DeltaOHM HD2402, Руководство по эксплуатации

Страница: 34 / 58

HD2402
- 34 -
V1.4
• Alpha angle in radiants, equal to the previous but expressed in radiants.
• Omega solid angle in steradians, it is the solid angle under which the analyzed
source is seen. This angle is used for the calculation of luminance.
This parameter is estimated based on the radiance value and not on irradiance; con-
sequently, the more detailed are the entered geometric parameters, the more plenti-
ful will be the data on limit value.
All possible cases are analyzed in the following.
• Geometric data not available :
o
L
R
(100mrad) [W/(m² sr)] radiance calculated assuming that all the light comes
from a circular area whose angular dimension is 100mrad. This value is to be
compared with the three limit values.
o
t_
lim100
[s] exposure time limit, that is the time period during which a source can
be observed without damages to the visual system. This value is calculated with
the following procedure (all radiance values are expressed in [W m
-2
sr
-1
]):
it is assumed that C
α
= 100
if L
R_100
< 2.8
•
10
5
⇒ t_lim > 10s (g limit satisfied)
if 2.8
•
10
5
≤ L
R_100
≤ 8.89
•
10
6
⇒ t_lim = (5
•
10
5
/L
R_100
)
4
(h limit satisfied)
if L
R_100
< 8.89
•
10
6
⇒ t_lim < 10 μ s (i limit)
o
L
R
(1.7mrad) [W/(m² sr)] radiance calculated assuming that all light comes from
a circular area whose angular dimension is 1.7mrad. This value is to be com-
pared with the three limit values.
o
t_
lim1.7
[s] exposure limit time, that is the time period during which a source can
be observed without damages to the visual system. This value is calculated with
the following procedure (all radiance values are expressed in [W m
-2
sr
-1
]):
it is assumed that C
α
= 1.7
if L
R_1.7
≤ 1.65
•
10
7
⇒ t_lim > 10s (g limit satisfied)
if 1.65
•
10
7
≤ L
R_1.7
≤ 5.2
•
10
8
⇒ t_lim = (2.94
•
10
7
/L
R_1.7
)
4
(h limit satisfied)
if L
R_1.7
> 5.2
•
10
8
⇒ t_lim < 10 μ s (i limit)
• Alpha [rad] , the user supplies the angular dimension of the source in radiants.
o
Alpha [rad] angle subtended by the source.
o
Omega [sr] solid angle subtended by the source, calculated starting from Alpha
angle, assuming that the source shape is circular:
Omega = 2 π (1-cos(Alpha/2))
o
L
R
(100mrad) [W/(m² sr)] radiance calculated assuming that the source angular
dimension is 100mrad.
o
L
R
(1.7mrad) [W/(m² sr)] radiance calculated assuming that the source angular
dimension is 1.7mrad.