PI 640i Thermal Microscope

The PI 640i infrared microscope kit is perfect for engineers who need reliable temperature data on small electronic devices or Micro-Electro-Mechanical Systems (MEMS). The ability to detect thermal variations and take measurements on small targets relies on the resolution of the detector. The optics focus heat energy from the device onto the IR camera’s detector elements. This setup allows for precise temperature measurements, which are crucial for detailed thermal analysis of miniature components.

Many engineers notice that temperature readings taken with contact thermocouples on small electronic devices often do not match those taken with a properly equipped online thermal camera. This difference is common when dealing with small targets because the thermocouple can act as a thermal bridge, drawing heat away from the target. In these situations, using a non-contact infrared camera provides more accurate measurements since it avoids the heat conduction issues seen with contact methods.

Just like microscopes that work in the visible spectrum, selecting the right optic for any application involves balancing the total observable field of view and the smallest target to observe and measure. The PI 640i microscope objective can detect temperature changes on targets as small as 28 µm while covering a total field of view of 18.2 mm x 13.8 mm. A high-resolution IR camera with standard wide field of view optics will only provide accurate measurements of microelectronic targets when paired with proper infrared microscope optics. The PI 640i microscope packages combine a high-resolution online thermal camera, German-designed infrared microscope objectives, and a precision mounting stage for adjusting working distance, ensuring accurate thermal measurement and analysis of small targets.

Most IR camera manufacturers will highlight a single pixel size or IFOV (Instantaneous Field of View) to showcase a camera’s ability to resolve small targets. However, accurately measuring temperature with an infrared camera requires more than one pixel. Infrared cameras with smaller detector pitch or pixel sizes may need up to 7 x 7 pixels to deliver temperature measurements within the camera’s accuracy range. The MFOV (Measurement Field of View) specification is important for achieving correct temperature readings, as it considers the number of pixels needed for accuracy.

In addition to low thermal noise, the ideal pixel pitch size of 17 µm for long-wavelength infrared radiation allows a small Measurement Field of View (MFOV) of just 3 x 3 pixels, unlike other thermal cameras with smaller pixels. The high quality and larger size of the optics ensure excellent image quality, reducing distortion and providing uniform attenuation across the entire image. A variety of interchangeable lens optics are available to properly frame the target and maximize the pixel count for measurement. The infrared camera operates at a frame rate of 32 Hz in standard mode or 125 Hz in high-speed subframe mode, making it suitable for monitoring fast manufacturing processes.

The PI 640i works with Optris PIX Connect software, which is available as a free download with updates. The PIX Connect package comes with tools for identifying hot and cold spots, generating histograms, temperature profiling, image subtraction, and other thermal image processing features. For researchers and process engineers, the PC-based PIX Connect platform offers strong thermal image processing capabilities, enabling users to extract and document fully calibrated temperature measurements from any pixel in the scene. Time-versus-temperature data can be extracted from live thermal video feeds and recorded thermal video files that contain stored temperature data. Engineers can use the data collection features to find the highest, lowest, and average temperatures from areas of any size or shape, along with complex alarm signals. Additionally, the system allows replaying stored thermal video frame by frame, enabling engineers to capture and store radiometric images and take snapshots during temperature changes.

Many engineers gather data on multiple locations of electric devices over extended periods using the Temperature/Time feature, which logs data at user-defined intervals and saves it in .csv files. Some engineers prefer capturing full images and utilize calibrated sequence files or calibrated .tiff images, recorded at user-defined intervals. The Snapshot sequence storage routine also supports saving the complete temperature matrix in CSV format at user-defined intervals, providing detailed data for analysis.

