
1987:cd/m (= lm/(sr⋅m))
1983:candela per square metre
1783:SI photometry quantities
1139:
381:mixed partial derivative
228:candela per square metre
19:Not to be confused with
2395:for luminous flux, and
2359:Standards organizations
2349:litre, tesla and joule.
2274:, luminous coefficient
2075:lumen per square metre
1959:Luminous flux per unit
1650:1 ⁄ 0.3048
899:Relation to illuminance
2627:Measuring Light Levels
2576:Chaves, Julio (2015).
2421:"luminance, 17-21-050"
1735:Lambertian reflectance
1131:
1016:
908:
855:
702:
480:
376:
363:records color images.
156:
2553:. CIE. Archived from
2387:for luminous energy,
2062:, luminous emittance
1132:
1017:
906:
856:
703:
481:
374:
320:Further information:
146:
2557:on 16 September 2017
1086:
1080:Lambert's cosine law
1076:Lambertian reflector
919:
790:
608:
553:is an infinitesimal
386:
351:is a device used in
279:50 and 300 cd/m
65:improve this article
34:For other uses, see
2647:Physical quantities
2272:Luminous efficiency
1811:
1153:
1152:Units of luminance
892:index of refraction
523:) leaving the area
16:Photometric measure
1928:Luminous intensity
1914:lm (= cd⋅sr)
1780:
1720:Diffuse reflection
1710:Relative luminance
1151:
1146:surface brightness
1127:
1012:
909:
851:
698:
498:is the luminance (
476:
377:
234:. The unit in the
211:impression of the
168:luminous intensity
157:
2614:A Kodak guide to
2523:IEC 60825-1:2014
2510:978-3-527-40381-3
2451:. ISO/CIE. 2023.
2319:
2318:
2227:Luminous efficacy
2177:Luminous efficacy
2100:Luminous exposure
2060:Luminous exitance
1891:, luminous power
1740:Lightness (color)
1701:
1700:
1683:10 ⁄ 0.3048
1670:10 ⁄ 0.3048
1657:10 ⁄ 0.3048
1122:
1112:
1096:
1072:diffuse reflector
1043:luminous exitance
1041:is the surface's
1003:
990:
946:
849:
696:
474:
226:for luminance is
141:
140:
133:
115:
2654:
2602:
2601:
2573:
2567:
2566:
2564:
2562:
2547:
2541:
2535:
2521:
2515:
2514:
2492:
2486:
2485:
2483:
2481:
2467:
2461:
2460:
2443:
2437:
2436:
2434:
2432:
2417:
2400:
2398:
2394:
2390:
2386:
2381:
2370:
2356:
2350:
2327:
2279:
2234:
2186:
2150:
2111:
2072:
2026:
1979:
1939:
1907:(= candela
1901:
1856:
1812:
1805:
1798:
1791:
1784:
1779:
1692:
1690:
1684:
1679:
1677:
1671:
1666:
1664:
1658:
1651:
1646:
1644:
1638:
1637:
1628:
1627:
1609:
1587:
1584:1 ⁄
1579:
1565:
1563:
1556:
1535:
1530:
1523:
1518:
1504:
1502:
1495:
1474:
1469:
1462:
1457:
1423:
1418:
1410:
1394:
1386:
1380:
1375:
1368:
1363:
1356:
1351:
1327:
1320:
1315:
1308:
1303:
1296:
1291:
1283:
1267:
1260:
1258:
1227:
1215:
1211:
1198:
1193:
1177:
1170:
1163:
1154:
1150:
1136:
1134:
1133:
1128:
1123:
1118:
1114:
1113:
1110:
1103:
1098:
1097:
1094:
1061:
1055:
1040:
1028:
1021:
1019:
1018:
1013:
1005:
1004:
1001:
992:
991:
988:
979:
978:
963:
962:
953:
948:
947:
944:
938:
937:
936:
935:
889:
883:
870:
860:
858:
857:
852:
850:
848:
844:
838:
837:
836:
835:
825:
819:
817:
816:
804:
803:
802:
781:
774:
763:
754:
747:
739:
728:
721:
717:
707:
705:
704:
699:
697:
695:
694:
693:
678:
677:
668:
659:
653:
652:
651:
650:
640:
639:
634:
627:
622:
621:
620:
603:
591:
587:
571:
552:
539:
533:
526:
514:
497:
485:
483:
482:
477:
475:
473:
472:
471:
456:
455:
446:
437:
431:
430:
429:
428:
418:
417:
412:
405:
400:
399:
398:
338:
334:
298:geometric optics
288:
286:
280:
136:
129:
125:
122:
116:
114:
73:
49:
41:
2664:
2663:
2657:
2656:
2655:
2653:
2652:
2651:
2632:
2631:
2611:
2606:
2605:
2594:
2586:. p. 679.
