Glass Preform

The Optical Fibre market is booming and the growth can be attributed to the growing popularity of high-bandwidth internet connections, opportunities in healthcare industry, and investments in telecommunication infrastructure, among other factors. Changing customer needs of Low Latency and edge computing is leading to the need of optical fibre network densification globally.

The Data Boom has led to the emergence of Optical Fibre manufactures and the basic raw material for them is the Glass Preform. So the requirement of Glass Preform is going to increase exponentially in line with the Fibre requirement. Major hurdles faced by a new player is High Capex involved, unique technical expertise and High process in-efficiencies. We can address most of these problems with our product.

We are one the leading manufacturer of single mode Glass Preforms in the world. We are unique in the sense that we start with Silicone Metal and end up with the high quality “Glass Preforms”.

The Glass Preforms are made of very high purity (5N) chemicals which results into the best quality of Optical Fibre.

These preforms are used to make optical fibers, which can potentially transmit data at high speed. Optical fibers are flexible transparent fiber cables made up of high-quality glass, plastic, and silica that operate on the principle of total internal reflection of light.

Core Competencies of STL are

  • Best Quality Glass: The glass assures best yields with maximum uptime and efficiencies
  • Technical Expertise: Partners can leverage STL’s 20+ years of experience in Glass Manufacturing Technology
  • Customized Preform Sizes: We can provide customizable preforms sizes (Length*Diameter), customized to best suit the user requirement
  • Use Case oriented: Preforms suited to different types of Optical Fibre (Low Attenuation/Bend Insensitive) as per the use case

Sample Specification



Composition and Dimensions
Effective Length*: 1450 ± 150 mm
Average diameter D(mm)*: 130 ± 10
Diameter Variation within preform (mm) : ≤8
Cone/Taper Length (mm): ≤160
Bow (mm/m) : ≤2.0

Target Fibre Parameters
Cladding Diameter : 125 ± 1 µm
Attenuation at 1310 nm: ≤ 0.34 dB/km
Attenuation at 1383 nm (Initial value): ≤0.34 dB/km
Attenuation at 1625 nm : ≤0.24 dB/km
Uniformity of Attenuation:≤ 0.10 dB at 1310nm (Discontinuity in OTDR trace)
Slope at Zero dispersion wavelength: ≤0.092 ps/nm2. km
Core Concentricity Error: ≤0.6 µm
Cladding Non –circularity: ≤1.0 %
Polarized Mode Dispersion (PMD): ≤0.2ps/√km
Bend loss 1 turn 20mm Diameter 1550 nm:≤0.75 dB
Bend loss 10 turn 30mm Diameter 1550 nm:≤0.25 dB
Bend loss 10 turn 30mm Diameter 1625 nm: ≤1.0 dB
*Customizable dimensions