Skip to main content

Thermal imaging macro photography on a budget (sort of)

I purchased one of the new FLIR E4 thermal imaging cameras (TIC) a couple weeks back because I am working on a new project called Motobrain. It is an automotive power distribution unit with a nominal current capacity of 100A. For those not in the know, 100A is a TON of current! Because this project is designed to move so much current and will be small I need to understand its thermal characteristics very well. To that end I've been operating the device and taking measurements. What I found is that I just could not get the kind of detail I wanted. The reason is that the resolution of the microbolometer in the FLIR E4 is not very high and the lens does not allow you to get very close to the device under test (DUT). The means that you cannot just zoom in after you take a photo either. So, what is a person to do if they want to take a macro photograph with a consumer grade TIC? Go to Amazon.com of course! I purchased a Gallium Arsenide (GaAs) lens meant for a CO² laser for about $40 and waited patiently for it to arrive (via ox cart it would seem, it took weeks) from China. Then I mounted it up in a highly technical lens mount (a paper CD case cut with scissors and stapled together with the lens inside). This provides me a focus distance of about 2 inches which is great for close up work on a PCB. Different lens sizes will provide different focusing distances. I chose a 50.8mm lens.
The lens.
The lens installed on the TIC
The photo on the left is with the new macro lens attached. The photo on the right shows the previous closest in focus image I could make. Both photos are looking at the same part of the PCB. My lens mount is causing some vignetting which I can fix if I want to bother to make a nicer lens mount on the laser cutter. Honestly I am quite satisfied with the current image quality. If it ain't broke, don't fix it.
The photo on the left shows an SO-8 PowerPak MOSFET glowing nice and warm. You can even see its drain and gate pins. The photo on the right is the same image from the same distance without the lens installed which shows you what it looks like out of focus. This is a significant improvement at a trivial expense compared to the cost of the instrument.
This final image shows the same portion of the PCB as above only with the current flow having just been removed. You can see clearly the temperature gradient as we get further from the MOSFET. Neato!

Special thanks to Mike for the inspiration to do this hack.

Comments

Popular posts from this blog

A Capacitive-Touch Janko Keyboard: What I Did at the 2017 Georgia Tech Moog Hackathon

Last weekend (February 10-12, 2017) I made a Janko-layout capacitive-touch keyboard for the Moog Werkstatt at the Georgia Tech Moog Hackathon. The day after (Monday the 13th), I made this short video of the keyboard being played: "Capacitive Touch Janko Keyboard for Moog Werkstatt" (Text from the video doobly doo) This is a Janko-layout touch keyboard I made at the 2017 Moog Hackathon at Georgia Tech, February 10-12. I'm playing a few classic bass and melody lines from popular and classic tunes. I only have one octave (13 notes) connected so far. The capacitive touch sensors use MPR121 capacitive-touch chips, on breakout boards from Adafruit (Moog Hackathon sponsor Sparkfun makes a similar board for the same chip). The example code from Adafruit was modified to read four boards (using the Adafruit library and making four sensor objects and initializing each to one of the four I2C addresses is remarkably easy for anyone with moderate familiarity with C++), and

Onboard Firmware of the Human Brain

Freesiders are continually tinkering with robotics and other such machinery .  Many of these embedded processors and firmware are becoming open source and every-more diversified in the wake of the modern Maker movement . One notable boost to the hackerspace arsenal is the Arduino (an like platforms).  This offers designers an incredible power to devise not just individual devices but even the emergence of complex, integrated systems . This evolutionary pace of modern technological systems may be significantly faster the biologic system development, but there may be a few well learned tricks yet to be mastered.  It seems that studying how nature has managed to solve many development challenges will aid in designing robotics, where efficiently counts just as much. One  challenge, that is particularly interesting, is data processing.  Artificial intelligence is labored with processing data and producing a meaningful and useful output.  When considering the increase in sensory

Freesiders Hackers Collaborate in Medical / Surgical Research

Published in the May issue of the Journal of Foot and Ankle Surgery : " A Novel Combination of Printed 3-Dimensional Anatomic Templates and Computer-assisted Surgical Simulation for Virtual Preoperative Planning in Charcot Foot Reconstruction ." This collaboration of specialties represents an undertaking by members of Freeside Atlanta , Southern Arizona Limb Salvage Alliance , and The Podiatry Institute .  Charcot foot reconstruction remains on of the most challenging procedures in foot and ankle surgery.  These procedures are often lengthy procedures which can be riddled with complications. With the help of Freeside Atlanta Members, institutional researchers used open source Osirix Image viewer and 3D Software such as Newtek's Lightwave or Blender to create simulated surgical reductions as well as 3D printed templates.  Freeside Atlanta members assisted in providing 3D printing solutions and know-how to the project. Experimental test prints were done on a M