The DIY-Thermocam is a do-it-yourself infrared camera, based on the popular FLIR Lepton long-wave-infrared array sensor. The material price of all components is at about 400€, which makes the device the cheapest standalone solution for thermal imaging on the market.

The aim of this project is to give private persons, educational institutes and companies access to a portable, affordable and customizable thermal imaging plattform.

There are various applications like finding heat leaks in the insulation of buildings, the analysis of electrical or mechanical components, the detection of persons / animals or even mounting it on a drone, together with the additional video out module.

Constructed as a self-assembly solution, the DIY-Thermocam allows you to take advantage of the versatile possibilities of thermal imaging and to save money at one go.

Everything, from software to hardware, is completely open-source! This allows everyone to modify or extend the functionalities of the device to their own needs!

A scientific paper is now available, giving an overview about the whole project and its capabilities.

Make your own

You can make your own DIY-Thermocam at home easily. For the tools, you only need a simple soldering iron, some solder tin, a nippers and a screwdriver. The design of the PCB is very basic: No SMD components, only big through-hole parts and modules. The enclosure can be assembled easily only with bolts & nuts, no glue required.

The DIY-Thermocam works with the FLIR Lepton2 (80 x 60) and the FLIR Lepton3 (160 x 120) LWIR sensor. The hardware revision is detected automatically by the firmware on startup.

The following list provides an overview about the required parts. Most of the parts can be ordered on Digikey.com with free worldwide shipping, the rest can be found on Ebay.com or received from me against a small donation. You also need some small wires and shrink tubes to connect the buttons and switches to the PCB.

Main parts:

	FLIR Lepton with Shutter Long-wave-infrared array sensor	Digikey.com (Lepton2) GroupGets.com (Lepton2) Extract the Lepton3 from a FLIR One V2
	FLIR Lepton Breakout Board Interface the Lepton over SPI / I2C	Digikey.com GroupGets.com
	MLX90614-BCF Spot sensor for absolute temperature measurement	Digikey.com As-electronic.net
	Arducam V2 Mini 2MP Visual camera module	Ebay.com Uctronics.com
	Teensy 3.6 Cortex M4 Microcontroller	Digikey.com PJRC.com Flikto.de
	3.2" TT LCD Display Module Configuration: 5V, Pin header 4-wire SPI, resistive touch, no font chip	BuyDisplay.com
	3.7V Lithium Polymer Battery  With JST-PH connector, max. dimens.: 60mm (w) x 55mm (l) x 6.5mm (h)	Aliexpress.com Sparkfun.com Mikroe.com
	TP4057 Charging Module Including charging LED	Ebay.com Amazon.com
	Pololu U3V12F5 5V voltage booster	Ebay.com Pololu.com Flikto.de
	Printed Circuit Board Against a small donation, you will receive the PCB by post	Donate OSHPark.com Or use the gerber files
	Enclosure Against a small donation, you will receive the enclosure by post	Donate Ponoko.com Or use the design files
	SanDisk 8GB microSD card Can be any size, but needs to be Class4 microSD	Ebay.com Digikey.com
	E-Switch R6ABLKBLKFF Power switch	Digikey.com
	RAFI 1.10107.0110104 Push button	Digikey.com
	E-Switch EG1201A USB power switch	Digikey.com
	JST S2B-PH-K-S Connect the lipo to the PCB	Digikey.com
	Wurth 693063020911 SD slot for the SD card on the PCB	Digikey.com
	MicroSD adapter Short microSD to SD adapter for the internal storage card	Digikey.com
	Display connector 40-pin 2.54mm female header	Digikey.com
	Lepton board connector 8-pin 2.54mm female header	Digikey.com
	Pin header strip 40-pin 2.54mm male header	Digikey.com (2 pcs)
	Keystone 3001 Holder for the coin cell battery	Digikey.com
	CR1220 coin cell battery  Battery for the real-time-clock	Digikey.com
	4.7K 1/4W 1% resistor Multi-purpose resistor	Digikey.com (4 pcs)
	10K 1/4W 1% resistor  Multi-purpose resistor	Digikey.com (2 pcs)
	Lipo protector Double-sided adhesive tape for the lipo protection on the PCB	Digikey.com Or use any thick tape
	Angled microUSB cable For connection of the Thermocam to the PC and charging of the device	Ebay.com Or use any USB cable
	Mini tripod (optional) Used as a stand for the device	Ebay.com Or use any tripod

Other parts:

The other parts can be received against a small donation by post or buy them on your own using the detail information.

The single components are soldered to the PCB as following:

The two M2 x 3.5 distance spacers are put on the left side of the visual camera, so that the parallaxe the FLIR Lepton is minimized. The other two M2 x 3.0 spacers are put under the left side of the camera, the remaining four are placed between the Lepton module and the PCB.

Cut the small trace between VUSB and VIN on the Teensy with a sharp knife:

If you want to understand the connections on the PCB, check out the schematic and the pinmap.

The top side with the buttons and switches connected looks like this:

And here are images from all four sides of the naked device:

In a last step, the naked device needs to be put into the enclosure. Use the bolts, nuts and distance bolts to assemble everything:

Now flash the latest version of the firmware to the device. Check out the firmware update guide for more information.

When you turn the device on afterwards, you should see the first start screen. If any of the components or connections do not work, a diagnostic screen is shown.

In order to understand to various device functionalities, have a look at the manual. The structure of the raw data files is explained here, and the open USB serial protocol here.

