Smart glass technology has rapidly become one of the most exciting innovations in modern architecture. From conference rooms and healthcare facilities to luxury residences, switchable glass allows designers to control privacy, light, and spatial flexibility with the touch of a button.
However, not all smart glass technologies operate the same way. The two most commonly discussed technologies are PDLC and PNLC.
Understanding the difference between these systems is essential when specifying smart glass for architectural projects.
What is PDLC Smart Glass?
PDLC (Polymer Dispersed Liquid Crystal) is the most widely known type of switchable glass.
In PDLC technology:
• When electricity is applied, the liquid crystals align and the glass becomes transparent.
• When power is turned off, the crystals scatter light and the glass becomes opaque.
PDLC has been used for many years in:
• office partitions
• conference rooms
• residential bathrooms
• healthcare privacy glass
Its primary advantage is simplicity and wide availability.
However, PDLC also has limitations in applications where fail-safe privacy is required.
What is PNLC (Reverse Switchable Glass)?
PNLC (Polymer Network Liquid Crystal) is often referred to as reverse switchable glass.
In PNLC technology the operating principle is reversed:
• When power is OFF, the glass remains transparent.
• When power is ON, the glass switches to opaque privacy mode.
This configuration offers several important benefits for architectural design.
PNLC allows glass to remain clear under normal conditions, while enabling privacy only when needed.
Key Differences Between PDLC and PNLC
| Feature | PDLC | PNLC |
|---|---|---|
| Default state | Opaque | Transparent |
| Privacy activation | Power OFF | Power ON |
| Fail-safe condition | Private | Transparent |
| Best applications | Conference rooms, partitions | Luxury architecture, glass railings, specialty design |
| Design flexibility | Standard | High-end architectural |
When Should Architects Use PDLC?
PDLC is commonly used in applications where privacy is the default requirement.
Typical examples include:
• office meeting rooms
• hospital patient rooms
• bathroom partitions
• interior glass walls
In these environments, privacy is needed most of the time, so PDLC works well.
When PNLC Becomes the Better Solution
PNLC is especially valuable in architectural situations where glass should remain visually open and transparent most of the time, but privacy may occasionally be required.
Examples include:
• luxury residential architecture
• glass railings and balustrades
• high-end commercial interiors
• hospitality design
• architectural feature walls
Because the glass remains clear when unpowered, PNLC allows designers to maintain openness while still having instant privacy when required.
A New Generation of Smart Glass
Advances in switchable glass technology continue to expand what architects can achieve with glass.
Modern smart glass systems allow spaces to become flexible, dynamic, and responsive to changing needs without sacrificing aesthetics.
Whether PDLC or PNLC is the right choice depends on the functional requirements of the project and the design intent of the architect.
Need Smart Glass for Your Project?
PriWatt® switchable glass technologies provide advanced solutions for architects, designers, and builders looking to integrate intelligent glass into modern spaces.
Our team can help you evaluate the best technology for your project.
Request a quote or technical consultation today.
PDLC vs PNLC: The Smart Glass Showdown
Smart Glass Technology · In-Depth Comparison
PDLC vs. PNLC
Two technologies, one ambition — understanding the real differences in switchable glass
TechnologyArchitecture & DesignSmart Materials
Smart glass has quietly revolutionized how we think about privacy, light control, and energy efficiency in architecture, automotive, and interior design. At the heart of this revolution are two dominant liquid crystal technologies — Polymer Dispersed Liquid Crystal (PDLC) and Polymer Network Liquid Crystal (PNLC) — that look similar on the surface but behave in fundamentally different ways.
Whether you’re an architect specifying glazing for a luxury office, a designer outfitting a high-end residential project, or simply a curious technologist, this guide breaks down everything you need to know to choose between these two remarkable technologies.
What Are They, Exactly?
A primer on the science behind the glass
PDLC
Polymer Dispersed Liquid Crystal
Liquid crystal droplets are randomly dispersed within a solid polymer matrix. In its natural state (no voltage), droplets scatter light and the glass appears opaque — milky white. Apply voltage, and the crystals align, letting light pass through to create transparency.
