introduction to light pollution lecture 3rgn.hr/~zandreic/students/introlp/lp_en_p3.pdfŽeljko...
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Željko Andreić: Introduction to light pollution, P3 1
Introduction to Light Pollution
Lecture 3
prof. Željko Andreić
Faculty of Mining, Geology and Petroleum EngineeringUniversity of Zagreb
zandreic@rgn.hr
http://rgn.hr/~zandreic/
Željko Andreić: Introduction to light pollution, P3 2
Contents
1. sources of artificial light2. basic lamp characteristics3. "good" and "bad" lighting fixtures
Željko Andreić: Introduction to light pollution, P3 3
Street light
lighting fixture
pole
support
Željko Andreić: Introduction to light pollution, P3 4
Lighting fixture
case
support
protective glass
optics
control electronics
light bulb
Željko Andreić: Introduction to light pollution, P3 5
Tungsten light bulb
vacuum
filament
glass bulb
holder withelectrical contacts
Željko Andreić: Introduction to light pollution, P3 6
Fluorescent tube
rarefied noble gas
glass tube with phosporous coating inside
electrical contact
electrode
mercury
Željko Andreić: Introduction to light pollution, P3 7
High pressure vapour lamp
aluminaarc tube
holder withelectrical contacts
glass bulb
noble gas
alumina tube
electrode
volatile metal (Na,etc.)
Željko Andreić: Introduction to light pollution, P3 8
LED
LED crystal
transparent casing/lens
electrical contacts
Željko Andreić: Introduction to light pollution, P3 9
Polarn diagram of luminous intensity
90o-90o
180o
0o
Željko Andreić: Introduction to light pollution, P3 10
Usefull and useless light
Željko Andreić: Introduction to light pollution, P3 11
A very bad light fixture (luminaire)
Difuzna kugla sa žaruljom u sredini, 35% svjetla ide prema dolje a 40% prema gore!
Željko Andreić: Introduction to light pollution, P3 12
Prozirna kugla sa optikom i žaruljom u sredini, 58% svjetla ide prema dolje, a 17% prema gore
A bad light fixture
Željko Andreić: Introduction to light pollution, P3 13
Zatvorena lampa sa optikom, 68% svjetla ide prema dolje, ništa prema gore!
A good light fixture
Željko Andreić: Introduction to light pollution, P3 14
Very bad, bad, good...
opaque globe, 5m
transparent globe and optics, 5m
closed
luminiare, 8m
300 m road: 20x150 W = 3000 W
300 m road: 15x150 W = 2250 W
300 m road: 12x150 W = 1800 W
Željko Andreić: Introduction to light pollution, P3 15
How to reduce light pollution:
Bad Good
Željko Andreić: Introduction to light pollution, P3 16
Bad Good
How to reduce light pollution:
Željko Andreić: Introduction to light pollution, P3 17
Bad Good
How to reduce light pollution:
Željko Andreić: Introduction to light pollution, P3 18
Bad Good
How to reduce light pollution:
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