Thermography software optris PIX Connect is included and license-free.All infrared cameras are delivered with the thermography software optris PIX Connect, developed specifically for the extensive documentation and analysis of thermal images. The Windows-based PIX Connect software enables users to tailor the infrared cameras to meet specific requirements. It analyses live and recorded temperature data and triggers alarm signals for process integration. The key to leveraging the Optris infrared camera is a correct configuration. This includes detailed device-specific configurations such as frame rate, measurement range adjustments, external communication settings, and USB/Ethernet configurations. Moreover, PIX Connect facilitates firmware updates and the download of configuration files over the Internet. PIX Connect Optris offers several different SDKs for our Xi and PI thermal imaging cameras. Depending on the operating platform, the infrared camera, the coding language, and the hardware platform, different software interfaces can be utilized: SDK The Optris IRmobile allows users to set up and commission an Optris infrared pyrometer or infrared camera with an Android smartphone or tablet. This tool becomes handy for commissioning and aligning the infrared camera’s field of view or adjusting the configuration. The app analyzes the connected infrared camera‘s live infrared image stream with auto hot and cold spot detection. For pyrometers, a temperature-time diagram or the video signal is displayed. This app works on most Android devices running 5.0+ with a USB port supporting USB-OTG (On The Go). Google Play

Can I switch between MO2X and MO44 optics?

Yes. Optics can be changed in the field and deliver calibrated temperature measurements, provided both optics are calibrated with the specific PI 640i they are mated with. For correct calibration, make sure to select the optic attached to the camera from the pull-down optics box in the Device tab of the Configuration menu. All optics that have been calibrated with your serial number camera will be visible in this box if the PC hosting PIX Connect software is online.

Can I use non-microscopic field-of-view optics for larger targets such as printed circuit boards?

Yes. Four additional optics are available for the PI 640i and can be calibrated for use with the camera. This dramatically extends the PI 640i’s application potential, enabling thermal imaging and temperature measurement of full-size printed circuit boards or the products that host them. As with microscope optics, make sure to select the correct calibration file when switching optics.

I have my microscope optics. Can I use these?

Microscope optics developed with visible light cameras will not transmit infrared radiation emitted in the spectral region where the PI 640i is responsive and cannot be used with an infrared camera. Infrared optics not calibrated with the PI 640i could potentially deliver magnified thermal images but will not deliver calibrated temperature measurements.

Why do I need a microscope stage?

Macro focus can be performed using the knurled ring on the outside of the microscope objective but minute adjustments in working distance can dramatically improve image clarity and temperature measurement accuracy. Each microscope package’s stages facilitate this minute working distance adjustment. If the image is not in optimal focus, the temperature measurements will not be accurate.

Can I measure the temperature of the leads connected to my small electronic devices?

Small leads can be seen with powerful infrared microscope optics but are most often made of low-emissivity metals that reflect heat energy. Leads need to be coated with carbon black or flat black paint to be accurately measured with an infrared camera. The same is true for a component (can) made from metal. If a metal lead cannot be treated with a high emissivity coating, the high emissivity connection point of the lead to a device can often serve as an indication that the lead in question is running hotter than desired.

Can I see through the layers on a printed circuit board?

FR-4 and Teflon (PTFE) are common materials used as substrate layers in printing circuit boards. They are not transmissive in the infrared region so you cannot see through them with an IR camera. However, heat from a specific region may conduct up through the various printed circuit board layers to the top board, presenting any conducted heat to an infrared camera targeted at that region on the board surface. The camera settings may need to be optimized to enhance sensitivity so that small shorts from inner layers can be seen. Copper foil inserted in between PCB layers can mute or entirely prevent the flow of heat from the inner layers to the top surface of the board.

Can an infrared camera validate chip and substrate temperatures during PCB manufacturing?

Any infrared measurement requires a clear line of sight between the camera optics and the surface to be measured. Infrared temperature measurements in a reflow oven would be impossible without an access port and mounting and camera cooling provisions. Although there is no system actively marketed now with this capability there is one forced-convection SMT reflow system in development using Optris IR cameras in line scan mode to measure temperatures and create full infrared images through small slits in the oven in four locations.

