U.S. patent application number 14/128495 was filed with the patent office on 2014-07-17 for angle-selective irradiation insulation on a building envelope.
This patent application is currently assigned to SOLAR CAMPUS GMBH. The applicant listed for this patent is Stephan A. Mathez, Walter Sachs. Invention is credited to Stephan A. Mathez, Walter Sachs.
Application Number | 20140196395 14/128495 |
Document ID | / |
Family ID | 46321012 |
Filed Date | 2014-07-17 |
United States Patent
Application |
20140196395 |
Kind Code |
A1 |
Mathez; Stephan A. ; et
al. |
July 17, 2014 |
ANGLE-SELECTIVE IRRADIATION INSULATION ON A BUILDING ENVELOPE
Abstract
In a method for producing a building envelope part (19) for
angle-selective irradiation insulation on a building envelope,
which building envelope part (19) has an outer surface (29), an
inner surface (39) opposite the outer surface (29), and a side edge
that bounds the outer surface (29) and the inner surface (39), the
outer surface (29) is provided with outer structures (219) and the
inner surface (39) is provided with inner structures (319). The
outer structures (219) and the inner structures (319) are arranged
relative to each other in such a way that the building envelope
part (19) has different transparency depending on the spatial angle
of incidence. The outer structures (219) and the inner structures
(319) are arranged in particular with regard to an orientation of
an intended application of the building envelope part (19) and with
regard to the latitude of the intended application of the building
envelope part (19). By means of the design of the outer structures
and the inner structures according to the invention, it is possible
that the outer structures and the inner structures are arranged in
such a way that a building envelope comprising the building
envelope part is optimally adapted to an orientation and in
particular to an orientation deviating from southern orientation,
to tilted or horizontal arrangements, or to an arbitrary latitude.
Thus the transmittance behavior of the building envelope part can
be accordingly optimized for the particular situation.
Inventors: |
Mathez; Stephan A.;
(Wetzikon, CH) ; Sachs; Walter; (Zurich,
CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mathez; Stephan A.
Sachs; Walter |
Wetzikon
Zurich |
|
CH
CH |
|
|
Assignee: |
SOLAR CAMPUS GMBH
Wetzikon
CH
|
Family ID: |
46321012 |
Appl. No.: |
14/128495 |
Filed: |
June 20, 2012 |
PCT Filed: |
June 20, 2012 |
PCT NO: |
PCT/EP2012/061835 |
371 Date: |
March 21, 2014 |
Current U.S.
Class: |
52/406.1 |
Current CPC
Class: |
F24S 50/80 20180501;
E06B 3/6722 20130101; E04B 1/62 20130101 |
Class at
Publication: |
52/406.1 |
International
Class: |
E04B 1/62 20060101
E04B001/62 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 21, 2011 |
EP |
11170686.7 |
Claims
1. A building envelope part (1; 17; 18; 19) for angle-selective
irradiation insulation, wherein the building envelope part (1; 17;
18; 19) comprises an outer surface (2; 27; 28; 29) with outer
structures (21; 217; 218; 219), an inner surface (3; 37; 38; 39)
opposite the outer surface (2; 27; 28; 29) with inner structures
(31; 317; 318; 319) and a side edge (5) that borders the outer
surface (2; 27; 28; 29) and inner surface (3; 37; 38; 39), wherein
the outer structures (21; 217; 218; 219) and inner structures (31;
317; 318; 319) are arranged relative to each other in such a way
that the translucency of the building envelope part (1; 17; 18; 19)
varies as a function of the spatial angle of incidence,
characterized in that the outer structures (21; 217; 218; 219) and
inner structures (31; 317; 318; 319) are arranged at an acute angle
to the side edge (5).
2. The building envelope part (1; 17; 18; 19) according to claim 1,
in which the outer structures (21; 217; 218; 219) are arranged as
light diffusers, and the inner structures (31; 317; 318; 319) are
arranged as optically opaque.
3. The building envelope part (1; 17; 18; 19) according to claim 1,
in which the outer structures (21; 217; 218; 219) are prismatic,
and the inner structures (31; 317; 318; 319) are optically opaque
in design.
4. The building envelope part (1; 17; 18; 19) according to claim 2
or 3, in which the inner structures (31; 317; 318; 319) are
designed as light reflectors.
5. The building envelope part (1; 17; 18; 19) according to claim 2
or 3, in which the inner structures (31; 317; 318; 319) are
arranged as light absorbers, wherein the light absorbers are
photovoltaic light absorbers.
6. The building envelope part (1; 17; 18; 19) according to claim 1,
in which the outer structures (21; 217; 218; 219) comprise parallel
stripes arranged in a common plane, and the inner structures (31;
317; 318; 319) comprise parallel stripes arranged in a common
plane.
7. The building envelope part (1; 17; 18; 19) according to claim 6,
in which the outer structures (21; 217; 218; 219) are arranged
parallel to the inner structures (31; 317; 318; 319), wherein the
common plane of the outer structures (21; 217; 218; 219) and the
common plane of the inner structures (31; 317; 318; 319) are
different.
8. The building envelope part (1; 17; 18; 19) according to claim 1,
in which the outer structures (21; 217; 218; 219) are arranged in a
direction perpendicular to the outer surface (2; 27; 28; 29) and to
the inner surface (3; 37; 38; 39), offset in relation to the inner
structures (31; 317; 318; 319).
9. The building envelope part (1; 17; 18; 19) according to claim 1,
in which the outer structures (21; 217; 218; 219) and inner
structures (31; 317; 318; 319) are essentially lamellar in
design.
10. A method for manufacturing a building envelope part (1; 17; 18;
19) for angle-selective irradiation insulation, wherein the
building envelope part (1; 17; 18; 19) comprises an outer surface,
an inner surface (3; 37; 38; 39) opposite the outer surface (2; 27;
28; 29), and a side edge (5) that borders the outer surface (2; 27;
28; 29) and inner surface (3; 37; 38; 39), in which the outer
surface (2; 27; 28; 29) is provided with outer structures (21; 217;
218; 219) and the inner surface (3; 37; 38; 39) is provided with
inner structures (31; 317; 318; 319), wherein the outer structures
(21; 217; 218; 219) and inner structures (31; 317; 318; 319) are
arranged relative to each other in such a way that the translucency
of the building envelope part (1; 17; 18; 19) varies as a function
of the spatial angle of incidence, characterized in that the outer
structures (21; 217; 218; 219) and inner structures (31; 317; 318;
319) are arranged taking into account the orientation of a provided
application of the building envelope part (1; 17; 18; 19) and
taking into account the latitude of the provided application of the
building envelope part (1; 17; 18; 19).