PNLC
Polymer Network Liquid Crystal
Instead of discrete droplets, a continuous polymer network is interwoven with liquid crystals. The network structure gives much finer control over crystal orientation, resulting in superior optical clarity when switched on, and often a deeper, more uniform dark state when off.
Both technologies are sandwiched between two layers of ITO (Indium Tin Oxide)-coated glass or film, and both require an AC electrical current to switch states. The key differences lie in their microstructures — and those differences cascade into very distinct real-world performance characteristics.
“PDLC is the workhorse of smart glass. PNLC is the thoroughbred — faster, clearer, but demanding more from its environment.“
— ✦ —
Side-by-Side Comparison
The numbers that matter in real-world applications
| Attribute | PDLC | PNLC |
|---|---|---|
| OFF-state appearance | Milky white / translucent | Dark, near-opaque (gray/black) |
| ON-state clarity | Good — slight haze remains | Excellent — high optical purity |
| Haze level (ON) | 3–10% | <1–3% |
| Switching speed | 10–100 milliseconds | 1–10 milliseconds |
| Operating voltage | 40–110V AC | 5–60V AC |
| Power consumption | ~5 W/m² | ~1–3 W/m² |
| Privacy in OFF state | Moderate (diffuse scatter) | High (absorbs/blocks light) |
| Viewing angle | Wide but with scatter | Wide with minimal distortion |
| Cost | Lower ($50–$150/m²) | Higher ($150–$400+/m²) |
| Durability / lifespan | Very mature technology | Still maturing commercially |
| Retrofittable as film | Yes — widely available | Limited availability |
| Temperature sensitivity | Moderate | More sensitive to extremes |
— ✦ —
PDLC in Depth
The established champion of privacy glass
PDLC has been commercially available since the late 1980s and today represents the vast majority of installed smart glass worldwide. Its maturity means an established supply chain, well-understood failure modes, and competitive pricing across a wide range of suppliers.
The technology’s hallmark is its scattering approach to opacity. When voltage is removed, the randomly oriented liquid crystal droplets diffuse incoming light in all directions — creating that characteristic frosted appearance. This works beautifully for privacy partitions in offices, hospital rooms, and residential bathrooms where a diffused, soft opacity is perfectly adequate.
However, the residual haze when the glass is “on” (transparent) is PDLC’s Achilles’ heel. In high-clarity applications — retail display cases, projection screens, premium automotive glazing — that few percent of haze can be noticeable and limiting.
PDLC Strengths
- Widely available, established technology
- Lower cost per square meter
- Available as self-adhesive retrofit film
- Broad supplier ecosystem
- Proven long-term reliability
- Works well in most temperature ranges
PDLC Weaknesses
- Residual haze degrades transparency quality
- OFF state is milky, not a deep privacy dark
- Higher operating voltage requirements
- Slower switching compared to PNLC
- Light scatter visible in oblique viewing angles
PNLC in Depth
The next generation — precision engineered for clarity
PNLC emerged from research aimed at solving PDLC’s optical limitations. By forming a continuous polymer network rather than isolated droplets, manufacturers can control the alignment of liquid crystals far more precisely. The result is a film that achieves near-crystal clarity in the ON state and a genuinely dark, absorbing OFF state — more akin to electrochromic glass in appearance, but with the snap-switching speed of liquid crystal technology.
This dark-state characteristic is highly desirable in cinematic, hospitality, and luxury automotive contexts. A boardroom that dims to a near-blackout state for presentations — without drawing curtains — is a compelling proposition that only PNLC can deliver among LC-based technologies at high switching speeds.
The trade-off? Cost, supply-chain maturity, and greater sensitivity to manufacturing consistency and temperature extremes. As the technology scales commercially through the mid-2020s, many of these drawbacks are narrowing — but PNLC remains a premium choice requiring careful specification.
PNLC Strengths
- Exceptional optical clarity when ON
- Deep, dark opacity when OFF — true blackout potential
- Ultra-fast switching (under 10 ms)
- Lower power consumption
- Finer grayscale dimming control
- Superior for projection and display applications
PNLC Weaknesses
- Significantly higher cost
- Fewer established suppliers
- Less widely available as retrofit film
- Greater temperature sensitivity
- Longer-term durability data still accumulating
— ✦ —
Which Technology Fits Your Project?
