SWIR Camera FAQ: Technology, Applications & Selection
Answers to common questions about InGaAs SWIR cameras, sensor performance, lenses, illumination, industrial applications, and choosing the right camera for your project.
SWIR fundamentals
What is SWIR imaging?
SWIR imaging records wavelengths beyond visible light. Standard InGaAs cameras commonly operate around 900–1700 nm; extended-SWIR cameras may reach 2500 nm. Images typically show reflected or transmitted light, not the long-wave thermal emission measured by LWIR cameras.
What can SWIR reveal that visible cameras miss?
Depending on wavelength and illumination, SWIR can reveal subsurface silicon features, moisture contrast, differences between polymers or coatings, and infrared laser spots. Material thickness and absorption determine what is visible.
How is SWIR different from NIR and thermal imaging?
Silicon cameras detect some near-infrared light but lose sensitivity around 1000–1100 nm. InGaAs extends response into SWIR. LWIR thermal cameras measure thermal emission and are preferable for routine temperature imaging.
Can SWIR see through fog, smoke or glass?
Sometimes SWIR improves visibility through haze, but it depends on atmospheric conditions. Many glasses transmit part of the SWIR band, although lens coatings, focus and wavelength still matter.
Is SWIR safe?
A camera is a passive detector. Any illumination source, especially an invisible SWIR laser, must be assessed separately for eye and skin safety.
Choosing a SWIR camera
What resolutions are available?
Pembroke’s described portfolio includes 320 × 256, 640 × 512, 1280 × 1024 and 1920 × 1080 area sensors and 2048-pixel LiSa line-scan cameras. Confirm pixel pitch, cooling, interface and speed for each model.
How do I choose resolution?
Define the smallest feature and total field of view. Object-space sampling is approximately field of view divided by pixels. Allow several pixels across critical defects and account for lens sharpness and illumination contrast.
When do I need extended SWIR?
Choose it when the target’s absorption or emission requires wavelengths beyond approximately 1700 nm. Longer wavelengths may require different lenses, lighting and deeper cooling.
What is the advantage of sensor cooling?
Cooling can reduce dark-current noise and stabilize response, particularly for long exposures and low-light imaging. Bright, short-exposure machine vision may need less cooling.
How fast can SWIR cameras run?
Speed is model-specific. For example, NIT specifies greater than 260 fps for WiDy SenS 640 G-STE2 and greater than 820 fps for 320 G-STE2. ROI may raise achievable frame rates. These figures are not specifications for every 640 or 320 camera.
What does wide dynamic range mean?
It helps capture bright and dark features in the same scene. G-STE2 specifies 120 dB typical in logarithmic mode versus 49 or 63 dB typical in particular linear modes; different modes have different noise and linearity behavior.
When should I use line scan instead of area scan?
Use area scan for a full image at once. Use line scan for continuously moving conveyors, films, webs and stages; synchronized motion builds a two-dimensional image.
Which SWIR camera suits semiconductor inspection?
Specify silicon thickness, defect size, wavelength, field of view, working distance and inspection speed. High-resolution sensors and SWIR microscope optics are often useful, but test contrast on real samples.
Optics, illumination and applications
Does SWIR need special illumination?
The scene must contain the wavelengths the camera detects. Sunlight and halogen lamps provide SWIR; many visible LEDs do not. Dedicated SWIR LEDs or broadband sources offer repeatability.
Can I use a visible-light lens?
Possibly, if it transmits the selected wavelength and has adequate sharpness. SWIR-rated lenses are generally preferable because coatings, aberrations and focus shift can limit visible-only optics.
How do I calculate field of view?
For a non-macro approximation, FOV ≈ sensor dimension × working distance / focal length. For close-focus setups, use actual magnification or manufacturer working-distance/FOV data.
Can filters improve moisture or material detection?
Yes. Narrowband illumination or filters can isolate spectral contrast; water-related contrast near 1450 nm is a common example. Robust chemical identification may require multiple bands or hyperspectral imaging.
What applications use SWIR?
Semiconductor and solar-cell inspection, industrial machine vision, laser beam profiling, material sorting, packaging, moisture detection, microscopy, research and continuous-web inspection.
Can SWIR cameras image 1064, 1310 and 1550 nm lasers?
Many standard InGaAs cameras can detect these wavelengths. Use safe attenuation and beam handling; never expose a camera directly to an unassessed high-power laser.
What is NUC?
Non-uniformity correction compensates for differences between pixels. Bad-pixel replacement handles known defective pixels. Correct calibration and thermal stability help produce clean images.
Software and purchasing
What software comes with the camera?
Depending on model, NIT offers NITVision, WiDyCAM, NITLink or NITGenicamControlTool. SDK and GenICam support differ by interface and generation. Consult the separate Engineering FAQ.
Can the cameras be externally triggered?
Many can, but electrical standards and timing are model-specific. The G-STE2 datasheet documents internal, external LVTTL and software trigger modes.
Are OEM options available?
NIT lists possible open-frame, windowless-sensor and split-board G-STE2 variants. Availability and drawings should be confirmed for each proposed order.
What information is needed for a recommendation?
Provide target material, wavelength, minimum feature, field of view, working distance, motion speed, lighting, host interface, environment and software requirements.
Are export restrictions possible?
Yes. Classification and licensing depend on the exact product, destination and end use. Do not assume all SWIR cameras have the same export status.
Need help selecting a SWIR camera?
Tell us your material, wavelength, field of view, working distance, smallest feature, speed, and software requirements. Pembroke Instruments can help narrow down the camera, optics and illumination options.
Technical basis: NIT Quick Start Guide rev. 2.0 (2025), WiDy SenS 320/640 G-STE2 datasheet v1.0 (2025), and Pembroke camera FAQ. Specific G-STE2 values do not apply to all models.