Breakthrough Fiber Probe Promises Sharper, Deeper Endoscopic Imaging
A new miniature fiber probe developed by researchers at the Beijing Institute of Technology is poised to revolutionize endoscopic imaging, offering significantly improved depth and resolution without increasing probe size. Published in Microsystems & Nanoengineering in July 2025, the innovation addresses long-standing limitations in visualizing internal tissues and structures, potentially leading to earlier and more accurate diagnoses.
Overcoming the Trade-Off in Endoscopic Imaging
Endoscopic optical coherence tomography (OCT) is a powerful tool for real-time visualization of tissue microstructures, but current probes present significant challenges. Traditional designs struggle within narrow spaces, risking tissue damage, and have historically faced a fundamental trade-off: increasing image sharpness reduces imaging depth, while extending depth blurs fine details. These constraints have limited the clinical utility of endoscopic imaging, particularly for early detection in confined organs. Manufacturing complexities have also hindered the development of smaller, more robust probes.
“There is a strong need to develop new side-viewing probes that deliver deep, sharp imaging without increasing size or complexity,” researchers noted.
A Redesigned Approach to Light Delivery
The new probe overcomes these hurdles with a redesigned light-delivery strategy. Instead of focusing light into a single, rapidly dispersing point, the probe maintains a narrow beam over a longer distance. This allows for clearer images across a much larger depth range. Testing with both linear and rotational scanning confirmed the probe’s effectiveness in biological tissues and narrow-lumen samples, suggesting a viable path toward safer and more informative endoscopic imaging in both clinical and industrial settings.
Impressive Performance Metrics
Experiments demonstrated an imaging depth of approximately 350 micrometers – more than ten times deeper than many conventional fiber probes – while maintaining a lateral resolution of around 1.4 micrometers. This means that intricate structures remain visible even at greater depths within the tissue. Crucially, this performance is achieved within a probe measuring just under one millimeter in diameter, making it suitable for navigating narrow anatomical passages. The researchers also confirmed stable imaging quality during rotational scanning, a critical feature for three-dimensional endoscopic imaging.
The probe’s capabilities were successfully demonstrated on layered materials, plant tissues, and animal tissues, proving that extended depth and high resolution are no longer mutually exclusive.
Scalability and Real-World Applications
“This work shows that we can rethink the limits of miniature endoscopic imaging,” said the study’s corresponding author. “By keeping the beam focused over a longer range, we can see deeper while preserving fine detail. Just as importantly, the probe is built using standard fiber-processing techniques, which makes it realistic to scale and deploy.”
The potential applications of this technology are broad. In medicine, the new fiber probe could significantly improve visualization of airways, gastrointestinal tracts, and pediatric organs, facilitating earlier diagnoses and minimizing tissue disturbance. Beyond healthcare, the probe could be adapted for non-destructive inspection of industrial components, layered materials, and the detection of micro-scale defects. Its compact size, low cost, and compatibility with existing manufacturing processes offer a realistic pathway from laboratory research to practical devices.
Ultimately, the study underscores the transformative potential of smarter light control in redefining the capabilities of miniature imaging systems.
Source: Chinese Academy of Sciences
Journal reference: Liu, Y., et al. (2025). Side-viewing axicon-integrated miniature fiber probe for extended depth of focus and ultrahigh lateral resolution endoscopic imaging. Microsystems & Nanoengineering. doi:10.1038/s41378-025-01034-x. https://www.nature.com/articles/s41378-025-01034-x.