Matching the right glass to the right application
Office Partitions PDLC is ideal. Instant privacy on demand, cost-effective at scale, and retrofit film options allow existing glass to be upgraded easily.
Luxury Automotive PNLC wins. Faster switching, lower voltage, and a cleaner dark state meet the exacting standards of premium OEMs and after-market installers.
Retail Display PNLC for flagship stores where optical purity matters; PDLC is acceptable for secondary partitions and back-of-house dividers.
Healthcare / Hospitals PDLC is the proven choice — cost-efficient, hygienic wipe-down surfaces, and long operational track record in clinical environments.
Home Cinema / AV PNLC’s deep dark state and fast switching make it far superior for projection screens and home theater environments.
Residential Bathrooms PDLC covers the use case perfectly — privacy on demand, humidity tolerance, and affordable pricing for smaller panel sizes.
The Bottom Line
PDLC remains the pragmatic, proven choice for most commercial and residential privacy glass applications — affordable, reliable, and backed by decades of real-world performance data.
PNLC is the technology to choose when optical excellence, speed, or a genuinely dark off-state are non-negotiable — and when budget allows for the premium that precision demands.
As PNLC manufacturing scales and costs compress through the late 2020s, the gap between these two technologies will narrow. For now, the right choice depends entirely on your project’s priorities.
Smart Glass Technology Blog · Exploring the Science of Switchable Materials
Smart Glass Technology · In-Depth Comparison
PDLC vs. PNLC
Two technologies, one ambition — understanding the real differences in switchable glass
Smart glass has quietly revolutionized how we think about privacy, light control, and energy efficiency in architecture, automotive, and interior design. At the heart of this revolution are two dominant liquid crystal technologies — Polymer Dispersed Liquid Crystal (PDLC) and Polymer Network Liquid Crystal (PNLC) — that look similar on the surface but behave in fundamentally different ways.
Whether you’re an architect specifying glazing for a luxury office, a designer outfitting a high-end residential project, or simply a curious technologist, this guide breaks down everything you need to know to choose between these two remarkable technologies.
What Are They, Exactly?
A primer on the science behind the glass
Polymer Dispersed Liquid Crystal
Liquid crystal droplets are randomly dispersed within a solid polymer matrix. In its natural state (no voltage), droplets scatter light and the glass appears opaque — milky white. Apply voltage, and the crystals align, letting light pass through to create transparency.
Polymer Network Liquid Crystal
Instead of discrete droplets, a continuous polymer network is interwoven with liquid crystals. The network structure gives much finer control over crystal orientation, resulting in superior optical clarity when switched on, and often a deeper, more uniform dark state when off.
Both technologies are sandwiched between two layers of ITO (Indium Tin Oxide)-coated glass or film, and both require an AC electrical current to switch states. The key differences lie in their microstructures — and those differences cascade into very distinct real-world performance characteristics.
“PDLC is the workhorse of smart glass. PNLC is the thoroughbred — faster, clearer, but demanding more from its environment.”
Side-by-Side Comparison
The numbers that matter in real-world applications
| Attribute | PDLC | PNLC |
|---|---|---|
| OFF-state appearance | Milky white / translucent | Dark, near-opaque (gray/black) |
| ON-state clarity | Good — slight haze remains | Excellent — high optical purity |
| Haze level (ON) | 3–10% | <1–3% |
| Switching speed | 10–100 milliseconds | 1–10 milliseconds |
| Operating voltage | 40–110V AC | 5–60V AC |
| Power consumption | ~5 W/m² | ~1–3 W/m² |
| Privacy in OFF state | Moderate (diffuse scatter) | High (absorbs/blocks light) |
| Viewing angle | Wide but with scatter | Wide with minimal distortion |
| Cost | Lower ($50–$150/m²) | Higher ($150–$400+/m²) |
| Durability / lifespan | Very mature technology | Excellent — proven in commercial deployments |
| Retrofittable as film | Yes — widely available | Available via PriWatt and select suppliers |
| Temperature sensitivity | Moderate | Good across standard operating ranges |
PDLC in Depth
The established champion of privacy glass
PDLC has been commercially available since the late 1980s and today represents the vast majority of installed smart glass worldwide. Its maturity means an established supply chain, well-understood failure modes, and competitive pricing across a wide range of suppliers.
