scholarly journals SWIR AOTF Imaging Spectrometer Based on Single-pixel Imaging

Sensors ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 390 ◽  
Author(s):  
Huijie Zhao ◽  
Zefu Xu ◽  
Hongzhi Jiang ◽  
Guorui Jia
Keyword(s):  
Mercury Cadmium Telluride ◽  
Short Wave ◽  
Tunable Filter ◽  
Light Conditions ◽  
Acceptance Angle ◽  
Imaging Spectrometer ◽  
Light Passing ◽  
New Type ◽  
Weak Light ◽  
Single Pixel

An acousto-optic tunable filter (AOTF) is a new type of mono-wavelength generator, and an AOTF imaging spectrometer can obtain spectral images of interest. However, due to the limitation of AOTF aperture and acceptance angle, the light passing through the AOTF imaging spectrometer is weak, especially in the short-wave infrared (SWIR) region. In weak light conditions, the noise of a non-deep cooling mercury cadmium telluride (MCT) detector is high compared to the camera response. Thus, effective spectral images cannot be obtained. In this study, the single-pixel imaging (SPI) technique was applied to the AOTF imaging spectrometer, which can obtain spectral images due to the short-focus lens that collects light into a small area. In our experiment, we proved that the irradiance of a short-focus system is much higher than that of a long-focus system in relation to the AOTF imaging spectrometer. Then, an SPI experimental setup was built to obtain spectral images in which traditional systems cannot obtain. This work provides an efficient way to detect spectral images from 1000 to 2200 nm.

Influence of light on growth, conidiation and the mutual regulation of fumonisin B2 and ochratoxin A biosynthesis by Aspergillus niger

2012 ◽  
Vol 5 (2) ◽  
pp. 169-176 ◽  
Author(s):  
F. Fanelli ◽  
M. Schmidt-Heydt ◽  
M. Haidukowski ◽  
R. Geisen ◽  
A. Logrieco ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Blue Light ◽  
Short Wave ◽  
Light Conditions ◽  
Dark Incubation ◽  
Mutual Regulation ◽  
Blue Wavelength ◽  
Fumonisin B2 ◽  
Dark Production

Aspergillus niger is a fungus able to produce the carcinogenic mycotoxins ochratoxin A (OTA) and fumonisins. We analysed the influence of light of various wavelengths on growth, conidiation, fumonisin B2 (FB2) and OTA biosynthesis by A. niger ITEM 7097. Light from both sides of the spectrum, from long (627 nm) to short wavelengths (470-455 nm), had a stimulating effect on growth, with the highest stimulation under blue (455 nm, 1,700 Lux) and short-wave blue light (390 nm). Conidiation was reduced by 40% under a short blue wavelength (455 nm, 200 Lux), but strongly promoted under light at an even shorter wavelength (390 nm), with an increase of about 200 fold in comparison to the dark. Production of FB2 and OTA was mutually regulated by light. FB2 production was promoted under light conditions: red and blue light in particular increased FB2 biosynthesis by 40%. Conversely, OTA production was greatly inhibited under red and blue light in comparison to dark incubation, with a mean reduction of about 40 fold, indicating a reverse regulation of both biosynthetic pathways. Incubation under a 390 nm wavelength repressed the production of both toxins to non-detectable levels.

Nadir and omnidirectional limb imaging spectrometer based on acousto-optic tunable filter

2019 ◽  
Vol 437 ◽  
pp. 81-89 ◽  
Author(s):  
Xiaoheng Wang ◽  
Xing Zhong ◽  
Ruifei Zhu ◽  
Fang Gao
Keyword(s):  
Tunable Filter ◽  
Imaging Spectrometer

Ultrasensitive broadband photodetectors based on two-dimensional Bi2O2Te films

2021 ◽  
Author(s):  
Pin Tian ◽  
Hongbo Wu ◽  
Libin Tang ◽  
Jinzhong Xiang ◽  
Rongbin Ji ◽  
...  
Keyword(s):  
Large Scale ◽  
2D Materials ◽  
Complementary Metal Oxide Semiconductor ◽  
Cmos Technology ◽  
Photocurrent Density ◽  
Short Wave ◽  
Oxide Semiconductor ◽  
Light Illumination ◽  
Two Dimensional ◽  
Weak Light