2574:
2570:
2560:
2558:
2549:
2548:
2544:
2524:
2522:
2518:
2511:
2503:. p. 326.
2493:
2489:
2479:
2477:
2469:
2468:
2464:
2445:
2444:
2440:
2430:
2428:
2419:
2418:
2414:
2409:
2404:
2403:
2396:
2392:
2388:
2384:
2382:
2373:
2357:
2353:
2328:
2324:
2315:
2277:
2232:
2182:
2179:(of radiation)
2149:
2143:
2110:
2104:
2094:from a surface
2071:
2065:
2025:
2019:
1978:
1972:
1951:(= lm/sr)
1938:
1932:
1900:
1894:
1855:
1849:
1845:Luminous energy
1822:
1810:
1809:
1782:
1776:
1706:
1688:
1686:
1685:
1682:
1675:
1673:
1672:
1669:
1662:
1660:
1659:
1656:
1652:
1649:
1642:
1640:
1639:
1635:
1633:
1629:
1625:
1623:
1611:
1607:
1588:
1585:
1580:
1577:
1561:
1559:
1558:
1554:
1533:
1531:
1528:
1521:
1519:
1516:
1500:
1498:
1497:
1493:
1472:
1470:
1467:
1460:
1458:
1455:
1442:
1421:
1419:
1416:
1411:
1408:
1395:
1392:
1387:
1384:
1378:
1376:
1373:
1366:
1364:
1361:
1354:
1352:
1349:
1328:
1325:
1318:
1316:
1313:
1306:
1304:
1301:
1294:
1292:
1289:
1284:
1281:
1265:
1256:
1254:
1253:
1225:
1224:
1213:
1212:
1205:
1196:
1194:
1187:
1181:
1142:
1109:
1105:
1104:
1102:
1093:
1089:
1087:
1084:
1083:
1074:(also called a
1059:
1054:
1048:
1039:
1033:
1027:
1023:
1000:
996:
987:
983:
974:
970:
958:
954:
949:
943:
939:
931:
927:
926:
922:
920:
917:
916:
901:
887:
882:
878:
865:
840:
839:
831:
830:
826:
821:
820:
818:
812:
808:
798:
797:
793:
791:
788:
787:
776:
773:
765:
762:
758:
749:
745:
738:
732:
727:
723:
719:
712:
689:
685:
673:
669:
664:
655:
654:
646:
645:
641:
635:
630:
629:
628:
626:
616:
615:
611:
609:
606:
605:
601:
589:
588:to the surface
586:
580:
570:
564:
551:
547:
537:
532:
528:
524:
513:
509:
496:
490:
467:
463:
451:
447:
442:
433:
432:
424:
423:
419:
413:
408:
407:
406:
404:
394:
393:
389:
387:
384:
383:
369:
349:luminance meter
345:
343:Luminance meter
336:
332:
324:
318:
284:
282:
278:
248:
166:measure of the
137:
126:
120:
117:
74:
72:
62:
50:
39:
32:
17:
12:
11:
5:
2662:
2661:
2650:
2649:
2644:
2630:
2629:
2623:
2610:
2609:External links
2607:
2604:
2603:
2593:978-1482206739
2592:
2568:
2542:
2516:
2509:
2487:
2462:
2438:
2411:
2410:
2408:
2405:
2402:
2401:
2371:
2351:
2321:
2320:
2317:
2316:
2314:
2313:
2308:
2303:
2297:
2293:
2292:
2289:
2284:
2282:
2280:
2275:
2268:
2267:
2264:
2247:
2241:
2235:
2230:
2229:(of a source)
2223:
2222:
2216:
2199:
2193:
2187:
2180:
2173:
2172:
2170:
2157:
2154:
2151:
2147:
2141:
2137:
2136:
2133:
2120:
2117:
2112:
2108:
2102:
2096:
2095:
2090:Luminous flux
2088:
2079:
2076:
2073:
2069:
2063:
2056:
2055:
2050:Luminous flux
2048:
2039:
2038:(= lm/m)
2033:
2027:
2023:
2017:
2011:
2010:
1997:
1988:
1985:
1980:
1976:
1970:
1964:
1963:
1957:
1952:
1946:
1940:
1936:
1930:
1924:
1923:
1920:
1915:
1912:
1902:
1896:
1892:
1885:
1884:
1877:
1868:
1862:
1857:
1853:
1847:
1841:
1840:
1837:
1834:
1831:
1827:
1826:
1823:
1819:
1816:
1808:
1807:
1800:
1793:
1785:
1781:
1775:
1772:
1771:
1770:
1768:Glare (vision)
1765:
1759:
1753:
1748:
1742:
1737:
1732:
1727:
1722:
1717:
1712:
1705:
1702:
1699:
1698:
1693:
1680:
1667:
1654:
1647:
1631:
1621:
1618:
1614:
1613:
1604:
1599:
1596:
1593:
1590:
1582:
1574:
1571:
1567:
1566:
1551:
1548:
1543:
1540:
1537:
1525:
1513:
1510:
1506:
1505:
1490:
1487:
1484:
1479:
1476:
1464:
1452:
1449:
1445:
1444:
1439:
1436:
1433:
1430:
1425:
1413:
1405:
1402:
1398:
1397:
1389:
1382:
1370:
1358:
1346:
1341:
1338:
1335:
1331:
1330:
1322:
1310:
1298:
1286:
1279:
1276:
1271:
1268:
1262:
1261:
1247:
1245:
1239:
1233:
1228:
1218:
1216:
1199:
1182:
1180:
1179:
1172:
1165:
1157:
1141:
1138:
1126:
1121:
1117:
1108:
1101:
1092:
1068:
1067:
1057:
1052:
1046:
1037:
1025:
1011:
1008:
999:
995:
986:
982:
977:
973:
969:
966:
961:
957:
952:
942:
934:
930:
925:
900:
897:
896:
895:
894:of the medium.
885:
880:
876:
847:
843:
834:
829:
824:
815:
811:
807:
801:
796:
784:
783:
769:
760:
756:
734:
730:
725:
692:
688:
684:
681:
676:
672:
667:
662:
658:
649:
644:
638:
633:
625:
619:
614:
594:
593:
584:
568:
562:
549:
545:
535:
530:
511:
507:
494:
470:
466:
462:
459:
454:
450:
445:
440:
436:
427:
422:
416:
411:
403:
397:
392:
368:
365:
361:digital camera
344:
341:
317:
316:Health effects
314:
306:
256:luminous power
247:
244:
139:
138:
53:
51:
44:
15:
9:
6:
4:
3:
2:
2660:
2659:
2648:
2645:
2643:
2640:
2639:
2637:
2628:
2624:
2621:
2617:
2613:
2612:
2599:
2595:
2589:
2585:
2581:
2580:
2572:
2556:
2552:
2546:
2539:
2533:
2529:
2528:
2520:
2512:
2506:
2502:
2498:
2491:
2476:
2472:
2466:
2458:
2454:
2450:
2449:
2442:
2426:
2422:
2416:
2412:
2380:
2378:
2376:
2368:
2364:
2360:
2355:
2348:
2344:
2340:
2336:
2332:
2326:
2322:
2312:
2309:
2307:
2304:
2302:
2299:
2298:
2294:
2290:
2288:
2285:
2283:
2281:
2276:
2273:
2269:
2265:
2263:
2259:
2255:
2251:
2248:
2246:
2242:
2240:
2236:
2231:
2228:
2224:
2221:
2217:
2215:
2211:
2207:
2203:
2200:
2198:
2194:
2192:
2188:
2185:
2181:
2178:
2174:
2171:
2169:
2165:
2161:
2158:
2155:
2152:
2146:
2142:
2138:
2134:
2132:
2128:
2124:
2121:
2118:
2116:
2113:
2107:
2103:
2101:
2097:
2093:
2089:
2087:
2083:
2080:
2077:
2074:
2068:
2064:
2061:
2057:
2054:on a surface
2053:
2049:
2047:
2043:
2040:
2037:
2034:
2031:
2028:
2022:
2018:
2016:
2012:
2008:
2007:
2002:
1998:
1996:
1992:
1989:
1986:
1984:
1981:
1975:
1971:
1969:
1965:
1962:
1958:
1956:
1953:
1950:
1947:
1944:
1941:
1935:
1931:
1929:
1925:
1921:
1919:
1916:
1913:
1910:
1906:
1903:
1899:
1893:
1890:
1889:Luminous flux
1886:
1882:
1878:
1876:
1872:
1869:
1866:
1863:
1861:
1858:
1852:
1848:
1846:
1842:
1828:
1813:
1806:
1801:
1799:
1794:
1792:
