In-House Production of Synthetic Infrared Glasses, with different optical properties
Chalcogenide Materials for NIR, SWIR, MWIR and LWIR Uses
US Manufacturing Capacity of 10 Metric Tons a Year. Suitable for Diamond Turning and Precision Molding
Overview
With a long history of experience in Chalcogenide Glass production, LightPath produces a variety of different Chalcogenide glasses in its Orlando, Florida facility.
All of LightPath’s Black Diamond™ Chalcogenide glasses are produced in boules of 120mm diameter, and can be further expanded using our proprietary molding technology, to larger diameters, as needed. Our Black Diamond™ materials are designed specifically to have the same refractive index whether diamond turned into lenses, conventionally polished, or molded into final form using our precision glass molding technology.
We produce our BD6 and BD2 glasses in quantities of up to 10 metric tons annually, and can further expand our production capacity. Like many other manufacturing processes at LightPath, most of our critical production equipment for these processes is either designed and built by LightPath engineering team, or by modifying existing commercial equipment. This allows us to achieve unique properties, such as materials that have the same refractive index whether molded or polished by Diamond Turning.
In November of 2021 LightPath received from the US Naval Research Laboratories (NRL) an exclusive usage license for additional Chalcogenide glasses developed by NRL’s scientists. LightPath is currently in the process of transitioning these materials into production. For more details, please contact us.
Properties
-3dB Transmission window |
SWIR (1-3μm) |
MWIR (3-5μm) |
LWIR (8-12μm) |
Physical Properties |
|||||||||||
Glass |
λ short (μm) |
λ long (μm) |
Index | dn/dT (ppm/°C) | V(1-3) | Index | dn/dT (ppm/°C) | V(3-5) | Index | dn/dT (ppm/°C) | V(8-12) | Density (g/cm3) | Tg (°C) | CTE (ppm/°C) | Thermal Power (1/°C) |
BDNL4 | 0.78 | 17.50 | 2.66 | -17.30 | 17 | 2.64 | -18.60 | 186 | 2.63 | -18.30 | 233 | 4.47 | 201 | 30.20 | -41.37 |
BDNL5 | 0.74 | 17.20 | 2.49 | 9.61 | 19 | 2.47 | 7.62 | 184 | 2.46 | 6.33 | 126 | 4.42 | 192 | 26 | -21.67 |
BDNL6 | 1.43 | 18.20 | 3.22 | 202 | 3.17 | 169 | 107 | 3.15 | 160 | 257 | 5.23 | 191 | 18.30 | 56.04 | |
BDNL7 | 0.57 | 12.70 | 2.40 | -4.38 | 24 | 2.38 | -7.34 | 159 | 2.357 | -8.11 | 47 | 3.17 | 201 | 25.30 | -31.27 |
BDNL8 | 0.79 | 18.90 | 2.68 | 2.97 | 16 | 2.66 | 1.20 | 184 | 2.64 | -0.40 | 186 | 4.51 | 193 | 25.70 | -25.94 |
BDNL9 | 0.61 | 12.80 | 2.43 | -3.64 | 23 | 2.41 | -3.83 | 160 | 2.38 | -5.94 | 51 | 3.28 | 197 | 25.10 | -29.37 |
BDNL10 | 0.74 | 17.50 | 2.54 | 27.20 | 18 | 2.52 | 22.60 | 191 | 2.51 | 21 | 135 | 4.44 | 191 | 27 | -13.10 |
BDNL16 | 0.74 | 13 | 2.59 | 21 | 18 | 2.57 | 14 | 157 | 2.55 | 12 | 78 | 3.89 | 182 | 24 | -16.29 |
BDNL103 | 2.73 | 65 | 16 | 2.71 | 61 | 170 | 2.70 | 58 | 167 | 4.54 | 314 | 14 | 20.10 | ||
BD6 | 0.83 | 17.50 | 2.81 | 14.10 | 2.79 | 169.20 | 2.781 | 30.50 | 159.40 | 4.63 | 185 | 22.50 | -5.38 | ||
BD2 | 0.93 | 16 | 2.63 | 2.621 | 173.70 | 2.60 | 61.10 | 109 | 4.66 | 285 | 14 | 24.13 |
Advantages
Chalcogenide Glasses (LightPath’s family of Black DiamondTM materials), are synthetically produced Amorphous materials, with advantages optical characteristics for use in the infrared spectrum.
Being amorphous materials, optics can be fabricated from them using precision glass molding techniques, allowing for significant cost savings in the fabrication process. Additionally, being synthetic materials, we can fine tune their properties, leading to different Thermo-Optic coefficient (dn/dT), changes in the dispersion curve, refractive indexes and more.
- The main advantages of Chalcogenides include:
- Full IR spectrum transmission
- High Refractive Index
- Soft but durable
- Lower density than Germanium (=Lighter weight)
- Not susceptible to thermal runaway
- Moldable – finished optics can be fabricated using precision glass molding
- Large diameter. Can be fabricated in different sizes