The interworking between different networks can be effectively realized by implementing all-optical format conversion, and it can improve the flexibility, efficiency and expansibility of the communication system. The all-optical signal processing scheme is only carried out in the optical domain, and it does not require optical-electric-optical (O-E-O) conversion, which greatly improves the transmission rate and processing speed of the communication system. In this paper, an all-optical format conversion scheme from dual-polarization on-off keying (DP-OOK) to quadrature phase shift keying (QPSK) is proposed. The scheme is based on vector phase-sensitive amplification (PSA). Constellation and eye diagram of signals at each stage of system are obtained by simulation, and BER and EVM are calculated to show the performance of the system.
{"title":"DP-OOK to QPSK conversion based on vector phase-sensitive amplification bridging core and access networks","authors":"Zhaoyang Liu, Jiabin Cui, Yuefeng Ji","doi":"10.1117/12.3007642","DOIUrl":"https://doi.org/10.1117/12.3007642","url":null,"abstract":"The interworking between different networks can be effectively realized by implementing all-optical format conversion, and it can improve the flexibility, efficiency and expansibility of the communication system. The all-optical signal processing scheme is only carried out in the optical domain, and it does not require optical-electric-optical (O-E-O) conversion, which greatly improves the transmission rate and processing speed of the communication system. In this paper, an all-optical format conversion scheme from dual-polarization on-off keying (DP-OOK) to quadrature phase shift keying (QPSK) is proposed. The scheme is based on vector phase-sensitive amplification (PSA). Constellation and eye diagram of signals at each stage of system are obtained by simulation, and BER and EVM are calculated to show the performance of the system.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138963455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pengyu Wang, Kun Gao, Xiaodian Zhang, Zibo Hu, Xiansong Gu, Yutong Liu
Hyperspectral images provide significant spatial and spectral information which are widely used in object detection. Two-stage detectors are commonly employed in hyperspectral object detection, where effective region proposals play a crucial role in accurate object localization. However, during non-maximum suppression (NMS) process, the Intersection over Union (IoU) metric based solely on spatial geometric information is inadequate for discriminating between similar proposals. This results in a substantial number of expected proposals with dissimilar characteristics are eliminated. In this paper, we analyze the spectral information in hyperspectral images to distinguish the characteristics of different proposals. Furthermore, this paper proposes the Spectral IoU (SIoU) by introducing spectral signature differences as a new metric. This improves the ability to differentiate between different object instances and increases the recall rate of bounding boxes with high localization confidence in region proposal stage. Moreover, SIoU can be simply integrated into the hyperspectral objection detection frameworks without introducing additional computational complexity. Extensive experiments on the Semi-Supervised Hyperspectral Object Detection Challenge dataset demonstrate the effectiveness of our method.
{"title":"Spectral intersection over union: a bounding box overlap metric for hyperspectral object detection","authors":"Pengyu Wang, Kun Gao, Xiaodian Zhang, Zibo Hu, Xiansong Gu, Yutong Liu","doi":"10.1117/12.3005336","DOIUrl":"https://doi.org/10.1117/12.3005336","url":null,"abstract":"Hyperspectral images provide significant spatial and spectral information which are widely used in object detection. Two-stage detectors are commonly employed in hyperspectral object detection, where effective region proposals play a crucial role in accurate object localization. However, during non-maximum suppression (NMS) process, the Intersection over Union (IoU) metric based solely on spatial geometric information is inadequate for discriminating between similar proposals. This results in a substantial number of expected proposals with dissimilar characteristics are eliminated. In this paper, we analyze the spectral information in hyperspectral images to distinguish the characteristics of different proposals. Furthermore, this paper proposes the Spectral IoU (SIoU) by introducing spectral signature differences as a new metric. This improves the ability to differentiate between different object instances and increases the recall rate of bounding boxes with high localization confidence in region proposal stage. Moreover, SIoU can be simply integrated into the hyperspectral objection detection frameworks without introducing additional computational complexity. Extensive experiments on the Semi-Supervised Hyperspectral Object Detection Challenge dataset demonstrate the effectiveness of our method.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138963571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zonghuan Liu, Anna Zhao, Yunhao Zhang, Chuo Li, Tianhe Wang, Jing Xu
