U.S. patent application number 10/971981 was filed with the patent office on 2005-03-10 for optical colored glasses.
Invention is credited to Hentschel, Ruediger, Kolberg, Uwe, Ritter, Simone.
Application Number | 20050054515 10/971981 |
Document ID | / |
Family ID | 7696221 |
Filed Date | 2005-03-10 |
United States Patent
Application |
20050054515 |
Kind Code |
A1 |
Kolberg, Uwe ; et
al. |
March 10, 2005 |
Optical colored glasses
Abstract
The invention concerns an optical colored glass of the
composition (in % in weight on oxide basis) SiO.sub.2 50-62;
K.sub.2O 10-25; Na.sub.2O 0-14; Al.sub.2O.sub.3 0-2; B.sub.2O.sub.3
3-5; ZnO 13.5-37; F 0-1; TiO.sub.2 0-7; In.sub.2O.sub.3 0-2;
Ga.sub.2O.sub.3 0-2; SO.sub.3 0-1; SeO.sub.2 0-1; C 0-1;
M.sup.IM.sup.IIIY.sub.2.sup.II 0.1-3, whereby M.sup.I=Cu+ and/or
Ag+ and/or M.sup.III=In.sup.3+ and/or Ga.sup.3+ and/or Al.sup.3+
and/or Y.sup.II=S.sup.2- and/or Se.sup.2- and at least 0.1% in
weight of the oxide (M.sub.2O.sub.3) of the M.sup.III, which is/ar
present in M.sup.IM.sup.IIIY.sup.II.sub.2, and with at least 0.2%
in weight of the oxide, of Y.sup.II, which/are present in
M.sup.IM.sup.IIIY.sup.II.sub.2.
Inventors: |
Kolberg, Uwe; (Mainz-Kastel,
DE) ; Hentschel, Ruediger; (Bodenheim, DE) ;
Ritter, Simone; (Mainz, DE) |
Correspondence
Address: |
BAKER & DANIELS
111 E. WAYNE STREET
SUITE 800
FORT WAYNE
IN
46802
|
Family ID: |
7696221 |
Appl. No.: |
10/971981 |
Filed: |
October 22, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10971981 |
Oct 22, 2004 |
|
|
|
10224071 |
Aug 20, 2002 |
|
|
|
Current U.S.
Class: |
501/72 ; 501/65;
501/67 |
Current CPC
Class: |
C03C 4/02 20130101; C03C
3/093 20130101; Y10S 501/90 20130101; C03C 3/089 20130101; C03C
4/08 20130101; C03C 14/006 20130101 |
Class at
Publication: |
501/072 ;
501/065; 501/067 |
International
Class: |
C03C 003/078; C03C
003/089; C03C 003/093 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 22, 2001 |
DE |
101 41 101.4 |
Claims
1-20. (canceled)
21. A method of using a glass comprising: providing an optical
colored glass having
3 SiO.sub.2 50-62 K.sub.2O 10-25 Na.sub.2O 0-14 Al.sub.2O.sub.3 0-2
B.sub.2O.sub.3 3-5 ZnO 13.5-37 F 0-1 TiO.sub.2 0-7 In.sub.2O.sub.3
0-2 Ga.sub.2O.sub.3 0-2 SO.sub.3 0-1 SeO.sub.2 0-1 C 0-1 M.sup.I
M.sup.III Y.sup.II.sub.2 0.1-3
whereby M.sup.I=Cu.sup.+ and/or Ag.sup.+M.sup.III=In.sup.3+ and/or
Ga.sup.3+ and/or Al.sup.3+, Y.sup.II=S.sup.2- and/or Se.sup.2-with
at least 0.1% in weight of the oxide (M.sub.2O.sub.3) of the
M.sup.III which is/are present in M.sup.I M.sup.III Y.sup.II.sub.2,
and with at least 0.2% in weight of the oxide, of Y.sup.II, which
is/are present in M.sup.I M.sup.III Y.sup.II.sub.2, as well as
usual refining media if necessary in usual quantities; and using
said glass as an optical square edge filter.