The technology’s hallmark is its scattering approach to opacity. When voltage is removed, the randomly oriented liquid crystal droplets diffuse incoming light in all directions — creating that characteristic frosted appearance. This works beautifully for privacy partitions in offices, hospital rooms, and residential bathrooms where a diffused, soft opacity is perfectly adequate.
However, the residual haze when the glass is “on” (transparent) is PDLC’s Achilles’ heel. In high-clarity applications — retail display cases, projection screens, premium automotive glazing — that few percent of haze can be noticeable and limiting.
PDLC Strengths
- Widely available, established technology
- Lower cost per square meter
- Available as self-adhesive retrofit film
- Broad supplier ecosystem
- Proven long-term reliability
- Works well in most temperature ranges
PDLC Weaknesses
- Residual haze degrades transparency quality
- OFF state is milky, not a deep privacy dark
- Higher operating voltage requirements
- Slower switching compared to PNLC
- Light scatter visible in oblique viewing angles
PNLC in Depth
The next generation — precision engineered for clarity
PNLC emerged from research aimed at solving PDLC’s optical limitations. By forming a continuous polymer network rather than isolated droplets, manufacturers can control the alignment of liquid crystals far more precisely. The result is a film that achieves near-crystal clarity in the ON state and a genuinely dark, absorbing OFF state — more akin to electrochromic glass in appearance, but with the snap-switching speed of liquid crystal technology.
This dark-state characteristic is highly desirable in cinematic, hospitality, and luxury automotive contexts. A boardroom that dims to a near-blackout state for presentations — without drawing curtains — is a compelling proposition that only PNLC can deliver among LC-based technologies at high switching speeds.
In most installations, PNLC glass achieves 93–94% light transmission in the ON state — exceptionally high, though worth noting for projects where the absolute clarity of standard uncoated glass is the benchmark.
PNLC Strengths
- Exceptional optical clarity when ON
- Deep, dark opacity when OFF — true blackout potential
- Ultra-fast switching (under 10 ms)
- Lower power consumption
- Finer grayscale dimming control
- Superior for projection and display applications
PNLC Considerations
- ON-state transparency reaches 93–94% — not fully clear like standard glass
When it comes to PNLC glass and film in the United States, one name stands above the rest: PriWatt. As the leading domestic manufacturer of PNLC smart glass and switchable film, PriWatt has been instrumental in bringing this next-generation technology out of the laboratory and into real-world commercial and architectural applications across the country.
Unlike many competitors who rely on overseas production, PriWatt manufactures its PNLC products domestically — giving architects, glazing contractors, and designers the confidence of consistent quality, faster lead times, and direct technical support. Their product line covers everything from laminated smart glass panels for new construction to self-adhesive PNLC retrofit film that can transform existing glazing into privacy glass without full replacement.
“PriWatt has made PNLC accessible to the American market — closing the gap between cutting-edge optical performance and practical, project-ready delivery.”
For projects where PNLC is the right call — luxury hotels, corporate boardrooms, high-end residential, premium automotive, or AV environments — PriWatt is the go-to source for sourcing, specification, and supply in the US market. Their team works directly with architects, interior designers, glazing subcontractors, and systems integrators to ensure every installation performs to its full potential.
Which Technology Fits Your Project?
Matching the right glass to the right application
The Bottom Line
PDLC remains the pragmatic, proven choice for most commercial and residential privacy glass applications — affordable, reliable, and backed by decades of real-world performance data.
PNLC is the technology to choose when optical excellence, speed, or a genuinely dark off-state are non-negotiable — and when budget allows for the premium that precision demands.
As PNLC manufacturing scales and costs compress through the late 2020s, the gap between these two technologies will narrow. For now, the right choice depends entirely on your project’s priorities.
Specifying PNLC for your next US project? PriWatt is the country’s leading manufacturer — offering both laminated glass panels and retrofit film with full domestic support.
