New American technology makes more powerful thermal cameras at a lower cost

Thermal imaging is a critical technology in the war in Ukraine, spotting warm targets such as vehicles and soldiers in the darkest of nights. The military-grade thermal cameras used in the large Baba Yaga night bombers are too expensive for drone manufacturers to assemble $400 kamikaze drones, which must rely on cheaper devices. But a new technology developed by US company Obsidian Sensors Inc could transform the thermal imaging market with affordable high-resolution sensors.

Thermal imaging for drones

While digital cameras have evolved rapidly since their introduction, thermal imaging has stagnated. This is because without a mass market, there is no incentive for manufacturers to invest in the next generation. The resulting difference in development is dramatic.

Apple’s Quicktake camera from 1994 offered 640×480-pixel resolution for $1,000. By 1999, Nikon’s Coolpix 800 gave six times the resolution and cost less. Now even a $10 kid’s camera boasts a much higher resolution.

Unlike Seek Thermal imaging device for consumers was released in 2015 with 206 x 156 pixel images for around $200. The same product is the market leader at the same price today. More powerful thermal imaging cameras — like this $8,000 military-grade system with 1,024×768 pixels — are sold in small quantities.

This makes it difficult to produce a cheap drone for night operations. A drone manufacturer passing by FPVDronesUA on Twitter/X and builds FPV for Ukraine and told me about the trade-off between cost and performance in the imagery they worked with, invariably from Chinese companies.

The minimum viable sensor is a 256×192 pixel image. This costs about $200, but produces a very grainy picture.

“The 256 gives you pretty poor image quality compared to the better thermals and is very dependent on weather factors like humidity, cloud cover and how cold it is outside,” FPVDronesUA told me. “The 256 is really hard to fly.”

The next level is 388 x 254 pixels, which is significantly better, but three times the price at around $600.

“They are less time-dependent because they capture more pixels, their spectral bandwidth and NETD are almost the same as 256,” says FPVDronesUA. “They are much more convenient to use on a drone.”

But its preferred sensor is 640 x 480 (VGA resolution), starting at $800 if bought in batches of 50 or more, but usually over $1,000 if bought individually.

“640 thermals are great, but very expensive,” says FPVDronesUA. “These are very comfortable thermals, very similar to what we see on the Mavic 3T [an industrial drone for thermal mapping]. Also, higher resolution thermals have a higher field of view.” This means that larger images provide a much wider view; it’s less like looking through a drinking straw and easier to pilot. “A 256 thermal in 9mm would be pretty narrow, while a 640 thermal in 9mm gives you more than twice the field of view.”

Ideally, the camera would have a higher resolution to spot targets (and obstacles) at greater distances and make piloting less challenging. A $15 FPV day cam has a resolution of 1280 x 960, four times that of VGA.

Adding an $800 imaging unit turns a $400 drone into a $1,200 drone, so it reduces the number of drones he can afford to build by a factor of three. This is extremely important in a conflict where drone manufacturers like FPVDronesUA are still funded by charitable donations, and the Russians, with more funding, initially released more FPVs with thermal imaging. And there is no question of including them as standard on all FPV, thermal imaging cameras are only for night attack drones.

New thermal imaging technology

Older digital cameras were based on CCDs (charge-coupled devices), the current generation uses more affordable CMOS image sensors that produce an electrical charge in response to light. Most thermal imaging cameras use a different technology: an array of microbolometers, tiny devices whose pixels absorb infrared energy and measure the resulting change in resistance. The conventional design precisely integrates the microbolometers and the circuits that read them on the same silicon chip.

Expanding this technology would be possible, but it would take a multi-billion dollar “factory” (a chip manufacturing plant), as happened with digital cameras. There is no incentive to invest such money,

John Hong, CEO of San Diego-based Obsidian Sensors, believes there is a better approach that can scale up to high resolution at low cost and, crucially, high volume, in established foundries. The new design does not integrate everything into one device, but separates the bolometer array from the readout circuits. This is more complicated, but allows a different manufacturing technique to be used.

The readout circuits are still on silicon, but the array of sensors is fabricated on a sheet of glass using technology perfected for flat-screen TVs and mobile phone displays. Large sheets of glass are much cheaper to process than small silicon wafers, and bolometers made on glass cost about a hundred times less than on silicon.

Hong says the process can easily produce multi-megapixel arrays. Obsidian is already producing test batches of VGA sensors and plans to move to 1280×1024 this year and 1920×1080 in 2025.

Obsidian has been quietly developing its technology for six years and is now able to produce evaluation units at three to four times the cost of comparable models. Further development of the production process will lead to even lower prices.

Cars and drones

Obsidian’s first target market is automotive safety and self-driving cars. Currently, they usually use LIDAR (laser radar) sensors to keep to the road and avoid accidents. But LIDAR cannot easily distinguish pedestrians from the background that thermal imaging cameras can.

Last month, the US National Highway Traffic Administration issued a new safety standard for automatic emergency braking for all new passenger cars from September 2029. This must automatically detect pedestrians and apply the brakes, and the requirement to operate in the dark will benefit of thermal imaging systems. Millions of new cars sold each year represent a huge potential market, and this week Obsidian announced a partnership with Quanta Computer Inc to produce thermal imaging cameras for cars

Delivery drones are another potential market. They are currently in small-scale trials, but large-scale operations are likely to require high-resolution thermal imaging cameras for safety, and again demand could run into the millions.

Ukraine, meanwhile, plans to build over two million drones this year and import another million, and their drone manufacturers have already expressed interest in the technology. Other nations are likely to follow suit, creating even greater demand for small, inexpensive thermal imaging cameras.

The future of thermal imaging

Hong says they plan to sell a thousand VGA cameras this year in a pilot production run and are currently assembling the B series to achieve much higher volumes in 2025 and beyond. That should be just about right for you to surf the search wave for the next few years.

A developing market will attract new suppliers. They will most likely be based in China and simply expand existing production techniques. But cost and scale advantages, as well as a desire for greater supply chain security, may favor the new approach to building sensors on glass in the US

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