| OHARA | BSL7Y |
516643 518641 |
||||||
| Refractive Index |  |
1.51633 | Abbe Number |  |
64.3 | Dispersion |  |
0.00803 |
| 1.516330 | 64.24 | 0.008037 | ||||||
 |
1.518248 |  |
64.04 |  |
0.008092 | |||
Refractive Indices |
||
 |
||
 |
2.32542 | 1.48829 |
 |
1.97009 | 1.49417 |
 |
1.52958 | 1.50028 |
 |
1.12864 | 1.50528 |
 |
1.01398 | 1.50681 |
 |
0.85211 | 1.50933 |
 |
0.76819 | 1.51096 |
 |
0.70652 | 1.51242 |
 |
0.65627 | 1.51386 |
 |
0.64385 | 1.51425 |
 |
0.6328 | 1.51462 |
 |
0.58929 | 1.51626 |
 |
0.58756 | 1.51633 |
 |
0.54607 | 1.51825 |
 |
0.48613 | 1.52189 |
 |
0.47999 | 1.52234 |
 |
0.44157 | 1.52562 |
 |
0.435835 | 1.52619 |
 |
0.404656 | 1.52973 |
 |
0.365015 | 1.53574 |
 |
0.334148 | 1.54218 |
 |
0.326106 | 1.54422 |
Thermal Properties |
||
| Strain Point (°C) |
StP |
527 |
| Annealing Point (°C) |
AP |
559 |
| Transformation Temperature (°C) |
Tg |
577 |
| Yield Point (°C) |
At |
616 |
| Softening Point (°C) |
SP |
714 |
| Expansion Coefficient   |
-30~+70°C |
68 |
+100~+300°C |
81 |
|
Thermal Conductivity |
k |
1.182 |
Mechanical Properties |
||
Young's Modulus |
E |
811 |
| Rigidity Modulus |
G |
336 |
| Poisson's Ratio |  |
0.207 |
| Knoop Hardness | Hk |
570 [6] |
| Abrasion | Aa |
87 |
Photoelastic Constant |
 |
|
Partial Dispersions |
|
 |
0.007046 |
 |
0.002891 |
 |
0.002475 |
 |
0.004393 |
 |
0.009857 |
 |
0.004295 |
 |
0.003543 |
 |
0.009552 |
 |
0.007443 |
 |
0.003996 |
 |
0.004096 |
 |
0.013395 |
Deviation of Relative Partial Dispersions |
|
 |
0.0286 |
 |
0.0059 |
 |
-0.0048 |
 |
-0.0031 |
 |
0.0014 |
Constants of Dispersion Formula |
||
326 ~ 1129 nm |
||
 |
1.13329383 | |
 |
1.36897201 |  |
 |
7.03456004 | |
 |
6.69407868 |  |
 |
2.37391760 |  |
 |
7.07030316 |  |
1129 ~ 2325 nm |
||
|
1.01218580 | |
|
2.58122629 | |
|
1.13916089 | |
|
5.66358122 | |
|
1.96285352 | |
|
1.12904303 |  |
Chemical Properties |
||
| Water Resistance (P) | RW(P) |
2 |
| Acid Resistance (P) | RA(P) |
2 |
| Weathering Resistance (S) | W(S) |
1 |
| Acid Resistance (S) | SR |
1.0 |
| Phosphate Resistance | PR |
1.0 |
| P = Powder Group, S = Surface Group | ||
Other Properties |
|||
| Bubble Quality Group | B |
1 |
|
| Specific Gravity | d |
2.50 |
|
| Coloring |  |
32 |
|
 |
29 |
||
Relative Partial Dispersions |
|
 |
0.8767 |
 |
0.3597 |
 |
0.3080 |
 |
0.5466 |
 |
1.2265 |
 |
0.5344 |
 |
0.4408 |
 |
1.1885 |
 |
0.9198 |
 |
0.4938 |
 |
0.5062 |
 |
1.6553 |
Internal Transmittance |
||
 |
 |
 |
280 |
||
290 |
0.060 |
|
300 |
0.430 |
0.120 |
310 |
0.780 |
0.540 |
320 |
0.932 |
0.830 |
330 |
0.978 |
0.945 |
340 |
0.991 |
0.978 |
350 |
0.996 |
0.990 |
360 |
0.997 |
0.992 |
365 |
0.998 |
0.995 |
370 |
0.998 |
0.996 |
380 |
0.998 |
0.996 |
390 |
0.999 |
0.997 |
400 |
0.999 |
0.998 |
420 |
0.999 |
0.998 |
440 |
0.999 |
0.998 |
460 |
0.999 |
0.998 |
480 |
0.999 |
0.998 |
500 |
0.999 |
0.999 |
550 |
0.999 |
0.999 |
600 |
0.999 |
0.998 |
650 |
0.999 |
0.998 |
700 |
0.999 |
0.999 |
800 |
0.999 |
0.999 |
900 |
0.999 |
0.997 |
1000 |
0.997 |
0.993 |
1200 |
0.997 |
0.993 |
1400 |
0.969 |
0.924 |
1600 |
0.990 |
0.975 |
1800 |
0.981 |
0.952 |
2000 |
0.962 |
0.908 |
2200 |
0.860 |
0.680 |
2400 |
0.800 |
0.580 |
Temperature Coefficients of Refractive Index |
||||||||
Range of Temperature (°C) |
dn / dt relative  |
|||||||
t |
C' |
He-Ne |
D |
e |
F' |
g |
i |
|
| -40 ~ -20 | 2.3 |
2.6 |
2.6 |
2.7 |
2.8 |
3.0 |
3.2 |
3.8 |
| -20 ~ 0 | 2.4 |
2.7 |
2.7 |
2.8 |
2.9 |
3.2 |
3.4 |
4.0 |
| 0 ~ 20 | 2.5 |
2.8 |
2.9 |
3.0 |
3.1 |
3.3 |
3.6 |
4.2 |
| 20 ~ 40 | 2.6 |
3.0 |
3.0 |
3.1 |
3.2 |
3.5 |
3.7 |
4.4 |
| 40 ~ 60 | 2.8 |
3.1 |
3.1 |
3.2 |
3.3 |
3.6 |
3.9 |
4.6 |
| 60 ~ 80 | 2.9 |
3.2 |
3.2 |
3.3 |
3.4 |
3.7 |
4.0 |
4.8 |