1787:
1786:
1778:
1769:
1766:
1763:
1760:
1757:
1754:
1752:
1749:
1746:
1743:
1741:
1738:
1736:
1733:
1731:
1728:
1726:
1723:
1721:
1718:
1716:
1713:
1711:
1708:
1707:
1697:
1694:
1681:
1668:
1655:
1648:
1632:
1622:
1619:
1615:
1605:
1603:
1600:
1597:
1594:
1591:
1583:
1575:
1572:
1568:
1552:
1549:
1547:
1544:
1541:
1538:
1526:
1514:
1511:
1507:
1491:
1488:
1485:
1483:
1480:
1477:
1465:
1453:
1450:
1446:
1440:
1437:
1434:
1431:
1429:
1426:
1414:
1406:
1403:
1399:
1390:
1383:
1371:
1359:
1347:
1345:
1342:
1339:
1336:
1332:
1323:
1311:
1299:
1287:
1280:
1277:
1275:
1272:
1269:
1263:
1251:
1243:
1237:
1232:
1222:
1209:
1203:
1191:
1186:
1178:
1173:
1171:
1166:
1164:
1159:
1158:
1155:
1149:
1147:
1137:
1124:
1119:
1115:
1106:
1099:
1090:
1081:
1077:
1073:
1065:
1058:
1051:
1047:
1044:
1036:
1032:
1031:
1030:
1009:
1006:
997:
993:
984:
980:
971:
967:
964:
940:
923:
915:it receives:
914:
905:
893:
886:
877:
874:
869:
864:
863:
862:
845:
813:
809:
805:
794:
780:
772:
768:
757:
753:
748:as seen from
743:
737:
731:
716:
711:
710:
709:
690:
686:
682:
679:
674:
660:
636:
623:
612:
599:
583:
579:
575:
567:
563:
560:
556:
546:
543:
542:infinitesimal
536:
522:
518:
517:luminous flux
508:
505:
501:
493:
489:
488:
487:
464:
460:
457:
414:
401:
390:
382:
373:
364:
362:
358:
354:
350:
340:
328:
323:
313:
310:
304:
301:
299:
295:
292:Luminance is
290:
275:
273:
269:
265:
264:angle of view
261:
257:
253:
243:
241:
237:
233:
229:
225:
220:
218:
214:
210:
206:
202:
198:
196:
192:
188:
183:
181:
177:
173:
169:
165:
161:
154:
150:
145:
135:
132:
124:
113:
110:
106:
103:
99:
96:
92:
89:
85:
82: –
81:
77:
76:Find sources:
70:
66:
60:
59:
54:This article
52:
48:
43:
42:
37:
30:
26:
22:
2578:
2571:
2559:. Retrieved
2555:the original
2545:
2526:
2519:
2496:
2490:
2478:. Retrieved
2474:
2465:
2447:
2441:
2429:. Retrieved
2424:
2415:
2366:
2354:
2342:
2338:
2334:
2325:
2286:
2261:
2257:
2253:
2249:
2220:radiant flux
2213:
2209:
2205:
2201:
2183:
2167:
2163:
2159:
2144:
2130:
2126:
2122:
2105:
2091:
2085:
2081:
2066:
2051:
2045:
2041:
2020:
2004:
2000:
1994:
1990:
1973:
1967:
1954:
1933:
1917:
1880:
1874:
1870:
1860:lumen second
1850:
1777:
1751:Lumen (unit)
1695:
1601:
1545:
1481:
1427:
1343:
1273:
1255:= 1 ⁄
1250:foot-lambert
1143:
1069:
1049:
1034:
910:
867:
785:
778:
770:
766:
751:
735:
714:
595:
581:
576:between the
565:
491:
378:
348:
346:
337:3000 nm
329:
325:
322:Laser safety
302:
291:
287:10 cd/m
276:
249:
221:
212:
208:
199:
184:
159:
158:
153:false colors
127:
118:
108:
101:
94:
87:
75:
63:Please help
58:verification
55:
25:Luminescence
21:Luma (video)
2561:20 February
2471:"Luminance"
2015:Illuminance
1961:solid angle
1576:10 ⁄
1527:10 ⁄
1515:10 ⁄
1466:10 ⁄
1454:10 ⁄
1415:10 ⁄
1064:reflectance
