Smart Glass primarily utilises two technology families: PDLC (Polymer Dispersed Liquid Crystal) and PNLC (Polymer Network Liquid Crystal). In both cases, a wafer-thin film lies between two panes of glass, in which liquid crystals align themselves when electrical voltage is applied, allowing light to pass through refraction-free — the pane becomes clear. Without voltage, the crystals scatter the light — the pane appears milky-opaque (≈ 85–95% scatter).
PDLC is the older, established technology. It requires a constant voltage (typically 48–65 V AC) in the transparent state, is robust, widely available, and ranges in acquisition cost between €600 and €1,200 per square metre of glass surface.
PNLC is the newer variant with significantly lower energy consumption (≈ 0.5–1 W/m²), faster switching times (<100 ms instead of 200–500 ms), higher clarity in the transparent state, and a longer service life. It costs approximately 20–40% more than PDLC.
Smart Glass is primarily used where privacy and transparency must alternate dynamically: boardrooms (dimming for presentations), showrooms (privacy during consultations), hospitals (privacy for patient rooms), hotels (bathroom-to-room separation), and architectural facades. Optionally, Smart Glass can also serve as a rear projection surface in its opaque state — a very clean alternative to traditional projection screens.