Expert Interview with Ronen Lin of Smart Films International

It seems that Smart Films International is a pioneer in commercialising smart glass. What attracted you in the first place to the smart glass market?

Smart Films International’s journey started 20 years ago as a start-up company with the vision of being the leading provider of flexible Liquid Crystal optical shutters.

Years of investment in research and development led us to a high quality Smart Film technology, as well as unique production methods and roll-to-roll capabilities. We were inspired by the endless possibilities of adding a technology layer to a conventional glass or plastic based substrate, resulting in enhanced or new products.

Today we are well established for Smart Glass as well as having full capabilities to customise LC emulsions for other applications such as dynamic automotive visors, ski goggles, strobe glasses and more.

Which benefits of smart glass are most important to your customers?

When we firstly set our product development goals and specifications we aimed for long term reliability with no compromise on high electro-optical qualities.

It goes back to our core production philosophy and methodology. We developed an exclusively water-based LC emulsion which is more difficult to produce, but which ensures a reliable product because we avoid solvents and chemical reactions.

We achieve high electro-optical qualities such as transparency and haze by controlling the LC droplet size and shape. Although our NCAP (‘Nematic Curvilinear Aligned Phases’) production process is more complicated and difficult to control compared with phase separation methods, NCAP Smart Film products offer improved optical qualities while ensuring a long term stability and reliability.

Which smart glass market segments do you see growing the fastest in the next 5 years and why?

It is the beginning of the golden era of the Smart Glass industry. We are witnessing a global awareness and recognition of Smart Glass, its potential and value. We see investments in Smart Glass companies by industry leaders such as Merck, Saint Gobain and others.

Smart Glass evolved from mainly a switchable glass for interior spaces to a family of products for privacy and solar control in architecture and transportation, as well as in interior and exterior applications.

During the next 5 years I believe that we will witness the following trends:

• Architecture:
  • Privacy Glass: We will see a growing demand for traditional Smart Glass for privacy in interior space applications (hotels, hospitals, corporations and residential properties). This will be possible mainly due to an increased volume of production and continuing cost reduction.
  • Solar Control Glass: We will see increasing demand for exterior glass for solar control, which will be driven mainly by electrochromic and thermochromic glass. Prices will need to further adjust in order to penetrate the anticipated mass volumes.
• Transportation:
  • Looking into the future of the automotive industry, namely autonomous vehicles, car manufacturers are looking for Smart Glass solutions that will automatically adjust privacy and solar control. We will see growing demand and the quantities will ramp up.
  • Marine and Aviation will also start to adopt Smart Glass for solar control and privacy applications. Both automotive and aviation markets are regulated with very demanding requirements, which will limit the market growth in these industries.

I see you have recently started to commercialise thermochromic smart glass also. Why is this product line significant to your customers?

As part of global environmental protection, sustainability and wellbeing awareness, Smart Films International decided to launch a production of thermochromic glass.

It is a glass with a dynamic range of tint. The glass will change its tint level intuitively based on solar heat, while maintaining a comfortable level of natural lighting inside the space during the hours of daylight.

Thermochromic glass is activated by the sun, which means it does not need any power source and it does not consume any energy. It is important to our customers as it saves on heating, ventilation and air cooling costs.

Most importantly though, it enables natural light which is proven to be healthy to human beings. With natural light we are more productive at work, education is more efficient, recovery is faster in medical centers and in general we are happier.

Can you explain why the LC micro-droplets in your NCAP PDLC process result in lower haze in your products?

The optical quality of Smart Film depends on various parameters such as the refractive index of the polymer, clarity of the matrix film but most importantly on the size and form of the LC micro droplets.

Spherical LC droplets result in a strong index mismatch in off-axis directions, which minimises in deformed LC droplets. The size and shape of the LC droplets within the Smart Film are one of the most critical factors in determining the electro-optical properties of the Smart Film.

Properties like haze, film absorbance, switching voltage, and response time all depend on the size and shape of the LC droplets. Smart Film with an optimised distribution of sizes and shapes will exhibit excellent electro-optical properties, and films with sub-optimal distributions will show poor properties.

The shape of the LC droplets will strongly affect the alignment of the liquid crystal within each domain. Since the alignment of the LC determines the Smart Film electro-optical properties, these domain shapes are intimately linked to the Smart Film properties.

LC droplets that are highly flattened or strongly distorted will require high switching voltages. Droplets that are shaped to induce the LC to lie perpendicular to the Smart Film face will not contribute to the Smart Film performance at all, as they are oriented along a direction that will be more-or-less the same whether there is an applied voltage or not.

Analysis has shown that the distribution of LC droplet shapes within our Smart Film is optimal and nearly each LC droplet is a slightly flattened oblate spheroid.

The LC domains tend to form a collection of randomly oriented domains, maximising the optical performance available with that set of materials.

About Ronen Lin

Ronen Lin is the Executive Director of Smart Films International and an experienced founder with passion and enthusiasm for creating business in the Hi-Tech environment. With professional skills in finance & business development, Ronen pursues partnerships, entrepreneurship and venture capital.