139:
36:
260:
were conducted by
Lambert between 1755 and 1760, after he decided to write a treatise on light measurement. His interest in acquiring experimental data spanned several fields: optics, thermometry, pyrometry, hydrometry, and magnetics. This interest in experimental data and its analysis, so evident in
112:
by some specific amount (things that could be directly measured, such as angle or distance). In this way, Lambert quantified purely visual properties (such as luminous power, illumination, transparency, reflectivity) by relating them to physical parameters (such as distance, angle, radiant power, and
269:
not only indispensable for this quantification but also the indisputable sign of rigor. He used linear algebra and calculus extensively with matter-of-fact confidence that was uncommon in optical works of the time. On this basis, Photometria is certainly uncharacteristic of mid-18th century works.
268:
Lambert's book is also mathematical. Though he knew that the physical nature of light was unknown (it would be 150 years before the wave-particle duality was established) he was certain that light's interaction with materials and its effect on vision could be quantified. Mathematics was for
Lambert
93:
In addition, Lambert postulated a surface that emits light (either as a source or by reflection) in a way such that the density of emitted light (luminous intensity) varies as the cosine of the angle measured from the surface perpendicular. In the case of a reflecting surface, this form of emission
68:
was the first work to accurately identify most fundamental photometric concepts, assemble them into a coherent system of photometric quantities, define these quantities with a precision sufficient for mathematical statements, and build from them a system of photometric principles. These concepts,
146:. The vertical screen produces field EFDC illuminated by the single candle and adjacent field GFDB illuminated by two candles. The candle distances are changed until the brightness on either side of FD is the same. The relative illuminating power can then be determined from the candle distances.
349:
presented significant advances and it was, perhaps, for that very reason that its appearance was greeted with general indifference. The central optical question in the middle of the 18th century was: what is the nature of light? Lambert's work was not related to this issue at all and so
156:
Using visual photometry, Lambert presented the results of many experimental determinations of specular and diffuse reflectance, as well as the transmittance of panes of glass and lenses. Among the most ingenious experiments he conducted was to determine the reflectance of the
72:
Lambert began with two simple axioms: light travels in a straight line in a uniform medium and rays that cross do not interact. Like Kepler before him, he recognized that "laws" of photometry are simply consequences and follow directly from these two assumptions. In this way
265:, is also present in other articles and books Lambert produced. For his optics work, extremely limited equipment sufficed: a few panes of glass, convex and concave lenses, mirrors, prisms, paper and cardboard, pigments, candles, and the means to measure distances and angles.
136:, Lambert established and demonstrated the laws of photometry. He did this with visual photometry and to establish the uncertainties involved, described its approximate limits by determining how small a brightness difference the visual system could determine.
169:
Assuming diffuse surfaces and the three laws of photometry, Lambert used
Calculus to find the transfer of light between surfaces of various sizes, shapes, and orientations. He originated the concept of the per-unit transfer of flux between surfaces and in
113:
color). Today, this is known as "visual photometry." Lambert was among the first to accompany experimental measurements with estimates of uncertainties based on a theory of errors and what he experimentally determined as the limits of visual assessment.
376:
needed photometry. Fifty years after that, Illuminating
Engineering took up Lambert's results as the basis for lighting calculations that accompanied the great expanse of lighting early in the 20th century. Fifty years after that,
116:
Although previous workers had pronounced photometric laws 1 and 3, Lambert established the second and added the concept of perfectly diffuse surfaces. But more importantly, as Anding pointed out in his German translation of
215:
Assuming that the planets had diffusely reflective surfaces, Lambert attempted to determine the amount of their reflectance, given their relative brightness and known distance from the sun. A century later, Zöllner studied
121:, "Lambert had incomparably clearer ideas about photometry" and with them established a complete system of photometric quantities. Based on the three laws of photometry and the supposition of perfectly diffuse surfaces,
194:
Lambert measured his own pupil diameter by viewing it in a mirror. He measured the change in diameter as he viewed a larger or smaller part of a candle flame. This is the first known attempt to quantify
585:
VerzeichniĂ der BĂŒcher und
Instrumente, welche der verstorbene Königl. Ober-Baurath und Professor Herr Heinrich Lambert hinterlassen hat, und die den Meistbiethenden sollen verkauft werden. Berlin, 1778
174:
showed the closed form for many double, triple, and quadruple integrals which gave the equations for many different geometric arrangements of surfaces. Today, these fundamental quantities are called
104:
Lambert demonstrated these principles in the only way available at the time: by contriving often ingenious optical arrangements that could make two immediately adjacent luminous fields appear
315:
Maria
Jakobina Klett (1709â1795) was the owner of Eberhard Klett Verlag, one of the most important Augsburg âProtestant publishers.â She published many technical books, including Lambertâs
64:(transliterated phĂŽs, photos) = light, and ΌΔÏÏÎčα (transliterated metria) = measure. Lambertâs word has found its way into European languages as photometry, photometrie, and fotometria.
