New American technology creates more powerful thermal cameras at a lower price

Thermal imaging was a key technology in the war in Ukraine, spotting warm targets like vehicles and soldiers in the darkest of nights. Military thermal cameras used on large Baba Yaga night bombers are too expensive for drone manufacturers who assemble $400 FPV kamikaze drones who must rely on cheaper devices. But 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 developed rapidly after their introduction, thermal imaging was stuck at a standstill. This is because without a mass market there is no incentive for manufacturers to invest in the next generation. The resulting difference in development was dramatic.

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

In contrast, Seek Thermal imager for consumers it was launched in 2015 with a 206 x 156 pixel image for around $200. The same product is the market leader today at the same price. More powerful thermal imaging cameras — like this $8,000 military system with 1,024×768 pixels — are sold in small quantities.

This makes it difficult to build a cheap drone for night operations. A passing drone manufacturer FPVDronesUA on Twitter/X and makes FPVs for the Ukraine and told me about the trade-off between price and performance in the imagers they worked with, always from Chinese companies.

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

“256 gives you pretty poor image quality, compared to better thermals and they are 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 Band and NETD are about the same as 256,” says FPVDronesUA. “These are much more comfortable to use on a drone.”

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

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

Ideally, the camera would have a higher resolution for spotting targets (and obstacles) at greater distances and for piloting to be less demanding. The $15 daylight FPV camera has a resolution of 1280 x 960, four times that of VGA.

Adding an $800 image capture device turns a $400 drone into a $1,200 drone, reducing the number of drones it 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 funds, initially fielded more FPVs with thermal imaging. And there is no question of including them as standard for all FPVs, thermal cameras are only for night attack drones.

New thermal imaging technology

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

Scaling up this technology would be possible, but would require a multi-billion dollar factory (a chip factory) as happened with digital cameras. There is no incentive to invest so much money,

John Hong, CEO of San Diego-based Obsidian Sensors, believes he has a better approach, which he can scale up to high resolution at low cost and, most importantly, in large volumes, at established foundries. The new design does not integrate everything into a single unit, but separates the bolometer array from the readout circuits. This is more complex, but allows the use of a different manufacturing technique.

The readout circuitry is still silicon, but the sensor array is fabricated on a glass plate, using technology perfected for flat-screen TVs and cell phone displays. Processing large glass sheets is far cheaper 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 their technology for six years and are now able to produce evaluation units at three to four times the price of comparable models. With further development of the production process, prices will be even lower.

That could drop a 640×480 VGA image sensor to well under $200.

Cars and Drones

Obsidian’s first target market is automotive safety and self-driving cars. Currently, they usually use LIDAR (laser radar) sensors to stay on the road and avoid accidents. But LIDAR cannot easily distinguish pedestrians from the background, which thermal 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 strongly favor thermal imaging systems . The millions of new cars sold each year represent a huge potential market and this week Obsidian announced a partnership with Quanta Computer Inc for makers of automotive thermal imaging cameras

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

Ukraine, meanwhile, plans to build more than 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 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 ramping up the B series to achieve much higher volumes in 2025 and beyond. That should be enough to surf the wave of demand for the next few years.

An emerging market will attract new suppliers. Many will likely be based in China and simply scale up existing production techniques. But the cost and scaling advantages and the desire for greater supply chain security may favor the new approach of building sensors on glass in the US.