Researchers at the University of Connecticut have developed a lensless microscope that allows an observer to enjoy an enormous field of view. Instead of a lens, the system relies on a diffuser that lies between the object being imaged and the camera sensor. This novel technology could greatly help clinicians to assess diagnostic tissue samples by letting them view two entire slides at once.
Conventional microscopes allow an observer to view a very small portion of a slide at a time. This makes assessing tissue samples to diagnose disease cumbersome and time consuming. The field of view for light microscopes is typically only 1-2 millimeters, whereas tissue samples can frequently be several centimeters across.
To address this, these researchers set out to develop a new microscopy technique that allows for a dramatically increased field of view. It involves illuminating a specimen with a focused beam of light, and then using a diffuser between the specimen and the camera sensor, rather than a lens. While the sensor acquires images, the diffuser moves around the specimen randomly, and the system later reconstructs a final image from the obtained information.
“This approach cuts down on processing time, cost, and allows for a more complete image to be produced of the sample,” said Guoan Zheng, a researcher involved in the study. “Imagine being able to read a whole book at once instead of just a page at a time. That’s essentially what we hope our technology will allow clinicians to do.”
The team’s technology boasts a 30 mm2 field of view, permitting clinicians to analyze two full tissue slides simultaneously. Interestingly, using this system, samples do not need to be stained before analysis in order to spot features such as the nucleus. In fact, the researchers have developed the technique so that features such as nuclei can be automatically identified and counted.
“By using our lensless, turnkey imaging system, we can bypass the physical limitations of optics and acquire high-resolution quantitative information for on-chip microscopy,” said Zheng. “We’re excited to continue to refine this technology for commercial and clinical applications to have a tangible impact for patients and researchers.”
Study in Lab on a Chip: Wide-field, high-resolution lensless on-chip microscopy via near-field blind ptychographic modulation