575:
Bopp, K., âJohann
Heinrich Lamberts Monatsbuch,â Abhandlungen der Königlich Bayerischen Akademie der Wissenshaften, Mathematisch-physikalische Klasse, XXVII. Band 6. Munich, 1916.
234:. By simultaneous transmission and reflection from a pane of glass, he superimposed the images of two different colored patches of paper and noted the resulting additive color.
242:
Assuming the sky was a luminous dome, Lambert calculated the illumination by skylight through a window, and the light occluded and interreflected by walls and partitions.
514:
94:
is assumed to be the case, regardless of the light's incident direction. Such surfaces are now referred to as "Perfectly
Diffuse" or "Lambertian". See:
327:'s survey of optics of 1772, âLambertâs Photometrieâ appears in the list of books not yet procured. Priestley makes a specific reference to
32:
quantities and principles; using them to measure the optical properties of materials, quantify aspects of vision, and calculate illumination.
730:
378:
527:
Zöllner, J.C.F., Photometrische
Untersuchungen mit Besonderer RĂŒcksicht auf die Physische Beschaffenheit der Himmelskörper, Leipzig, 1865.
280:
Lambert began conducting photometric experiments in 1755 and by August 1757 had enough material to begin writing. From the references in
354:
received no immediate systematic evaluation, and was not incorporated into the mainstream of optical science. The first appraisal of
673:
Yamauti, Z., âFurther study of
Geometrical Calculation of Illumination due to Light from Luminous Surface Sources of Simple Form,â
720:
108:(something that could only be determined by visual observation) when two physical quantities that produced the two fields were
138:
382:
183:
395:
301:
470:
Sheynin, O.B., âJ.H. Lambertâs work on probability,â Archive for History of Exact Sciences, vol. 7, 1971, pp. 244â256.
362:âs German translation of Priestleyâs 1772 survey of optics. An elaborate reworking and annotation appeared in 1777.
305:
284:
and the catalogue of his library auctioned after his death, it is clear that Lambert consulted the optical works of
35:
740:
735:
86:
Illuminance on a surface varies as the cosine of the incidence angle measured from the surface perpendicular, and
725:
207:
Using the laws of photometry and a great deal of geometry, Lambert calculated the times and depths of twilight.
702:
419:
99:
25:
368:
was not seriously evaluated and utilized until nearly a century after its publication, when the science of
745:
424:
196:
95:
651:
Karsten, W.J.G., Lehrbegrif der gesamten Mathematic; Der Achte Theil, Die Photometrie, Greifswald, 1777.
390:
408:
359:
750:
29:
629:, Translated from the Latin by David L. DiLaura. New York, Illuminating Engineering Society, 2001.
323:. Its first and only printing was small, and within 10 years copies were difficult to obtain. In
297:
689:
584:
179:
324:
640:
Geschichte und gegenwÀrtiger zustand der Optik nach der Englischen Priestelys bearbeitet
611:
PhotomĂ©trie ou de la Mesure et de la Gradation de la lumiĂšre, des couleurs et de lâOmbre
319:, and 10 of his other works. Klett used Christoph Peter Detleffsen (1731â1774) to print
83:
Illuminance varies inversely as the square of the distance from a point source of light,
414:
293:
289:
231:
55:
444:
714:
622:
492:
Ariotti, P.E. and Marcolongo, F.J., "The Law of Illumination before Bouguer (1720)",
389:
had a significant, though long-delayed influence on technology and commerce once the
338:
appeared in 1892, a French translation in 1997, and an English translation in 2000.
598:
The History and Present State of Discoveries relating to Vision, Light, and Colours
373:
285:
312:
in Augsburg in February 1760 and the printer had the book available by June 1760.
256:
Lambert's book is fundamentally experimental. The forty experiments described in
175:
660:
DiLaura, D.L., âLightâs Measure: A History of Industrial Photometry to 1909,â
222:
and picked up where Lambert left off, and initiated the field of astrophysics.
