Osram HQI-E 150 W/NDL CL Technical Information download pdf (Page 49)

49

L

arger

d

ev

i

at

i

ons are assoc

i

ate

d

w

i

t

h

a c

l

ear t

i

nt.

Th

e

di

stance to

Pl

anc

k

i

s a

l

so

k

nown as t

h

e c

h

romat

i

c

i

t

y

g

ap

Δ

c.

C

olour renderin

g

is specified by irradiatin

g

defined test

colours in succession with a reference source

(

an ideal

Planck radiator with the tem

p

erature and there

f

ore co

-

lour temperature of the test li

g

ht source

)

and with the

test li

g

ht source. The speci

f

ic resultant colour shi

f

t

Δ

E

i

is de

f

ined

f

or ever

y

test colour i in the uni

f

orm colou

r

s

p

ace

C

IE 1964

(

W*, U*, V*

).

The speci

f

ic colour renderin

g

index

R

i

is de

f

ined as

fo

ll

o

w

s

R

i

= 1

00

– 4.

6

Δ

e

i

Every special colour renderin

g

index can there

f

ore

r

eac

h

a

m

a

xim

u

m v

a

l

ue

of

1

00

wh

e

n th

e

t

es

t

co

l

our

appears identical under re

f

erence and test li

g

ht

source.

N

e

g

at

i

ve va

l

ues are a

l

so poss

ibl

e w

i

t

h

g

reater

deviations

(

and hence lar

g

er

Δ

E

i

).

8

.

2

.1

Tes

t

colou

r

s

f

r

o

m

s

t

a

n

da

r

d

DIN

6

1

69

Th

e

a

rithm

e

ti

c

m

ea

n

f

r

o

m th

e

f

ir

s

t

8

t

es

t

co

l

ou

r

s

(see Table 4) shows the

g

eneral colour renderin

g

index

C

RI or

R

a

.

Th

e

g

enera

l

co

l

our ren

d

er

i

n

g

i

n

d

ex resu

l

ts

i

n t

h

e

colour renderin

g

levels

f

or li

g

ht sources

g

iven in

T

ab

l

e

5.

Table 5:

C

olour rendering level

s

A

part

f

rom the

f

irst 8 colour renderin

g

indexes,

DIN 6169 also de

f

ines other test colours

,

which are

fou

r

sa

t

u

r

a

t

ed

co

l

ou

r

s

a

n

d

add

iti

o

n

a

l t

es

t

co

l

ou

r

s

. Th

e

f

urther test colours

p

ermit a more

p

recise descri

p

tion

o

f

the colour renderin

g

properties o

f

the li

g

ht source.

In principle it is possible to de

f

ine an

y

random number

o

f

man

y

di

ff

erent test colours

.

Th

an

k

s to a

high

er poss

ibl

e wa

ll

l

oa

d

, t

h

e co

l

our ren

-

derin

g

properties when usin

g

P

O

WERBALL

®

tec

h

no

l

o

g

y

h

ave been visibl

y

improved compared to the lamp with

cy

lindrical ceramic arc tube. A

f

urther improvement

specific Color rendering index

HQI-T POWERSTAR

Typical lamp with

cylindrical ceramic

Fi

g

. 52:

C

omparison of the specific colour renderin

g

indices for various metal halide lamps

S

aturated colours and additional test colou

r

s

Te

s

t

colour

s

R1 – Dusky pink

R3 – Yellow green

R5 – Turquoise blue

R7 – Aster violet

R2 – Mustard yellow

R4 – Light green

R6 – Sky blue

R8 – Syringa violet

R9 – Red

R11 – Green

R13 – Skin colour

R10 – Yellow

R12 – Blue

R14 – Leaf green

Table

4:

Tes

t

colou

r

s

f

r

o

m

DIN

6

1

69

E

v

alua

t

ion

C

olour renderin

g

level

C

olour renderin

g

index

C

RI

V

ery

g

oo

d

1

A

≥

90

V

ery goo

d

1

B

80

–

89

G

o

o

d2

A7

0

– 7

9

G

o

o

d2

B6

0

–

69

S

ubo

p

tima

l

34

0

–

59

Suboptima

l

42

0

–

39

1 2 ... 44 45 46 47 48 49 50 51 52 53 54 55 56

Comments to this Manuals

No comments