22. A method of using a glass comprising: producing an optical
colored glass of the composition range
4 SiO.sub.2 50-62 K.sub.2O 10-25 Na.sub.2O 0-14 MgO 0-4 CaO 0-10
BaO 0-10 SrO 0-10 P.sub.2O.sub.5 0-10 Al.sub.2O.sub.3 0-2
B.sub.2O.sub.3 3-5 ZnO 13.5-37 F 0-1 TiO.sub.2 0-7 In.sub.2O.sub.3
0-2 Ga.sub.2O.sub.3 0-2 SO.sub.3 0-1 SeO.sub.2 0-1 C 0-1 M.sup.I
M.sup.III Y.sup.II.sub.2 0.1-1
whereby M.sup.I=Cu.sup.+, Ag.sup.+M.sup.III=In.sup.3+, Ga.sup.3+,
Al.sup.3+Y.sup.II=S.sup.2-, Se.sup.2-with at least 0.1% in weight
of the oxide (M.sub.2O.sub.3) of the M'" which is/are present in
M.sup.IM.sup.IIIY.sup.II.sub.2, and with at least 0.2% in weight of
the oxide, of Y.sup.II, which is/are present in M.sup.I M.sup.III
Y.sup.II.sub.2, as well as usual refining media if necessary in
usual quantities, with the process steps glass batch preparation,
melting of the glass, cooling, warming up, whereby 0.1-4% in weight
ZnS and/or ZnSe are added to the glass batch; and using said glass
as an optical square edge filter.
Description
[0001] The subject of the invention is an optical colored glass,
its use as optical square edge filter as well as an optical square
edge filter. The subject of the invention is also a procedure for
the production of optical colored glasses.
[0002] Optical square edge filters are characterized by
characteristic transmission properties. Thus ones with long pass
characteristic show a low transmission in the short-wave range,
which rises over a narrow spectral region to high transmission and
remains high in the long-wave range. The range of low transmission
(pure transmission value .sub.is# 10.sup.-) is called stop band,
the range of high transmission (pure transmission value .sub.ip
0.99) as pass range or pass band.
[0003] Optical square edge filters are characterized by means of
certain parameters. Thus the absorption edge of such a filter is
usually indicated as the so-called edge wavelength 8C. It
corresponds to the wavelength, for which the spectral pure
transmission factor between stop band and pass band amounts to half
of the maximum value.
[0004] Optical square edge filters are usually realized by colored
glasses, in which through colloidal elimination of semiconductor
compounds during the cooling of the molten mass or through
additional thermal treatment the coloring is produced. One speaks
of so-called tarnish glasses.
[0005] Commercial square edge filters are manufactured by doping
the basic glasses with cadmium semiconductor compounds. Depending
upon the edge position CdS, CdSe, CdTe or also mixed compounds of
these semiconductors are used for this. With these square edge
filters edge wavelengths of a maximum of 850 nm can be reached. In
addition, for the use e.g. in IR cameras or as laser protecting
glass longer-wave square edges are desired. Due to the toxic and
the carcinogenic characteristics of cadmium it is desired to be
able to do without these compounds and to use other doping factors
instead. In order to achieve equal or similar absorption properties
of the glasses, alternative doping factors must likewise consist of
semiconductors with direct optical transitions, because only
through the special band structure of the semiconductors, the
energy gap between valence band and conduction band, the sharp
transitions between absorption range and transmission range of the
glasses and thus to the filter characteristics of these glasses
take place.
[0006] The I-III-VI semiconductor system, e.g.
copper-indium-bisulfide and copper-indium-biselenide could also
represent an alternative to the CdS -, CdSe -, CdTe-compounds.
These for a long time well-known semiconductors are so far only of
greater practical importance in the photovoltaic.
