Phosphate glass useful in high energy lasers

• US 5,173,456 A
• Filed: 12/20/1990
• Issued: 12/22/1992
• Est. Priority Date: 12/20/1990
• Status: Expired due to Fees

• Current Assignee: Schott Glass Technologies, Inc.
• Original Assignee: Schott Glass Technologies, Inc.
• Inventors: Guesto-Barnak, Donna, Hayden, Yuiko T.
• Primary Examiner(s): Dixon, Jr., William R.
• Assistant Examiner(s): MARCHESCHI, MICHAEL A
• Application Number:
  US07/630,610
• Time in Patent Office: 733 Days
• Field of Search: 252/301.4 P, 252/301.6 P, 501/37, 501/45, 501/47, 501/48, 501/73, 501/78, 501/77, 501/152
• US Class Current: 501/45
• CPC Class Codes: C03C 3/16 containing phosphorus
• CPC Class Codes: C03C 3/17 containing aluminium or beryllium
• CPC Class Codes: C03C 3/19 containing boron
• CPC Class Codes: C03C 4/0071 for laserable glass

Abstract

A low-or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀° C. >0.85 W/mK, a low coefficient of thermal expansion, α₂₀°-300° C. <80×10^-7 /°C., low emission cross section, σ<2.5×10^-20 cm², and a high fluorescence lifetime, τ>325 μsecs at 3 wt. % Nd doping, consisting essentially of (on an oxide composition basis):

______________________________________                                    

Mole % ______________________________________ P₂ O₅ 52-72 Al₂ O₃ 0-<20 B₂ O₃ >0-25 ZnO 0-31 Li₂ O 0-5 K₂ O 0-5 Na₂ O 0-5 Cs₂ O 0-5 Rb₂ O 0-5 MgO >0-<30 CaO 0-20 BaO 0-20 SrO 0-<20 Sb₂ O₃ 0-<1 As₂ O₃ 0-<1 Nb₂ O₅ 0-<1 Ln₂ O₃ up to 6.5 PbO 0-<5 SiO₂ 0-3 ______________________________________

wherein

Ln₂ O₃ is the sum of lanthanide oxides;

ΣR₂ O is <5, R being Li, Na, K, Cs, and Rb; the sum of Al₂ O₃ and MgO is <24 unless ΣR₂ O is 0, then the sum of Al₂ O₃ and MgO is <42; and the ratio of MgO to B₂ O₃ is 0.48-4.20.

Claims

1. A low- or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀°

C. >

0.85 W/mK, a low coefficient of thermal expansion, α

₂₀°

-300°

C. <

80×

10^-7 /°

C., low emission cross section, α

<

2.5×

10^-20 cm², and a high fluorescence lifetime, τ

>

325 μ

secs at 3 wt. % Nd (or equivalent) doping, consisting essentially of (on an oxide composition basis);

space="preserve" listing-type="tabular">______________________________________ Mole % ______________________________________ P.sub.2 O.sub.5 52-72 Al.sub.2 O.sub.3 0-<

20 B.sub.2 O.sub.3 >

0-25 ZnO 0-31 Li.sub.2 O 0-5 K.sub.2 O 0-5 Na.sub.2 O 0-5 Cs.sub.2 O 0-5 Rb.sub.2 O 0-5 MgO >

0-<

30 CaO 0-20 BaO 0-20 SrO 0-<

20 Sb.sub.2 O.sub.3 0-<

1 As.sub.2 O.sub.3 0-<

1 Nb.sub.2 O.sub.5 0-<

1 Ln.sub.2 O.sub.3 up to 6.5 PbO 0-<

5 SiO.sub.2 0-3 ______________________________________

wherein

Ln₂ O₃ is the sum of lanthanide oxides;

R being Li, Na, K, Cs, and Rb; and

said glass substantially corresponds to a point within the upper lined portion of FIG. 1C.

15. A glass according to claim 1, wherein the ratio of P₂ O>

to Al₂ O₃ is 3.5-7.5.

