Germanium (Ge) is a high-value material widely used in infrared (IR) optics, night vision systems, thermal imaging, and scientific instruments. While germanium’s excellent infrared transmission and mechanical properties make it ideal for lenses, its crystalline brittleness makes cutting and processing extremely challenging.
This article explains how endless diamond wire saws enable precision cutting of germanium lenses while minimizing surface damage and maximizing material yield.
Material Characteristics of Germanium
- High refractive index (n ≈ 4.0 in IR)
- Excellent infrared transmission (2–14 μm)
- Relatively soft (Mohs ~6) but brittle
- High density and low thermal conductivity
These features create unique machining challenges:
- Edge chipping and microcracks are common with mechanical saws
- Heat generation can distort or damage lens surfaces
- Fine surface finish is critical to avoid post-polishing loss
Why Use Diamond Wire Saw for Germanium Lens Cutting?
The endless diamond wire saw offers key advantages:
- Minimal kerf loss (as low as 0.35 mm using 0.3 mm wire)
- Cold cutting process with no heat-affected zone
- Smooth surface finish with roughness <3 μm
- Highly controllable feed and wire speed to reduce stress
- Ideal for both raw blank slicing and complex contour cut
Germanium Cutting Application Case
One of our customers needed to cut a special arc-shaped geometry from a single-crystal germanium block. After multiple rounds of testing, our SGI20 model demonstrated exceptional cutting accuracy and contour control. The customer was highly satisfied with the results and proceeded to place three separate orders for multiple units to expand their precision optics production line.
[Real case video Germanium Arc Cutting with SGI20 Diamond Wire Saw]
Recommended Equipment Models
Depending on production scale and complexity, Vimfun offers several ideal machines:
- SG20: Entry-level CNC model for clean slicing of small-diameter Ge lenses
- SGI 20: 4-axis version for angled or prism-shape Ge optics
All systems support precise control over tension, speed, slicing path, and coolant use.
Germanium is a cornerstone material in the infrared optics industry, but its brittleness demands a highly controlled, non-invasive cutting process. Endless diamond wire saws provide the optimal combination of precision, minimal thermal effect, and high surface integrity.
Looking for the right tool to slice your Ge optics?
Contact Vimfun to configure the most suitable diamond wire cutting system for your material and production needs.