Thermal cameras - what's new?
Published: 09 February, 2017
The use of thermal imaging and industry’s awareness of its capabilities has increased dramatically in the last decade and the technology is increasingly percolating through to many areas of our daily lives. The options for measuring temperature and studying thermal performance have never been greater. Not only is there a huge range of models available to suit all application needs but the technology is now eminently affordable and very easy to use. PWE reports.
Thermal cameras now come in various shapes and sizes and while the high-end cameras remain fairly constant in their design, their functionality continues to develop. Increasing value for money applies at the troubleshooting end of the scale too. These cameras now have a variety of sophisticated features and are available in a choice of styles that now also includes pocket-sized. Cameras and thermal cores are also regularly mounted on drones for aerial inspection.
Additionally, engineers have the option to choose from of a growing range of test and measurement instruments with imaging capability or smart phones with integral thermal imaging. Indeed, the development of a thermal micro core, the size of a mobile SIM card, has allowed the technology to be repackaged to meet the needs of an even wider audience. So, what are the options and what’s new?
Horses for courses
The choice of device for temperature measurement essentially depends on the job, whether you simply want to confirm temperature or investigate a wider problem. Another consideration is value for money. Are you best served by a basic device or one whose cost can be justified across a variety of tasks?
All thermal imaging instruments work on the same principle; they are non-contact devices that detect infrared radiation and translate it into a temperature reading. Indeed, a spot thermometer can be considered a thermal camera with just one pixel and it can be very useful for a wide variety of tasks. But it is still simply a tool that measures temperature in one spot, nothing else. This may be sufficient for some jobs but it does not allow the full potential of thermal measurement to be explored.
Sitting between a spot thermometer and thermal imaging camera is an imaging thermometer, a new breed of instrument that combines the two for fast troubleshooting. It provides a non-contact temperature reading while the thermal imaging device will show the relative thermal properties of a subject or targeted area in the context of its surroundings.
Needless to say, an imaging thermometer doesn’t have the sophistication of a dedicated thermal camera but it allows the user to see heat patterns, measure temperature accurately and store measurement data for reporting.
To create this functionality, Andrew Baker, sales director North Europe FLIR Systems Ltd told PWE that his company has combined its Lepton micro longwave detector with a resolution of 160 x 120 active pixels with new technology that it calls Infrared Guided Measurement (IGM). He explains that it allows maintenance professionals to work smarter and more efficiently by visually guiding them to temperature problems that are invisible to the naked eye. In this way, IGM elevates test tools to a whole new level of functionality, saving valuable maintenance time.
Imaging meters
Indeed, the introduction of the micro core and IGM is paving the way for a range of combined technologies. Imaging moisture meters can capture moisture readings below the material surface, either in a non-destructive way or with a wired pin probe. IGM dramatically reduces the time required to assess an area of moisture as it allows the user to scan for problems using thermal imaging and a laser pointer to target the right spot, then confirm and quantify the moisture levels with pin or pinless measurement.
In a similar way, clamp meters with IGM allow electrical overheating to be investigated quickly and safely without requiring any direct contact with the test object. The built-in thermal camera discovers the hot spot and then the clamp meter is applied to verify readouts. Such an instrument is particularly effective when the maintenance engineer is facing cluttered wires or scanning complex panels for hazards.
The most recent addition is an imaging, all-in-one multimeter. Again, it helps the user to pinpoint potential problems at a safe distance from the electrical panel or cabinet. Once IGM has identified an issue, the current, voltage and other measurement functions are employed to confirm findings. Thermal and electrical thermocouple measurements can be viewed simultaneously and the instrument can be supplied with a choice of universal flex probes to increase its scope of application.
Smart additions
Lightweight devices that plug into smart phones to convert them into thermal imaging cameras were introduced a couple of years ago but recently the technology has moved on again. The world’s first smartphone with fully integrated thermal imaging camera is now on the market, a development only made possible by the cost-effective micro radiometric core.
This smartphone is also a great example of how devices, that are entry-level from a thermal imaging point of view, now come complete with highly sophisticated functions, once only the preserve of high-end professional thermal imaging cameras. A typical technology is multi-spectral imaging, developed to make it easier for engineers to interpret thermal images and diagnose problems.
MSX instantly generates a definitive, all-in-one thermal picture that provides as much detail as possible, whether the thermal image appears on the camera screen, a pc, mobile device, smart phone or in a written report. It captures visual data from the built-in digital camera and radiometric data from the thermal camera. Internal software then analyses the image and superimposes key elements from the visual image as a high-contrast ‘skeleton’ on the thermal output.
This all happens in real time and without compromising temperature measurement accuracy or minimising visibility. The result is an image showing unprecedented detail.
With thermal imaging available at the touch of a button, the user can quickly identify gaps in insulation, electrical faults and monitor the performance of machinery. Equally, it can check the gas cylinder level on the barbeque or detect the freshest loaf of bread in a supermarket! Thermal imaging has become truly universal.
For further information please visit: www.flir.com