Mugwort floss, valued in traditional Chinese medicine, varies in therapeutic properties and market price based on origin and production year. Traditional identification methods, due to their destructiveness and low accuracy, often confuse mugwort floss with A.stolonifera and cause a testing waste. Hyperspectral Imaging, a non-contact technique, offers potential for rapid identification of such medicinal materials. In this paper, we explore hyperspectral data to differentiate mugwort and A.stolonifera using deep learning and neural networks. Using a massive hyperspectral dataset from mugwort and wormwood from two regions across four years, we analyzed performance using metrics like Accuracy, Specificity, and F1 Score. The self-attention-based Backpropagation Neural Network model showed the most promising results for accurate classification. This approach has potential future applications in various fields using Hyperspectral data
艾绒是传统中药中的珍品，其疗效和市场价格因产地和生产年份而异。传统的鉴别方法由于破坏性大、准确性低，经常会将艾绒与匍匐茎混淆，造成检测浪费。高光谱成像作为一种非接触式技术，为快速鉴定此类药材提供了可能。在本文中，我们利用深度学习和神经网络探索高光谱数据，以区分艾草和匍匐茎。我们使用来自两个地区、历时四年的艾草和匍匐茎的海量高光谱数据集，使用准确性、特异性和 F1 分数等指标分析了性能。基于自我注意的反向传播神经网络模型在准确分类方面显示出最有前途的结果。这种方法未来有可能应用于使用高光谱数据的各个领域。
{"title":"Study on identification method for Artemisia argyi floss","authors":"Zonghuan Liu, Anna Zhao, Yunhao Zhang, Chuo Li, Tianhe Wang, Jing Xu","doi":"10.1117/12.3007562","DOIUrl":"https://doi.org/10.1117/12.3007562","url":null,"abstract":"Mugwort floss, valued in traditional Chinese medicine, varies in therapeutic properties and market price based on origin and production year. Traditional identification methods, due to their destructiveness and low accuracy, often confuse mugwort floss with A.stolonifera and cause a testing waste. Hyperspectral Imaging, a non-contact technique, offers potential for rapid identification of such medicinal materials. In this paper, we explore hyperspectral data to differentiate mugwort and A.stolonifera using deep learning and neural networks. Using a massive hyperspectral dataset from mugwort and wormwood from two regions across four years, we analyzed performance using metrics like Accuracy, Specificity, and F1 Score. The self-attention-based Backpropagation Neural Network model showed the most promising results for accurate classification. This approach has potential future applications in various fields using Hyperspectral data","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138963619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We report a maskless reactive ion etching (RIE) method that employs O2, CHF3 and SF6&O2 gas plasma sequentially to generate nano-cones structures on silicon substrates with good uniformity. In this method, nano-cones are made under carefully-controlled conditions that restrict their width and height to 60 nm and 82 nm, respectively. According to the formation trend of nano-cones under different plasma conditions, the contributing mechanism is discussed. With the multiple effects of etching time, chamber pressure and self-bias voltage, the height, angle and density of nano-cones will be varied within a certain range. Given these variations, a nano-cone structure with good uniformity was generated using the following parameters: etching time of 300 s, chamber pressure of 40 mtorr, self-bias voltage of 75 W, and a SF6&O2 flow ratio of 75 sccm: 75 sccm. The experiment in this report demonstrates a promising way to fabricate silicon-based nano-cone structures for photonic and optoelectronic applications, with advantages of the controllability and compatibility of its dry-etching process.
{"title":"Formation of nano-cone structures on silicon via maskless reactive ion etching","authors":"Jiacheng Lin, Hao Liu, Chen Jiang, Qi Wang, Kai Liu, Xiaomin Ren","doi":"10.1117/12.3008000","DOIUrl":"https://doi.org/10.1117/12.3008000","url":null,"abstract":"We report a maskless reactive ion etching (RIE) method that employs O2, CHF3 and SF6&O2 gas plasma sequentially to generate nano-cones structures on silicon substrates with good uniformity. In this method, nano-cones are made under carefully-controlled conditions that restrict their width and height to 60 nm and 82 nm, respectively. According to the formation trend of nano-cones under different plasma conditions, the contributing mechanism is discussed. With the multiple effects of etching time, chamber pressure and self-bias voltage, the height, angle and density of nano-cones will be varied within a certain range. Given these variations, a nano-cone structure with good uniformity was generated using the following parameters: etching time of 300 s, chamber pressure of 40 mtorr, self-bias voltage of 75 W, and a SF6&O2 flow ratio of 75 sccm: 75 sccm. The experiment in this report demonstrates a promising way to fabricate silicon-based nano-cone structures for photonic and optoelectronic applications, with advantages of the controllability and compatibility of its dry-etching process.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138963678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to avoid an unacceptable in-band S21 flatness in the multi-channel broadband microwave photonic system design, this paper established a relationship between the S21 flatness of a muti-channel broadband link and amplitude and delay errors. According to the deduction, the effect of amplitude error on S21 flatness is much less than that of delay error. And the maximum in-band S21 difference is expressed into a function of the muti-channel delay inconsistency. According to the derivation, for ensuring the in-band S21 flatness of a multi-channel microwave photonic system is less than 3dB, the delay error must be less than 13.89ps. Experimental results and simulation results demonstrate the reliability of the derivation relationship between the in-band S21 flatness and amplitude and delay errors.
