skip to main content
Visitante
Meu Espaço
Minha Conta
Sair
Identificação
This feature requires javascript
Tags
Revistas Eletrônicas (eJournals)
Livros Eletrônicos (eBooks)
Bases de Dados
Bibliotecas USP
Ajuda
Ajuda
Idioma:
Inglês
Espanhol
Português
This feature required javascript
This feature requires javascript
Primo Search
Busca Geral
Busca Geral
Acervo Físico
Acervo Físico
Produção Intelectual da USP
Produção USP
Search For:
Clear Search Box
Search in:
Busca Geral
Or select another collection:
Search in:
Busca Geral
Busca Avançada
Busca por Índices
This feature requires javascript
This feature requires javascript
Coherence factor of speckle from a multi-row probe
Hollman, K.W. ; Rigby, K.W. ; O'Donnell, M.
1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027), 1999, Vol.2, p.1257-1260 vol.2
IEEE
Texto completo disponível
Citações
Citado por
Exibir Online
Detalhes
Resenhas & Tags
Mais Opções
Nº de Citações
This feature requires javascript
Enviar para
Adicionar ao Meu Espaço
Remover do Meu Espaço
E-mail (máximo 30 registros por vez)
Imprimir
Link permanente
Referência
EasyBib
EndNote
RefWorks
del.icio.us
Exportar RIS
Exportar BibTeX
This feature requires javascript
Título:
Coherence factor of speckle from a multi-row probe
Autor:
Hollman, K.W.
;
Rigby, K.W.
;
O'Donnell, M.
Assuntos:
Distortion measurement
;
Energy measurement
;
Humans
;
Image quality
;
Imaging phantoms
;
Phase distortion
;
Probes
;
Speckle
;
Transducers
;
Ultrasonic variables measurement
É parte de:
1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027), 1999, Vol.2, p.1257-1260 vol.2
Descrição:
The coherence factor provides a quantitative measure of image quality. It is defined as the ratio of the coherent sum across array elements to the incoherent sum and measures the distribution of ultrasonic energy between the main beam and side lobes of a radiation pattern. Values range from 0 to 1. For low values most of the energy is outside of the main beam, and for high values it is in the main beam. The authors have applied the van Cittert-Zernike theorem to determine analytic solutions of the coherence factor for single and multi-row arrays. The solution depends only on the number of rows and columns in a transducer array. With a multi-row probe, the authors imaged a uniform tissue-mimicking phantom and saved coherent signals. Images of the phantom were produced based on coherent and incoherent summations of array elements. They then combined the two images to produce a coherence factor image. Within the focal region, average coherence was 0.50 for the phantom which compares favorably to a value of 0.53 from the analytic solution. Next, phase distortions of pi/2 and pi radians were electronically introduced at specific elements, and the phantom was imaged again. Phase distortion greatly effects energy distribution for coherent summations but has a minimal effect on incoherent summations. An introduced distortion of pi/2 decreased the average coherence factor to 0.33. A distortion of pi further decreased it to 0.11. Results of human studies showed decreased average coherence factors compared to undistorted phantom images. These results suggest that the coherence factor provides a quantitative measure of beam quality for in vivo imaging.
Editor:
IEEE
Idioma:
Inglês
This feature requires javascript
This feature requires javascript
Voltar para lista de resultados
This feature requires javascript
This feature requires javascript
Buscando em bases de dados remotas. Favor aguardar.
Buscando por
em
scope:(USP_PRODUCAO),scope:(USP_EBOOKS),scope:("PRIMO"),scope:(USP),scope:(USP_EREVISTAS),scope:(USP_FISICO),primo_central_multiple_fe
Mostrar o que foi encontrado até o momento
This feature requires javascript
This feature requires javascript