Clear view for cameras and sensors thanks to printed electronics on glass

Outdoor cameras, cameras on rail vehicles or generally equipment in humid environment have a natural enemy: condensation. The countless tiny water droplets on fogged surfaces form a milky-cloudy film that diffuses incoming light, distorts objects and even renders lenses completely or partially ‘blind’.

The solution to this problem is basically simple, but quite complex to implement: it is necessary to prevent the temperature on the glass surface from falling below the dew point. The easiest way to do this is with an electric heater. Irlbacher has developed a modular solution for this task that uses two basic principles: either the finest conductor track structures are printed directly onto the glass with ceramic inks, or the electrical conductivity of a transparent, metallic coating that is structured by laser is used.

In both processes, the heating layer is applied to the inside of the glass to protect it from environmental influences. The electric heater can be easily integrated into clever control strategies so that the protective glass, for example, only heats to just above the dew point without, thus preventing the unnecessary rise in temperature of cameras or sensors. This makes it easy to meet current requirements for sustainability or energy efficiency in mobile devices.

More than 15 years ago, Irlbacher developed a globally patented process for printing filigree conductor tracks with structure widths of less than 200 µm to flat glass and connecting them reliably. Irlbacher also uses this technology, for example, for lighting integrated into the cover glass of display cases, as exhibited at this year’s Light & Building (8 to 13 March in Frankfurt) at stand 8.0-A19. In principle, this special lighting can also be combined with heating, so that the heating function and object lighting can be integrated into one single component. The combination with additional control electronics on the glass pane is also possible with ease.

When even the finest conductor tracks interfere with the imaging geometry, Irlbacher uses flat glass with a transparent, electrically conductive coating. The type of coating or its electrical conductivity depends on the application or the customer’s requirements. However, most applications are based on Laser-structured ITO layers (ITO = indium tin oxide), as this material allows for up to 90% of light transmission. Therefore, ITO is commonly used for high-quality touch and multi-touch solutions.

Irlbacher has all the necessary manufacturing processes in-house. This means that special adaptations to customer requirements are possible at any time. For example, certain areas can be completely omitted and the heating arranged concentrically around the camera’s viewing axis. This allows the maximum optical resolution of the camera to be used without having to rely on expensive special cameras with lens heating.

Both heating variants from Irlbacher are designed for an operating range of -40°C to +80°C, respond very quickly and can therefore be easily integrated into control concepts, for example to reliably prevent protective screens from fogging up when suburban trains enter tunnels. In other applications, Irlbacher’s solutions ensure that automated monitoring systems have a clear view of all entry areas – or that barrier systems at railroad crossings can be reliably monitored in all weather conditions.