| OHARA | L-LAH81 |
806404 811401 |
||||||
| Refractive Index |  |
1.80610 | Abbe Number |  |
40.4 | Dispersion |  |
0.01995 |
| 1.806100 | 40.40 | 0.019953 | ||||||
 |
1.810840 |  |
40.15 |  |
0.020196 | |||
Refractive Indices |
||
 |
||
 |
2.32542 | 1.76087 |
 |
1.97009 | 1.76778 |
 |
1.52958 | 1.77540 |
 |
1.12864 | 1.78271 |
 |
1.01398 | 1.78533 |
 |
0.85211 | 1.79017 |
 |
0.76819 | 1.79363 |
 |
0.70652 | 1.79688 |
 |
0.65627 | 1.80018 |
 |
0.64385 | 1.80111 |
 |
0.6328 | 1.80199 |
 |
0.58929 | 1.80593 |
 |
0.58756 | 1.80610 |
 |
0.54607 | 1.81084 |
 |
0.48613 | 1.82013 |
 |
0.47999 | 1.82131 |
 |
0.44157 | 1.82998 |
 |
0.435835 | 1.83151 |
 |
0.404656 | 1.84125 |
 |
0.365015 | 1.85851 |
 |
0.334148 | |
 |
0.326106 | |
Thermal Properties |
||
| Strain Point (°C) |
StP |
526 |
| Annealing Point (°C) |
AP |
547 |
| Transformation Temperature (°C) |
Tg |
566 |
| Yield Point (°C) |
At |
602 |
| Softening Point (°C) |
SP |
645 |
| Expansion Coefficient   |
-30~+70°C |
58 |
+100~+300°C |
73 |
|
Thermal Conductivity |
k |
0.860 |
Mechanical Properties |
||
Young's Modulus |
E |
1127 |
| Rigidity Modulus |
G |
434 |
| Poisson's Ratio |  |
0.300 |
| Knoop Hardness | Hk |
640 [6] |
| Abrasion | Aa |
78 |
Photoelastic Constant |
 |
2.17 |
Partial Dispersions |
|
 |
0.014846 |
 |
0.006546 |
 |
0.005921 |
 |
0.010660 |
 |
0.025414 |
 |
0.011382 |
 |
0.009735 |
 |
0.026991 |
 |
0.015778 |
 |
0.009728 |
 |
0.010468 |
 |
0.037198 |
Deviation of Relative Partial Dispersions |
|
 |
0.0078 |
 |
0.0033 |
 |
-0.0071 |
 |
-0.0057 |
 |
-0.0340 |
Constants of Dispersion Formula |
||
326 ~ 1129 nm |
||
 |
1.89927344 | |
 |
2.70978866 |  |
 |
1.33163819 | |
 |
1.02901828 |  |
 |
4.24227173 | |
 |
1.00967566 |  |
1129 ~ 2325 nm |
||
|
||
|
||
|
||
|
||
|
||
|
||
Chemical Properties |
||
| Water Resistance (P) | RW(P) |
1 |
| Acid Resistance (P) | RA(P) |
3 |
| Weathering Resistance (S) | W(S) |
|
| Acid Resistance (S) | SR |
51.2 |
| Phosphate Resistance | PR |
1.2 |
| P = Powder Group, S = Surface Group | ||
Other Properties |
|||
| Bubble Quality Group | B |
||
| Specific Gravity | d |
4.53 |
|
| Coloring |  |
41 |
|
 |
34 |
||
Relative Partial Dispersions |
|
 |
0.7440 |
 |
0.3281 |
 |
0.2967 |
 |
0.5343 |
 |
1.2737 |
 |
0.5704 |
 |
0.4879 |
 |
1.3527 |
 |
0.7812 |
 |
0.4817 |
 |
0.5183 |
 |
1.8418 |
Internal Transmittance |
||
 |
 |
 |
280 |
||
290 |
||
300 |
||
310 |
||
320 |
||
330 |
||
340 |
0.090 |
|
350 |
0.370 |
|
360 |
0.650 |
|
365 |
||
370 |
0.810 |
|
380 |
0.890 |
|
390 |
0.932 |
|
400 |
0.954 |
|
420 |
0.974 |
|
440 |
0.982 |
|
460 |
0.987 |
|
480 |
0.991 |
|
500 |
0.994 |
|
550 |
0.997 |
|
600 |
0.997 |
|
650 |
0.998 |
|
700 |
0.998 |
|
800 |
0.999 |
|
900 |
0.999 |
|
1000 |
0.999 |
|
1200 |
0.998 |
|
1400 |
0.995 |
|
1600 |
0.993 |
|
1800 |
0.985 |
|
2000 |
0.966 |
|
2200 |
0.910 |
|
2400 |
0.720 |
|
Temperature Coefficients of Refractive Index |
||||||||
Range of Temperature (°C) |
dn / dt relative  |
|||||||
t |
C' |
He-Ne |
D |
e |
F' |
g |
i |
|
| -40 ~ -20 | 6.7 |
7.5 |
7.6 |
7.8 |
8.2 |
9.0 |
9.8 |
|
| -20 ~ 0 | 6.8 |
7.7 |
7.7 |
8.0 |
8.3 |
9.2 |
10.1 |
|
| 0 ~ 20 | 6.8 |
7.7 |
7.8 |
8.1 |
8.4 |
9.3 |
10.2 |
|
| 20 ~ 40 | 6.8 |
7.8 |
7.8 |
8.1 |
8.5 |
9.4 |
10.4 |
|
| 40 ~ 60 | 6.9 |
7.9 |
8.0 |
8.3 |
8.7 |
9.6 |
10.6 |
|
| 60 ~ 80 | 7.1 |
8.1 |
8.2 |
8.5 |
8.9 |
9.9 |
10.9 |
|