11. The method according to claim 10, in which the longitudinal
axes of the outer structures (21; 217; 218; 219) and inner
structures (31; 317; 318; 319) are aligned parallel to an
intersecting line between the plane of the solar ecliptic and the
plane of the building envelope part (1; 17; 18; 19) in the provided
application if the building envelope part (1; 17; 18; 19) can be
reached by direct solar radiation on all days of a calendar year in
the provided application.
12. The method according to claim 11, in which the acute angle
between the outer structures (21; 217; 218; 219) and side edge (5)
or between the inner structures (31; 317; 318; 319) and side edge
(5) is established by a mathematical expression that correlates the
variables .omega., .beta., .gamma. and .phi., preferably according
to the equation .omega. = - sgn ( .phi. * sin ( .gamma. ) ) *
arccos ( sin ( .phi. ) * sin ( .beta. ) + cos ( .phi. ) * cos (
.beta. ) * cos ( .gamma. ) cos ( .phi. ) * cos ( .beta. ) + sin (
.phi. ) * cos ( .gamma. ) * sin ( .beta. ) ) 2 + sin 2 ( .gamma. )
* sin 2 ( .beta. ) ) ##EQU00008## wherein .omega. is the acute
angle, .beta. is an inclination, and .gamma. is an alignment of the
building envelope part (1; 17; 18; 19) in the provided application,
and .phi. is the latitude in the provided application.
13. The method according to claim 10, in which a first projected
angle of incidence with a maximum light transmittance through the
building envelope part (1; 17; 18; 19) is established.
14. The method according to claim 10, in which a second projected
angle of incidence with a minimum light transmittance through the
building envelope part (1; 17; 18; 19) is established.
15. The method according to claim 13, in which the building
envelope part (1; 17; 18; 19) is configured in such a way that the
outer structures (21; 217; 218; 219) comprises parallel stripes
arranged in a common plane, and the inner structures (31; 317; 318;
319) comprises parallel stripes arranged in a common plane.
16. The method according to claim 15, in which the building
envelope part (1; 17; 18; 19) is configured in such a way that the
outer structures (21; 217; 218; 219) are arranged parallel to the
inner structures (31; 317; 318; 319), wherein the common plane of
the outer structures (21; 217; 218; 219) and the common plane of
the inner structures (31; 317; 318; 319) are different, and that
the stripes of the outer structures (21; 217; 218; 219) and stripes
of the inner structures (31; 317; 318; 319) are established by a
mathematical expression that correlates the variables r, d,
.alpha..sub..+-. and n, preferably according to the equation r d =
sin ( .alpha. + ) n 2 - sin 2 ( .alpha. + ) - sin ( .alpha. - ) n 2
- sin 2 ( .alpha. - ) , ##EQU00009## wherein r is the width of one
of the stripes of the inner structures (31; 317; 318; 319), d is
the thickness of the building envelope part (1; 17; 18; 19), n is
the average refraction index of the building envelope part (1; 17;
18; 19), .alpha..sub.+ is the first projected angle of incidence,
and .alpha..sub.- is the second projected angle of incidence.
17. The method according to claim 15, in which the building
envelope part (1; 17; 18; 19) is configured in such a way that a
width of the stripes of the exterior side, a width of the stripes
of the interior side, and a respective distance between the stripes
are essentially identically dimensioned.
18. A computer program comprising a program code structure
configured to implement the method according to claim 10 when being
executed on a computer.
19. A computer program comprising a program code structure
configured to implement the method according to claim 11.
20. A computer program comprising a program code structure
configured to implement the method according to claim 12.
Description
BENEFIT CLAIM
[0001] The present application claims the benefit under 35 U.S.C.
119 of priority from international application PCT/EP2012/061835
filed 20 Jun. 2012, which claims priority to European application
EP11170686.7 filed 21 Jun. 2011, the entire contents of which are
hereby incorporated by reference for all purposes as if fully set
forth herein.
TECHNICAL FIELD
[0002] The invention relates to a building envelope part according
to the preamble of independent claim 1, as well as to a method for
manufacturing such a building envelope and a computer program for
implementing such a method.
[0003] Such building envelope parts exhibit an outer surface with
outer structures, an inner surface opposite the outer surface with
inner structures, and a side edge that bounds the outer surface and
inner surface, wherein the outer structures and inner structures
are arranged relative to each other in such a way that the building
envelope part has a varying translucency depending on the spatial
angle of incidence, for example to solar radiation, and can be used
in building technology for angle-selective irradiation insulation
on a building envelope.
PRIOR ART
[0004] In order to specifically vary the absorbance of a building
relative to solar radiation, use is today made of building
envelopes or facades with an angle-selective transmittance
behaviour. In particular, an irradiation insulation that allows
more or less transmittance to arise over the seasonal variation of
the sun's trajectory can be achieved in this way. For example, this
type of building envelope makes it possible to achieve a high
transmittance of direct solar radiation in winter, thereby lending
support to the heating process, and a low transmittance in the
summer to protect against overheating, so that cooling can be
reduced. Angle-selective building envelopes or facades along with
transparent thermal insulation are optimized in terms of their
seasonal transmittance behaviour for central northern latitudes on
south fronts the building or on south facades. For example,
European Standard (EN) 13363 "Solar Protection Devices in
Combination with Glazing--Calculation of Solar Radiation and Degree
of Light Transmittance", which was adopted by the German Institute
for Standardization (DIN), discusses spatial angles with elevations
of 0.degree. to 90.degree. and azimuth angles of -90.degree. to
+90.degree. for corresponding window blinds or shading elements. In
this context, the term "elevation" relates to a vertical angle over
a horizontal plane. The term "azimuth" in this sense relates to the
deviation from south, wherein an azimuth angle of -90.degree.
denotes an east orientation, -45.degree. a southeast orientation,
0.degree. a south orientation, +45.degree. an southwest
orientation, and +90.degree. a west orientation. Such
angle-selective building envelopes often exhibit lamellar,
horizontally arranged structures. The building envelopes are here
angle-selective in that the transmittance or degree of
transmittance for a south orientation and varying elevations--this
direction is referred to as the transversal axis--can change
significantly as a function of the angle.
[0005] In this conjunction, building envelope parts are among other
things fabricated as components for building envelopes that, once
built in, permit an angle-selective irradiation insulation for the
building envelope. For example, WO 01/53756 A2 describes a glass
pane as a component with an outer surface and inner surface, which
has prismatic elevations as structures on the outer surface or
inner surface. The prismatic elevations are intended to divert
light so as to outwardly redirect steeply incident sunlight in the
summer, while allowing shallowly incident sunlight to freely pass
through the glass pane to the inside in the winter.
[0006] The transmittance or degree of transmittance remains
approximately constant or at most tapers off in border areas for a
light source moving from east to west given an identical
elevation--this direction is referred to as the longitudinal axis.