26. A glass according to claim 1, wherein Ln₂ O₃ includes Nd₂ O₃ as a lasing species.

28. A glass according to claim 1, wherein said glass composition further contains 0.1-1.5 wt. % antisolarants.

30. A glass according to claim 1, wherein the SiO₂ content is zero.

2. A low- or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀°

C. >

0.85 W/mK, a low coefficient of thermal expansion, α

₂₀°

-300°

C. <

80×

10^-7 /°

C., low emission cross section, σ

<

2.5×

10^-20 cm², and a high fluorescence lifetime, τ

>

325 μ

secs at 3 wt. % Nd doping, consisting essentially of (on an oxide composition basis);

space="preserve" listing-type="tabular">______________________________________ Mole % ______________________________________ P.sub.2 O.sub.5 52-72 Al.sub.2 O.sub.3 0-<

20 B.sub.2 O.sub.3 >

0-25 ZnO 0-31 Li.sub.2 O 0-5 K.sub.2 O 0-5 Na.sub.2 O 0-5 Cs.sub.2 O 0-5 Rb.sub.2 O 0-5 MgO >

0-<

30 CaO 0-20 BaO 0-20 SrO 0-<

20 Sb.sub.2 O.sub.3 0-<

1 As.sub.2 O.sub.3 0-<

1 Nb.sub.2 O.sub.5 0-<

1 Ln.sub.2 O.sub.3 up to 6.5 PbO 0-<

5 SiO.sub.2 0-3 ______________________________________

Ln₂ O₃ is the sum of lanthanide oxides;

R being Li, Na, K, Cs, and Rb;

the sum of Al₂ O₃ and MgO is <

24 unless Σ

R₂ O is 0, then the sum of Al₂ O₃ and MgO is <

42; and

the ratio of MgO to B₂ O₃ is 0.48-4.20.

3. A glass according to claim 2, wherein, R¹ being Ba, Mg, Ca, Sr, Pb and Zn if P₂ O₅ is ≧

60 and Σ

R₂ O is 0, then the sum of Al₂ O₃, B₂ O₃, and R¹ O is <

30.4,.

4. A glass according to claim 2, wherein the sum of Al₂ O₃ and MgO is >

9.1.

5. A glass according to claim 2, wherein the sum of MgO and ZnO is 0.0-48.

6. A glass according to claim 2, wherein the sum of Al₂ O₃, MgO, and ZnO is >

14.3 and <

46.2.

7. A glass according to claim 2, wherein the sum of P₂ O₅, Al₂ O₃, B₂ O₃, MgO, and ZnO is ≧

88.

8. A glass according to claim 2, wherein the sum of Al₂ O₃, B₂ O₃, and MgO is >

10.5 and <

46.2.

9. A glass according to claim 2, wherein Σ

R₂ O is 0.0.

10. A glass according to claim 2, wherein R⁴ being Ba, Mg, Ca, Sr, Pb and Zn, and R² being Al, B and Ln of R¹ O and R²₂ O₃ is >

28.8 and <

46.2.

11. A glass according to claim 2, wherein the sum of Al₂ O₃ and B₂ O₃ is >

9.1 and <

30.5.

12. A glass according to claim 2, wherein the sum of Al₂ O₃, B₂ O₃, and ZnO is >

10.5 and <

41.2.

13. A glass according to claim 2, wherein the amount of Al₂ O₃ is 4-<

20.

14. A glass according to claim 2, wherein Σ

R₂² O₃ is 10-40 and R² is Al, B and Ln.

16. A glass according to claim 2, wherein α

₂₀°

-300°

C. is <

75×

10^-6 /°

C.

17. A glass according to claim 2, wherein the index of refraction, n_d, is <

1.530.

18. A glass according to claim 2, wherein the index of refraction, n_d, is <

1.510.

19. A glass according to claim 2, wherein the nonlinear index, n₂, is <

1.10.

20. A glass according to claim 2, wherein the effective linewidth, Δ

λ

eff, is about 27.0-30.5 nm.

22. A glass according to claim 16, wherein if P₂ O₅ is ≧

60 and Σ

R₂ O is 0, then the sum of Al₂ O₃, B₂ O₃, and R¹ O is <

30.4, R¹ being Ba, Mg, Ca, Sr, Pb and Zn.

25. A glass according to claim 2, wherein the ratio of MgO to B₂ O₃ is 0.48-4.20.

27. A glass according to claim 2, wherein Ln₂ O₃ includes Nd₂ O₃ as a lasing species.

29. A glass according to claim 2, wherein said glass composition further contains 0.1-1.5 wt. % antisolarants.

31. A glass according to claim 2, wherein the SiO₂ content is zero.

21. A low- or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀°

C. >

0.85 W/mK, a low coefficient of thermal expansion, α

₂₀°

-300°

C. <

80×

10^-7 /°

C., low emission cross section, σ

<

2.5×

10^-20 cm², and a high fluorescence lifetime, τ

>

325 μ

secs at 3 wt. % Nd doping, consisting essentially of (on an oxide composition basis);

space="preserve" listing-type="tabular">______________________________________ Mole % ______________________________________ P.sub.2 O.sub.5 52-72 Al.sub.2 O.sub.3 0-<