913:illuminance
555:solid angle
367:Formulation
357:solid angle
333:200 nm
309:illuminance
246:Description
180:solid angle
164:photometric
80:"Luminance"
29:Illuminance
2642:Photometry
2636:Categories
2407:References
2331:dimensions
2311:Radiometry
2306:Photometry
2296:See also:
2237:lumen per
2189:lumen per
2115:lux second
1762:Brightness
1443:≈ 0.09290
1407:1 ⁄
353:photometry
209:subjective
201:Brightness
121:April 2023
91:newspapers
2584:CRC Press
2001:projected
1968:Luminance
1909:steradian
1821:Dimension
1815:Quantity
1589:≈ 0.3183
1412:≈ 0.3183
1329:≈ 0.2919
1226:≡ blondel
1197:≡ lm/m/sr
1120:π
976:Σ
972:θ
968:
960:Σ
956:Ω
933:Σ
929:Ω
924:∫
828:Φ
742:subtended
687:θ
683:
671:Ω
643:Φ
598:light ray
469:Σ
465:θ
461:
453:Σ
449:Ω
439:Σ
421:Φ
294:invariant
289:at noon.
260:human eye
213:objective
172:unit area
160:Luminance
149:tea light
2620:PDF form
2598:Archived
2431:20 April
2052:incident
1756:Radiance
1704:See also
1653:≈ 10.76
1630:≈ 3.426
1612:≈ 929.0
1388:≈ 3.142
1285:≈ 3.142
1221:apostilb
335:through
207:for the
187:radiance
2480:Apr 13,
2341:" and "
2156:lm⋅s/m
2092:emitted
1943:candela
1839:Symbol
1833:Symbol
1725:Etendue
1687:≈ 1.076
1674:≈ 1.076
1661:≈ 1.076
1641:≈ 3.426
1581:≈ 3183
1560:≈ 9.290
1532:≈ 3.183
1520:≈ 3.183
1499:≈ 9.290
1471:≈ 3.183
1459:≈ 3.183
1448:1 bril
1441:0.3048
1420:≈ 3.183
1396:≈ 2919
1377:≈ 3.142
1365:≈ 3.142
1353:≈ 3.142
1324:0.3048
1317:≈ 3.142
1305:≈ 3.142
1293:≈ 3.142
1242:lambert
1214:≡ cd/cm
1062:is the
890:is the
873:etendue
871:is the
572:is the
515:is the
305:at most
252:diffuse
224:SI unit
203:is the
105:scholar
2590:
2507:
2363:photon
1881:talbot
1825:Notes
1606:0.3048
1553:0.3048
1492:0.3048
1401:1 asb
1391:30.48
1266:1 cd/m
1195:≡ nit
861:where
708:where
578:normal
540:is an
486:where
268:bright
107:
100:
93:
86:
78:
2538:TC 76
2501:Wiley
2347:units
2119:lx⋅s
2078:lm/m
1905:lumen
1836:Name
1830:Name
1818:Unit
1617:1 fL
1509:1 sk
1334:1 sb
1259:cd/ft
1238:(sk)
1223:(asb)
1210:unit)
1204:(sb)
1202:stilb
1192:unit)
1140:Units
755:; and
574:angle
272:pupil
240:stilb
176:light
162:is a
112:JSTOR
98:books
27:, or
2588:ISBN
2563:2013
2505:ISBN
2482:2009
2433:2023
2337:", "
2239:watt
2191:watt
1745:Luma
1570:1 L
1252:(fL)
1244:(L)
1236:skot
1231:bril
1185:cd/m
222:The
205:term
193:and
170:per
84:news
2453:doi
2391:or
2333:; "
2243:lm/
2195:lm/
2030:lux
2006:nit
1867:⋅s
1610:10
1598:10
1595:10
1592:10
1550:10
1542:10
1539:10
1536:10
1524:10
1489:10
1486:10
1478:10
1475:10
1463:10
1438:10
1435:10
1432:10
1424:10
1381:10
1372:10
1369:10
1360:10
1357:10
1348:10
1340:10
1321:10
1312:10
1309:10
1300:10
1297:10
1288:10
1278:10
1208:CGS
965:cos
775:to
744:by
680:cos
458:cos
296:in
283:1.6
232:nit
195:ISO
191:CIE
174:of
67:by
2638::
2596:.