As a result, the known building envelopes of building envelope
parts are either unsuitable or limitedly effective for orientations
that deviate from the south, for inclined or horizontal
configurations, for example roof surfaces, as well as for other
geographic latitudes. For example, the stipulation that the solar
altitude be high in the summer and low in the winter is not
applicable. In these orientations, the strongly transmitting area
of the angular range is rather traversed during sunrise or sunset,
while the high solar altitude is encountered only in a border area
or not at all in these orientations. As a consequence, the
irradiation on the building is often very high when the building
exhibits such a known building envelope, and the amount of
irradiated energy is often significant given the longer duration of
sunshine in the mornings and evenings, and can help cause the
building to overheat.
[0007] Therefore, the object of the present invention is to propose
a building envelope part or the manufacture of a building envelope
part that enables an angle-selective irradiation insulation on the
building envelope for any orientations and inclinations of the
building envelope part, as well as for any geographic latitudes of
the building location.
DESCRIPTION OF THE INVENTION
[0008] According to the invention, the object is achieved by a
building envelope part as defined by the features in independent
claim 1, as well as by a method as defined by the features in
independent claim 10, and a computer program as defined by the
features in independent claim 18. Advantageous embodiments of the
invention may be gleaned from the features in the dependent
claims.
[0009] The gist of the invention is as follows: A building envelope
part for angle-selective irradiation insulation on a building
envelope exhibits an outer surface with outer structures, an inner
surface opposite the outer surface with inner structures, and a
side edge that borders the outer surface and inner surface, or
joins the outer surface with the inner surface. The outer
structures and inner structures are here arranged relative to each
other in such a way that the translucency of the building envelope
part varies as a function of the spatial angle of incidence. The
outer structures and inner structures are here arranged at an acute
angle to the side edge.
[0010] In connection with the invention, the term "building
envelope part" relates to parts exposed to direct or diffuse solar
radiation or artificial light, attachment or mounting elements of a
building, such as facades, facade elements, transparent thermal
insulation elements (TWD), windows, roofs and porches, to energy
generating systems, such as thermal, photovoltaic and hybrid
collectors, as well as to targeted light or visual guidance
systems. In particular, the term "building envelope part" can be
construed as any suitable, preferably plate-type construction
having a round, triangular, square or hexagonal shape, whose border
is designated as a side edge in terms of this invention, for use in
a building envelope, for example a preferably structured glass or
acrylic glass pane, a plastic plate, a metallic, mineral or wooden
construction or something similar. In particular, a low-iron glass
can be used as the building envelope part. The building envelope
part can be configured as a one-piece component or composed of
several elements. For example, it can also be designed as laminated
glass, in which in particular correspondingly printed glass panes
are used, and prefabricated films or switchable layers are applied
to panes of glass, or attached between several glass panes. In
conjunction with the invention, the term "spatial angle of
incidence" is understood as the angle doublet comprised of a zenith
angle between the perpendicular to the outer surface of the
building envelope part or the light incident on the building
envelope part, as well as of an azimuth angle between a defined
angle of the outer structure and the perpendicularly projected
light incident on the outer surface of the building envelope part.
Without any explicit other explanations, the terms "south",
"north", "north hemisphere", "June 21" and "December 21" used in
conjunction with the invention refer to locations in the northern
hemisphere. The latter are replaced by "north", "south", "south
hemisphere", "December 21" and "June 21" respectively for locations
in the southern hemisphere in these cases.
[0011] The outer structures and inner structures can extend from
one side edge to a possible other side edge on the outer surface or
on the inner surface. In particular, they can also each exhibit an
oblong expansion, wherein this oblong expansion can define an axis
of the outer structures. The areas of the exterior side between the
outer structures and the areas of the interior side between the
inner structures can remain unchanged or unmachined and
translucent. The outer structures and/or inner structures can be
covered by a protective layer as a safeguard against damaging
influences, for example in the case of a laminated glass. The acute
angle between the outer structures or inner structures according to
the invention relates to the plane of the outer surface or inner
surface, so that it becomes particularly evident from a top view of
the outer surface or inner surface. In particular, it can encompass
all angles that are smaller than 90.degree., and especially
significantly smaller than 90.degree., i.e., for example smaller
than 85.degree., smaller than 80.degree., smaller than 70.degree.,
smaller than 60.degree., smaller than 50.degree., smaller than
40.degree., smaller than 30.degree., smaller than 20.degree.,
smaller than 10.degree. or smaller than 5.degree.. Concurrently
with acute-angled arrangement of the outer structures or inner
structures and the side edge, the outer structures and inner
structures can also be arranged at an obtuse angle relative to the
side edge. For example, the sum of this obtuse angle and the acute
angle yields 180.degree. at the tangent of the side edge.
[0012] The acute-angled arrangement according to the invention of
the outer structures or an axis thereof and the inner structures or
an axis thereof relative to the side edge makes it possible to
arrange the outer structures and inner structures in such a way as
to optimally adjust a building envelope encompassing the building
envelope part to an orientation deviating from the south, to an
inclined or horizontal arrangement, or to any geographic latitude.
As a consequence, the transmittance behaviour of the building
envelope part can be appropriately optimized to the respective
situation. For example, the circumstances presented by a roughly
east or west orientation of the building envelope part can be taken
into account in a relatively effective way. A transmittance of
about 60% can take place with respect to angles of incidence
typically encountered in winter, for example, while a transmittance
of about 20% can take place for those typically encountered in
summer, for example. The building envelope part typically has
strictly a passive effect, and can be adjusted not just to the
solar altitude and facade orientation, but rather also to the
length of the heating or cooling period of a building. For example,
the building envelope part can further be comparatively durable as
a glazing, and provide good weather protection for the building. In
addition, the building envelope part can be manufactured in a
comparatively cost effective manner, and visually adjusted to be
suitable for residential, commercial and industrial premises. The
rear section of the building envelope part according to the
invention can also be combined with housing panels comprised of
massive wood, other materials or structures as the thermal capacity
store and/or provided with ventilation dampers to utilize cooling
through natural convection, which can be opened or closed
seasonally or as needed.
[0013] According to the invention, then, the irradiation insulation
on the building can be controlled to conform to the situation,
wherein the outer structures or an axis thereof and the inner
structures or an axis thereof to this end run inclined at a
specific angle relative to a side edge, depending on the respective
celestial orientation of the provided application for the building
envelope part and the latitude. For example, the solar radiation
can accordingly also be used at orientations other than toward the
south for heating purposes, and at the same time offer irradiation
insulation to protect against overheating. As may be gleaned from
the aforementioned EN 13363, for example, the latter standard is
not to be used for elevations of less than 0.degree., which is
factually tantamount to saying that only horizontally lying
lamellae or structures can be considered according to the standard.
