Modern thermal imaging technology is fundamentally changing hunting optics and riflescope construction
For over two centuries, the principles of detecting infrared radiation have been understood. From William Herschel’s discovery of infrared in 1800 to Samuel Langley’s bolometer in 1880, the foundation for modern thermal imaging was laid. However, the true revolution – the creation of portable, uncooled, and mechanically simple thermal sensors – didn’t arrive until the turn of the 21st century. This breakthrough has fundamentally altered the landscape of hunting optics, driving innovation in riflescope construction and beyond.
Thermal imaging operates on a different part of the electromagnetic spectrum than visible light. Humans perceive light wavelengths between approximately 400 and 780 nanometers, allowing us to see colors and shapes. Thermal imaging, however, detects infrared radiation – wavelengths beyond the red end of the visible spectrum, typically in the mid- to long-wave range of 3.5 to 15 micrometers. This radiation is emitted by objects based on their temperature. A thermal sensor measures this emitted radiation, converts it into an electrical signal, and displays it as an image, effectively allowing users to “see” heat signatures even in complete darkness or through obscuring conditions like fog or smoke.
This futuristic Osprey multispectral binocular from Pard combines three optical channels in one device – thermal imaging, daylight, night vision and picture-in-picture – for flexible wildlife observation and an example of what is technically possible.
The modern devices available go far beyond simple heat detection. Manufacturers are integrating multiple functionalities into single units. The Hikmicro Habrok 4K HX60L, for example, combines thermal imaging, night vision, daytime binocular viewing (via a display), a rangefinder, and video recording capabilities into a handheld device resembling traditional binoculars. Such multifunctionality represents a significant leap in optical technology.
Selecting the right thermal sensor requires understanding specific technical specifications. Sensors are defined by their resolution, measured in pixels (e.g., 320×240, 640×480). Pixel pitch, measured in micrometers (µm), is also crucial; a lower pitch generally indicates better image quality. For 640×480 sensors, a pitch of 12 µm is considered a good benchmark. Sensitivity, expressed in millikelvin (mK) or NETD (Noise Equivalent Temperature Difference), determines the sensor’s ability to detect subtle temperature differences – lower values indicate higher contrast and clarity. Finally, the refresh rate, measured in Hertz (Hz), impacts the smoothness of the image, with 25Hz or 50Hz being preferable for live viewing and minimizing image blur.
The night vision channel in the Hikmicro Habrok 4K HX60L shows a sow with young boar at a distance of 71 metres – the handheld device, which only resembles binoculars on the outside, combines five functions: thermal imaging or night vision, daytime binoculars (via display), rangefinder and video recording. The price: just under 6,000 euros.
The integration of thermal technology into hunting optics isn’t without debate. A recent survey in Idaho revealed that a significant portion of big-game hunters would support a ban on both drones and thermal imaging devices, despite generally accepting other technological advancements in hunting. This highlights the ethical concerns surrounding fair chase and the potential for technology to provide an undue advantage. The discussion, as reported by the Chattanooga Times Free Press, underscores the need for ongoing dialogue about the responsible use of these powerful tools.
American Technologies Network (ATN) Corp recently announced the shipment of its fifth-generation series of smart HD thermal rifle scopes, signaling continued investment and innovation in this space. As technology continues to advance, You can expect to see even more sophisticated thermal imaging solutions emerge, further blurring the lines between traditional optics and cutting-edge sensor technology. The future of hunting optics is undeniably thermal, but its ultimate impact will depend on how these technologies are regulated and ethically employed.