459:
The Principles of Physical Optics: An Historical and Philosophical Treatment
393:
was well underway, and is the reason that it was one of the books listed in
369:
479:
Gal, O. and Chen-Morris, R., "The Archaeology of the Inverse Square Law",
627:
Photometry, or, On the measure and gradations of light, colors, and shade
54:
Written in Latin, the title of the book is a word Lambert devised from
153:
2. Reflectance and transmittance of glass and other common materials
445:
Photometria, sive de mensura et gradibus luminis, colorum et umbrae
137:
34:
461:, trans. J.S. Anderson and A.F.A. Young, Dutton, New York, 1926.
59:
227:
7. Demonstration of additive color mixing and colorimetry
178:, Shape Factors, or Configuration Factors and are used in
28:
published in 1760. It established a complete system of
69:quantities, and principles are still in use today.
551:Pyrometrie oder vom MaaĂe des Feuers und der WĂ€rme
331:; that it was an important book but unprocurable.
89:Light decays exponentially in an absorbing medium.
166:3. Luminous radiative transfer between surfaces
230:Lambert was the first to record the results of
385:required to produce architectural renderings.
696:Ostwalds Klassiker der exakten Wissenschaften
675:Researches of the Electrotechnical Laboratory
515:Ostwalds Klassiker der exakten Wissenschaften
8:
411:(LambertâBeer law, BeerâLambertâBouguer law)
381:took up Lambert's results as the basis for
125:developed and demonstrated the following:
204:5. Atmospheric refraction and absorption
24:is a book on the measurement of light by
540:, Appleton, New York, 1879, pp. 109â139.
504:
502:
79:demonstrated (rather than assumed) that
435:
664:, Jan 2005, Vol 1, No. 3, pp. 75â149.
609:Boye, J., J. Couty, and M. Saillard,
142:An example of visual photometry from
7:
677:, no., 194, Tokyo, 1927, n. 1, p. 3.
564:The Rise of the Wave Theory of Light
334:An abridged German translation of
14:
448:, Augsburg: Eberhard Klett, 1760.
483:, Vol 43, Dec. 2005 pp. 391â414.
129:1. Just noticeable differences
16:Book by Johann Heinrich Lambert
1:
642:, Leipsig, 1776, pp. 312â327.
191:4. Brightness and pupil size
496:, Vol. 33, No.4, pp 331â340.
396:Printing and the Mind of Man
239:8. Daylighting calculations
731:18th-century books in Latin
613:, LâHarmattan, Paris, 1997.
518:, Engelmann, Leipzig, 1892.
161:surface of a pane of glass.
767:
698:, Engelmann, Leipzig, 1892
442:Lambert, Johann Heinrich,
273:Writing and publishing of
60:
212:6. Astronomic photometry
306:Abraham Gotthelf KĂ€stner
132:In the first section of
39:Title page of Lambert's
706:, Klett, Augsburg, 1760
180:radiative heat transfer
26:Johann Heinrich Lambert
721:1760 non-fiction books
425:Lambertian reflectance
383:radiosity calculations
197:pupillary light reflex
147:
96:Lambertian reflectance
43:
566:, Chicago, 1989, p. 3
510:Lambertâs Photometrie
391:Industrial Revolution
232:additive color mixing
141:
38:
512:, No. 31, 32, 33 of
420:Lambert's cosine law
372:and the commerce of
358:appeared in 1776 in
694:No. 31, 32, 33 of
360:Georg Simon KlĂŒgel
298:Christiaan Huygens
148:
100:Lambertian emitter
44:
741:Mathematics books
736:Optical metrology
562:Buchwald, J. Z.,
538:Modern Chromatics
494:Annals of Science
379:computer graphics
184:computer graphics
758:
678:
671:
665:
658:
652:
649:
643:
636:
630:
620:
614:
607:
601:
594:
588:
582:
576:
573:
567:
560:
554:
547:
541:
534:
528:
525:
519:
506:
497:
490:
484:
477:
471:
468:
462:
455:
449:
440:
409:BeerâLambert law
325:Joseph Priestley
63:
62:
766:
765:
761:
760:
759:
757:
756:
755:
726:1760 in science
711:
710:
686:
681:
672:
668:
659:
655:
650:
646:
638:KlĂŒgel, G. S.,
637:
633:
621:
617:
608:
604:
595:
591:
583:
579:
574:
570:
561:
557:
553:, Berlin, 1779.