If the lamellae or structures are inclined, irradiation elevations
of less than 0.degree. are also possible, which lie outside the
evaluation range of this standard. As a consequence, it can be
inferred that the same method can also yield clearly better results
in the fight against overheating, especially in the summer, and in
the generation of energy during the winter even at latitudinal
lines other than the average and at facade orientations other than
toward the south. Since a comparatively finely resolving angular
function can be taken into account in the building envelope part
according to the invention, the focus can be placed on situations
with more than one heating and/or cooling period. In addition, the
building envelope part according to the invention can also be
configured to serve as angle-selective, situation-adapted
irradiation insulation for artificial light.
[0014] In one exemplary embodiment of the building envelope part,
the outer structures are designed as light diffusers, and the inner
structures are designed as optically opaque. In this conjunction,
the term "light diffusers" relates in particular to structures that
diffusely scatter incident light. For example, the outer structures
as light diffusers can be applied to the glass pane through
printing, etching, sandblasting, roughening, as a film or in some
other way. As a consequence, the angle-dependent transmittance can
be achieved via the diffusely scattering, e.g., printed,
sandblasted, etched or roughened outer structures and reflecting or
absorbing inner structures, and optimized for the exact
requirements. For example, optically opaque structures can be
applied to the building envelope part through printing, as a film
or in some other way, especially if the building envelope part is
designed as a glass or acrylic glass pane. Outer structures and
inner structures configured in this way make it possible to scatter
the solar radiation incident on the exterior side of the building
envelope part in a specific first spatial angle of incidence range
on the outer structures in such a way that at least a portion
thereof is deflected on the optically opaque inner structures while
penetrating the building part. This allows additional solar
radiation other than the solar radiation directly incident on the
optically opaque inner structures in the first spatial angle of
incidence range to be incident on the optically opaque inner
structures, which can in particular elevate the radiation
insulation, for example in the summer. At the same time, the outer
structures and inner structures configured in this way can scatter
the solar radiation incident on the exterior side of the building
envelope part in a specific second spatial angle of incidence range
in such a way that at least a portion thereof is guided between and
through the optically opaque inner structures while penetrating the
building part. This allows additional solar radiation other than
the solar radiation that passes directly by the optically opaque
inner structures to penetrate through the building envelope part in
the second spatial angle of incidence range, which in particular
can diminish the irradiation insulation, for example in winter.
[0015] In another exemplary embodiment, the outer structures are
prismatic, and the inner structures optically opaque in design.
When the outer structures and inner structures are configured in
this way, the solar radiation incident on the external side of the
building envelope part in a specific first spatial angle of
incidence range can be bundled on the outer structures in such a
way that at least a portion thereof is deflected on the optically
opaque inner structures while penetrating through the building
envelope part. This allows additional solar radiation other than
the solar radiation directly incident on the optically opaque inner
structures in the first spatial angle of incidence range to be
incident on the optically opaque inner structures, which can in
particular elevate the radiation insulation, for example in the
summer. At the same time, the outer structures and inner structures
configured in this way can bundle the solar radiation incident on
the exterior side of the building envelope part in a specific
second spatial angle of incidence range in such a way that at least
a portion thereof passes the optically opaque inner structures
while penetrating the building part. This allows additional solar
radiation other than the solar radiation that passes directly
through the optically opaque inner structures to penetrate through
the building envelope part in the second spatial angle of incidence
range, which in particular can diminish the irradiation insulation,
for example in winter.
[0016] In the two exemplary embodiments of outer structures and
inner structures described above, the optically opaque inner
structures can be configured as light reflectors. For example, the
inner structures can be designed as a mirror coating, such as a
printed silver layer, an opaque coloration or a geometric,
reflecting structure, in particular in glass pane-like building
envelope parts. This allows the irradiation incident on the inner
structures in particular in the first spatial angle of incidence
range to be reflected via the outer surface out of the building
envelope part. As a result, the building envelope part can be kept
deeply heated. As an alternative, the optically opaque inner
structures in the mentioned two exemplary embodiments of outer
structures and inner structures described above can be configured
as light absorbers, wherein the light absorbers are preferably
photovoltaic light absorbers. This makes it possible to prevent
radiation incident on the inner structure from penetrating through
the building envelope part on the one hand, while the energy of the
irradiation to be insulated can be used for photovoltaic power
production on the other, in particular in the summer. Light
bundling allows this to happen with a high efficiency.
[0017] In another exemplary embodiment, the outer structures are
designed to be light polarizing in a first way, and the inner
structures are designed to be light polarizing in a second way
complementary to the first way. This type of configuration for the
outer structures and inner structures makes it possible to
completely cancel out direct radiation at certain angles of
irradiation. Given the other extreme, i.e., at certain other angles
of irradiation, a transmittance of about 50% relative to
non-polarizing inner and outer structures can be achieved, for
example. Comparatively high contrast ratios can be achieved as a
result.
[0018] In particular the outer structures can also be designed as a
three-dimensional structure, for example an inclined flank, as a
result of which both the degree of transmittance and reflection can
be elevated depending on the angle of irradiation. The outer
structures and inner structures can also be contiguous in design,
for example have an L-shaped cross section. The outer surface
and/or inner surface can be provided with anti-reflective coatings,
making it possible to increase the degree of transmittance. The
outer surface and/or inner surface can be provided with
wavelength-selective infrared reflectors, as a result of which the
heat dissipation of the underlying building envelope layer can be
reduced without significantly diminishing the degree of
transmittance for visible light.
[0019] The outer structures preferably encompass parallel stripes
arranged in a common plane, and the inner structures encompass
parallel stripes arranged in a common plane. The stripes of the
outer structures and the stripes of the inner structures can here
each exhibit straight sides and a fixed width. This type of
configuration for the outer structures and inner structures enables
a comparatively simple, expedient construction of the building
envelope part. The outer structures are here preferably arranged
parallel to the inner structures, wherein the common plane of the
outer structures and the common plane of the inner structures are
different. The stripes of the outer structures and the stripes of
the inner structures are here established by mathematical
expressions that correlate the variables r, d, m, c,
.alpha..sub..+-. and n, and are preferably formulated according to
the equations
r d = sin ( .alpha. + ) n 2 - sin 2 ( .alpha. + ) - sin ( .alpha. -
) n 2 - sin 2 ( .alpha. - ) ##EQU00001##
and m=c=r, wherein m is the width of one of the stripes of the
outer structures, for example in [mm], r is the width of one of the
stripes of the inner structures, for example in [mm], c is the
distance between the stripes of the outer structures, for example
in [mm], d is the thickness of the building envelope part, for
example in [mm], n is the average refraction index of the building
envelope part, .alpha..sub.- is the projected angle of incidence
for light to be insulated, and .alpha..sub.+ is the projected angle
of incidence for light not to be insulated. This type of
configuration for the outer structures and inner structures enables
a comparatively efficient, readily calculable construction of the
building envelope part.