{"title":"The effect of amplitude and delay errors on the S21 of a multi-channel broadband microwave photonic link","authors":"Yuan Huang, Shanting Fang, Nan Zhao, Xinmin Zhang","doi":"10.1117/12.3006819","DOIUrl":"https://doi.org/10.1117/12.3006819","url":null,"abstract":"In order to avoid an unacceptable in-band S21 flatness in the multi-channel broadband microwave photonic system design, this paper established a relationship between the S21 flatness of a muti-channel broadband link and amplitude and delay errors. According to the deduction, the effect of amplitude error on S21 flatness is much less than that of delay error. And the maximum in-band S21 difference is expressed into a function of the muti-channel delay inconsistency. According to the derivation, for ensuring the in-band S21 flatness of a multi-channel microwave photonic system is less than 3dB, the delay error must be less than 13.89ps. Experimental results and simulation results demonstrate the reliability of the derivation relationship between the in-band S21 flatness and amplitude and delay errors.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138964468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiaqing Zhao, Xiang Ding, Zhongchao Xu, Zeya Li, Lei Zhang, Yonghong Xue, Shiwei Fan, Rongke Liu
It is of strong practical significance to the management of civil aviation aircrafts through optical detection of aerial targets. A proper detection spectrum can help to enhance the target and suppress the background, guaranteeing the real-time accurate positioning and tracking of aerial targets over a wide range. Firstly, the principle of space-based air target detection is introduced. By analyzing the sources of the target radiation and background radiation, the contrast between target and background radiation intensity is determined as the evaluation standard for space-based detection. In simulations, three typical backgrounds (sea, farm and desert) and Boeing 737 aircraft were taken as examples. The apparent spectral radiance of the background in each spectral band was analyzed with the bulk and apparent spectral radiance of the aerial target under different detection conditions (detection azimuth angle, elevation angle, flight height). By traversing the 2~6 μm spectral range with a maximum spectral width of 1 μm, the contrast between target and background radiation intensity was calculated. 29 alternative spectral bands under 30 working conditions, including different flight altitudes, different backgrounds and different detection azimuth angels, were screened for the contrast between target and background radiation intensity exceeding the threshold of 2000. Considering changes in the upper and lower limit values of the contrast between the target and the background radiation intensity under each spectrum, background, target flight altitude and detection azimuth angle, the 2.53~2.54 μm spectrum could be used as one of the preferred spectral bands of the space-based aerial target optical detection system.
{"title":"Optical spectrum selection for aerial target detection under complex backgrounds","authors":"Jiaqing Zhao, Xiang Ding, Zhongchao Xu, Zeya Li, Lei Zhang, Yonghong Xue, Shiwei Fan, Rongke Liu","doi":"10.1117/12.3002174","DOIUrl":"https://doi.org/10.1117/12.3002174","url":null,"abstract":"It is of strong practical significance to the management of civil aviation aircrafts through optical detection of aerial targets. A proper detection spectrum can help to enhance the target and suppress the background, guaranteeing the real-time accurate positioning and tracking of aerial targets over a wide range. Firstly, the principle of space-based air target detection is introduced. By analyzing the sources of the target radiation and background radiation, the contrast between target and background radiation intensity is determined as the evaluation standard for space-based detection. In simulations, three typical backgrounds (sea, farm and desert) and Boeing 737 aircraft were taken as examples. The apparent spectral radiance of the background in each spectral band was analyzed with the bulk and apparent spectral radiance of the aerial target under different detection conditions (detection azimuth angle, elevation angle, flight height). By traversing the 2~6 μm spectral range with a maximum spectral width of 1 μm, the contrast between target and background radiation intensity was calculated. 29 alternative spectral bands under 30 working conditions, including different flight altitudes, different backgrounds and different detection azimuth angels, were screened for the contrast between target and background radiation intensity exceeding the threshold of 2000. Considering changes in the upper and lower limit values of the contrast between the target and the background radiation intensity under each spectrum, background, target flight altitude and detection azimuth angle, the 2.53~2.54 μm spectrum could be used as one of the preferred spectral bands of the space-based aerial target optical detection system.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Currently, infrared time-sensitive target detection technology is widely used in military and civil applications such as air defense and early warning, maritime surveillance, and precision guidance, but some high-value target images are difficult and expensive to acquire. To address the problems such as the lack of infrared time-sensitive target image data and the lack of multi-scene multi-target data for training, this paper proposes an infrared time-sensitive target data enhancement algorithm based on a generative model, which is a two-stage model. Firstly, in the first stage, the visible images containing time-sensitive targets are converted to infrared images by a modal conversion model based on CUT networks. Then in the second stage a large number of random targets are generated from the converted IR images using an adversarial random sample generation model to achieve the data enhancement effect. The coordinate attention mechanism is also introduced into the generator module in the second stage, which effectively enhances the feature extraction capability of the network. Finally, modal conversion experiments and sample random generation experiments are conducted, and the results show the feasibility of the data enhancement method of generative model proposed in this paper in IR time-sensitive target data enhancement, which provides a strong data support for improving IR time-sensitive target detection algorithm.
