Scientists adapt the astronomy method to blur microscopy images

A team led by researchers at HHMI’s Janelia Research Campus has adapted a class of techniques used in astronomy to defocus images of distant galaxies for use in the life sciences, giving biologists a faster and cheaper way to get clearer and sharper images. obtain microscopy images. The findings are published in the journal Optics.

Astronomers long ago discovered how to make the images their telescopes take of distant galaxies clearer and sharper. By using techniques that measure how light is distorted by the atmosphere, they can apply corrections to remove aberrations.

Microscopists have adapted these methods to generate clearer images of thick biological samples, which also bend light and cause distortions. But these techniques – a class of methods called adaptive optics – are complex, expensive and slow, putting them out of reach for many laboratories.

In hopes of making adaptive optics more widely available to biologists, a team led by researchers at HHMI’s Janelia Research Campus has turned their attention to a class of techniques called phase diversity, which is widely used in astronomy but new to the life sciences.

These phase diversity methods add additional images of known aberrations to a blurred image of unknown aberration, providing enough additional information to defocus the original image. Unlike many other adaptive optics techniques, phase diversity does not require major changes to an imaging system, making it a potentially attractive route for microscopy.

To implement the new method, the team first adapted the astronomy algorithm for use in microscopy and validated it with simulations. They then built a microscope with a deformable mirror, whose reflective surface can be changed, and two additional lenses: minor adjustments to an existing microscope that cause the well-known aberration. They also improved the software used to perform the phase diversity correction.

As a test of their new method, the team demonstrated that they could calibrate the microscope’s deformable mirror 100 times faster than competing methods. They then showed that the new method could detect and correct randomly generated aberrations, creating clearer images of fluorescent beads and fixed cells.

The next step is to test the method on real-world samples, including living cells and tissues, and extend its use to more complex microscopes. The team also hopes to make the method more automated and easier to use. They hope that the new method, which is faster and cheaper to implement than current techniques, could one day make adaptive optics accessible to more laboratories, allowing biologists to see better when looking deep into tissues.