LED illuminators are designed to enhance the performance of a security system, and here, Raytec a specialist in this field, explores the lighting requirements for sites using perimeter protection systems, and identifies some of the key elements to consider when specifying lighting for these applications.
Often one of the first lines of defence, a typical high-security site will use cameras to surround the perimeter fence line and may also use several other security devices as part of the system. For the cameras to be effective and provide useful images to security staff, day or night, high quality illumination is essential.
From private property, to large critical infrastructure sites, the types of sites requiring perimeter protection are wide and varied, but all tend to have common security goals. They’re deployed to restrict access, detect and deter crime, protect important assets.
The key things to consider when specifying an illuminator for use as part of a perimeter protection system:
Light type
Infrared and white-light
Infrared (IR) illumination is the most common type of light used around a perimeter fence line. IR omits zero light pollution (so not to disturb the surrounding area), but crucially, it allows the camera to capture night-time images covertly, without alerting potential intruders or giving them light to work by. Once the camera has detected an intruder, the site may choose to raise an alarm. This is where white-light is often deployed; automatically triggered as a flashing deterrent to ward off an intruder, or used to provide accurate positive identification of the intruder. Only using white-light when it’s needed ensures light pollution is kept to a minimum while still providing optimum levels of security. In some instances, white-light may still be chosen to illuminate the entire perimeter, but due to light pollution, and the fact that the camera is more receptive to IR, means white-light is often preferred as a deterrent.
Hybrid
Another option which specifiers could consider is the use of hybrid illuminators. Hybrid illuminators provide an all-in-one solution, combining both IR and white-light into a single unit. This means one illuminator can be used for both covert surveillance, and as a white-light deterrent. As a 2-in-1 solution, Raytec’s Vario2 hybrid doesn’t compromise on performance, achieving the same power and distance as two dedicated illuminators. Hybrid allows the user to control the wavelength and switch seamlessly between IR and white-light.
Quality and distance
Perimeter fence lines often cover large areas, so distance and coverage of an illuminator is one of the main things for a specifier to consider. However, it’s also equally important to consider how the illuminator will assist the camera in obtaining the highest quality images. Illuminators able to deliver longer distances may allow cost savings by reducing the total number of illuminators across the site. It may also allow the user to reduce costs in terms of the numbers of cameras, lighting columns, cabling and other ancillary equipment needed as part of the installation.
Manufacturers often publish data regarding the distances which their illuminators can achieve, however it’s important to understand that between different manufactures, the image quality produced at the same quoted distance could vary significantly. Reputable manufacturers should be able to provide in-depth performance data about their illuminators, while carrying out a detailed lighting design is always recommended to ensure the required light levels are achieved.
Hot spot reduction
One way to help ensure a good image is to select an illuminator which uses technology which reduces hot spots and provides an even image across the entire scene. For example Raytec’s Vario2 range uses hot-spot reduction technology to deliver a highly diffused, elliptical beam shape which targets the light where it’s needed. This supports longer distances, minimises light wastage, and ensures even distribution of light throughout the scene. The HRT system also prevents over-exposure of foreground objects; light uniformity is crucial in ensuring hot spots are minimised.
Hardware integration
For applications using devices such as IP cameras, or PIRs, specifying an IP enabled illuminator capable of providing an automated lighting response, is essential. For example, if a PIR sensor detects movement from an intruder, an alarm could be raised to automatically turn on the white-light (so the intruder can be positively identified) or put the lamps into deterrent mode (to ward off the intruder).
Camera analytics
Many systems today are using camera analytics, but they are only as effective as their ability to provide a consistent, clear image. This is where lighting plays an important role. Camera analytics will often require increased light levels compared to standard applications, because sometimes even with the the most effective cameras on offer, no light means no camera analytics.
Software integration
Specifiers should also consider the security management platform their site is using to monitor and control cameras, illuminators and other devices across the site. In terms of specifying an illuminator, it’s important to choose one which can be integrated with the security management platform in use by the site, so it can be controlled easily and lighting responses set-up to be triggered by other detection devices. For example, Raytec has a number of software plug-ins which facilitate integration of Vario2 IP illuminators with a host of security management platforms.
Other considerations include easy specification and commissioning to potentially save time and money during the initial phases and up to the commissioning stage; flexibility, such as interchangeable lenses which help the installer adapt the lighting to suit the installation; and finally, a 2D or 3D lighting design to help ensure the correct light levels are achieved across the site, to act as a reference for the installer and to bring peace of mind to the specifiers.