20 B.sub.2 O.sub.3 >

0-25 ZnO 0-31 Li.sub.2 O 0-5 K.sub.2 O 0-5 Na.sub.2 O 0-5 Cs.sub.2 O 0-5 Rb.sub.2 O 0-5 MgO >

0-<

30 CaO 0-20 BaO 0-20 SrO 0-<

20 Sb.sub.2 O.sub.3 0-<

1 As.sub.2 O.sub.3 0-<

1 Nb.sub.2 O.sub.5 0-<

1 Ln.sub.2 O.sub.3 up to 6.5 PbO 0-<

5 SiO.sub.2 0-3 ______________________________________

wherein

Ln₂ O₃ is the sum of lanthanide oxides;

R being Li, Na, K, Cs, and Rb;

if Σ

R₂ O is >

0, then the sum of MgO and ZnO is ≦

10; and

the ratio of MgO to B₂ O₃ is 0.48-4.20.

32. A glass according to claim 21, wherein the SiO₂ content is zero.

23. A low- or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀°

C. >

0.85 W/mK, a low coefficient of thermal expansion, α

₂₀°

-300°

C. <

80×

10^-7 /°

C., low emission cross section, σ

<

2.5×

10^-20 cm², and a high fluorescence lifetime, τ

>

325 μ

secs at 3 wt. % Nd doping, consisting essentially of (on an oxide composition basis);

space="preserve" listing-type="tabular">______________________________________ Mole % ______________________________________ P.sub.2 O.sub.5 52-72 Al.sub.2 O.sub.3 0-<

20 B.sub.2 O.sub.3 5-25 ZnO 0-31 Li.sub.2 O 0-5 K.sub.2 O 0-5 Na.sub.2 O 0-5 Cs.sub.2 O 0-5 Rb.sub.2 O 0-5 MgO >

0-<

30 CaO 0-20 BaO 0-20 SrO 0-<

20 Sb.sub.2 O.sub.3 0-<

1 As.sub.2 O.sub.3 0-<

1 Nb.sub.2 O.sub.5 0-<

1 Ln.sub.2 O.sub.3 up to 6.5 PbO 0-<

5 SiO.sub.2 0-3 ______________________________________

wherein

Ln₂ O₃ is the sum of lanthanide oxides;

Σ

R₂ O is <

5, R being Li, Na, K, Cs, and Rb;

the sum of Al₂ O₃ and MgO is <

24 unless Σ

R₂ O is 0, then the sum of Al₂ O₃ and MgO is <

42; and

the ratio of MgO to B₂ O₃ is 0.48-4.20.

33. A glass according to claim 23, wherein the SiO₂ content is zero.

24. A low- or no-silica, low- or no-alkali phosphate glass useful as a laser amplifier in a multiple pass, high energy laser system having a high thermal conductivity, K₉₀°

C. >

0.85 W/mK, a low coefficient of thermal expansion, α

₂₀°

-300°

C. <

80×

10^-7 /°

C., low emission cross section, σ

<

2.5×

10^-20 cm², and a high fluorescence lifetime, τ

>

325 μ

secs at 3 wt. % Nd doping, consisting essentially of (on an oxide composition basis);

space="preserve" listing-type="tabular">______________________________________ Mole % ______________________________________ P.sub.2 O.sub.5 52-72 Al.sub.2 O.sub.3 0-<

20 B.sub.2 O.sub.3 >

0-25 ZnO 5-31 Li.sub.2 O 0-5 K.sub.2 O 0-5 Na.sub.2 O 0-5 Cs.sub.2 O 0-5 Rb.sub.2 O >

0-5 ε

R.sub.2 O <

5 MgO >

0-<

30 CaO 0-20 BaO 0-20 SrO 0-<

20 Sb.sub.2 O.sub.3 0-<

1 As.sub.2 O.sub.3 0-<

1 Nb.sub.2 O.sub.5 0-<

1 Ln.sub.2 O.sub.3 up to 6.5 PbO 0-<

5 SiO.sub.2 0-3 ______________________________________

wherein

Ln₂ O₃ is the sum of lanthanide oxides;

R being Li, Na, K, Cs, and Rb;

the sum of Al₂ O₃ and MgO is <

24 unless Σ

R₂ O is 0, then the sum of Al₂ O₃ and MgO is <

42; and

.

the ratio of MgO to B₂ O₃ is 0.48-4.20.

34. A glass according to claim 24, wherein the SiO₂ content is zero.