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Window film technology

Cesium Tungsten Oxide (CWO)

Cesium tungsten oxide (CWO) is a nano-particle used in some premium ceramic window films to absorb near-infrared while transmitting visible light, one of the chemistries behind very high solar heat rejection.

CWO nano-particles selectively absorb wavelengths in the 800–1500 nm band, which is exactly where most solar heat lives. Films built around CWO can achieve very high solar heat rejection at high VLT without using metals.

The chemistry is dielectric, so CWO-based films are signal-friendly — no ERP, GPS or CarPlay attenuation. Premium nano-ceramic products in Singapore, including some Platinum99 variants, use CWO as part of the active rejection layer.

For comparison: a CWO-enhanced ceramic at 70% VLT can match a metallised film at 50% VLT on total solar energy rejection, but without the signal trade-offs.