Periodic Reporting for period 1 - MultiPhase (Multimodal quantitative phase microscopy)
Período documentado: 2022-11-01 hasta 2024-04-30
Quantitative phase microscopies (QPMs), that are microscopy techniques capable of mapping the phase of light, have been increasingly used in biology this last decade, and more recently for applications in nanophotonics by the principal investigator (PI). They represent a powerful strategy to non-invasively characterize micro and nanoscale systems, and are complementary to more conventional fluorescence-based techniques in biology.
In particular, quadriwave lateral shearing interferometry (QLSI) is a wavefront sensing technique that can be used as a high-resolution, highly sensitive QPM technique. It is based on the association of a camera sensor, and a 2-dimensional (2D) diffraction grating, separated by a millimetrer distance from each other.
Problem 1:
QPMs do not capture the whole information a light beam can contain, in terms of wavelength and polarization, as they are usually based on a monochromatic, scalar description of the electromagnetic field. Moreover, for some samples, this assumption can yield misleading measurements, or data that are difficult to interpret.
Problem 2:
QPMs and fluorescence microscopy techniques can give complementary information, especially in biology. Unfortunately, implementing fluorescence and phase microscopy in parallel on the same microscope is cumbersome: Multimodal phase/fluo correlation microscopy normally requires two camera sensors, which complexifies the setup and the image registration. To fix this problem, a single sensor can be used, with different optical filters that can be flipped. However, in this case, phase and fluorescence images cannot be acquired at the exact same time, preventing the study of dynamic systems.
Solution:
The project aimed to solve both these problems at once with a single ground-breaking innovation: coupling QLSI systems with more advanced camera sensors, sensitive to wavelength or polarisation. This multimodal QLSI (multiQLSI) approach provides 4 different phase images from a single camera acquisition. Depending on the camera sensor, these 4 images provide either (i) the missing polarization information, or (ii) phase images at various wavelengths. The former implementation, polar-QLSI, is intended to map the vectorial electromagnetic field at the sample plane (intensity and two phase profiles along x and y), no longer an approximated scalar field. The latter imaging mode, colour-QLSI, is intended to (i) achieve coloured phase microscopy, a valuable concept for dispersive samples, or for the study of Mie or plasmon resonances in nanophotonics, and also (ii) to perform phase/fluorescence correlation microscopy in biology, in parallel, with the same camera sensor, a new paradigm.
In particular, quadriwave lateral shearing interferometry (QLSI) is a wavefront sensing technique that can be used as a high-resolution, highly sensitive QPM technique. It is based on the association of a camera sensor, and a 2-dimensional (2D) diffraction grating, separated by a millimetrer distance from each other.
Problem 1:
QPMs do not capture the whole information a light beam can contain, in terms of wavelength and polarization, as they are usually based on a monochromatic, scalar description of the electromagnetic field. Moreover, for some samples, this assumption can yield misleading measurements, or data that are difficult to interpret.
Problem 2:
QPMs and fluorescence microscopy techniques can give complementary information, especially in biology. Unfortunately, implementing fluorescence and phase microscopy in parallel on the same microscope is cumbersome: Multimodal phase/fluo correlation microscopy normally requires two camera sensors, which complexifies the setup and the image registration. To fix this problem, a single sensor can be used, with different optical filters that can be flipped. However, in this case, phase and fluorescence images cannot be acquired at the exact same time, preventing the study of dynamic systems.
Solution:
The project aimed to solve both these problems at once with a single ground-breaking innovation: coupling QLSI systems with more advanced camera sensors, sensitive to wavelength or polarisation. This multimodal QLSI (multiQLSI) approach provides 4 different phase images from a single camera acquisition. Depending on the camera sensor, these 4 images provide either (i) the missing polarization information, or (ii) phase images at various wavelengths. The former implementation, polar-QLSI, is intended to map the vectorial electromagnetic field at the sample plane (intensity and two phase profiles along x and y), no longer an approximated scalar field. The latter imaging mode, colour-QLSI, is intended to (i) achieve coloured phase microscopy, a valuable concept for dispersive samples, or for the study of Mie or plasmon resonances in nanophotonics, and also (ii) to perform phase/fluorescence correlation microscopy in biology, in parallel, with the same camera sensor, a new paradigm.
The colour-QLSI modality has been successfully demonstrated, in the context of biological applications. We have been able to build a working prototype, and acquire phase and fluorescence images from single camera acquisitions of living cells in culture. The device, the processing algorithm and illustrating results have been described in an article published in January 2024 [10.1038/s41598-024-52510-9].
Successful experiments have also been conducted on the other modality, the polar-QLSI system: a prototype was constructed and data have been acquired and successfully processed with a custom algorithm. We expect the submission of the related article in June 2024.
Successful experiments have also been conducted on the other modality, the polar-QLSI system: a prototype was constructed and data have been acquired and successfully processed with a custom algorithm. We expect the submission of the related article in June 2024.
The color-QLSI modality was demonstrated in the context of biology applications, but future research activities will demonstrate applications in nanophotonics.
Following the publication of our article [Sci. Rep. 14, 2142( 2024)], SILIOS, the company from whom we purchased the color camera in the ERC PoC MultiPhase project, showed an interest in our work, and expressed a wish to start discussions about marketing a color-QLSI product. SILIOS is an expert in the fabrication of 2D-gratings and their implementation on camera sensors, and therefore appears to be the ideal company to develop this product. Silios has therefore been identified as a potential future operator, subject to the conclusion of a license agreement with CNRS.
Following the publication of our article [Sci. Rep. 14, 2142( 2024)], SILIOS, the company from whom we purchased the color camera in the ERC PoC MultiPhase project, showed an interest in our work, and expressed a wish to start discussions about marketing a color-QLSI product. SILIOS is an expert in the fabrication of 2D-gratings and their implementation on camera sensors, and therefore appears to be the ideal company to develop this product. Silios has therefore been identified as a potential future operator, subject to the conclusion of a license agreement with CNRS.