The high-performance nonwovens in the product portfolio consist of the finest polyester special fibers, which interweave and overlap thanks to a special manufacturing process in order to diffuse and distribute dots of light over a larger area – even in cases where there is a short distance from the light source. The high diffusion capability of the diffusing media makes it possible to create lightweight and compact lighting systems.
To date, primarily coated diffuser films or filled diffuser plates have been used for LED lighting applications. In comparison, the Light Diffuser impresses not only with a high light diffusion capability but also with a low material thickness between 0.05 and 0.12 mm, a reduced weight of less than 85 g/m2 and a higher material strength. Its availability in rolls of up to 1.8 m width and 5,000 m length also enables efficient processing.
The goal of the product development was to design a nonwoven for effective distribution of LED dots over a wide area that features exceptional uniformity and high translucency. Alongside the ambitious optical properties, the product also lives up to the mechanical demands that arise in the manufacturing and use of LED lighting systems. In particular, the ability to withstand ambient temperatures of ≥ 80°C and the low susceptibility to scratches and optical defects such as those which can occur in the manufacturing of luminaires were important milestones in the development. The Light Diffuser has already proven itself in practice and is used in a variety of luminaire models. In working with lighting experts and manufacturers, it has become clear that the diverse range of designs require a variety of optical and mechanical properties from light diffusing media. The product portfolio was therefore expanded to six products in order to encompass additional applications. These include four polyester nonwovens with defined diffusion and transmission levels as well as a film-reinforced and a self-adhesive variant.
Potential areas of application include functional design luminaires with direct and indirect illumination components: Because between 50 and 77% of the light striking the nonwoven passes through and the remainder is reflected without losses, both the workstation and the ceiling can be flooded with light to produce a pleasant base of illumination. When used in advertising displays, or the LED lighting panels that are increasingly common in offices and public buildings, the Light Diffuser also yields many benefits: Its combination of low thickness, maximum diffusion of light irregularities and minimum space requirements lives up to the trend toward increasingly flat designs.
Even in lighting systems with direct backlight, such as LED downlights, the high light diffusion capability of the innovative Light Diffuser nonwoven allows it to effectively diffuse the dots of light despite a minimal distance from the light source.
In edge-lit applications, such as LED panels, which typically feature asymmetrical and uneven light emission from the light guide plate, the Light Diffuser nonwoven homogenizes the emitted light to achieve a light output efficiency of up to 92%.
In systems with light-guiding films, the nonwoven diffuses focused incoming light over the entire surface of the material, guaranteeing its even introduction into the structured film for a uniform, directed cone of light.
In March, the Light Diffuser product range was officially presented at the world’s leading trade fair in the lighting industry, Light & Building 2018 in Frankfurt. “The trade fair presentation was a complete success for us. The use of nonwovens as a light diffuser in lighting applications is an innovation not only for Freudenberg but for both the lighting and nonwoven worlds,” explains Product Manager Jochen Bialek. “With the further development and marketing of our Light Diffuser portfolio, we will open up additional market potential, such as interior automotive lighting, backlit print substrates and large-scale lighting installations.”