Development and Investigation of a Long-Range Time-of-Flight and Color Imaging System

AbstractUnderstanding stray light (SL) is a crucial aspect in the development of high-end optical instruments, for instance space telescopes. As it drives image quality, SL must be controlled by design and characterized experimentally. However, conventional SL characterization methods are limited as they do not provide information on its origins. The problem is complex due to the diversity of light interaction processes with surfaces, creating various SL contributors. Therefore, when SL level is higher than expected, it can be difficult to determine how to improve the system. We demonstrate a new approach, ultrafast time-of-flight SL characterization, where a pulsed laser source and a streak camera are used to record individually SL contributors which travel with a specific optical path length. Furthermore, the optical path length offers a means of identification to determine its origin. We demonstrate this method in an imaging system, measuring and identifying individual ghosts and scattering components. We then show how it can be used to reverse-engineer the instrument SL origins.

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A Dual-Color Imaging System for Sugarcane Smut Fungus Sporisorium scitamineum

Plant Disease ◽

10.1094/pdis-02-16-0257-sr ◽

2016 ◽

Vol 100 (12) ◽

pp. 2357-2362 ◽

Cited By ~ 6

Author(s):

Meixin Yan ◽

Enping Cai ◽

Jianuan Zhou ◽

Changqing Chang ◽

Pinggen Xi ◽

...

Keyword(s):

Life Cycle ◽

Fluorescent Protein ◽

Imaging System ◽

Abiotic Factors ◽

Smut Fungus ◽

Color Imaging ◽

Sporisorium Scitamineum ◽

Dual Color ◽

Life Cycle Development ◽

Whole Life Cycle

The life cycle of the sugarcane smut fungus Sporisorium scitamineum is a multistep process. Haploid sporidia of compatible (MAT-1 versus MAT-2) mating types fuse to generate pathogenic dikaryotic hyphae to infect the host. Within the host tissues, diploid teliospores are formed and induce a characteristic sorus that looks like a black whip. The diploid teliospores germinate to form haploid sporidia by meiosis. In order to monitor fungal development throughout the whole life cycle, we expressed the green fluorescent protein (GFP) and red fluorescent protein (RFP) in S. scitamineum MAT-1 and MAT-2 sporidia, respectively. Observation by epifluorescence microscope showed that conjugation tube formation and sporidia fusion occurred at 4 to 8 h, and formation of dikaryotic filaments was detected at 12 h after mating. The resultant teliospores, with diffused GFP and RFP, underwent meiosis as demonstrated by septated hypha with single fluorescent signal. We demonstrated that GFP- and RFP-tagged strains can be used to study the life cycle development of the fungal pathogen S. scitamineum, including the sexual mating and meiosis events. This dual-color imaging system would be a valuable tool for investigation of biotic and abiotic factors that might affect the fungal life cycle development and pathogenesis.

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Color Document Imaging with Amorphous Silicon Sensor Arrays

MRS Proceedings ◽

10.1557/proc-336-873 ◽

1994 ◽

Vol 336 ◽

Cited By ~ 9

Author(s):

R. A. Street ◽

X. D. Wu ◽

R. Weisfield ◽

S. Nelson ◽

P. Nylen

Keyword(s):

Amorphous Silicon ◽

High Speed ◽

Imaging System ◽

Sensor Arrays ◽

Color Imaging ◽

Silicon Sensors ◽

Imaging Properties ◽

Color Filters ◽

Illumination Source ◽

Silicon Sensor

ABSTRACTWe describe the performance of an amorphous silicon imaging system designed for high speed (>10 frames/sec) scanning of a document. The system comprises a new page-sized sensor array with 1536×1920 pixels, an illumination source, and the readout electronics. With appropriate color filters, one can achieve color imaging of a document without the registration problems associated with linear scanners. We describe the color imaging properties and discuss how the color response, sensitivity and uniformity depend on the properties of the amorphous silicon sensors.

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Time of flight dual photon emission computed tomography

Scientific Reports ◽

10.1038/s41598-020-76526-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Chih-Chieh Chiang ◽

Chun-Chao Chuang ◽

Yu-Ching Ni ◽

Meei-Ling Jan ◽

Keh-Shih Chuang ◽

...

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Imaging System ◽

Detection System ◽

Photon Emission ◽

Time Of Flight ◽

Emission Computed Tomography ◽

List Mode ◽

Emission Computed ◽

Photon Emission Computed Tomography

Abstract Time-of-flight dual photon emission computed tomography (TOF-DuPECT) is an imaging system that can obtain radionuclide distributions using time information recorded from two cascade-decay photons. The potential decay locations in the image space, a hyperbolic response curve, can be determined via time-difference-of-arrival (TDOA) estimations from two instantaneous coincidence photons. In this feasibility study, Monte Carlo simulations were performed to generate list-mode coincidence data. A full-ring positron emission tomography-like detection system geometry was built in the simulation environment. A contrast phantom and a Jaszczak-like phantom filled with Selenium-75 (Se-75) were used to evaluate the image quality. A TOF-DuPECT system with varying coincidence time resolution (CTR) was then evaluated. We used the stochastic origin ensemble (SOE) algorithm to reconstruct images from the recorded list-mode data. The results indicate that the SOE method can be successfully employed for the TOF-DuPECT system and can achieve acceptable image quality when the CTR is less than 100 ps. Therefore, the TOF-DuPECT imaging system is feasible. With the improvement of the detector with time, future implementations and applications of TOF-DuPECT are promising. Further quantitative imaging techniques such as attenuation and scatter corrections for the TOF-DuPECT system will be developed in future.

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Research on long-range laser active imaging system applied in adverse weather conditions

10.1117/12.2034683 ◽

2013 ◽

Author(s):

Zhi-gang Gai ◽

Meng-de Liu ◽

Li Yang ◽

V. V. Kabanov ◽

Lei Shi ◽

...

Keyword(s):

Long Range ◽

Imaging System ◽

Weather Conditions ◽

Adverse Weather Conditions ◽

Adverse Weather ◽

Active Imaging

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A systems approach to custom VLSI for a digital color imaging system

IEEE Journal of Solid-State Circuits ◽

10.1109/4.78243 ◽

1991 ◽

Vol 26 (5) ◽

pp. 727-737 ◽

Cited By ~ 5

Author(s):

L.J. D'Luna ◽

K.A. Parulski

Keyword(s):

Systems Approach ◽

Imaging System ◽

Color Imaging ◽

Digital Color Imaging

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Determination of Drift, Extended State Mobility and Recombination Lifetime in Compensated a-Si:H by Photomixing

MRS Proceedings ◽

10.1557/proc-297-407 ◽

1993 ◽

Vol 297 ◽

Cited By ~ 4

Author(s):

Yi Tang ◽

R. Braunstein ◽

Bolko Von Roedern ◽

F.R. Shapiro

Keyword(s):

Long Range ◽

Time Of Flight ◽

Transport Processes ◽

Extended State ◽

Recombination Lifetime ◽

Potential Fluctuations ◽

Range Potential

Mobilities of a series of compensated a-Si:H samples, measured earlier by the time-of-flight technique [1], were determined by the technique of photomixing. We have found that both the extended state and the drift mobilities decrease as the compensation increases. Modelling these transport processes in the context of the photomixing technique, it is shown that long-range potential fluctuations can account for the decrease in the extended state mobility in compensated samples.

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