| CYTOP | PTFE | PFA | PMMA | Remarks | |
|---|---|---|---|---|---|
| Refraction index | 1.34 | 1.35 | 1.35 | 1.49 | Abbe’s refractometer |
| Light transmission ratio (%) | 95 | Translucent | Translucent | 93 | Visible light range, 200μm |
| Abbe’s number | 90 | − | − | 55 | Abbe’s number |
CYTOP Transmittance in the Near IR Region
CYTOP Transmittance in the Visible and UV Region
Internal transmittance (for 5 mm thickness)
| Wavelength (nm) | 250 | 400 | 550 | 850 | 1300 | 1550 | 1600 | 1700 | 1800 | 1900 | 2000 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Internal transmittance (%) |
100 | 100 | 100 | 100 | 100 | 100 | 100 | 99.9 | 99.85 | 99.75 | 99.15 |
Photo-elastic characteristics
| Sample | CYTOP | PC | PSt | PMMA | CR-39 | Optical glass | |
|---|---|---|---|---|---|---|---|
| Photo-elastic constant ×10-12Pa-1 | 6.5 | 76 | 8.5~10.3 | -2.8~−3.9 | 41 | 0.5~2.9 | |
| Photo-elastic sensitivity ×10-6m/N | 0.108 | 1.02 | 0.16 | 0.05 | 0.68 | − | |
| * Photo-elastic sensitivity α : | Number of interference fringes appeared when unit simple stress (or main stress difference) is applied to the unit thickness plate. | ||||||
Refractive Indices in the Near IR
| CYTOP | PMMA | Remarks | |
|---|---|---|---|
| Refractive index | 1.34 | 1.48 | Abbe’s refractometer (λ = 589 nm) |
| 1.3395 | 1.4878 | Prism coupler (λ = 633 nm) | |
| 1.3348 | 1.4792 | Prism coupler (λ = 1,300 nm) | |
| 1.3335 | 1.4778 | Prism coupler (λ = 1,550 nm) |
Refractive Indices in the short wavelength Region
| Wavelength (nm) |
Refractive index | Standard deviation |
| 238 | 1.35764 | 1.3×10-5 |
| 245 | 1.35637 | 1.2×10-5 |
| 275 | 1.35393 | 1.5×10-5 |
| 313 | 1.35132 | 1.7×10-5 |
| 365 | 1.34840 | 2.1×10-5 |
| 407 | 1.34566 | 2.0×10-5 |
| 436 | 1.34404 | 2.0×10-5 |
| 546 | 1.34020 | 3.3×10-5 |
| Measurement of refractive index |
| *Experimental method: A 60°prism with a mercury lamp as the source of white light was used to illuminate the sample at the minimum angle which refraction occurs. From this angle, the refractive index is calculated as follows; |
| n(λ)=sin((θm+ )/2)/sin(α/2) α is the vertical angle of the prism and θm is the angle of minimum deviation. |
| The results are showed in the table. The polymer wes CTL. |
Refractive index and Abbe’s number
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 · |
FEP Polymethacrylic acid trifluoroethyl Polymethacrylic acid isobutyl Polyacrylic acid methyl Diethylene glycol bisallyl Carbonate (CR-39) polymer Polymethacrylic acid methyl Poly α-bromoacrylic acid methyl Polymethacrylic acid 2,3-dibromopropyl Phthalic acid diallyl polymer Polymethacrylic acid phenyl Polybenzoic acid vinyl Polystyrene Polymethacrylic acid pentachlorophenyl Poly o-chlorostyrene Polyvinyl naphthalene Polyvinyl carbazole Diamond Other polymers including FK and PK Optical glass |
* Refractive index and Abbe’s number of
a typical organic polymer