[0020] The outer structures are preferably arranged in a direction
perpendicular to the outer surface and inner surface, offset in
relation to the inner structures. Because the outer structures and
inner structures thus do not lie on top of each other,
angle-selective irradiation insulation can be efficiently achieved
by the building envelope part. The angular ranges in which the
irradiation is to be insulated or not insulated can be
comparatively easily adjusted by suitably selecting the offset for
the outer structures in relation to the inner structures in the
direction perpendicular to the outer surface and inner surface.
[0021] The acute angle preferably ranges between about 25.degree.
and about 55.degree., or about -55.degree. and about -25.degree..
With such an acute angle, an optimized building envelope part can
be fabricated in particular for European latitudinal lines, and
especially for building envelope parts oriented toward the east or
west. Smaller angles are best used for building envelope parts more
strongly oriented toward the south, while larger angles are best
used for building envelope parts more strongly oriented toward the
north.
[0022] The building envelope part preferably exhibits an
essentially rectangular shape with four side edges. This type of
basic shape for the building envelope part enables a comparatively
simple manufacture, as well as a comparatively simple, efficient
integration into a building envelope. The side edge arranged at an
acute angle in relation to the outer structures or an axis thereof
and the inner structures or an axis thereof is here preferably
essentially horizontally aligned in a provided application for the
building envelope part.
[0023] The outer structures and inner structures are preferably
essentially lamellar in design. For example, the term "lamellar"
can be understood as a parallel arrangement of stripes in a plane,
wherein these stripes exhibit straight sides and a certain width.
This type of lamellar configuration for the outer structures and
inner structures enables a comparatively simple, efficient
construction and manufacture of the building envelope part.
[0024] The building envelope part according to the invention
described above can also be used for artistically designing the
building envelope or for other visual purposes by adjusting the
outer structures and inner structures so that a desired graphic
pattern of whatever geometry desired can be achieved, e.g., via
discontinuous stripes or dot-like patterns, or by using colour
adjusted building envelope parts. While this allows for numerous
possibilities in relation to the artistic design of the facades, it
can also easily have a negative influence on the contrast ratio for
the structures. Striped structures in a transverse direction can
also generate a Moire Effect. When passing in front of a facade
equipped with such a building envelope part, these Moire stripes
can wander along, so that corresponding effects can be used in
targeted fashion. Likewise, the building envelope part can give
rise to wavelength-dependent effects at the boundaries of light
diffusing to right on the outer surface owing to the colour
dispersion of direct radiation during reflection on the inner
surface of the glass, as a result of which the blues or reds of the
spectrum can be reflected or filtered out. This can slightly alter
the hue of the reflected and transmitted light, and targeted use
can be made of the corresponding effects. In addition, the direct
portion of reflection can essentially be eliminated by suitably
selecting the shape and position of the outer structures and inner
structures. This can be of interest with respect to the appearance
of the building, or so as to avoid disturbing reflection effects.
In addition, for example, building envelope parts designed as glass
panes can offer an infinitely variable screen, and the essentially
dull effect produced by the glass surface itself can prevent
accidents that involve flying birds, even given a comparatively low
dullness portion. For example, the building envelope part can be
mounted as facade glass in front of windows, opaque walls and
insulations or in front of transparent insulation (TWD). Any air
space between the glass and facade lying behind it can be naturally
or artificially ventilated, or used for generating energy. For
diffuse, i.e., non-direct solar radiation, the building envelope
part can exhibit an elevated transmittance for diffuse light, for
example, which can be advantageous in the summer during bad
weather, which creates a demand for heating energy.
[0025] Another aspect of the invention relates to a method for
manufacturing a building envelope part for angle-selective
irradiation insulation on a building envelope, such as a building
envelope part of the kind described above, wherein the building
envelope part exhibits an outer surface, an inner surface opposite
the outer surface, and a side edge that borders the outer surface
and inner surface or joins the outer surface with the inner
surface. The outer surface is provided with outer structures, and
the inner surface is provided with inner structures, wherein the
outer structures and inner structures are arranged in relation to
each other in such a way that the building envelope part varies in
translucence depending on the spatial angle of incidence. The
arrangement of the outer structures and inner structures includes
the orientation of a provided application for the building envelope
part and the latitude of the provided application for the building
envelope part. In this conjunction, the term "provided orientation"
relates to the alignment and inclination in which the building
envelope part is to be incorporated, for example in which it is to
be built into a building envelope. In this conjunction, the term
"provided latitude" relates in particular to the location of the
place at which the building envelope part is to be used or
applied.
[0026] The method according to the invention allows the
individualized manufacture of a building envelope part, so that the
highest possible efficiency in application can be achieved. In
particular, the method according to the invention also makes it
possible to efficiently implement the advantages described above in
conjunction with the building envelope part according to the
invention.
[0027] The longitudinal axes of the outer structures and inner
structures are preferably aligned parallel to an intersecting line
between the plane of the solar ecliptic and the plane of the
building envelope part in the provided application if the building
envelope part can be reached by direct solar radiation on all days
of a calendar year in the provided application. This enables a
comparatively efficient usage for this type of application for the
building envelope part. The acute angle between the outer
structures and side edge or between the inner structures and side
edge is here established for building envelope parts inclined
however desired by a mathematical expression that correlates the
variables .omega., .beta., .gamma. and .phi., preferably according
to the equation
.omega. = - sgn ( .phi. * sin ( .gamma. ) ) * arccos ( sin ( .phi.
) * sin ( .beta. ) + cos ( .phi. ) * cos ( .beta. ) * cos ( .gamma.
) cos ( .phi. ) * cos ( .beta. ) + sin ( .phi. ) * cos ( .gamma. )
* sin ( .beta. ) ) 2 + sin 2 ( .gamma. ) * sin 2 ( .beta. ) )
##EQU00002##
and for vertically inclined building envelope parts by a
mathematical expression that correlates the variables .omega.,
.gamma. and .phi., preferably according to the equation
.omega. = - sgn ( .phi. * sin ( .gamma. ) ) * arccos ( sin ( .phi.
) 1 - cos 2 ( .phi. ) * cos 2 ( .gamma. ) ) , ##EQU00003##
wherein .omega. is the acute angle, .beta. is an inclination
(vertical: .beta.=90.degree.) and .gamma. is an alignment (south:
.gamma.=0.degree., west: .gamma. positive) of the building envelope
part and .phi. is the latitude (equator: .phi.=0.degree., north
hemisphere: .phi. positive) in the provided application. Such a
calculation method can be used to precisely dimension the building
envelope part for the further type of application in a
comparatively simple manner.
[0028] The longitudinal axes of the outer structures and inner
structures are preferably aligned perpendicular to an intersecting
line between the plane of the solar ecliptic and the plane of the
building envelope part in the provided application if the building
envelope part cannot be reached by direct solar radiation on all
days of a calendar year in the provided application. For example,
this condition can be satisfied on the northern hemisphere if the
building envelope part is aligned toward the north. This also
enables a comparatively efficient usage for this additional type of
application for the building envelope part by having the degree of
transmittance for the projected angle of incidence be as small as
possible during sunrise and/or sunset, and otherwise as large as
possible to utilize the diffuse sunlight in winter.
