DeltaOHM HD2402, Operating Manual

Page: 35 / 58

HD2402
- 35 -
V1.4
o
L
R
(real) [W/(m² sr)] is the real radiance calculated starting from the entered
geometric parameters.
o
t_lim [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
]):
if Alpha > 100mrad it is assumed that C
α
= 100
if L
R_real
≤ 2.8
•
10
5
⇒ t > 10s (g limit satisfied)
if 2.8
•
10
5
≤ L
R_real
≤ 8.89
•
10
6
⇒ t_lim = (5
•
10
5
/L
R_real
)
4
[s] (h limit satisfied)
if 8.89
•
10
6
≤ L
R_real
⇒ t_lim < 10 μ s (i limit)
if 1.7mrad < Alpha < 100mrad it is assumed that C
α
= Alpha
if L
R_real
≤ 2.8
•
10
7
/Alpha ⇒ t > 10s (g limit satisfied)
if 2.8
•
10
7
/Alpha ≤ L
R_real
≤ 8.89
•
10
8
/Alpha ⇒ t_lim = (5
•
10
7
/(L
R_real
•
Alpha))
4
[s]
(h limit satisfied)
if 8.89
•
10
8
/Alpha ≤ L
R_real
⇒ t_lim < 10 μ s (i limit)
if Alpha < 1.7mrad it is assumed that C
α
= 1.7
if L
R_1.7
≤ 1.65
•
10
7
⇒ t > 10s (g limit satisfied)
if 1.65
•
10
7
≤ L
R_1.7
≤ 5.23
•
10
8
⇒ t_lim = (2.94
•
10
7
/(L
R_1.7
))
4
[s] (h limit
satisfied)
if 5.23
•
10
8
≤ L
R_1.7
⇒ t_lim < 10 μ s (i limit)
• Omega [sr] , the solid angle under which the source is seen by the instrument in
steradians is supplied by the user.
o
Alpha [rad] angle subtended by the source calculated starting from Omega solid
angle assuming that the source shape is circular:
Alpha = 2(Cos
-1
(1-Omega/2 π ))
o
Omega [sr] solid angle subtended by the source.
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.
o
L
R
(real) [W/(m² sr)] real radiance calculated starting from the entered geomet-
ric parameters.
o
t_lim [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
]):
if Alpha > 100mrad it is assumed that C
α
= 100
if L
R_real
≤ 2.8
•
10
5
⇒ t > 10s (g limit satisfied)
if 2.8
•
10
5
≤ L
R_real
≤ 8.89
•
10
6
⇒ t_lim = (5
•
10
5
/L
R_100
)
4
[s] (h limit satisfied)
if 8.89
•
10
6
≤ L
r_real
⇒ t_lim < 10 μ s (i limit)