[0007] In a number of Russian and Soviet patent applications for a
very close glass composition range are already CuInS.sub.2 doped
and/or CuInS.sub.2-CuInSe.sub.2 mix doped glasses described, which
are supposed to be applied as filters: SU 167702A1, SU 1527199A1,
RU 2073657C1, SU 1770297A1, SU 1770298A1, SU 1678786A1, SU
1678785A1, SU 1701658A1, SU 1677025, SU 1675239A1, SU 1675240A1 and
SU 1787963A1. All these glasses have in common that they contain no
or very little B.sub.2O.sub.3 and no or very little ZnO and that
they have with portions of up to 79% in weight a high SiO.sub.2
content. The glasses of these applications do not possess good
chemical stabilities.
[0008] It is subject of the invention to make chemically resistant
optical Cd-free colored glasses available, which possess square
edge characteristics and exhibit absorption edges between >0.4
.mu.m and 1.2 .mu.m.
[0009] It is further a subject of the invention to make such square
edge filters available.
[0010] It is further a subject of the invention to make a procedure
available for the production of optical colored glasses.
[0011] The tasks are solved through a glass according to claim 1, a
procedure according to claim 9, a usage according to claim 10 and a
square edge filter according to claim 11.
[0012] Alkali-zinc-silicate-glass serves as basic glass. The basic
glass is based on the oxides SiO.sub.2, which have the function of
forming the structure, ZnO, which has the function of forming the
structure and transforming the structure, and K.sub.2O and optional
Na.sub.2O, which have the function of transforming the
structure.
[0013] SiO.sub.2 constitutes the main part of the glass with 50 to
62% in weight. Higher portions would increase the crystallization
tendency and would worsen the fusibility.
[0014] ZnO is present with 13.5 to 37% in weight. It increases the
resistance to thermal shock of the glass, a characteristic, which
is substantial for the intended use of the glass behind or in front
of strong radiation sources, which are always accompanied by a high
temperature emission. ZnO supports in addition the homogeneous
nano-crystallization of the doping material in the glass. I.e.
during the warming up of the glass in such a way homogeneous
crystal growth of the semiconductor doping factors is ensured. The
very pure and bright color and the sharp absorption edge of the
glasses result from these mono dispersive crystallites. With ZnO
contents lower than 13.5% in weight the glasses show a worse or no
tarnish behavior. A ZnO portion of at least 18% in weight is
preferred. The mentioned upper limit of ZnO is meaningful, since
glasses, which exhibit a higher ZnO content, have a tendency for
the formation of drip-like elimination areas and thus for
separation. The separation tendency of such "Zinc-silicate glasses"
can be lowered by the use of the structure transformer K.sub.2O. In
order to prevent micro elimination of ZnO enriched areas and to
reduce their processing temperature, the glasses contain 10 to 25%
in weight, preferably 18 to 25% in weight K.sub.2O. The glass can
contain in addition up to 14% in weight Na.sub.2O, which affects
mainly the physical characteristics like the fixed viscosity
reference points and the coefficients of expansion. With higher
concentration of Na.sub.2O the chemical stability would decrease,
the coefficient of expansion would be too high and the
transformation temperature would be too low. Preferably the sum of
amounts of K.sub.2O and Na.sub.2O are 29% in weight at the most.
The other expensive alkali oxides Li.sub.2O, Rb.sub.2O, Cs.sub.2O
can in principle also be used, however due to their price
disadvantage they are preferably are not used.
[0015] Besides ZnO also B.sub.2O.sub.3 promotes the resistance to
thermal shock of the glass. B.sub.2O.sub.3 is contained with 3 to
5% in weight in the glass. B.sub.2O.sub.3 improves the fusibility
of the glass.
[0016] The glass can contain further up to 1% in weight F. F serves
for the improvement of the fusibility, i.e. it lowers the viscosity
of the glass.
[0017] The glass can contain also up to 1% in weight C. C serves as
reducing agent, in order to prevent an oxidation of the compound
semiconductors.
[0018] The glass is suitable in an outstanding fashion for the
formation of nano-crystals from compound semiconductors of the
class I-III-VI which is distributed colloidal in the glass.
[0019] The nano-crystallization is affected during the tarnish
process by the glass viscosity, the oversaturation, the solubility
product and the growth rate of the color carriers. The tarnish
process, which contains the coloring and thus the elimination of
the crystallites of the semiconductor compounds, takes place either
already at the cooling of the glasses and/or through a further
temperature treatment within the range Tg # 200K. The tarnish
temperature and tarnish times thereby affect the crystallite size.