[0029] A first projected angle of incidence with a maximum light
transmittance through the building envelope part is preferably
established. The first projected angle of incidence is preferably
established taking into account the projected angle of incidence on
December 21 in the provided application of the building envelope
part, which can be expedient in particular for a provided
application of the building envelope part on the northern
hemisphere. The first projected angle of incidence is established
by a mathematical expression that correlates the variables
.alpha..sub.+, .beta., .gamma., .epsilon. and .phi., preferably
according to the equation .alpha..sub.+=arcsin(cos(.phi.)*cos
(.gamma.))+(.beta.-90.degree.)-.epsilon., wherein .alpha..sub.+ is
the first projected angle of incidence, .beta. is an inclination
and .gamma. is an alignment of the building envelope part in the
provided application, and .epsilon. is the obliqueness of the
ecliptic relative to the equator. In particular, .epsilon. can be
about 23.4.degree.. Given such a first projected angle of incidence
calculated in particular using this equation, the building envelope
part can comparatively easily be dimensioned so as to efficiently
establish a spatial angle of incidence range intended to allow as
much transmittance through the building envelope part as
possible.
[0030] A second projected angle of incidence with a minimum light
transmittance through the building envelope part is preferably
established. The second projected angle of incidence is preferably
established taking into account the projected angle of incidence on
June 21 in the provided application of the building envelope part,
which can be expedient in particular for a provided application of
the building envelope part on the northern hemisphere. The second
projected angle of incidence is established by a mathematical
expression that correlates the variables .alpha..sub.-, .beta.,
.gamma., .epsilon. and .phi., preferably according to the equation
.alpha..sub.-=arcsin(cos(.phi.)cos(.gamma.))+(.beta.-90.degree.)-.epsilon-
., wherein .alpha..sub.- is the second projected angle of
incidence, .beta. is an inclination and .gamma. is an alignment of
the building envelope part in the provided application, and
.epsilon. is the obliqueness of the ecliptic relative to the
equator. Given such a second projected angle of incidence
calculated in particular using this equation, the building envelope
part can comparatively easily be dimensioned so as to efficiently
establish a spatial angle of incidence range intended to allow as
little transmittance through the building envelope part as
possible.
[0031] The building envelope part is preferably configured in such
a way that the outer structures in a common plane encompass
parallel arranged stripes, and the inner structures in a common
plane encompass parallel arranged stripes. The stripes of the outer
structures and inner structures can each exhibit straight sides and
a fixed width. This type of configuration for the outer structures
and inner structures enables a comparably simple, efficient
construction of the building envelope part. The building envelope
part is here configured in such a way that the outer structures are
arranged parallel to the inner structures, wherein the common plane
of the outer structures and common plane of the inner structures
are different, and that the stripes of the outer structures and
stripes of the inner structures are established by a mathematical
expression that correlates the variables r, d, .alpha..sub..+-. and
n, preferably formulated according to the equation
r d = sin ( .alpha. + ) n 2 - sin 2 ( .alpha. + ) - sin ( .alpha. -
) n 2 - sin 2 ( .alpha. - ) , ##EQU00004##
wherein r is the width of one of the stripes of the inner
structures, for example in [mm], d is the thickness of the building
envelope part, for example in [mm], n is the average refraction
index of the building envelope part, .alpha..sub.+ is the first
projected angle of incidence, and .alpha..sub.- is the second
projected angle of incidence. This type of configuration for the
outer structures and inner structures enables a comparatively
efficient, readily calculable construction of the building envelope
part. The building envelope part is preferably configured in such a
way that a width of the stripes of the exterior side, a width of
the stripes of the interior side, and a respective distance between
the stripes are essentially identically dimensioned. This type of
configuration can yield a preferred contrast ratio, wherein it is
also possible to deviate from such a configuration, for example, if
the building envelope part in its provided application is
preferably to have heating or cooling properties.
[0032] The outer structures are preferably designed to diffuse
light, wherein a light-diffusing effect for the outer structures is
provided in such a way that a light band passing through the
building envelope part is widened by a factor of roughly three from
the exterior side up to the interior side. This type of
configuration for the outer structures makes it comparatively easy
to manufacture an efficient building envelope part with light
diffusers as the outer structures as described above. However, the
mentioned expansion factor can also be differently configured
depending on the situation, wherein it can range from 2 to 5, for
example.
[0033] The outer structures and inner structures are preferably
given a lamellar design. For example, the term "lamellar" can be
understood as a parallel arrangement of stripes in a plane, wherein
these stripes exhibit straight sides and a specific width, for
example. This type of lamellar configuration for the outer
structures and inner structures enables a comparatively simple,
efficient construction and manufacture of the building envelope
part.
[0034] Another aspect of the invention relates to a computer
program, which exhibits program code means configured to at least
partially implement the method described above when the computer
program is run on a computer. This type of computer program makes
it possible to comparatively easily, quickly and precisely carry
out the method according to the invention. In addition, this type
of computer program makes it possible to implement and distribute
the method according to the invention in an expedient and efficient
manner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The building envelope part according to the invention and
the method according to the invention will be described in greater
detail below with reference to the attached drawings based upon
exemplary embodiments. Shown on:
[0036] FIG. 1 is a diagrammatic cross sectional view depicting part
of a first exemplary embodiment for a building envelope part
according to the invention;
[0037] FIG. 2 is a diagrammatic view on the building envelope part
from FIG. 1, for example for an east-oriented facade for a latitude
of the object location measuring 45.degree.;
[0038] FIG. 3 is a diagrammatic cross sectional view of the
building envelope part from FIG. 1 in a wintertime functional
mode;
[0039] FIG. 4 is a diagrammatic cross sectional view of the
building envelope part from FIG. 1 in a summertime functional
mode;
[0040] FIG. 5 is a diagrammatic cross sectional view depicting part
of a second exemplary embodiment for a building envelope part
according to the invention;
[0041] FIG. 6 is a diagrammatic cross sectional view depicting part
of a third exemplary embodiment for a building envelope part
according to the invention;
[0042] FIG. 7 is a diagrammatic cross sectional view depicting part
of a fourth exemplary embodiment for a building envelope part
according to the invention.
WAY(S) OF IMPLEMENTING THE INVENTION
[0043] FIG. 1 shows a glass pane 1 as a first exemplary embodiment
of a building envelope part according to the invention with an
outer surface 2 and an inner surface 3 opposite the outer surface
2. The outer surface 2 exhibits outer structures 21 with a fixed
width, as well as intermediate outer regions 22 lying between the
outer structures 21. The inner surface 3 exhibits inner structures
31 with a fixed width, as well as intermediate inner regions 32
lying between the inner structures 21.
