New Femto-Camera with Quadrillion Fractions of a Second Resolution

Researchers from ITMO University have built a setup for recording holograms of tiny objects like living cells with a femtosecond speed. The new method allows one to reconstruct phase topography of a studied sample according to deformations that emerge in a laser pulse when it passes through the specimen. In comparison to electron microscopes, the device can visualize transparent biological structures without introducing contrast agents. The paper was published in Applied Physics Letters. Vital activity of living cells is a complex sequence of biochemical reactions and physical processes; many of them take place with high temporal resolution. To register such rapid transformations, scientists need very accurate and much faster equipment. Biological tissue can be studied with an electron microscope, but this method requires introducing a special dye in the sample. The dye makes cells contrast, although it may affect their metabolism. Digital holographic microscopes can cope with this drawback, but have low spatial resolution. The new camera created by ITMO scientists can register fast processes in transparent specimens and allows one to increase the resolution of images in a wide range. The device records phase deformations of ultrashort, or femtosecond, laser pulses, that emerge when the light passes through the studied sample. The phase images, or holograms, will help explore cells for better understanding mechanisms of autoimmune, oncological, neurodegenerative diseases, as well as monitoring cells during surgical interventions like, for example, cancer therapy.”