The larger the crystallites become, the smaller becomes the band
gap of the semiconductors and the more longer-waved (=red) is the
inherent color of the glass. The specialist knows how to control
these factors if possible.
[0020] The glasses contain the compound semiconductors M.sup.I
M.sup.III Y.sup.II.sub.2 (whereby M.sup.I=Cu.sup.+, Ag.sup.+,
M.sup.III=In.sup.3+, Ga.sup.3+, Al.sup.3+, Y.sup.II=S.sup.2-,
Se.sup.2- can be) as chromophore components, thus as doping factors
to impart the filter characteristics.
[0021] The sum of the compound semiconductors in the glass amounts
to at least 0.1% in weight, which corresponds to the minimum
concentration of colloidal micro crystals distributed in the glass
for the light absorption, and at the most 3% in weight, preferably
at the most 1% in weight. Higher contents than 3% in weight would
lower the transmission within the pass range after the tarnish
process in an unacceptable manner. From the mentioned ternary
semiconductor systems M.sup.I M.sup.III Y.sup.II.sub.2 are all edge
components, thus e.g. CuInS.sub.2, CuInSe.sub.2, CuGaS.sub.2,
CuGaSe.sub.2, AgInS.sub.2, AgInSe.sub.2, AgGaS.sub.2 and
AgGaSe.sub.2 as well as all mixed compounds of two component
systems or multi component systems usable. It is also possible to
use two or several edge components at the same time.
[0022] Doping factors of one or several components from the system
CuIn(Se.sub.1-x S.sub.x).sub.2 with x=0 to 1, i.e. of the edge
components CuInSe.sub.2 and CuInS.sub.2 as well as by their mixed
compounds are particularly preferable. Particularly preferable is a
doping factor content from 0.1 to 0.5% in weight.
[0023] The absorption edge in the area between 360 nm to 1200 nm
can be shifted by variations of the portions of the respective
compounds and the conditions of the tarnish process. With doping
factor contents between 0.1 and 0.5% in weight, in particular
CuIn(Se.sub.1x S.sub.x).sub.2 edge lengths between 400 nm and 1200
nm can be achieved.
[0024] For the characteristics as tarnish gas the components
In.sub.2O.sub.3 and Ga.sub.2O.sub.3 with contents of 0-2% in weight
in each case as well as SO.sub.3 and SeO.sub.2 with contents of
0-1% in weight are very favorable. These components prevent
possible evaporations of the components In.sub.2O.sub.3,
Ga.sub.2O.sub.3, S and Se from the compound semiconductors. Thus
the chalcopyrite remains as the chromophore component in or close
to the intended stoichiometry and thus at the desired specific edge
position. Therefore the glasses contain at least 0.1% in weight of
the oxide of the M.sup.III, thus M.sub.2O.sub.3, which is/are
present in M.sup.I M.sup.III Y.sup.II.sub.2, and at least 0.2% in
nweight of the oxide of Y.sup.II, which is/are present in M.sup.I
M.sup.III Y.sup.II.sub.2.
[0025] It is particularly preferable, to use SO.sub.3 and/or
SeO.sub.2 not with elemental S and/or Se but in the form of ZnS
and/or ZnSe. Preferable 0.1-4% in weight ZnS and/or ZnSe are used.
Both components promote the structure of the chromophore crystals
of the semiconductor compounds such as CuInS.sub.2 and CuInSe.sub.2
as auxiliary crystal components and thus the edge steepness and the
transmission in the pass range.
