Switchable glass carries a liquid-crystal or electrochromic layer between two panes. Power it and the particles align so the glass is clear; cut the power and they scatter, leaving a uniformly opaque panel. It replaces a blind with the glass itself, which is why it turns up in boardrooms, consulting rooms and bathrooms where a curtain would be impractical.
The technology
How it works
Polymer-dispersed liquid crystal is laminated between two glass panes. With no voltage the crystals sit at random and scatter light, so the panel reads as translucent white. Applying mains voltage through a transformer aligns them and the glass clears in well under a second. Switching is instant and effectively unlimited.
An electrochromic coating changes tint rather than opacity, darkening progressively as a small DC voltage is applied. It holds its state without continuous power and is used where solar control matters as much as privacy, because the tinted state also cuts heat gain.
Panels are driven by a transformer that can be switched from a wall plate, a building management system, an occupancy sensor or a phone. The cable exit point has to be decided before manufacture, because the busbar position is fixed during lamination.
The opaque state is diffuse, not blackout. It blocks line of sight and reads as frosted; it does not darken a room. Where the requirement is blackout, this is the wrong product and a blind behind clear glass is the right one.
Applications
Where it is specified
The commonest application. A glazed meeting room stays open and daylit through the working day and turns private for the duration of a confidential conversation, without the dust and maintenance of blinds in a sealed cavity.
Consulting rooms, ICU bays and observation windows where a clinician needs to see in and a patient needs privacy on demand. The sealed laminated construction wipes clean, which a fabric blind does not.
Where a bathroom faces a view worth keeping, a switchable screen gives the view when the room is empty and privacy when it is not.
Shopfronts that switch opaque out of hours, and display cases that reveal on approach. The PDLC layer can also act as a rear-projection surface in its opaque state.
The TPRS product
TPRS Wizardglass
TPRS Wizardglass redefines space with smart electrochromic technology that shifts from transparent to opaque at the touch of a button. Ideal for creating seamless comfort without sacrificing privacy, it transforms windows, partitions, and facades into interactive design elements. Wizardglass enhances energy efficiency by controlling glare and solar heat while maintaining a sleek, modern aesthetic. Whether in luxury residences, board rooms, or hospitality spaces, it delivers both visual openness and controlled seclusion. With TPRS Wizardglass, experience the future of intelligent glass.
Sectors
Where TPRS supplies this
Glass Insights
FAQs
Switchable glass is laminated glass with an electrically controlled layer between the panes that changes the glass from transparent to opaque. The common types are PDLC, which switches instantly between clear and a frosted white, and electrochromic, which tints gradually and holds its state without power.
PDLC glass is clear only while energised, so it draws power continuously in its transparent state, though the consumption is small — comparable to a low-wattage lamp per square metre. Electrochromic glass draws power only while changing state and holds its tint afterwards, so it uses far less over a day.
Electrochromic glass is made for external glazing and is normally supplied inside an insulated unit, where the tinting also reduces solar gain. PDLC is more commonly an internal product; for external use it must be built into a sealed insulated unit to protect the film from moisture and ultraviolet exposure.
Maximum panel size is set by the film width and the lamination line rather than by the glass. Send the panel schedule with the largest dimension marked and TPRS will confirm what can be produced in one piece and where a join would fall.
Yes. Because the switchable layer is laminated between two panes, the finished panel is laminated glass and behaves as one: if broken, the fragments are retained on the interlayer. Specify toughened outer panes where the position also calls for impact resistance.
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Enquiries
Send the drawing, get a specification
Panel sizes, thickness, make-up and quantity are all TPRS needs to quote. Processing runs from two plants in Puducherry and Dharwad, with offices in Chennai and Bangalore.