We compare the iterative angular spectrum (IAS) and the optimal rotation angle (ORA) methods in designing two-dimensional finite aperture diffractive optical elements (FADOEs) used as beamfanners. The transfer functions of both methods are compared analytically in the spatial frequency domain. We have designed several structures of 1-to-4 and 1-to-6 beamfanners to investigate the differences in the performance of the beamfanners designed by ORA method for near field operation. Using the three-dimensional finite difference time-domain (3-D FDTD) method with perfect matched layer (PML) absorbing boundary condition (ABC), the diffraction efficiency is calculated for each designed FADOE and the corresponding values are compared.

Download full-text PDF

Source
http://dx.doi.org/10.1364/oe.17.014825DOI Listing

Publication Analysis

Top Keywords

iterative angular
8
angular spectrum
8
optimal rotation
8
rotation angle
8
methods designing
8
comparison iterative
4
spectrum optimal
4
angle methods
4
designing beam-fanners
4
beam-fanners compare
4

Similar Publications

Article Synopsis
  • PET imaging using Zr is gaining traction for visualizing immune and cancer cells, but has limitations due to low image quality from gamma ray emissions.
  • A new prototype has been developed to improve Compton imaging within PET by redesigning the scatter detector and optimizing image reconstruction methods.
  • The upgraded WGI system showed enhanced imaging performance, including improved angular resolution, sensitivity, and reduced noise, demonstrating successful in-vivo imaging of a mouse with tumor burden after Zr labeled antibody injection.
View Article and Find Full Text PDF

Prevalence of Complications Due to Transphyseal Hematogenous Osteomyelitis.

J Bone Joint Surg Am

December 2024

Pediatric Orthopaedic Unit, Pediatric Surgery Service, Geneva University Hospitals, Geneva, Switzerland.

Background: Transphyseal hematogenous osteomyelitis (THO) is a common infectious condition, being present in 25% of patients with hematogenous osteomyelitis. A large proportion of pediatric hematogenous osteomyelitis infections can spread through the growth cartilage and therefore may be potentially responsible for growth disorders, leading to limb-length discrepancy or angular deformities. The purpose of the present study was to identify both the prevalence of complications caused by transphyseal osteomyelitis and factors influencing their occurrence.

View Article and Find Full Text PDF

Ultrasound-assisted aberration correction of transcranial photoacoustic imaging based on angular spectrum theory.

Photoacoustics

December 2024

Ministry-of-Education Key Laboratory of Modern Acoustics, Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.

To correct the refraction aberration induced by the skull in photoacoustic imaging, a method for phase distortion compensation is proposed based on the angular spectrum theory with the aid of ultrasonic signals. This method first updates the speed of sound distribution by iteratively performing aberration correction in the ultrasonic reconstruction. Then the speed of sound distribution obtained with ultrasound-assisted serves as prior knowledge to address phase distortion compensation by adjusting the phase shift factor of the wavefront in different media.

View Article and Find Full Text PDF

To explore the impact of digital technology in constructing a three-dimensional (3D) symmetry reference plane (SRP) for esthetic restoration of anterior teeth and to evaluate its clinical applicability. A cross-sectional study was conducted from February to May 2024, involving 20 patients [11 males and 9 females, aged (36.8±11.

View Article and Find Full Text PDF

Light field imaging can simultaneously record spatial and angular information of light signals to provide various computational imaging functions. However, traditional microlens array-based light field cameras usually suffer from a trade-off between spatial and angular resolutions. In contrast, focal scanning light field imaging (FSLFI) can digitally modulate an incident light field through an image stack captured at different focal planes and then utilize the transport-of-intensity property to computationally recover the full-resolution light field.

View Article and Find Full Text PDF

Want 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!