The stated accuracy in that range for the PI 640i LT is +-2 C, but I was wondering if the accuracy could be further improved with surface emissivity information or calibrated to +-1 C or better

No, the actual temperature accuracy could not be further improved by information on surface emissivity. This is for the PI640i camera ±2 °C or ±2 %.
However, accurate surface information regarding the emissivity is necessary in order to measure the correct temperature based on the reflection ratio on the surface to be measured. An incorrectly set emissivity results in a temperature deviation.

I have a PI 640i and would like to connect it with the USB cable. What do I do if I’m not receiving a signal in the software?

• Check in the WINDOWS device manager that the USB driver was recognized correctly
• Go to Settings/Camera or via search and type in „camera“ and then activate the button “allow apps to access your camera”. Due to an Windows Update this could happen.
• If you have a black screen on PIXConnect software, this could be because of the bad performance of your graphic chip and hardware acceleration. Regarding this case, reduce the screen resolution of the monitor.
• Check the USB cable and the connector pins on camera and PC side
• Try another USB port of the PC or another PC (if available) to check that the USB cable has no issue
• Maybe the USB power supply of the camera supporting PC is too low
• Using a too long USB cable / a not provided USB cable by Optris or an USB extension cable could be the reason that the software PIXConnect does not get any signal
• Use a PC where you have administrative rights or check with your local administrator

Will optris PIX Connect Software for optris IR Cameras run on my iPad?

No, PIXConnect currently cannot be run on an iOS system (Apple).

Is your infrared camera long-wave (LWIR) or short-wave (SWIR/MWIR)? What’s the typical frame rate? What’s the IFOV (instantaneous field of view / pixel size)? And does it connect to a PC via USB, or what other platforms/interfaces are supported (e.g., Ethernet, etc.)?

Optris provides different types of IR cameras with different wavelengths. Here you can find an overview of the different camera types regarding the spectral ranges, the typical frame rates and the interface versions (USB or Ethernet (ETH)):

Long-wave (LWIR) cameras (spectral range 8-14 µm):

• PI400i LT (80Hz, switchable to 27 Hz),
• PI450i LT (80Hz, switchable to 27 Hz),
• PI640i LT (32 Hz (640×120 px @ 125 Hz),
• Xi80 LT ETH (50 Hz),
• Xi400 LT USB (80Hz, switchable to 27 Hz),
• Xi410 LT ETH (25 Hz (connected via Ethernet,4 Hz connected via USB),
• Xi640 LT USB (32 Hz)

Long-wave (LWIR) cameras (spectral range 7,9 µm):

• PI450iG7 (80Hz, switchable to 27 Hz),
• PI640iG7 (32 Hz (640×120 px @ 125 Hz)

Middle-wave (MWIR) cameras (spectral range 3,9 µm):

• Xi320MT (30 Hz)

Short-wave (SWIR) cameras:

• PI1M (0,85-1,1µm), 32 Hz (382×268 px @ 80 Hz, (switchable to 27 Hz)/ 72×56 px/ 764×8 px @1 kHz)),
• PI08M (780-820 µm), 32 Hz (382×268 px @ 80 Hz, (switchable to 27 Hz)/ 72×56 px/ 764×8 px @1 kHz)) ,
• PI05M (500-540 µm), 764×480 px @ 32 Hz/ 382×288 px @ 80 Hz (switchable to 27 Hz)/ 72×56 px/ 764×8 px @ 1 kHz,
• Xi1M ETH (0,85-1,1µm), 396×300 px, 20 Hz, 396×8 px (auton.: 396×1 px), 500 Hz, 0,85-1,1 μm, Ethernet, USB 2.0 (only 20 Hz), Auton. operation,
• Xi05M ETH (500-540 µm), 396×300 px, 20 Hz, 396×8 px (auton.: 396×1 px), 500 Hz, 500-540 nm, Ethernet, USB 2.0 (only 20 Hz), Auton. operation

The following digital interface kits are for the Xi 80/ 410/ 05M/ 08M cameras available:

• Ethernet TCP/IP / Modbus TCP interface kit
• EtherNet/IP interface kit
• Profinet kit

You can see the IFOV (instantaneous field of view / pixel size) for your IR camera with the different available optics in the optics calculator on the Optris website: Optris IR Camera Calculator (https://optris.com/optris-calculator/camera/)
Example:

What is the bit depth of our camera?