Features:

• Fast ARM Cortex M4 processor (240MHz), based on the popular, Arduino compatible Teensy 3.6
• 160 x 120 pixel FLIR Lepton3 long-wave infrared array sensor for live thermographic images
• Frame rate of up to 9 FPS (US export compliance) over the serial connection, 5 FPS on the device itself
• 2 MP visual camera to capture optical images, that can be used in a combined image
• MLX90614 single point-infrared sensor for high-precision spot temperatures (10° FOV)
• HDMI or analog video output capabilities (640x480 pixel) over external video output module (instructions coming soon)
• 3 operating modes: thermal only, thermal + visual, video recording
• 18 different color schemes including rainbow, ironblack, grayscale, hot & cold
• 3.2 inch LCD touch display with bright colors, wide angle and resistive touch
• Save thermal and visual images with a resolution of 640x480 pixels on the device
• Save real-time videos and interval images with different time-lapse settings
• 8GB internal storage, accessible as an exchangeable SD / microSD slot
• 2500 mAh lithium polymer battery for long operation time (4-6 hours)
• Open-source firmware written in Arduino compatible C/C++ code
• Regular firmware updates with new features, flashable over a standalone firmware updater
• Standalone thermal viewer application to save high-quality thermal images & videos on the computer
• Fully compatible to the comprehensive thermal analysis software ThermoVision by Joe-C
• Use simple commands to receive all thermal & configuration data over the USB serial port with high speed

Comparison Table

    <tr>
        <td>
            Thermal resolution
        </td>
        <td>
            80 x 60 or 160 x 120
        </td>
        <td>
            160 x 120
        </td>
    </tr>

    <tr>
        <td>
            Thermal sensitivity <span style="color: #ff0000;"><strong>*</strong></span>
        </td>
        <td>
            &lt; 0.05° C (50 mK)
        </td>
        <td>
            &lt; 0.06° C (60 mK)
        </td>
    </tr>

    <tr>
        <td>
            Thermal temp. range
        </td>
        <td>
            -40° C to 200° C
        </td>
        <td>
            <span style="line-height: 26.6667px;">-20° C to 250° C</span>
        </td>
    </tr>

    <tr>
        <td>
            Field-of-view (FOV)
        </td>
        <td>
            56 deg HFOV, 71 deg diagonal 
        </td>
        <td>
            <span><span style="line-height: 26.6667px;">45 deg × 34 deg</span></span>
        </td>
    </tr>

    <tr>
        <td>
            Display
        </td>
        <td>
            3.2" 320x240 , touch input
        </td>
        <td>
            3.0" 320x240, no touch input
        </td>
    </tr>

    <tr>
        <td>
            Spot sensor temp. range
        </td>
        <td>
            -70° C to 380° C
        </td>
        <td>
            -20° C to 250° C
        </td>
    </tr>

    <tr>
        <td>
            Spot sensor temp. accuracy <strong><span style="color: #ff0000;">*</span></strong>
        </td>
        <td>
            0.5° C over wide range
        </td>
        <td>
            ±2 ° C or ±2%
        </td>
    </tr>

    <tr>
        <td>
            Temp. measurement mode
        </td>
        <td>
            every position, multiple positions
        </td>
        <td>
            spot (center) mode
        </td>
    </tr>

    <tr>
        <td>
            Image modes
        </td>
        <td>
            IR image, visual image, combined
        </td>
        <td>
            IR image, visual image. MSX
        </td>
    </tr>

    <tr>
        <td>
            Color schemes
        </td>
        <td>
            18 different color schemes
        </td>
        <td>
            rainbow, iron, grayscale
        </td>
    </tr>

    <tr>
        <td>
            Storage mode
        </td>
        <td>
            picture and video
        </td>
        <td>
            picture only
        </td>
    </tr>

    <tr>
        <td>
            Storage capacity
        </td>
        <td>
            8 GB internal storage
        </td>
        <td>
            500 sets of images
        </td>
    </tr>

    <tr>
        <td>
            File format
        </td>
        <td>
            standard BMP and raw data
        </td>
        <td>
            standard JPEG and raw data
        </td>
    </tr>

    <tr>
        <td>
            Operation time
        </td>
        <td>
            about 4-6 hours
        </td>
        <td>
            about 4 hours
        </td>
    </tr>

    <tr>
        <td>
            Weight
        </td>
        <td>
            255g
        </td>
        <td>
            575g
        </td>
    </tr>
</tbody>

Device Firmware

The latest releases of device firmware can be found here. For the firmware SDK, check out this instruction.

Thermal Images

More thermal images in full resolution can be found here.

Thermal Image Comparison

This is a comparison between the DIY-Thermocam, the Seek XR and a FLIR E8 thermal imager.

Software

The standalone PC thermal live viewer software allows you to capture HQ thermal and visual images, as well as videos right on the computer. Various settings can be changed over the UI, including a calibration and two different transfer modes. The software is written in Python, so it can be modified to your own needs and executed on any OS. New firmware updates can be flashed to the device easily with the firmware updater application.

There is a powerful thermal analysis software for the PC, called ThermoVision. The image browser can show all thermal & visual images on the internal storage, when the device is connected over USB. They can then be loaded with one click. The software allows you to analyze and edit the thermal raw data files right from the device, create combined images and stream & record live images (thermal & visual) from the Thermocam. You can even set temperature thresholds, which trigger a specific action like opening a file, saving an image or sending a command to the serial port.

The second possibility to view and edit the raw data files right on the PC, is the thermal data viewer. It allows various functions to alter the thermal range, add measurement points as well as various filters. The program is also capable of converting whole folders of raw data frames into images (JPG, BMP or PNG) or avi videos. The live tab allows you to stream live images from the device and the calibration tab offers functions to edit the raw-to-absolution temperature conversion. You can also convert videos or interval pictures with the video converter to avi videos.

Contact me by mail if you have any questions / feedback / improvements

Last updated: 30.01.2017