{"title":"Infrared time-sensitive target data augmentation algorithm based on generative model","authors":"Siyu Wang, Xiaogang Yang, Ruitao Lu, Qing-ge Li, Jiwei Fan, Zheng-jie Zhu","doi":"10.1117/12.3000067","DOIUrl":"https://doi.org/10.1117/12.3000067","url":null,"abstract":"Currently, infrared time-sensitive target detection technology is widely used in military and civil applications such as air defense and early warning, maritime surveillance, and precision guidance, but some high-value target images are difficult and expensive to acquire. To address the problems such as the lack of infrared time-sensitive target image data and the lack of multi-scene multi-target data for training, this paper proposes an infrared time-sensitive target data enhancement algorithm based on a generative model, which is a two-stage model. Firstly, in the first stage, the visible images containing time-sensitive targets are converted to infrared images by a modal conversion model based on CUT networks. Then in the second stage a large number of random targets are generated from the converted IR images using an adversarial random sample generation model to achieve the data enhancement effect. The coordinate attention mechanism is also introduced into the generator module in the second stage, which effectively enhances the feature extraction capability of the network. Finally, modal conversion experiments and sample random generation experiments are conducted, and the results show the feasibility of the data enhancement method of generative model proposed in this paper in IR time-sensitive target data enhancement, which provides a strong data support for improving IR time-sensitive target detection algorithm.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silu Peng, Chaoyi Zhang, Jiayue Han, Chunyu Li, Hongxi Zhou, Jun Wang
Influenced by the prominent progress of two-dimensional (2D) layered crystals, the fabrication of 2D nanostructures from non-layered materials has attracted more and more attention. Lead selenide (PbSe) is one of the superior candidate materials for photodetector with suitable bandgap and outstanding photoelectric properties. The growth and device preparation of PbSe supply great interest for the development of high-performance infrared photodetectors. Although a lot of efforts have been paid on preparing PbSe nanostructures for miniaturized detectors, it is challenging to synthesize excellent crystallinity and thin 2D PbSe nanosheets because of itsinherent rock salt nonlayered structure. In this work, we employ a catalyst-free facile physical vapor deposition (PVD) method for controllable synthesis of PbSe nanosheets by van der Waals epitaxy technology. By optimizing the growth temperature, PbSe nanosheets from triangular pyramid island to square 2D plane can be obtained. In addition, the 2D PbSe nanosheets detector has a responsivity of 3.03 A/W at the wavelength of 520 nm with the power density of 5.05 mW/cm2. This work provides a facile strategy to synthesize high-quality 2D PbSe nanosheets which have enormous potentials to fabricate high-performance miniaturized photodetector.