[0044] The glass pane 1 is made out of a low-iron glass. The outer
structures 21 are formed by etching the glass pane 1, wherein the
intermediate outer regions 22 are left unchanged. The inner
structures 31 take the form of a mirror coating generated by means
of a printed silver layer on the glass pane 1, wherein the
intermediate inner regions 32 are also left unchanged.
[0045] The following stipulation applies with respect to the entire
remaining description. If reference numbers are contained in a
figure for purposes of graphic clarity, but not mentioned in the
immediately accompanying text of the description, reference is made
to their explanation in preceding descriptions of figures. In
addition, if reference numbers are mentioned in a text of the
description belonging directly to a figure but not contained in the
accompanying figure, reference is made to the preceding
figures.
[0046] FIG. 2 shows the glass pane 1 as viewed from outside. The
outer surface 2 and inner surface 3 are here bordered by four side
edges 5. The glass pane 1 has a rectangular design. The outer
structures 21 as well as the inner structures 31 of the glass pane
1 are configured as comparatively narrow, parallel stripes, which
run at differing inclinations depending on the cardinal direction
and location of a provided application for the glass pane 1. In
other words, tailored to the respective circumstances, the parallel
stripes or the outer structures 21 and inner structures 31 define a
more or less acute angle co with the side edges 5. The degrees of
freedom are essentially as follows when configuring the parallel
stripes: The width of the diffusely scattering stripes, i.e., of
the outer structures 21, relative to the glass thickness; the width
between the diffusely scattering stripes, i.e., the intermediate
outer regions 22, relative to the glass thickness; the degree of
diffusion for the outer structures 21 that defines the spatial
dispersion of the incident light; the width of the mirroring
stripes, i.e., of the inner structures, relative to the glass
thickness; the relative position of diffusely scattering to
mirroring or absorbing stripes or of outer structures to inner
structures relative to the glass thickness; and the acute angle
.omega..sub.1 at which the stripes run relative to the horizontal
side edge 5.
[0047] FIG. 3 shows how the glass pane 1 functions in winter. As
evident, solar radiation 4 strikes the outer surface 2 of the glass
pane 1 in a specific first spatial angle of incidence range. The
solar radiation 4 is refracted at the intermediate outer regions 22
in a conventional manner in accordance with the refraction index of
glass, and then penetrates through the glass pane 1 up until its
inner surface 3. The solar radiation 4 is scattered on the outer
structures 21, and again penetrates through the glass pane 1 in the
direction of the outer surface 2 or to the outside. The outer
structures 21 are arranged relative to the inner structures 31 in
such a way that allows comparatively abundant solar radiation 4 to
penetrate through the glass pane 1 directly through the
intermediate outer regions 22 via the intermediate inner regions 32
through the glass pane 1. The scattering effect of the outer
structures 21 also causes additional solar radiation 4 to penetrate
through the glass pane 1 via the intermediate inner regions 32 in
the first spatial angle of incidence range, so that comparatively
abundant solar radiation 4 can penetrate through the glass pane 1
in winter.
[0048] FIG. 4 shows how the glass pane 1 functions in summer. As
evident, solar radiation 4 strikes the outer surface of the glass
pane 1 in a specific second spatial angle of incidence range. The
solar radiation 4 is again refracted at the intermediate outer
regions 22 in a conventional manner, and then penetrates through
the glass pane 1 up until its inner surface 3. The solar radiation
4 is scattered on the outer structures 21, and penetrates through
the glass pane 1 up until its inner surface 3. The solar radiation
4 is reflected on the inner structures 31, and then penetrates the
glass pane 1 through the outer surface 2 toward the outside. The
outer structures 21 are arranged relative to the inner structures
31 in such a way that comparatively little solar radiation 4 can
penetrate through the glass pane 1 directly through the
intermediate outer regions 22 via the intermediate inner regions 32
through the glass pane 1. The scattering effect of the outer
structures 21 also causes additional solar radiation 4 to strike
the reflecting inner structures 31, so that comparatively little
solar radiation 4 can penetrate through the glass pane 1 in
summer.
[0049] FIG. 5 shows a glass pane 19 as a second exemplary
embodiment of a building envelope part according to the invention
with an outer surface 29 and an inner surface 39 opposite the outer
surface 29. The outer surface 29 exhibits outer structures 219 with
a fixed width, as well as intermediate outer regions 229 that lie
between the outer structures 219. The inner surface 39 exhibits
inner structures 319 with a fixed width, as well as intermediate
inner regions 329 that lie between the inner structures 219.
[0050] The glass pane 19 is essentially designed to correspond to
the glass pane 1 shown on FIG. 1 to FIG. 4. In particular, the
glass panes 1, 19 described above as well as those described below
(see glass pane 18 on FIG. 6 and glass pane 17 on FIG. 7) are here
preferably dimensioned and manufactured via the following
steps:
[0051] The axial rotation .omega. of any angle-selective outer and
inner structures is geared toward the orientation, i.e., the
alignment and inclination, of the glass pane 1, 19, 18, 17 in its
provided application, as well as toward the latitude of the object
location at which the glass pane is being used. If the glass pane
1, 19, 18, 17 can receive direct solar radiation on all days in a
calendar year, the longitudinal axis of the outer and inner
structures must be aligned parallel to the intersecting line
between the solar ecliptic and glass pane 1, 19, 18, 17, and
otherwise perpendicular. The latter holds true in particular on the
northern hemisphere in winter for glass panes 1, 19, 18, 17 or
building envelope parts aligned toward the north. The following
relationship applies to glass panes 1, 19, 18, 17: A mathematical
expression that correlates the variables .omega., .beta., .gamma.
and .phi.,
.omega. = - sgn ( .phi. * sin ( .gamma. ) ) * arccos ( sin ( .phi.
) * sin ( .beta. ) + cos ( .phi. ) * cos ( .beta. ) * cos ( .gamma.
) cos ( .phi. ) * cos ( .beta. ) + sin ( .phi. ) * cos ( .gamma. )
* sin ( .beta. ) ) 2 + sin 2 ( .gamma. ) * sin 2 ( .beta. ) ) ( 1 )
##EQU00005##
[0052] In this case, .beta. is an inclination of the glass pane 1,
19, 18, 17, .gamma. is an alignment of the glass pane 1, 19, 18,
17, and .phi. is the latitude of the object location.
