New US technology enables more powerful thermal imaging cameras at lower costs

Thermal imaging cameras were a crucial technology in the war in Ukraine, allowing them to detect warm targets such as vehicles and soldiers even in the darkest night. Military-grade thermal imaging cameras used in large Baba Yaga night bombers are far too expensive for drone manufacturers who build $400 FPV kamikaze drones and have to resort to less expensive equipment. But a new technology from US company Obsidian Sensors Inc. could revolutionize the thermal imaging market with affordable high-resolution sensors.

Thermal imaging for drones

While digital cameras developed rapidly after their introduction, thermal imaging technology is in the doldrums. Without a mass market, there is no incentive for manufacturers to invest in the next generation. The resulting difference in development has been dramatic.

Apple’s 1994 Quicktake camera offered a resolution of 640 x 480 pixels for $1,000. In 1999, Nikon’s Coolpix 800 offered six times the resolution and cost less. Today, even a $10 children’s camera can boast much higher resolution.

In contrast, the Seek is thermal Imager for consumers was launched in 2015 with an image resolution of 206 x 156 pixels for around $200. The same product is the market leader today at the same price. More powerful thermal imaging cameras — like this $8,000 1,024-by-768-pixel military system — are sold in tiny numbers.

This makes it difficult to build a cost-effective drone for night operations. A drone builder passing by FPVDronesUA on Twitter/X and builds FPVs for Ukraine and told me about the price/performance trade-off with the imagers they’ve worked with, all from Chinese companies.

The minimum usable sensor is a 256×192 pixel image sensor. This one costs around $200 but produces a very grainy image.

“256 offers fairly poor image quality compared to better thermals and is highly dependent on weather factors such as humidity, cloudiness and cold,” FPVDronesUA told me. “256 is really hard to fly.”

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

“They are less dependent on weather 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.”

However, its preferred sensor is 640 x 480 (VGA resolution), and prices start at $800 when purchased in batches of 50 or more, but are typically well over $1,000 when purchased individually.

“640 thermal planes are great but very expensive,” says FPVDronesUA. “These are very comfortable thermal suits, very similar to the ones we see in the Mavic 3T [an industrial drone for thermal mapping]. Higher resolution thermography images also have a larger field of view.” This means that the larger imagers offer a much broader view; It’s less like looking through a straw and easier to control. “256 thermal with 9mm lens would be quite narrow, while 640 thermal with 9mm lens provides more than twice the field of view.”

Ideally, the imager would have a higher resolution to detect targets (and obstacles) at greater distances and make control less demanding. A $15 FPV daylight camera has a resolution of 1280 x 960, four times that of VGA.

Adding an $800 imager turns a $400 drone into a $1200 drone, so the number of drones he can afford is reduced by a factor of three. That’s extremely important in a conflict where drone manufacturers like FPVDronesUA are still funded by charitable donations, and the Russians, with more money, initially released more FPVs with thermal imaging cameras. And there’s no question of including them as standard on all FPVs, thermal imaging cameras are only intended for night attack drones.

New thermal imaging technology

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

Scaling this technology would be possible, but would require a multi-billion dollar “fab” (chip factory), as was the case 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 that can achieve high resolution in established foundries at low cost and, crucially, in high volume. The new design does not integrate everything into one unit, but rather separates the bolometer array from the readout circuitry. Although this is more complex, it allows the use of a different manufacturing technique.

The readout circuitry is still made of silicon, but the sensor array is fabricated on a glass plate. This uses technology that has been perfected for flat screen televisions and cell phone displays. Large sheets of glass are far cheaper to process than small silicon wafers, and bolometers made on glass cost about a hundred times less than those made on silicon.

According to Hong, this 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 quietly developed its technology for six years and is now able to produce test devices at a price three to four times lower than comparable models. Further development of the manufacturing process will reduce prices even further.

This means that the price for an imager with a 640 x 480 VGA sensor could be well under $200.

Cars and drones

Obsidian’s first target market is vehicle safety and self-driving cars. Currently, LIDAR (laser-based radar) sensors are typically used to control the roadway and prevent accidents. However, LIDAR sensors cannot distinguish pedestrians from the background as easily as thermal imaging cameras can.

Last month, the U.S. National Highway Traffic Administration issued a new safety standard for automatic emergency braking on all new passenger vehicles starting in September 2029. This must automatically detect pedestrians and apply the brakes, and the requirement to function in the dark will greatly favor 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 make thermal imaging cameras for cars.

Delivery drones are another potential market. These are currently at the small-scale trial stage, but large-scale deployments will likely require high-resolution thermal imaging cameras for security reasons, and again demand could be in the millions.

Meanwhile, Ukraine plans to build over two million drones and import a million more this year, and its drone manufacturers have already expressed interest in the technology. Other countries are likely to follow suit, driving even more demand for small, low-cost thermal imaging cameras.

The future of thermal imaging

Hong says they plan to sell a thousand VGA cameras this year as part of a pilot production run, and are currently launching a Series B to reach much larger volumes in 2025 and beyond. That should be just enough to ride the wave of demand for the next few years.

The emerging market will attract new providers. Many are likely to be based in China and are simply expanding existing production techniques. But the cost and scale advantages, as well as the desire for greater supply chain security, could favor the new approach of building sensors on glass in the US.