Thin bronze strips make light barriers

MicroLouvred screens, with slats 1.27mm wide and 0.18mm thick, prove invaluable for reducing solar glare at low weight and cost, as well as simplifying ventilation grilles and lighting designs.

Based on an idea invented by American John Grebe in 1939, they have now been brought to a manufacturing base in the UK and are in the process of being re-invented for new applications, increased use in light fittings, ventilation grilles and other mechanically engineered products are expected to arise from enhanced manufacturing flexibility, made possible by the introduction of CNC control to the manufacturing process.

The basic idea of MicroLouvre is to miniaturise the slats used in the venetian blind principle so that they have exactly the same effect as large louvres for reducing solar glare, while being much easier to support and handle. This allows them to be fixed to the outside of a window, so that sunlight does not get in through the glass while allowing occupants inside to see out almost without obstruction.

They are made from a special bronze alloy, with an optional matt black paint finish, and can be cut to shape with shears, or fitted to a light fitting or ventilation aperture such as wire mesh. Being closely woven, they also keep out most insects and stop direct rain penetration.

Used in lighting, they are directional and so have been used on trading floors in India, on displays in museums (including the Imperial War Museum) and to shade traffic lights. They also work well as sun visors in cars, stopping glare while allowing the driver to see through them. They offer little resistance to air flow, enabling them to survive 120mph wind speeds, while acting as barriers to sound, reducing direct emissions by up to 50%.

Now that production is in the hands of Smartlouvre Technology in Havant, Hampshire, MD Andrew Cooper has set himself the goal of re-engineering the machines, so that they can produce blinds of different louvre widths and spacing, in a range of materials and finishes.

A sample given to Eureka is made of aluminium alloy instead of bronze. We have seen samples of black painted material laminated between glass sheets to provide glare reduction and/or improved privacy combined with mechanical reinforcement. And the two sides need not be painted the same colour. A guide price for product sold to end users is in the order of £60 to £80/m2, depending on product specification and quantity purchased.

To access this and other related  articles go to www.eurekamagazine, click “Reference Library” and key in ‘louvres’ to the search box.