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    Light diffusers

    Qualitative solutions for spreading and guiding lightLargest stock of light diffusers, opal sheets and directional diffusersAlways the right light diffuser in stock in various thicknesses, material- and light characteristicsCut to size, laser-cut or milled according to customer requirements
    Materials Downloads Applications Frequently Asked Questions Inspiration Description

    Light diffusers

    Frequently Asked Questions
    Why are there so many different light diffusers?

    The light diffusers are available in different materials, namely acrylic (pmma/Plexiglas®), polycarbonate (lexaan®/makrolon®) and PETG (vivak®). These plastics are having different material characteristics, so there is always a diffuser that is suitable for your application. The diffusers are on stock in various thicknesses, light transmissions, shape and surface.

    When do I choose for an acrylic (Plexiglas®) light diffuser?

    Acrylic is having the best light technical characteristics. Therefore, the starting point for the selection of material is always to choose acrylic. Acrylic has a very high light transmission and is completely 100% colourless. It is UV stable, colour proof, temperature resistant to 80ºC, quite rigid, resistant to many chemicals and 100% recyclable. The fire rating of acrylic is E according to EN13501.

    When do I choose for a polycarbonate (lexaan®) light diffuser?

    We advise to use polycarbonate light diffusers when the diffuser has to be impact resistant or when fire certification Bs1d0 is necessary. Polycarbonate is having a high resistance to temperatures up to 120ºC and barely knows any thickness tolerance. Polycarbonate is less rigid and can therefore be cold bended. Polycarbonate is not UV stable, but many polycarbonate light diffusers are UV proof produced.

    When do I choose for a PETG (vivak®) light diffuser?

    PETG has the advantage that in case of fire less toxic gases are released than in the case of polycarbonate. That is why PETG can only be used at airports for example. Another major advantage is that PETG is food grade certified, can be warm bended and the maximum user temperature is 70ºC.

    What is the difference between standard, professional and advanced light diffusers?

    Standard diffusers are also known as classical opal sheets. The standard diffusers are having a light transmission of 30% and are price-favourable.

    Professional diffusers are having a high light transmission (30%-60%) and still has a good diffusion. These sheets are also price-favourable. Especially when you look at the output of the sheets.

    Advanced diffusers are optimized diffusers with the very best characteristics. The highest light transmission combined with still excellent diffusion. This combination means high efficiency. Advanced diffusers are truly the best diffusers with a matching price.

    What is light transmission?

    The light transmission is the amount of light that is measured on the other side of the light diffuser then where the light source is situated. With other words, the percentage of light that is transmitted through the sheet.

    What is diffusion?

    Diffusion is light scattering. The most common requirement for light diffusers is that the dots of the LEDs should not be visible anymore. But that’s not enough. The light surface must also be even. More about this, you can read the question: “How can I illuminate light diffusers evenly?”

    What is efficiency?

    The efficiency of the light diffusers is the amount of light transmission multiplied with the diffusion. The higher the number, the more efficient is the diffuser. This is our goal, a maximum possible light transmission and the greatest possible diffusion.

    What is the half-value angle?

    The half-value angle has to do with how broad the light is radiating. For example, in case of advertising, advertising must always be observed properly. Then you want the half-value angle to be as large as possible. But in lighting, we just want the light to come where we want it to be. This means a limited half-value angle. The half-value angle is also important when determining the UGR value (unified glare rate). This is a standard that certain lighting needs to meet. Some of our diffusers contribute to achieving the right UGR standard.

    What is UGR value?

    The UGR value (unified glare rate) is a measure of direct glare from light fixtures. A standard which needs to be met for certain lighting. Some of our diffusers contribute to achieving the right UGR standard.

    Which light diffusers does PyraSied have on stock?

    Since there are so many different applications and so many different light sources with a very diverse range of light spectra, angles of egress and temperatures, we have put together a broad range of diffusers with disparate characteristics and properties. Nearly every application comes with its own requirements. With our collection, we want to offer you the desired flexibility. We have light diffusers in stock in sheets, tubes and round rods.

    How can I illuminate light diffusers evenly?

    The core rule for a simple solution with about 30% light transmission is that the distance between the light sources (led strips, for example) is equal to the distance from the light sources to the diffuser sheet.
    However, for an optimal solution, we refer to our very thorough documentation “Select the right light diffuser” (Sied Kooistra, 2013) and “Even backlighting with LEDs is easy” (Sied Kooistra, 2017).

    What distance should I keep between the LED’s and the diffuser sheet?

    By placing a diffusing thing between the observer and the light source. The diffuser should be chosen in a given situation is absolutely not just to answer as there are quite a lot of issues that need to be considered: type of light source, beam angle, spacing, placement, desired light output requirements regarding impact resistance, fire behavior, indoor or outdoor application, serviceability and how long it takes. It is a field of study.

    Circle of life - Alf - Copyirght Janus van den Eijnden fotoboek
    Circle of Light – Amsterdam Light Festival

    For this art object is made use of polycarbonate light diffusers because they are hufterproof. Architect Rob van Houten chose the advanced diffuser Makrolon DX because this diffuser has a high light transmission and makes it beautifully diffuse.

    LumenUs at Glow ’16

    LumenUs is a byTU/e students developed construction that is entirely based on a draw and pressure ratio. The complicated construction consists of rods and steel cables that keep each other in balance. In the artwork the rods are illuminated from the inside. This lighting responds to the impulses of the GLOW audience. Through this interaction with the audience, different colours, through sensors, take over the object slowly.

    Light diffusers from Pyrasied

    PyraSied is specialized in high-quality light diffusers that make light diffuse, bundle, or change the direction. Our light diffuser collection offers an optimal balance between light transmission and the spreading or bundling of light without being distractingly visible. The light diffusers from PyraSied are of very high quality because of the use of nanotechnology, precise control of manufacturing processes, and the best additives and raw materials.

    We are having the right material for every application in stock for you with the required material properties, minimal light loss, and absolute colour purity. Every material can be made cut-to-size or fabricated into a final product. We have our own light technology laboratory and test facilities. This allows us to check the quality of the diffuser: colour brightness, diffusion, and transmission between batches or production runs. We would also be happy to advise you about evenly illuminating our diffusers.

    You can find more information about our light diffusers under the frequently asked questions.


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