Low-Cost Lightweight Hyperspectral Imagers Bring Sophisticated Imaging Capability to Drones

Do it yourself hyperspectral imager for handheld to airborne operations. (source: The Optical Society)

Researchers used 3D printing to make the holder (black rectangular piece) for the optics used to create an inexpensive and small hyperspectral imager. Feasibility tests showed that 3D printing can be used to produce prototype parts that are accurate enough for optical systems. (source: The Optical Society)

June 18, 2018 | Source: The Optical Society, osa.org, 28 Feb 2018, OSA Media Relations

In a new study, researchers used 3D printing and low-cost parts to create an inexpensive hyperspectral imager that is light enough to use onboard drones. They offer a recipe for creating these imagers, which could make the traditionally expensive analytical technique more widely accessible.

Hyperspectral imagers produce images like a traditional color camera but detect several hundred colors instead of the three detected by normal cameras. Each pixel of a hyperspectral image contains information covering the entire visible spectrum, providing data that can be used, for example, to automatically detect and sort objects or measure ocean color to map harmful algae blooms. Traditional hyperspectral imagers can cost tens of thousands of dollars and are very bulky and heavy.

In The Optical Society (OSA) journal Optics Express, the researchers detail how to make visible-wavelength hyperspectral imagers weighing less than half a pound for as little $700 (USD). They also demonstrate that these imagers can acquire spectral data from aboard a drone.

“The instruments we made can be used very effectively on a drone or unmanned vehicle to acquire spectral images,” said research team leader Fred Sigernes of University Centre in Svalbard (UNIS), Norway. “This means that hyperspectral imaging could be used to map large areas of terrain, for example, without the need to hire a plane or helicopter to carry an expensive and large instrument.”

Although the new imagers don’t provide the sensitivity of traditional hyperspectral imagers, their performance is sufficient for mapping terrain or detecting ocean color in daylight. The researchers are now working to improve sensitivity by making slightly larger versions of the instruments that would still be small and light enough for use on drones. Improving the sensitivity of the imagers will provide higher quality data.