D-FK61A by CDGM

Preferred Very Common Precision Molding Environmentally Friendly

D-FK61A by CDGM is a preferred optical glass with a very common melt frequency. It transmits from 0.29 to 2.40 µm with an nd of 1.497 and a Vd of 81.605419. It has high thermal expansion (CTE of 12.6×10⁻⁶/K), excellent chemical resistance, high relative cost, and precision molding compatibility.

Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 0.302–2.325 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 0.302–2.325 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 0.290–2.400 µm
Optical Properties
Refractive Index (nd) 1.497
Abbe Number (Vd) 81.605419
Dispersion Formula Sellmeier
Wavelength Range 0.302 — 2.325 µm
$$n(\lambda) = \sqrt{1 + \frac{0.714812\,\lambda^2}{\lambda^2 - 0.0108371} + \frac{0.502985\,\lambda^2}{\lambda^2 - 0.00132156} + \frac{0.83612\,\lambda^2}{\lambda^2 - 153.361}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 12.6
TCE 100/300°C (10-6/K) 15.5
Thermal Conductivity (W/mK) —
Heat Capacity (J/gK) —
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-1.94 \times 10^{-5} + 2(2.54 \times 10^{-9})\,\Delta T + 3(-2.83 \times 10^{-11})\,\Delta T^2 + \frac{3.05 \times 10^{-7} + 2(-9.31 \times 10^{-11})\,\Delta T}{\lambda - 0.242}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$
Physical Properties
Density (g/cm³) 3.68
Relative Cost 14.0
Mechanical Properties
Young's Modulus (GPa) 73.67
Poisson's Ratio 0.297
Knoop Hardness (kgf/mm²) 360.0
Chemical Resistance
Climatic Resistance 1
Stain Resistance —
Acid Resistance —
Alkali Resistance —
Phosphate Resistance —
Notes

anneal rate:4℃/h

Similar Glasses (Other Manufacturers)
Glass Manufacturer nd Vd Compare
N-PK52A Schott 1.497 81.61
FCD1 Hoya 1.497 81.61
FPL51 Ohara 1.496999 81.61466
N-PK52 Schott 1.497005 81.633263
M-FCD1 Hoya 1.4971 81.56
FCD1B Hoya 1.4971 81.56
S-FPL51 Ohara 1.496999 81.545888
MC-FCD1-M20 Hoya 1.4969 81.51
MP-FCD1-M20 Hoya 1.4969 81.51
K-PFK80 Sumita 1.497 81.5
Similar Glasses (CDGM)
Glass Manufacturer nd Vd Compare
H-FK61B CDGM 1.497 81.605419
D-FK61 CDGM 1.497 81.611615
H-FK61 CDGM 1.497 81.612838
H-FK61GTI CDGM 1.497 81.612838
D-FK61A-25 CDGM 1.49665 81.549116
D-FK61-25 CDGM 1.49653 81.531772
H-FK55 CDGM 1.5502 75.224681
H-FK71 CDGM 1.4565 90.273821
H-FK71A CDGM 1.456498 90.470884
D-QK3L CDGM 1.48749 70.440487
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