The bit depth of our cameras is 14 bit. The data has 16 bit but only 14 bit are used for the Temperature Data and the other 2 bits are not used

Can we send the raw ADU data from the camera to another commercial software for processing?

As a rule, we do not disclose any information about raw data. The only option is to use the Connect SDK to output the camera’s ADU values as a matrix. However, these ADU values are uninterpreted. The cameras can send the temperature information and the color information to another commercial software for processing.

Does changing the mode from Temperature to ADU in the Connect SDK change the way that the image is displayed?

No, the way the image is displayed does not change. You can see this in the software examples provided with the PIXConnect software (See the menu HELP => Connect SDK => Examples). Under the configuration menu => External communication => ConnectSDK. You can change the mode from “Temperatures” to “ADU”. This has no influence on the displayed image.

Our company designs and supplies camera systems for steelmaking processes and is exploring different camera types. For this application, would you recommend long-range, near-infrared, or short-wave infrared models?

For steelmaking processes we recommend short-wave infrared cameras as the PI 1M camera, PI 08M camera, PI05M camera , Xi1M camera or Xi 05M camera. Use the lowest wavelength / spectral range as possible!

I’m using the SDK to run SimpleViewer on Linux and have PI Connect installed on Windows. After performing calibration, the thermal image appears entirely black and displays an incorrect temperature reading of 257°F. Which setup or calibration steps could I have overlooked to make this work correctly?

• Regaring the black display in the software PIXConnect , this could be caused by a bad performance of your graphic chip e.g. the hardware acceleration. Reduce the screen resolution of your monitor or if possible reduce the hardware acceleration
• Set the Optimization to “Performance” and remove the hook from “High Speed temperature calculation”

Does the PI 640i support external triggering? Specifically, can I connect a relay output or a controller’s digital output to trigger image acquisition on the camera?

• Yes , the PI 640i camera supports via the software PIXConnect external triggering to record an image.
• You can use an analog input or a digital input signal via the Process Interface (PIF) to trigger the camera.
• In the configuration menu, PIF setting menu , you can set the voltage signal for the analog signal to trigger the camera or you can set the edges conditions for the digital signal to trigger the camera.
• Another possibility to trigger a snapshot via a controller’s digital output is to use the serial communication (if available at the PLC). For this you can use the command list of the serial communication to send the command to take a snapshot.

Which Optris infrared cameras support integration with machine learning frameworks? Do they provide raw thermal image data access via SDK/API (e.g., the OTC SDK), allowing developers to apply custom ML models for tasks like segmentation, classification, or predictive thermal analysis?

The IR cameras do not provide any raw thermal image data access. You get the temperature data via the SDK (OTC SDK) from the camera to your process.

Which Optris infrared camera is best for measuring temperatures during welding processes?

• The choose of the correct Optris infrared camera depends on the temperature range and the type of the welding process.
• For plastic welding , a PI/Xi LT camera can be used (8-14 µm)
• For metal (e.g. steel applications) a short wavelength camera PI 1M/08M/05M , Xi 1M , Xi05M should be used (0.85-1.1 µm , 780-820 µm , 500-540 µm)
• For laser welding applications Optris provides IR cameras with a blocking filter.

• Infrared Camera PI 640i with Microscope optics
• USB cable (1m)
• Cable for output/input (1 m) incl. terminal block
• Rugged outdoor transport case (IP67)
• Microscope stand
• Base plate with ESD pad
• Software package optris PIX Connect
• Quick Start Guide