2582:.
2536:-
2473:.
2423:.
2374:^
2301:SI
2036:lx
2009:.
1949:cd
1911:)
1883:.
1865:lm
1691:10
1678:10
1665:10
1645:10
1620:=
1573:=
1564:10
1557:10
1512:=
1503:10
1496:10
1451:=
1404:=
1337:=
1270:=
1190:SI
1029:,
879:dΦ
746:dΣ
733:dΩ
724:dΩ
590:dΣ
559:sr
548:dΩ
538:dΣ
529:dΩ
525:dΣ
521:lm
510:dΦ
506:);
500:cd
347:A
274:.
197:.
182:.
147:A
23:,
2622:.
2565:.
2513:.
2484:.
2459:.
2455::
2435:.
2397:ρ
2393:F
2389:P
2385:W
2343:J
2339:T
2335:L
2287:1
2278:V
2262:J
2260:⋅
2258:T
2256:⋅
2254:L
2252:⋅
2250:M
2245:W
2233:η
2214:J
2212:⋅
2210:T
2208:⋅
2206:L
2204:⋅
2202:M
2197:W
2184:K
2168:J
2166:⋅
2164:T
2162:⋅
2160:L
2148:v
2145:ω
2131:J
2129:⋅
2127:T
2125:⋅
2123:L
2109:v
2106:H
2086:J
2084:⋅
2082:L
2070:v
2067:M
2046:J
2044:⋅
2042:L
2024:v
2021:E
1995:J
1993:⋅
1991:L
1977:v
1974:L
1955:J
1937:v
1934:I
1918:J
1898:v
1895:Φ
1875:J
1873:⋅
1871:T
1854:v
1851:Q
1804:e
1797:t
1790:v
1696:1
1689:×
1676:×
1663:×
1643:×
1636:π
1626:π
1608:×
1602:1
1586:π
1578:π
1562:×
1555:×
1546:1
1534:×
1529:π
1522:×
1517:π
1501:×
1494:×
1482:1
1473:×
1468:π
1461:×
1456:π
1428:1
1422:×
1417:π
1409:π
1393:π
1385:π
1379:×
1374:π
1367:×
1362:π
1355:×
1350:π
1344:1
1326:π
1319:×
1314:π
1307:×
1302:π
1295:×
1290:π
1282:π
1274:1
1257:π
1206:(
1188:(
1176:e
1169:t
1162:v
1125:.
1116:R
1111:v
1107:E
1100:=
1095:v
1091:L
1066:.
1060:R
1053:v
1050:E
1045:;
1038:v
1035:M
1026:Σ
1024:Ω
1010:,
1007:R
1002:v
998:E
994:=
989:v
985:M
981:=
951:d
945:v
941:L
888:n
881:v
868:G
866:d
846:G
842:d
833:v
823:d
814:2
810:n
806:=
800:v
795:L
779:S
777:d
771:S
767:n
761:S
759:θ
752:S
750:d
736:S
729:;
726:Σ
720:S
715:S
713:d
691:S
675:S
666:d
661:S
657:d
648:v
637:2
632:d
624:=
618:v
613:L
602:S
585:Σ
582:n
569:Σ
566:θ
557:(
550:Σ
534:;
531:Σ
519:(
512:v
504:m
502:/
495:v
492:L
444:d
435:d
426:v
415:2
410:d
402:=
396:v
391:L
285:×
134:)
128:(
123:)
119:(
109:·
102:·
95:·
88:·
61:.
38:.
31:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
