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Near infrared and infrared multi-photon imaging through or inside bone is an emerging field that promises to help answer many biological questions that require minimally invasive intravital imaging. Neuroscience researchers especially have begun to take advantage of long wavelength imaging to overcome multiple scattering and image deep inside the brain through intact or partially intact bone. Since the murine model is used in many biological experiments, here we investigate the optical aberrations caused by mouse cranial bone, and their effects on light propagation. We previously developed a ray tracing model that uses second harmonic generation in collagen fibers of bone to estimate the refractive index structure of the sample. This technique is able to rapidly provide initial information for a closed loop adaptive optics system. However, the ray tracing method does not account for refraction or scattering. Here, we extend our work to investigate the wavefront aberrations in bone using a full electromagnetic model. We used Finite-Difference Time-Domain modeling of light propagation in refractive index bone datasets acquired with second harmonic generation imaging. In this paper we show modeled wavefront phase from different originating points across the field of view.
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Temporal and spectral multiplexing for EUV multibeam ptychography with a high harmonic light source
We demonstrate temporally multiplexed multibeam ptychography implemented for the first time in the EUV, by using a high harmonic based light source. This allows for simultaneous imaging of different sample areas, or of the same area at different times or incidence angles. Furthermore, we show that this technique is compatible with wavelength multiplexing for multibeam spectroscopic imaging, taking full advantage of the temporal and spectral characteristics of high harmonic light sources. This technique enables increased data throughput using a simple experimental implementation and with high photon efficiency.
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- Award ID(s):
- 1734006
- PAR ID:
- 10531112
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 30
- Issue:
- 17
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 30331
- Size(s):
- Article No. 30331
- Sponsoring Org:
- National Science Foundation
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