[0026] With this procedure for the production of optical colored
glasses of the composition range (in % in weight on oxide basis)
SiO.sub.2 50-62, K.sub.2O 10-25; Na.sub.2O 0-14; MgO 0-4; CaO 0-10,
BaO 0-10, SrO 0-10; P.sub.2O.sub.5 0-10; Al.sub.2O.sub.3 0-2;
B.sub.2O.sub.3 3-5; ZnO 13.5-37; F 0-1, TiO.sub.2 0-7;
In.sub.2O.sub.3 0-2; Ga.sub.2O.sub.3 0-2; SO.sub.3 0-1; SeO.sub.2
0-1; C 0-1; and the doping factor M.sup.I M.sup.III Y.sup.II.sub.2
with M.sup.I=Cu.sup.+Ag.sup.+, M.sup.III=In.sup.3+, Ga.sup.3+,
Ga.sup.3+, Al.sup.3+, Y"=S.sup.2-, Se.sup.3- with at least 0.1% in
weight of the oxide (M.sub.2O.sub.3) of the M.sup.III, which is/are
present in M.sup.I M.sup.III Y.sup.II.sub.2, and with at least 0.2%
in weight of the oxide, or Y", which is/are present in M.sup.I
M.sup.III Y.sup.II.sub.2, with the process steps glass batch
preparation, melting of the glass, cooling and warming up, with
which 0.1- 4% in weight ZnS and/or ZnSe are added to the glass
batch, tarnish glasses with defined edge length can be manufactured
easily, purposeful and reproducible. The requirements of the to be
met conditions regarding temperature and time of the process steps
cooling and warming up are smaller than with conventional
procedures. The term melting here combines the steps refining,
homogenizing and conditioning for further processing, which follow
the melting itself.
[0027] In addition the glass can contain up to 4% in weight MgO, up
to 10% in weight CaO, up to 10% in weight BaO, up to 10% in weight
SrO, up to 10% in weight P.sub.2O.sub.5, up to 2% in weight
Al.sub.2O.sub.3 and up to 7% in weight TiO.sub.2. Al.sub.2O.sub.3
improves the crystallization ability of the glass, MgO and CaO
function in the basic glass similar to ZnO. They improve the
chemical stability, and they are less expensive than ZnO. BaO and
SrO serve for the fine tuning of the coefficient of expansion,
transformation temperature and processing temperature. However,
since BaO and SrO are more expensive than MgO and SrO, which are
similar in many properties, they are preferably not used.
[0028] P2O5 can partially be exchanged against SiO2 or B2O3 as
structure formers. It is useful for the lowering of the viscosity
at certain temperatures. P2O5 reduces however the chemical
resistance and is therefore preferably not used.
[0029] The component TiO2 in this glass system takes over mainly
the function of the supporting UV-blocking. Square edge filters
must fulfill an optical density in the stop band. Additional UV
absorbers such as TiO2 can support this.
[0030] The glasses can be molten with the help of the well-known
usual melting procedures for tarnish glasses, i.e. under neutral
and/or reducing conditions at temperatures of approx.
1100-1550.degree. C. The glasses build already during the cooling
process and/or through an additional temperature treatment finely
divided nano-crystallites, which cause the color and/or a
tarnishing of the glass.
[0031] For the improvement of the glass quality, one or more
well-known refining media in the usual quantities can be added to
the glass batch for the refining of the glass. Thus the glass
exhibits a particularly good internal glass quality regarding the
non-existence of bubbles and streaks.
EXAMPLES
[0032] Six examples of glasses according to the invention were
molten from the usual optical raw materials. The raw materials were
weighed, afterwards mixed thoroughly, melted in usual procedures
with approx. 1300.degree. C. to 1550.degree. C. and well
homogenized. The temperature at pouring was approx. 1450.degree.
C.
[0033] In Table 2 the following are indicated: the respective
composition (in % in weight) and the edge wavelength .sup.8c [nm]
(sample thickness d=3 mm), tarnish temperatures [.degree. C.] and
rise times [h].
[0034] Table 1 shows a melting example, for the glass in accordance
with example 1 from Table 2. The glass was cooled with 20 K/h and
afterwards temperature treated for 3 h at approx. 560.degree. C.
The glass possesses an edge wavelength .sup.8.sub.c of 420 nm.