Abstract Two-dimensional (2D) materials exhibit many unique optical and electronic properties that are highly desirable for application in optoelectronics. Here, we report the study of photodetector based on 2D Bi2O2Te grown on n-Si substrate. The 2D Bi2O2Te material was transformed from sputtered Bi2Te3 ultrathin film after rapid annealing at 400 ℃ for 10 min in air atmosphere. The photodetector was capable of detecting a broad wavelength from 210 nm to 2.4 μm with excellent responsivity of up to 3x105 and 2x104 AW-1, and detectivity of 4x1015 and 2x1014 Jones at deep ultraviolet (UV) and short-wave infrared (SWIR) under weak light illumination, respectively. The effectiveness of 2D materials in weak light detection was investigated by analysis of the photocurrent density contribution. Importantly, the facile growth process with low annealing temperature would allow direct large-scale integration of the 2D Bi2O2Te materials with complementary metal-oxide–semiconductor (CMOS) technology.

Configurable Passband Imaging Spectrometer Based on Acousto-optic Tunable Filter

2008 ◽  
pp. 206-217 ◽  
Author(s):  
Joan Vila-Francés ◽  
Luis Gómez-Chova ◽  
Julia Amorós-López ◽  
Javier Calpe-Maravilla
Keyword(s):  
Tunable Filter ◽  
Imaging Spectrometer

scholarly journals Polarizer-Free AOTF-Based SWIR Hyperspectral Imaging for Biomedical Applications

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4439
Author(s):  
Vladislav Batshev ◽  
Alexander Machikhin ◽  
Grigoriy Martynov ◽  
Vitold Pozhar ◽  
Sergey Boritko ◽  
...  
Keyword(s):  
Hyperspectral Imaging ◽  
Biomedical Applications ◽  
Cost Effective ◽  
Short Wave ◽  
Tunable Filter ◽  
Quality Analysis ◽  
Imaging Data ◽  
Image Quality Analysis ◽  
Data Volume ◽  
Integrate Design

Optical biomedical imaging in short wave infrared (SWIR) range within 0.9–1.7 μm is a rapidly developing technique. For this reason, there is an increasing interest in cost-effective and robust hardware for hyperspectral imaging data acquisition in this range. Tunable-filter-based solutions are of particular interest as they provide image processing flexibility and effectiveness in terms of collected data volume. Acousto-optical tunable filters (AOTFs) provide a unique set of features necessary for high-quality SWIR hyperspectral imaging. In this paper, we discuss a polarizer-free configuration of an imaging AOTF that provides a compact and easy-to-integrate design of the whole imager. We have carried out image quality analysis of this system, assembled it and validated its efficiency through multiple experiments. The developed system can be helpful in many hyperspectral applications including biomedical analyses.

Developmental Pattern and Structural Organisation of Leaf Chloroplasts in Lepidozamia peroffskyana

1990 ◽  
Vol 38 (1) ◽  
pp. 53 ◽  
Author(s):  
PM Bonatti ◽  
RB Fornasiero
Keyword(s):  
Leaf Development ◽  
Natural Habitat ◽  
High Ratio ◽  
Light Conditions ◽  
Structural Pattern ◽  
Chl A ◽  
Eastern Australia ◽  
Closed Forest ◽  
Weak Light ◽  
Characteristic Features

The ontogenesis of chloroplasts during leaf development in Lepidozamia peroffskyana Regel is described; this cycad lives in the ground layer of the evergreen subtropical closed forest of south-eastern Australia. Characteristic features in young plastids are long bands of multilayered thylakoids, resembling photosynthetic structures of some green algae and ferns. 'Optional' structures, namely prothylakoid bodies and crystalline inclusions, are present in the pre-grana stages, in relation to the slow rate of leaf development. Mature chloroplasts are characterised by a great number of randomly oriented high grana stacks, a lack of starch, a high ratio of appressed to exposed thylakoids, and a low ratio of Chl a to Chl b; these shade features appear coherent with the natural habitat of Lepidozamia. However, since similar structures have been reported in mature chloroplasts of other cycads living in exposed sites, the existence of a genetically superimposed structural pattern is hypothesised, reflecting a primitive adaptation to weak light conditions of this group of ancient seed plants.

Optical design of a short-wave infrared prism-grating imaging spectrometer

2018 ◽  
Vol 57 (34) ◽  
pp. F8
Author(s):  
Jianjun Chen ◽  
Jin Yang ◽  
Jianan Liu ◽  
Jianli Liu ◽  
Ci Sun ◽  
...  
Keyword(s):  
Optical Design ◽  
Short Wave ◽  
Imaging Spectrometer ◽  
Short Wave Infrared
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