Traditional slit-based spectrometers have an inherent trade-off between spectral resolution and throughput that can limit their performance when measuring diffuse sources such as light returned from highly scattering biological tissue. Recently, multielement fiber bundles have been used to effectively measure diffuse sources, e.g., in the field of spatially offset Raman spectroscopy, by remapping the source (or some region of the source) into a slit shape for delivery to the spectrometer. Another approach is to change the nature of the instrument by using a coded entrance aperture, which can increase throughput without sacrificing spectral resolution.In this study, two spectrometers, one with a slit-based entrance aperture and the other with a coded aperture, were used to measure Raman spectra of an analyte as a function of the optical properties of an overlying scattering medium. Power-law fits reveal that the analyte signal is approximately proportional to the number of transport mean free paths of the scattering medium raised to a power of -0.47 (coded aperture instrument) or -1.09 (slit-based instrument). These results demonstrate that the attenuation in signal intensity is more pronounced for the slit-based instrument and highlight the scattering regimes where coded aperture instruments can provide an advantage over traditional slit-based spectrometers.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4221093 | PMC |
| http://dx.doi.org/10.1117/1.JBO.19.11.117001 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Revolutionizing Free-Space Optics: A Survey of Enabling Technologies, Challenges, Trends, and Prospects of Beyond 5G Free-Space Optical (FSO) Communication Systems.
Sensors (Basel)
December 2024
Instituto de Telecomunicações, University of Aveiro, 3810-193 Aveiro, Portugal.
As the demand for high-speed, low-latency communication continues to grow, free-space optical (FSO) communication has gained prominence as a promising solution for supporting the next generation of wireless networks, especially in the context of the 5G and beyond era. It offers high-speed, low-latency data transmission over long distances without the need for a physical infrastructure. However, the deployment of FSO systems faces significant challenges, such as atmospheric turbulence, weather-induced signal degradation, and alignment issues, all of which can impair performance.
View Article and Find Full Text PDFA gamma-ray imaging method for multiple radionuclides and low-activity radioactive sources.
J Environ Radioact
December 2024
Research & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen, 518063, China. Electronic address:
Gamma-ray coded-aperture imaging technology has important applications in the fields of nuclear security, isolated source detection, and the decommissioning of nuclear facilities. However, artifacts can reduce the quality of reconstructed images and affect the identification of the intensity and location of radioactive sources. In this paper, a gamma-ray coded-aperture imaging method based on primitive and reversed coded functions (PRCF) was proposed to reduce imaging artifacts.
View Article and Find Full Text PDFMultichannel full-space coding metasurface with linearly-circularly-polarized wavefront manipulation.
Nanophotonics
September 2024
Air and Missile Defense College, Air Force Engineering University, Xi'an 710051, China.
Achieving independent multitasked wavefront control by using an ultrathin plate is a challenge to increase information capacity in integration optics and radar applications. Transmission-reflection-integrated metasurface provides an efficient recipe primarily for multifunctional meta-device, however it is challenging to synergize both linear polarization (LP) and circular polarization (CP) using a single meta-plate. Here, a multichannel full-space coding metasurface composed of interleaved shared-aperture meta-atom is proposed to achieve large information capacity by capsulating judiciously engineered high efficiency triple sub-elements (modes) in four-layer scheme.
View Article and Find Full Text PDFAn ingenious and compact snapshot multispectral polarization imaging method is proposed based on a new, to the best of our knowledge, three-channel-switchable spectral polarization coded aperture. We utilize the coded aperture to simultaneously select three-channel light components and encode them with specific spectrum-polarization coefficients. It enables easy retrieval of each channel's light component from the mixed information via polarization measurements and linear decoding operations.
View Article and Find Full Text PDFThe point spread function (PSF) of an optical system could characterize the resolving ability of the whole optical system for point light sources. Therefore, the imaging performance of the system could be significantly improved by regulating and optimizing the PSF. In this paper, we innovatively propose a single-exposure hologram resolution enhanced cross-correlation (RECC) method for Interferenceless coded aperture holography(I-COACH) system, circumventing the necessity to obtain the point spread hologram (PSH) of an ideal point object.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!