1TABLE 1 Melting example of a 0.5-l-glass batch Originally
weighted-in Component % in weight Raw material quantity [g]
SiO.sub.2 52.84 SiO.sub.2 524.67 B.sub.2O.sub.3 4.07 B.sub.2O.sub.3
40.80 ZnO 19.71 ZnO 194.96 K.sub.2O 22.84 K.sub.2CO.sub.3 332.91
SO.sub.3 0.1 ZnS 1.02 CuInSe.sub.2 0.23 CuInSe.sub.2 2.55
[0035]
2TABLE 2 Glass composition (in % in weight), edge wavelength
8.sub.C, tarnish temperature [.degree. C.] and tarnish time [h]
(the difference to 100% results from taking into account
CuInS.sub.2/CuInSe.sub.2 as CuO, In.sub.2O.sub.3,
SO.sub.3/SeO.sub.2) 1 2 3 4 5 6 SiO.sub.2 52.84 52.9 52.5 52 61.95
52.75 B.sub.2O.sub.3 4.07 4.07 4.05 4 3 4.05 ZnO 19.71 19.74 19.64
19.4 13.99 19.68 Na.sub.2O -- -- -- -- 8.99 -- K.sub.2O 22.84 22.86
22.75 22.47 11.59 22.8 SO.sub.3 0.1 0.16 -- -- 0.21 -- CuInS.sub.2
-- 0.22 -- 1 0.22 0.091 CuInSe.sub.2 0.23 -- 0.5 -- -- 0.094 C --
-- -- -- 0.05 -- 8.sub.C [nm] d = 3 mm, 420 324 507 1010 780 416
(tarnish temperature (560/3) (--/0) (--/0) (--/0) (--/0) (--/0)
[.degree. C.]/tarnish time [h]) 8.sub.C [nm] d = 3 mm, 460 415 613
1030 898 -- (tarnish temperature (560/57) (500/150) (560/57)
(590/150) (595/50) [.degree. C.]/tarnish time [h]) 8.sub.C [nm] d =
3 mm, -- 521 -- -- 960 -- (tarnish temperature (515/150) (610/150)
[.degree. C.]/tarnish time [h])
[0036] The glasses according to the invention and the glasses
manufactured in the procedure according to the invention are
especially suitable for the use as optical square edge filters with
long pass characteristic due to their transmission course. They
show in the stop band a good optical density of 3, whereby the
optical density is defined as OD (8)=1 g (1/(8)). Their
transmission in approximately the pass band, which is longer-waved
compared to the stop band, is sufficiently high with 88%. Their
absorption edge is sufficiently steep. It can be moved with M.sup.I
M.sup.III Y.sup.II doped glasses, for which is M.sup.I=Cu.sup.+,
Ag.sup.+, M.sup.III=In.sup.3+, Ga.sup.3+, Y.sup.II=S.sup.2-,
Se.sup.2- between 400 nm and 1200 nm. Therefore the glasses cover
with the area of edge position of the usual Cd-containing tarnish
glasses as far as possible and go in the long-wave are far beyond
these.
[0037] If the glasses contain aluminum doping factors, thus
M.sup.I-Al (S, Se) compound semiconductors like e.g. CuAlS.sub.2
and CuAlSe.sub.2 or their mixed components alone or in combination
with the other mentioned M' M" Y" systems, then edge lengths up to
a minimum of 360 nm are produced.
[0038] When using exclusively the M.sup.I-Al--(S, Se) doping
factors, preferably the Cu--Al--(S,Se) doping factor, edge lengths
between 460 nm and 360 nm is produced preferably between 0.1 and
0.5% in weight.
[0039] FIG. 1 shows the transmissions course (transmission factor
versus wave length 8) at samples of the thickness 3 mm of the
examples 1 and 2 (reference numbers 2 and 3) as well as a
comparison example (reference number 1). The comparison example is
the commercially available Cd-containing glass GG 420 of the
applicant.
[0040] The glasses according to the invention are environmental
friendly, as they do not need any Cd-containing components. Due to
their composition they can be easily melted, they are chemically
resistant and resistant to thermal shock.
[0041] Their tarnish behavior is easily controllable. This applies
in particular to the glasses manufactured in the procedure
according to the invention, which exhibit steep absorption
edges.
* * * * *