DE2321356C3 - Optical borosilicate glass of the system SiO deep 2 -B deep 2 O deep 3 -BaO-PbO-La deep 2 O deep 3 with v deep d -1.68 to 1.72 and v deep d = 43 to 48 - Google Patents

Description

It contains glasses of the specified system

2. Optical borosilicate glass according to claim 1, of similar composition known, with which the characterized in that the molten salt can be achieved for the 20 mentioned optical values. Reduction of the refractive index an addition of up to These contain additional components or contain up to 5 percent by weight of Al ₂ O ₃ . one or the other component of the invented

3. Optical borosilicate glass according to claim 1 glass according to the invention. As a result, the other and 2 are, characterized in that the melting properties of the glasses concerned, such as B. sentence to increase the dispersion an additive 25 the tendency to crystallize, the chemical behavior of up to 5 weight percent WO ₃ contains. and the toughness is much less favorable.

4. Optical borosilicate glass according to claim 1 The object set is achieved in that the to 3, characterized in that the melting melt set according to the invention

set contains as a known refining agent As ₂ O ₃ . 30th

18.9-22 percent by weight -15.6 percent by weight SiO ₂ , 10 - 43 percent by weight B ₂ O ₃ , 39 -14 percent by weight BaO, 8th -10 percent by weight La ₂ O ₃ , 4th - 8 percent by weight PbO, 4th - 5 percent by weight CaO and 1 TiO ₂

System 35 borosilicate glass

SiO ₂ - B ₂ O ₃ - BaO - PbO - La ₂ O ₃

with n _d = 1.68 to 1.72 and v _ä = 43 to 48.

For the development of modern lens systems for refractive power reduction, the melting unit

the photo, telescope and measuring technology will contain up to 40 weight percent Al ₂ O _{3 in} addition to 40,

the glasses of extreme optical position with high

Refractive index with the lowest possible dispersion also contain a rate of up to 5% WO ₃ .

Combination glasses with similar refractive indices, each

but needed with higher dispersion. known refining agents, such as. B. As ₈ O ₃ added

For the optical area in the / id-v ^ diagram 45.

between the barite and lanthanum flint glasses from In no case should the optical glass ThO ₂

na = 1.67-1.74 and να = 42-48 are included in different ways.

like glass compositions become known. The decisive feature for the glasses in the front

Due to their different material composition ranges, theirs is extreme

However, settlement results in a highly variable optical 5 ° low tendency to crystallize. A glass that z. B.

and physical properties as well as extremely below 19.5% SiO ₂ , 13.1% B ₂ O ₃ , 1.6% Al ₂ O ₃ , 40.8%

Different smelting and processing properties - BaO, 5.1% CaO, 6.8% PbO, 11.0% La ₂ O ₃ , 1.8%

stocks. TiO ₂ and 0.3% As ₂ O _{3 is} composed

It is known that glasses with higher refractive indices, in addition to the extremely low nucleation, also achieve a maximum crystal growth rate of only a forming component, generally by reducing the glass's maximum crystal growth rate. Concurrent with this is 12.5 μπι / h. This low value is bound even by the much deeper-refractive barite gun, which is known to have an increase in the tendency to crystallize, unless stabilizing additives are added. Their growth rates are. _{The intermediate oxides Al 2} O ₃ , PbO, BeO and ZnO, which are at least twice up to 20 times higher, have mainly been used as such. 60 value higher. Quite apart from that, the glasses have these additives, however, on the above-mentioned lanthanum flint base in an even more extreme crioptic range, partly related to the refractive index lowering tendency with crystal growth oscillating or strongly increasing dispersion. With other speeds from 300 to 7000 | xm / h.
oxidic additives such as Li ₂ O, Na ₂ O, K ₂ O, MgO, BaO, due to the low tendency towards _{crystallization of CdO, La 2} O ₃ , Sb ₂ O ₃ , Bi ₂ O ₃ , ZrO _{2 , HfO 2} , ThO ₂ , open SnO _2, 65 glasses in accordance with the invention, all Mög-TiO _8, Ta ₂ O _5, Nb ₂ O ₅ and P ₂ O ₅ can corrections possibilities of melting and processing technology, are made on individual indices of refraction, however, in the following Tatelle In some applications it is not possible to adjust all dispersions. games of the glasses according to the invention indicated.

B ₈ O,

Al ₁ O ₁ BaO CaO

La ₁ O, TiO, WO, As ₁ O, η _Λ

19.5 13.1 1.6 40.8 5.1 21.8 12.7 1.6 39.6 5.0 19.6 13.5 2.0 40.8 5.5 18.9 15.6 1.6 39.6 5.0 20.0 13.5 1.6 42.1 5.3 20.1 13.5 1.6 39.0 5.3 19.5 13.0 1.8 40.8 5.3 18.9 12.7 1.6 42.5 5.0 20.1 10.4 1.6 42.1 5.3 19.6 13.0 1.5 40.8 5.0 18.9 12.7 1.6 39.6 5.0 19.9 13.3 - 41.4 5.3 18.9 12.7 4.6 39.6 4.9 19.0 12.5 1.3 39.4 5.7

6.8 11.0 1.8 - 0.3 1.69712 46.8 6.6 10.7 - 0.3 1.68720 47.2 5.5 11.0 1.8 - 0.3 1.68786 47.8 6.6 10.7 1.7 - 0.3 1.68859 47.5 7.0 8.3 1.9 - 0.3 1.68914 47.0 7.0 11.3 1.9 - 0.3 1.69016 46.9 6.5 11.0 1.8 - 0.3 1.69410 47.0 6.6 10.7 1.7 - 0.3 1.69621 46.3 7.0 11.3- 1.9 - 0.3 1.70058 45.5 5.5 10.5 1.8 2.0 0.3 1.70269 45.0 6.6 13.6 1.7 - 0.3 1.71130 43.3 6.9 11.1 1.8 - 0.3 1.69548 47.2 6.6 10.7 1.7 - 0.3 1.68653 46.7 5.0 10.6 1.2 5.0 0.3 1.70643 43.0

Claims (1)

“The other properties, such as the toughness, ϊ patent claims: chemical and crystallization behavior, are adversely affected. So it is of crucial importance 1. Optical glass of the system Interpretation of which components are used and RO RO PbO La O ^{5 m we} l ^cnem ratio these in the glass to one another biUg as 2 3 _{nen> um} ^ _6n meet the requirements of optical glass with a refractive index n _d = 1.68 to 1.72 and to become. an Abbe number v _d - 43 to 48, thereby It is therefore the object of the invention, for the otpi- characterized in that the melting rate see range from n _d = 1.68 to 1.72 and v _d = 43 to ic 48, for which only very little technically 18.9-22 percent by weight SiO ₂ , _{feare glasses} ^ are known, the melting of glasses 10-15.6 percent by weight B ₂ O ₃ , other than the system 39-43 percent by weight BaO, 8-14 weight percent La ₂ O ₃ , SiO ₂ -B ₂ O ₃ -BaO-PbO-La ₂ O ₃ 4-10 weight percent PbO, ^{3 2 3} 4 - 8 percent by weight CaO and to enable the required properties 1 - 5 percent by weight TiO ₂ optimally meet,