{"title":"Catalyst-free physical vapor deposition of crystalline PbSe nanosheets for fabrication of high-performance photodetector","authors":"Silu Peng, Chaoyi Zhang, Jiayue Han, Chunyu Li, Hongxi Zhou, Jun Wang","doi":"10.1117/12.3007081","DOIUrl":"https://doi.org/10.1117/12.3007081","url":null,"abstract":"Influenced by the prominent progress of two-dimensional (2D) layered crystals, the fabrication of 2D nanostructures from non-layered materials has attracted more and more attention. Lead selenide (PbSe) is one of the superior candidate materials for photodetector with suitable bandgap and outstanding photoelectric properties. The growth and device preparation of PbSe supply great interest for the development of high-performance infrared photodetectors. Although a lot of efforts have been paid on preparing PbSe nanostructures for miniaturized detectors, it is challenging to synthesize excellent crystallinity and thin 2D PbSe nanosheets because of itsinherent rock salt nonlayered structure. In this work, we employ a catalyst-free facile physical vapor deposition (PVD) method for controllable synthesis of PbSe nanosheets by van der Waals epitaxy technology. By optimizing the growth temperature, PbSe nanosheets from triangular pyramid island to square 2D plane can be obtained. In addition, the 2D PbSe nanosheets detector has a responsivity of 3.03 A/W at the wavelength of 520 nm with the power density of 5.05 mW/cm2. This work provides a facile strategy to synthesize high-quality 2D PbSe nanosheets which have enormous potentials to fabricate high-performance miniaturized photodetector.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We design a laser driver and temperature control circuit based on the Field Programmable Gate Array (FPGA). Vertical-Cavity Surface-Emitting Laser (VCSEL) is the core device of the nuclear magnetic resonance gyroscope (NMRG). The accuracy of the laser output wavelength greatly affect the detection accuracy of NMRG. In order to improve the accuracy of VCSEL in this application system, in this paper we research the working principle of the laser and analyze the relationship between the laser output wavelength, the driving current and the laser operating temperature through theoretical analysis. We design and built the laser driving and temperature control circuit by using constant current source and the MAX1978, which use FPGA as the main control chip. By setting different voltage values, the laser output corresponds to different wavelengths. We analyze the result of experiment and theoretical calculate through the spectrometer. The result shows that the current regulation error is better than 0.03mA. For the laser temperature control circuit, we used the LTSPICE to simulate the PID control circuit of the compensation loop ,the finally result is consistent with the expected results.
{"title":"Design of driving and temperature control circuitry for VCSEL","authors":"Yan Wang, Zhengguang Wang, Helun Song, Wenbo Han","doi":"10.1117/12.3004979","DOIUrl":"https://doi.org/10.1117/12.3004979","url":null,"abstract":"We design a laser driver and temperature control circuit based on the Field Programmable Gate Array (FPGA). Vertical-Cavity Surface-Emitting Laser (VCSEL) is the core device of the nuclear magnetic resonance gyroscope (NMRG). The accuracy of the laser output wavelength greatly affect the detection accuracy of NMRG. In order to improve the accuracy of VCSEL in this application system, in this paper we research the working principle of the laser and analyze the relationship between the laser output wavelength, the driving current and the laser operating temperature through theoretical analysis. We design and built the laser driving and temperature control circuit by using constant current source and the MAX1978, which use FPGA as the main control chip. By setting different voltage values, the laser output corresponds to different wavelengths. We analyze the result of experiment and theoretical calculate through the spectrometer. The result shows that the current regulation error is better than 0.03mA. For the laser temperature control circuit, we used the LTSPICE to simulate the PID control circuit of the compensation loop ,the finally result is consistent with the expected results.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jian L. Zhan, Yi G. Wu, Sheng Tao, Jing J. Xu, Han Wu, Bin Fan, Hai C. Wang, Bi C. Xia
With the development and progress of society and the acceleration of industry, transportation and urbanization, volatile organic compounds (Volatile Organic Compounds, VOCs) from extensive sources have increasingly prominent effects on the atmospheric environment, and some of them also have irritant, toxic and carcinogenic effects, posing a serious threat to the ecological environment and human health. As the source of energy in the national economy, the petrochemical industry is an important source of man-made VOCs leakage emissions, and has potential huge safety risks. This article reviews the definition of VOCs, source, hazard and traditional leakage detection method, investigate the progress and application of infrared detection technology at home and abroad, infrared detection technology with its non-contact, long distance, high efficiency, wide range, rapid positioning, dynamic intuitive significant advantages, can play an important role in the petrochemical VOCs detection.
{"title":"Overview of the application of VOCs gas leakage infrared thermal imaging technology in the field of petrochemical industry","authors":"Jian L. Zhan, Yi G. Wu, Sheng Tao, Jing J. Xu, Han Wu, Bin Fan, Hai C. Wang, Bi C. Xia","doi":"10.1117/12.3006687","DOIUrl":"https://doi.org/10.1117/12.3006687","url":null,"abstract":"With the development and progress of society and the acceleration of industry, transportation and urbanization, volatile organic compounds (Volatile Organic Compounds, VOCs) from extensive sources have increasingly prominent effects on the atmospheric environment, and some of them also have irritant, toxic and carcinogenic effects, posing a serious threat to the ecological environment and human health. As the source of energy in the national economy, the petrochemical industry is an important source of man-made VOCs leakage emissions, and has potential huge safety risks. This article reviews the definition of VOCs, source, hazard and traditional leakage detection method, investigate the progress and application of infrared detection technology at home and abroad, infrared detection technology with its non-contact, long distance, high efficiency, wide range, rapid positioning, dynamic intuitive significant advantages, can play an important role in the petrochemical VOCs detection.","PeriodicalId":298662,"journal":{"name":"Applied Optics and Photonics China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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