High Speed Patterning for Smart Window Manufacturing

Our TOPAZ G is a tailor-made system for layer-side structuring of TCO electrodes on Smart Windows with high throughput and very high resolution.

Managing a tight focus

First of all, it is important to mention that the Smart Window glass pane to be laser structured has a length of more than 3 m, but its thickness is only about 1 mm. An even greater challenge to the patterning process is the fact that the structure width to be produced is sometimes less than 10 µm, with a total tolerance of less than 2 µm over this large glass pane. This is the only way to ensure that the pattern is invisible to the human eye. As a result of this structure width, the theoretical depth of focus of the laser beam at a spot size of 10 µm (1/e²) is less than 150 µm.

To meet these challenges, the glass pane is fixed on a large, flat granite table. In addition, the topology of the granite table is determined and the focus of each patterning head is adjusted accordingly during patterning.

This ensures long-term stable structuring conditions for a sustainable quality of the final product. Remember, the final product is a window and the human eye is not easily fooled.

The Heart of the TOPAZ G

Two aspects accomplish the required throughput of the TOPAZ G, one is parallelization, the other one is scanning on-the-fly. Parallel scanning is accomplished with of 5 single patterning heads. All of them extremely well calibrated in their own working area as well as with regard to each other and the linear axis system. Scanning on-the-fly means the laser beam is deflected at high speed by a 2D scanner while the axis system moves the patterning head. This mode of operation achieves an unmatched throughput compared to standard step-and-repeat approaches. 

Accuracy and throughput at the next level for a scalable and economical smart window production. The TOPAZ G – a benchmark for large area patterning.


Thin-filmstransparent conductive oxides (e.g. ITO, FTO and othes), active layers
Patterning resolution<  10 µm 
Processing ablative patterning from the film side
Scanning on-the-flyYes, based on up to 5 parallel scanning heads
Substrate dimensions1.500 x 3.050 mm²
glass thicknessaround 1 mm 
Working area (x, y)Identical to substrate dimensions
Axis speedup to 500 mm/s 
Position Accuracy 
within temperature range 22 ± 2C°
+/- 15 µm
Particle extraction yes
MES interfaceyes
Footprint 3.000 m x 4.700 m
Weightapprox. 14 t
Loading and unloadingautomatic


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