Technical information
6
C
eramic arc tubes can be
p
roduced with smaller
di
mens
i
ona
l
to
l
erances, re
d
uc
i
ng t
h
e var
i
at
i
on
i
n
li
g
h
t-
tec
h
n
i
ca
l
an
d
e
l
ectr
i
ca
l
parameters
.
C
eramic is less susceptible to attacks from the a
g-
g
ressive metal halide
f
illin
g
and is less permeable
f
or
f
illing particles, resulting in a considerably longe
r
service li
f
e com
p
ared to
q
uartz tube lam
p
s.
C
eramic arc tubes are now available in various different
f
orms: the ori
g
inal cylindrical version and the improved
r
ou
n
d
v
e
r
s
i
o
n
.
2
.
2
.1 1st
g
enerat
i
on: cy
li
n
d
r
i
ca
l
f
or
m
In the
f
irst version, the ceramic arc tube was desi
g
ned
in a c
y
lindrical
f
orm, based on the production technol-
o
g
y
f
or the hi
g
h-pressure sodium lamp. The arc tube
was made up o
f
c
y
lindrical sub-sections sintered to-
g
ether. The arc tube consisted o
f
a relatively thick plu
g
at either end o
f
the tube: this was necessar
y
f
or the
durability and
f
unctionin
g
o
f
the tube
.
2
.
2
.
2
2
n
d
g
enerat
i
on:
f
ree
l
y mo
ld
a
bl
e ceram
i
c,
P
O
WERBAL
L
®
A
second step with changed production technology
permitted production o
f
f
reely moldable tube
g
eo-
m
etr
i
es.
Thi
s ma
d
e
i
t poss
ibl
e to pro
d
uce roun
d
ce-
r
a
m
ic
a
r
c
t
ubes
w
i
t
h
a
co
n
s
t
a
nt w
all
t
hick
n
ess
– t
he
P
O
WERBALL
®
a
r
c
t
ubes
. Th
e
r
ou
n
d
fo
rm
a
n
d
co
n
s
t
a
nt
wa
ll
t
hi
c
k
ness
b
roug
h
t cons
id
era
bl
e a
d
vantages.
Th
e
possibility o
f
f
urther increasin
g
the wall temperature
improves luminous e
ff
icacy and colour renderin
g
. The
absence o
f
the thick plu
g
at the end o
f
the tube re-
d
uces
ligh
t a
b
sorpt
i
on
i
n t
hi
s area, resu
l
t
i
n
g
i
n a
high
er
l
u
min
ous
f
l
u
x with m
o
r
e
u
ni
fo
rm irr
ad
i
a
ti
o
n
c
h
a
r
ac
t
e
r-
istics. There are
f
ewer di
ff
erences in the wall tem
p
era
-
ture
b
etween t
h
e var
i
ous
b
urn
i
n
g
pos
i
t
i
ons an
d
t
h
ere
-
fo
r
e
a
l
so
s
m
a
ll
e
r
d
i
ffe
r
e
n
ces
in
co
l
ou
r
be
tw
ee
n th
e
burnin
g
positions. The reduced ceramic mass o
f
the
round tube enables the tube to heat up
f
aster, reachin
g
the photometric values more quickl
y
. Similarl
y
, when
the lamp
g
oes o
ff
, warm re-i
g
nition is possible more
qu
i
c
kl
y
b
ecause t
h
e requ
i
re
d
coo
l
er start
i
n
g
tempera-
ture
f
or normal i
g
nition devices is achieved
f
aster
.
T
he uni
f
orm wall thickness and round sha
p
e
p
roduce a
m
ore even temperature curve a
l
on
g
t
h
e
i
nner tu
b
e wa
ll
as s
h
own
i
n
Fig
. 3,
b
ase
d
on t
h
e temperature s
h
own
i
n
co
l
ours
di
a
g
ram.
Th
e steeper temperature
g
ra
di
ent
i
n
the c
y
lindrical ceramic
f
avors chemical transport pro-
cesses. Durin
g
this process, aluminum oxide ceramic
di
sso
l
ves
i
n t
h
e
liq
u
id
meta
l
h
a
lid
e me
l
t an
d
sett
l
es
at cooler
p
oints o
f
the arc tube. I
f
erosion
f
rom the
wall
g
oes too
f
ar, this can lead to leaka
g
e in the tube,
causin
g
the lamp to
f
ail. Failures due to so-called
“ceramic corrosion” are thus less likel
y
to occur in
l
am
p
s w
i
t
h
roun
d
ceram
i
c tu
b
es
.
2.2 Ceramic discharge tube
(
P
C
A =
p
p
o
ly
c
r
y
sta
lli
ne
a
l
umina
)
Th
e
use
of
a
r
c
t
ubes
m
ade
of
ce
r
a
mi
c
m
a
t
e
ri
a
l
fu
rth
er
enhanced some of the metal halide lam
p
’s
p
ro
p
erties
.
C
eramic can withstand hi
g
her temperatures than
quartz
gl
ass.
Thi
s perm
i
ts
high
er wa
ll
temperatures
thereby evaporatin
g
more o
f
the metal halide salts into
the
g
as arc and allowin
g
for more efficient use of the
chemicals.
C
eramic lam
p
s offer im
p
roved luminous
e
ff
icacy and colour renderin
g
as a result
.
Daylight
Neutral White
Neutral White de luxe
Warm White de luxe
Variation possibilities of the Colour Temperature
Multiple lines
Multiple lines
GREEN
GREEN
YELLOW
YELLOW
RED
RED
BLUE
BLUE
Tn CRI
2.1 Quartz dischar
g
e tub
e
Th
e
di
sc
h
ar
g
e tu
b
es
i
n 1st-
g
enerat
i
on meta
l
h
a
lid
e
lamps are made o
f
hi
g
h purity quartz
g
lass. This quartz
material allows
f
or stable operation at hi
g
h tempera
-
tures, is resistant to sudden changes in temperature
and is trans
p
arent. The well
p
roven H
Q
I lam
p
s are
p
ro
-
duced in various di
ff
erent
f
orms usin
g
this technolo
g
y.
H ... Hydrar
g
yrum
(G
reek-Latin for mercury
)
Q
...
Q
uart
z
I ... I
od
i
de
•
W
e
ll
proven
l
amp tec
h
no
l
o
gy
•
Wid
e watta
g
e ran
g
e 7
0
W
–
2000
W
•
C
olour tem
p
eratures u
p
to 7250
K
•
G
ood o
p
tical
p
ro
p
erties thanks to trans
p
arent
di
sc
h
ar
g
e tu
be
Fi
g
. 2a:
G
eneration of the desired
S
pectral Distribution
C
omponents in order to achieve hi
g
h luminous Effica
-
cies and
g
ood
C
olour Renderin
g