OSRAM PrevaLED Core Z2 - Manual (Page 11)

11
OPTICAL CONSIDERATIONS
The luminous fl ux of each LED module depends on its
temperature. Therefore, 100 % of the luminous fl ux are
also achieved with the PrevaLED
® Core Z2, i.e. until the
reference temperature (t
r
) is reached. When the reference
temperature is exceeded and up to maximum temperature
(T
c
), the luminous fl ux is reduced to 95 %. If the maximum
temperature is exceeded, a further luminous fl ux reduction
comes into effect until the PrevaLED
® Core Z2 module is
fi nally switched off.
2.2. Luminous fl ux and color stability
Depending on the type of the LED module, the nominal
CCT is 2700 K, 3000 K, 3500 or 4000 K, respectively.
Depending on the variant, PrevaLED
® Core Z2 modules
provide a module-to-module color variation of less than 3
threshold value units (MacAdams steps) on the Planckian
locus around this color target. These threshold value units
can be shown within the ANSI (American National Stan-
dards Institute) norm in the following way:
Measuring tolerance for color coordinates: ±0.01
2.3. Zhaga – optical interface
In order to achieve the interchangeability of refl ectors for
spot applications, Zhaga defi nes categories for the diame-
ters of the light-emitting surfaces. PrevaLED
® Core Z2
modules are available in the categories LES 9, LES 19 and
LES 23. With LED modules of the same category, optical
systems basically achieve the same beam angles and lu-
minous intensities. With their homogeneity parameter U of
more than 90 % (i.e. with their very homogeneous radiation
without any additional light diffusion), the PrevaLED
® Core
Z2 modules facilitate all further optical light shaping by
means of refl ectors or lenses. Around the light-emitting
surface, a ringshaped surface (optical contact area, OCA)
with a defi ned height is specifi ed where refl ector optics
can be attached. In addition to the surface described in
the Zhaga specifi cation, the OCA of PrevaLED
® Core Z2
modules is positioned closer to the light-emitting surface,
so that refl ectors with smaller openings can also be used.
All PrevaLED
® Core Z2 light engines fulfi ll the Zhaga-
specifi ed requirements in terms of luminous fl ux, chroma-
ticity coordinates and beam characteristics and partially
even exceed these requirements.
LES: Light-emitting surface
OCA (Optical contact area):
Attachment and reference
surface for optics
(e.g. refl ectors, lenses)
All fi gures in mm