[0053] The angular dependence of the outer and inner structures in
a transversal axial direction can be achieved in a variety of ways,
for example through the geometric or structural configuration of
the glass pane 1, 19, 18, 17. As described above, the angle
.alpha..sub.+ at which a maximum or minimum transmittance is to be
achieved must first be determined for this purpose given a parallel
and perpendicular alignment. These two angles are reached on June
21 and December 21, when the respective solar azimuth and alignment
of the glass pane 1, 19, 18, 17 coincide, and described by
mathematical expressions that correlate the variables
.alpha..sub..+-., .beta., .gamma., .epsilon. and .phi., preferably
in accordance with the following equations:
.alpha..sub..+-.=arcsin(cos(.phi.)*cos(.gamma.))+(.beta.-90.degree.).+-.-
.epsilon., (2)
wherein .epsilon..apprxeq.23.4.degree. is the obliqueness of the
ecliptic relative to the equator, which is also referred to as the
tilt of the earth's axis or obliquity. The outer structures and
inner structures described above and below will be used in the
following to illustrate configurations that yield comparatively
high contrast ratios for the angles .alpha..sub.+ (continuous
lines) and .alpha..sub.- (broken lines).
[0054] In the glass pane on FIG. 4, stripes are applied as the
outer structures 219 to the outer surface 29 (air side) parallel to
the longitudinal axis through printing, etching, sandblasting,
roughening or in some other way, and diffusely scatter the incident
light or incident solar radiation 49. The sections between the
stripes, i.e., the intermediate outer regions 229, are left
unchanged. Stripes are also applied as the inner structures 319 on
the inner surface 39 of the glass pane parallel to the longitudinal
axis through printing or in some other way, and reflect or absorb
the incident light or incident solar radiation 49. The sections
between the stripes, i.e., the intermediate inner regions 329, are
left unchanged. The width and relative location of the upper and
lower stripes, i.e., the outer structures 21 and inner structures
31, of the glass pane must be selected in such a way that the light
falling through the clear sections, i.e., the intermediate outer
regions 229, from outside or above, in turn passes through the
clear sections below, i.e., the intermediate inner regions 329, at
the angle .alpha..sub.+ and the light falling through the clear
sections, i.e., the intermediate outer regions 229, from outside or
above, in turn strikes the reflecting sections below, i.e., the
inner structures 319, at the angle .alpha..sub.-. The respective
light refraction of the glass must here be taken into account by a
mathematical expression that correlates the variables r, d,
.alpha..sub..+-. and n, preferably in accordance with the
equation
r d = sin ( .alpha. + ) n 2 - sin 2 ( .alpha. + ) - sin ( .alpha. -
) n 2 - sin 2 ( .alpha. - ) , ( 3 ) ##EQU00006##
wherein d [mm] is the thickness of the glass or glass pane 19, r
[mm] is the width of the reflector or inner structures 319, and n
is the average refraction index of glass. The second summand in the
above equation indicates the offset in outer and inner structures
x/d. The scattering effect of the diffuse stripes or outer
structures 219 with width m [mm] must be selected in such a way as
to widen the incident light band by about a factor of three as it
passes through the glass thickness.
[0055] FIG. 6 shows the glass pane 18 as a third exemplary
embodiment of a building envelope part according to the invention
with an outer surface 28 and an inner surface 38 opposite the outer
surface 28. The outer surface 28 exhibits prismatic outer
structures 218 with a fixed width. The inner surface 38 exhibits
inner structures 318 with a fixed width, as well as intermediate
inner regions 328 that lie between the inner structures 218. The
outer structures 218 designed as flat prisms on the outer surface
of the glass pane guide the light bands or solar radiation incident
at angles .alpha..sub.+ or .alpha..sub.- in the direction of the
reflectors or inner structures 318 via light diffraction to a
maximum or minimum extent.
[0056] FIG. 7 shows a glass pane 17 as a fourth exemplary
embodiment of a building envelope part according to the invention
with an outer surface 27 and an inner surface 37 opposite the outer
surface 27. The outer surface 27 exhibits outer structures 217, as
well as intermediate outer regions 227 that lie between the outer
structures 217. The outer structures 217 protrude through the glass
pane 17, and extend from the outer surface 27 up until the inner
surface 37. The inner surface 37 exhibits inner structures 317 with
a fixed width, as well as intermediate inner regions 327 that lie
between the inner structures 217. The outer structures 217 are each
joined with one of the inner structures 317, so that they together
each exhibit an essentially L-shaped cross section.
[0057] The outer structures 217 and inner structures 317 designed
as L-shaped lamellae allow the light bands or solar radiation 47
incident at angles .alpha..sub.+ or .alpha..sub.- to be maximally
passed through or reflected by the construction or glass pane 17
owing to reflections. In the case of
.alpha..sub.+=-.alpha..sub.- (4)
where x=0 mm, the contrast ratio is maximal (full transmittance or
full reflection). At
x d = sin ( ( .alpha. + + .alpha. - ) / 4 ) ( 5 ) ##EQU00007##
an optimal contrast ratio is reached for
.alpha..sub.+.noteq.-.alpha..sub.-.
[0058] Even though the invention was depicted and detailed based on
the figures and accompanying specification, this depiction and
detailed description must be regarded as illustrative and
exemplary, and not construed as limiting the invention. It goes
without saying that a person skilled in the art can introduce
changes and modifications without departing from the scope and
spirit of the following claims. In particular, the invention also
encompasses embodiments with any combination of features mentioned
or shown above or below in relation to various embodiments. For
example, the invention can also be realized by the following
additional variations in structural design: [0059] Given an
analogue construction as described above with respect to FIG. 5,
using light-polarized stripes as outer structures and inner
structures that are complementarily polarized for c and r, the
transmittance can be maximal at an angle .alpha..sub.+ and drop off
approximately or entirely to zero at an angle .alpha..sub.-. [0060]
The disclosed arrangements and configurations of outer structures
and inner structures, in particular those described above on FIG.
5, FIG. 6 and FIG. 7, can advantageously also be arranged in such a
way as not to form an acute angle with one of the side edges. They
can also be situated horizontally.
[0061] The invention also encompasses individual features in the
figures, even if they are there shown in conjunction with other
features and/or not mentioned above or below. In addition, the
subject matter of the invention can exclude the alternative
embodiments described in the figures and specification, and
individual alternative features thereof.
[0062] Furthermore, the term "encompass" or "comprise" and
derivations thereof does not preclude other elements or steps.
Likewise, the indeterminate article "a" or "an" and derivations
thereof does not rule out a plurality. The functions of several
features enumerated in the claims can be satisfied by a single
unit. In particular, the terms "essentially", "roughly",
"approximately" and the like in conjunction with a property or
value also precisely define the property or precisely define the
value. A computer program can be stored and/or run on a suitable
medium, for example on an optical storage medium or a fixed medium,
which is provided together with or as part of other hardware. It
can also be run in another form, for example via the internet or
other wired or wireless telecommunication systems. In particular,
for example, a computer program can be a computer program product
that is stored on a computer-readable medium, and designed to be
executed to implement a method, especially the method according to
the invention. All reference numbers in the claims are not to be
construed as limiting the scope of the claims.
* * * * *