S-FPM4 is an optical glass for polishing lens and effective for secondary chromatic aberration correction in FPM Region.
08.20.2019
S-FPM4 has high partial dispersion ratios θg,F in the FPM region, and is an optical glass for polishing lenses that is effective for secondary chromatic aberration correction. A glass material that can be used in a wide range of applications, such as interchangeable and automotive lenses.
(Advantage)
High partial dispersion ratios θg,F
| S-FPM4 | ||
| Eco Optical Glass | ○ | |
| Refractive Index nd | 1.52841 | |
| Abbe Number νd | 76.46 | |
| Partial dispersion ratio θg,F | 0.5396 | |
| Abnormal dispersibility ⊿θg.F | 0.0218 | |
| CTE α (10-7/℃) |
-30～+70℃ | 123 |
| +100～+300℃ | 143 | |
| Transformation Point Tg(°C) | 488 | |
| Yield Point At(°C) | 520 | |
| Coloring | λ80 | 340 |
| λ5 | – | |
| Chemical Resistance | RW(P) | 1 |
| RA(P) | 3 | |
| W(S) | 1 | |
| SR | 51.3 | |
| PR | 4.3 | |
| Specific Gravity | 3.76 | |
| Knoop Hardness Hk | 360〔4〕 | |
| Abrasion Aa | 506 | |
| Detail Catalog DATA | ||
| Available shapes | •pressings •saw cut center-less ground cylindrical blanks •cut blanks |
|