Electric privacy film: how PDLC technology works
Electric privacy film — often called PDLC or smart film — turns ordinary glazing into a wall whose transparency you control. Here is what it actually does, and what it does not.
The principle: liquid crystals between conductive layers
PDLC stands for Polymer Dispersed Liquid Crystal. The film holds liquid crystals suspended between two transparent conductive layers. With no current, the crystals sit in random directions: they scatter light in every direction, and the glazing takes on a milky white appearance that blocks the view.
As soon as current is applied, the crystals align along the same axis. Light then passes through without being scattered, and the glazing becomes clear again. The change is near-instant and can be repeated indefinitely.
Retrofit on existing glazing: what it changes
The adhesive film is applied to glass already in place, which avoids replacing a partition or a window frame. That is the major difference with laminated smart glass, which requires changing the whole unit.
Not every pane is compatible, though. Surface condition, glass type, existing coatings and access to the inner face all shape the result. That is why a survey always precedes the quote.
- Interior or exterior glazing depending on the configuration
- Smooth, clean surface accessible from inside
- Cable routing and transformer position to plan ahead
- Film cut to the exact dimensions of each pane
Control options
Three families cover nearly every project: the wall switch, the radio remote, and app-based control from a smartphone. Integration with an existing building-automation system is possible, but assessed case by case against the equipment in place.
The limits, stated plainly
Privacy film delivers visual privacy, not blackout. Light still passes through in the private state: it is not a blackout blind, and it is not a darkening solution for a projection room.
In strong backlight, a silhouette very close to the glass may remain partly perceptible. Finally, if the power fails, the film returns to its private state: privacy is preserved by default.
Frequently asked questions
Does PDLC film use much electricity?
Consumption is low and only occurs in the clear state. Exact figures depend on the film selected and are provided with the quote, based on the documentation of the chosen manufacturer.
Can I install privacy film myself?
It is technically possible on small areas, but cutting to size, glass preparation and electrical connection strongly affect the final result and durability. Professional installation is recommended beyond a few square metres.