Power contained in a square area of an image formed by a diffraction-limited imaging system with a centrally obscured circular pupil is calculated and compared with the power contained in a circular area. It is shown that, regardless of the amount of obscuration, the difference between the corresponding ensquared and encircled powers is less than 9% of the total image power. Approximate expressions are obtained for the power lying outside a large square or a circular area.

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.17.000964DOI Listing

Publication Analysis

Top Keywords

obscured circular
8
power contained
8
circular area
8
included power
4
power obscured
4
circular
4
circular pupils
4
power
4
pupils power
4
contained square
4

Similar Publications

Unidirectional Chiral Emission via Twisted Bi-layer Metasurfaces.

Nat Commun

November 2024

Science, Mathematics, and Technology (SMT), Singapore University of Technology and Design (SUTD), 8 Somapah Road, Singapore, 487372, Singapore.

Controlling and channeling light emissions from unpolarized quantum dots into specific directions with chiral polarization remains a key challenge in modern photonics. Stacked metasurface designs offer a potential compact solution for chirality and directionality engineering. However, experimental observations of directional chiral radiation from resonant metasurfaces with quantum emitters remain obscure.

View Article and Find Full Text PDF

Innovation in image-guided procedures has been driven by advances in robotic Cone Beam Computed Tomography (CBCT) systems. A fundamental challenge for CBCT imaging is metal artifacts arising from surgical tools and implanted hardware. Here, we outline how two universal non-circular imaging orbits, optimized for metal artifact reduction, can be implemented in real-time on clinical robotic CBCT systems.

View Article and Find Full Text PDF

Aim: Reconstruction of segmental bone defects with bone transport is a well-established treatment. Mechanical complications at the docking site after frame removal are common. These complications include malunion, non-union, axial deviation and refracture.

View Article and Find Full Text PDF

Objective: This study assessed the feasibility of smartphone-based colposcopy (SBC) for visual inspection of the cervix by community healthcare workers in low-resource areas.

Methods: This was a retrospective study conducted in community villages in rural Vietnam, where 177 participants were enrolled for a cervical cancer screening. Cervical images were obtained by pre-trained community healthcare workers using a portable, upcycled SBC (Samsung Galaxy Note 20).

View Article and Find Full Text PDF

Prostate cancer (PCa) belongs to a prevailing neoplasm globally. Circular RNAs (circRNAs) are critical regulators in various tumors, but the role of circRNAs in PCa is obscure. In this research, a circRNA derived from the TADA2A gene (hsa_circ_0006220) was high-expressed in PCa tissues along with cell lines.

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!