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1.
Appl Opt ; 51(3): 365-9, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22270664

RESUMO

We have used molecular beam epitaxy (MBE) based delta-doping technology to demonstrate nearly 100% internal quantum efficiency (QE) on silicon electron-multiplied charge-coupled devices (EMCCDs) for single photon counting detection applications. We used atomic layer deposition (ALD) for antireflection (AR) coatings and achieved atomic-scale control over the interfaces and thin film materials parameters. By combining the precision control of MBE and ALD, we have demonstrated more than 50% external QE in the far and near ultraviolet in megapixel arrays. We have demonstrated that other important device performance parameters such as dark current are unchanged after these processes. In this paper, we briefly review ultraviolet detection, report on these results, and briefly discuss the techniques and processes employed.


Assuntos
Dispositivos Ópticos , Teoria Quântica , Radiometria/instrumentação , Raios Ultravioleta , Elétrons , Desenho de Equipamento , Fótons , Silício/química
2.
Rev Sci Instrum ; 82(4): 043102, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21528990

RESUMO

In this paper we present our system design and methodology for making absolute quantum efficiency (QE) measurements through the vacuum ultraviolet (VUV) and verify the system with delta-doped silicon CCDs. Delta-doped detectors provide an excellent platform to validate measurements through the VUV due to their enhanced UV response. The requirements for measuring QE through the VUV are more strenuous than measurements in the near UV and necessitate, among other things, the use of a vacuum monochromator, good dewar chamber vacuum to prevent on-chip condensation, and more stringent handling requirements.

3.
Appl Opt ; 44(5): 693-700, 2005 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-15751851

RESUMO

Eye tracking is one of the latest technologies that has shown potential in several areas, including biometrics; human-computer interactions for people with and without disabilities; and noninvasive monitoring, detection, and even diagnosis of physiological and neurological problems in individuals. Current noninvasive eye-tracking methods achieve a 30-Hz rate with a low accuracy in gaze estimation, which is insufficient for many applications. We propose a new noninvasive optical eye-tracking system that is capable of operating at speeds as high as 6-12 kHz. A new CCD video camera and hardware architecture are used, and a novel fast algorithm leverages specific features of the input CCD camera to yield a real-time eye-tracking system. A field-programmable gate array is used to control the CCD camera and to execute the operations. Initial results show the excellent performance of our system under severe head-motion and low-contrast conditions.


Assuntos
Algoritmos , Biometria/instrumentação , Diagnóstico por Computador/instrumentação , Movimentos Oculares/fisiologia , Olho/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Oftalmoscópios , Biometria/métodos , Diagnóstico por Computador/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Humanos , Oftalmoscopia/métodos , Fotografação/instrumentação , Fotografação/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravação em Vídeo/instrumentação , Gravação em Vídeo/métodos
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