The team from the University of Aberdeen is working on the new technology with the Ministry of Defence's science and technology laboratory (DSTL).
The portable ultrasound scanner will use new brain scanning software.
The technology is still at an early stage of development but has already been trialled on real hospital patients to test its viability, the University of Aberdeen said in a statement.
The device - much smaller than an MRI scanner - would create a 3D model of the brain on location and it could then be used for swift diagnosis.
Researchers working on the project said soldiers with unseen head injuries could be overlooked in battlefield situations.
They said internal bleeding or other damage caused to the head by explosions or knocks, can cause death or have severe long-term implications. If identified early enough, emergency steps can be taken to prevent long-term damage, including drilling holes in the skull to relieve pressure, or taking medication.
Even minor head injuries that do not receive early treatment can result in complex long-term complications including depression, memory problems, attention deficit and other mental health issues, the scientists said.
"Traumatic brain injury is a big problem for the military, especially because it can be difficult to spot in the field and if left untreated, it can have long-term effects.
"Ultrasound is not normally used for imaging the brain, but we hope to prove through further investigations that it is a viable method of making an early diagnosis of head injury whilst in the field."
"Battlefield medics will not have CT or MRI scanners which are bulky and expensive, but they are likely to have ultrasound equipment already, so it is a case of extending the use of the kit they already have," she added.
