ANNEX A
Use of the THOR-002 for electronic PCB analysis
The THOR-002 is intended to be a "General use" thermal camera that can produce excellent thermal imagery in a variety of scenarios. Like many such cameras, including those from FLIR, a close-up lens is needed in order to image modern PCB components in any detail. The stated minimum focus distance of the THOR-002 is 30cm and whilst this does provide an image of a PCB of adequate resolution to show "hot spots" it cannot provide the finer detail without a supplemental lens to provide close focus of ~100mm.
In order to test the THOR-002 with a close-up lens I installed a professional AGEMA/FLIR 100mm FL close-up lens and a DIY ZnSe 63mm FL CO2 laser focus lens. OEM supplied lenses tend to outperform DIY ZnSe CO2 laser lenses but it is a common solution to the challenge of close-up thermal imaging when on a tight budget.
The images that follow show just how well the THOR-002 performs when a close-up supplemental lens if attached to it. I was very impressed with the imagery that the camera produced with both the AGEMA/FLIR lens and the DIY ZnSe lens. Attaching the close-up lens provides a "night and day" difference when working on modern PCB's. I have been using the THOR-002 (with 100mm FL close-up lens fitted) for PCB analysis tasks for the past month. It sits on my lab bench waiting for the next patient that needs thermal analysis. Thermal Master do produce their own excellent close-up lens that attaches to the front of the camera using a neat clip assembly. I understand that the close-up lens is only available as part of the enhanced performance THOR-001 kit. The THOR-001 has a minimum focus distance of 80mm when the supplemental close-up lens is fitted. There is also an additional menu entry on the THOR-001 to tell it that the close-up lens is in use and to apply a correction to measurements.
The images of PCB's at a distance of 30cm with no close-up lens fitted reveals the limitation on detail imposed by have 256x192 pixels and a 40 Degree lens producing an IFOV of 2.79 mrad. This is no criticism of the THOR-002, it is just Optical Physics in action. To obtain the needed detail, the camera needs to be closer to the PCB and the camera cannot provide a focused image at such a close distance. As has been stated, a supplemental close-up lens facilitates the closer working distance to reveal greater detail.
Once the close-up lens is fitted, the individual components and IC's may be clearly images and their thermal profile analysed. I have absolutely no hesitation in using the THOR-002 for PCB analysis once the close-up lens is attached. With a DIY ZnSe lens fitted to the THOR-002 camera, a small measurement error will be introduced due to the transmittance figure of the close-up lens. For very accurate measurements, this will need to be considered and corrections applied. Commercial users may wish to consider purchasing the enhanced performance THOR-001 kit with its 80mm FL OEM close-up lens and associated support in the camera menu.
A Philips DVB receiver was used as the test subject for the THOR-002 PCB thermal analysis tests. To provide context, some visible light images of the PCB are attached below.
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