549:Lambert, J.H.,
548:
544:
535:
531:
526:
522:
507:
500:
491:
487:
481:History Science
478:
474:
469:
465:
456:
452:
441:
437:
433:
405:
344:
342:Later influence
278:
254:
52:
17:
12:
11:
5:
764:
762:
754:
753:
748:
743:
738:
733:
728:
723:
713:
712:
709:
708:
700:
685:
684:External links
682:
680:
679:
666:
653:
644:
631:
615:
602:
600:, London, 1772
596:Priestly, J.,
589:
577:
568:
555:
542:
529:
520:
498:
485:
472:
463:
450:
434:
432:
429:
428:
427:
422:
417:
415:lambert (unit)
412:
404:
401:
343:
340:
308:. He finished
294:Leonhard Euler
290:Pierre Bouguer
277:
271:
253:
247:
246:
245:
244:
243:
237:
236:
235:
225:
224:
223:
210:
209:
208:
202:
201:
200:
189:
188:
187:
164:
163:
162:
151:
150:
149:
106:equally bright
91:
90:
87:
84:
51:
45:
15:
13:
10:
9:
6:
4:
3:
2:
763:
752:
749:
747:
746:Physics books
744:
742:
739:
737:
734:
732:
729:
727:
724:
722:
719:
718:
716:
707:
705:
701:
699:
697:
693:
688:
687:
683:
676:
670:
667:
663:
657:
654:
648:
645:
641:
635:
632:
628:
624:
623:DiLaura, D.L.
619:
616:
612:
606:
603:
599:
593:
590:
586:
581:
578:
572:
569:
565:
559:
556:
552:
546:
543:
539:
533:
530:
524:
521:
517:
516:
511:
505:
503:
499:
495:
489:
486:
482:
476:
473:
467:
464:
460:
454:
451:
447:
446:
439:
436:
430:
426:
423:
421:
418:
416:
413:
410:
407:
406:
402:
400:
398:
397:
392:
388:
384:
380:
375:
371:
367:
363:
361:
357:
353:
348:
341:
339:
337:
332:
330:
326:
322:
318:
313:
311:
307:
303:
299:
295:
291:
287:
283:
276:
272:
270:
266:
264:
259:
252:
248:
241:
240:
238:
233:
229:
228:
226:
221:
220:
214:
213:
211:
206:
205:
203:
198:
193:
192:
190:
185:
181:
177:
173:
168:
167:
165:
160:
155:
154:
152:
145:
140:
135:
131:
130:
128:
127:
126:
124:
120:
114:
111:
107:
102:
101:
97:
88:
85:
82:
81:
80:
78:
77:
70:
67:
57:
50:
46:
42:
37:
33:
31:
27:
23:
22:
703:
695:
691:
674:
669:
661:
656:
647:
639:
634:
626:
618:
610:
605:
597:
592:
580:
571:
563:
558:
550:
545:
537:
532:
523:
513:
509:
508:Anding, E.,
493:
488:
480:
475:
466:
458:
453:
443:
438:
394:
386:
374:gas lighting
365:
364:
355:
351:
346:
345:
335:
333:
328:
320:
316:
314:
309:
302:Robert Smith
286:Isaac Newton
281:
279:
274:
267:
262:
257:
255:
250:
218:
217:
176:View Factors
171:
158:
143:
133:
122:
118:
115:
109:
105:
103:
92:
75:
74:
71:
65:
53:
48:
40:
20:
19:
18:
704:Photometria
692:Photometrie
536:Rood O.N.,
387:Photometria
366:Photometria
356:Photometria
352:Photometria
347:Photometria
336:Photometria
329:Photometria
321:Photometria
317:Photometria
310:Photometria
282:Photometria
275:Photometria
263:Photometria
258:Photometria
251:Photometria
219:Photometria
172:Photometria
144:Photometria
134:Photometria
123:Photometria
119:Photometria
76:Photometria
66:Photometria
49:Photometria
47:Content of
41:Photometria
30:photometric
21:Photometria
751:Photometry
715:Categories
457:Mach, E.,
431:References
249:Nature of
61:ÏῶÏ, ÏÏÏÎżÏ
690:Lamberts
370:astronomy
403:See also
159:interior
182:and in
110:unequal
662:LEUKOS
304:, and
56:Greek
717::
625:,
501:^
399:.
300:,
296:,
292:,
288:,
98:,
58::
587:.
199:.
186:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
