Simplified illustrations of visual and circadian pathways
Hypophysis - regulates daily and
seasonal circadian rhythms
Visual cortex
Pineal gland
Optic nerve
1-2 receptor rods and cones
Melatonin
Biologic nerve
3 receptor
Retina
Adrenal cortex
Cortisol
(spinal cord)
Visual Photopic lane
Biological lane
New study - the background luminance and colour
temperatures influence on alertness and mental health
Govén, Laike, Pendse, Sjöberg 2006
Purpose
”to lay down the
appropriate luminance
levels at different
colour temperatures
for ambient lighting
within working areas”
Februari
2007effect
- T.Govén,
Fagerhult
Science
studies
on lighting
design, Nov 2006 T.Govén
Methodology of the test
Fluorescent T5-tubes
3000K
Fluorescent
T5-tubes
3000K
Fluorescent
Fluorescent T5-tubes
T5-tubes 4000K
4000K
Lav 1 = 20 cd/m2
Lav 2 = 100 cd/m2
Lav 3 = 350 cd/m2
±30°
Eh=500
lx
±30°
36 subjects
Test room 1
Februari 2007 - T.Govén, Fagerhult
Test room 2
The Pickhurst study
Comparison in Cortisol on ground floor – C1 vs. E1
Cortisol
nmol/l
5,0
4,5
4,0
3,5
3,0
2,5
2,0
1,5
1,0
0,5
0
Ground floor
C1
Control room
E1
Experimental room
October
December
February
March
ANOVA Repeated measures
May
Comparison in Melatonin on ground floor – C1 vs. E1
Melatonin
pmol/l
7
6
5
4
3
2
1
0
Ground floor
C1
Control room
E1
Experimental room
October
November
December
January
Math
Grade
Progress
3,5
3,0
2,5
2,0
1,5
1,0
0,5
0
Dark season
Whole school year
C1
Control room
E1
Experimental room
C1
E1
C1
E1
Ground floor
Ground floor
2008 Sept – 2009 Jan
2008 Sept – 2009 May
Reading Grades
Grade
Progress
3,5
3,0
2,5
2,0
1,5
1,0
0,5
0
Dark season
Whole school year
C1
Control room
E1
Experimental room
C1
E1
C1
E1
Ground floor
Ground floor
2008 Sept – 2009 Jan
2008 Sept – 2009 May
Energy Consumption
70
60
50
40
30
20
10
0
Jan
Feb
Mar
Apr
Control room 1 (C1)
May
Jun
Jul
Aug
Experimental room 2 (E2)
Sept
Okt
Nov
Dec
Control room 2 (C2)
Our research about ambient lighting, light and health
Does ambient
light affect
learning?
Does pupils feel
and perform better
in indirect LED?
2013
Direct or
direct/indirect light?
2011
2009
2007
2001
!
2002
Vertical light – does
levels and colour
temperature matter?
The third
receptor!
Vertical light –
LED or T5?
Indira
Indirect/Wallwasher
Indira
Indirect/Wallwasher
Indira
Wallwasher
Visual
Biological
Emotional
Well Being
Your eye
What is the size of your eyeball?
Ø: 24mm
What is a solid angel?
0,5 Sr
Ø: 14mm
50cm
D: 40cm
Your eyeball from the side
0,5 Sr
Fovea
Ø: 14mm
Ganglion
cell area
Your eyeball from the front
0,5 Sr
Ø: 14mm
Ganglion
cell area
View from my office
Horizontal reference line
Luminance view from my office
Horizontal reference line
View at my desk
My environment
Vertical reference line
< 0,5 Sr
< 0,1 Sr
Horizontal reference line
Luminance view at my desk
< 0,5 Sr
< 0,1 Sr
Evening view at my desk
Luminance evening view at my desk
< 0,5 Sr
< 0,1 Sr