This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC- 1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisition mod...This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC- 1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisition module and a wireless alarm module were designed by using the fingerprint sensor FPC1011C and GPRS module SIM100 respectively. The whole system was implemented wireless alarm through messages and GPRS-Internet in the GSM/GPRS web. In order to achieve the simple and high Real-time system, the μC-Linux system migration was also implemented.展开更多
Various novel conjugated polymers(CPs)have been developed for organic photodetectors(OPDs),but their application to practical image sensors such as X-ray,R/G/B,and fingerprint sensors is rare.In this article,we report...Various novel conjugated polymers(CPs)have been developed for organic photodetectors(OPDs),but their application to practical image sensors such as X-ray,R/G/B,and fingerprint sensors is rare.In this article,we report the entire process from the synthesis and molecular engineering of novel CPs to the development of OPDs and fingerprint image sensors.We synthesized six benzo[1,2-d:4,5-d’]bis(oxazole)(BBO)-based CPs by modifying the alkyl side chains of the CPs.Several relationships between the molecular structure and the OPD performance were revealed,and increasing the number of linear octyl side chains on the conjugated backbone was the best way to improve Jph and reduce Jd in the OPDs.The optimized CP demonstrated promising OPD performance with a responsivity(R)of 0.22 A/W,specific detectivity(D^(*))of 1.05×10^(13)Jones at a bias of-1 V,rising/falling response time of 2.9/6.9μs,and cut-off frequency(f_(-3dB))of 134 kHz under collimated 530 nm LED irradiation.Finally,a fingerprint image sensor was fabricated by stacking the POTB1-based OPD layer on the organic thin-film transistors(318 ppi).The image contrast caused by the valleys and ridges in the fingerprints was obtained as a digital signal.展开更多
Chiral enantiomers have different pharmacological and pharmacokinetic characteristics. It is important to strictly detect chiral component for avoiding being harmful to the human body due to side effects. Terahertz (T...Chiral enantiomers have different pharmacological and pharmacokinetic characteristics. It is important to strictly detect chiral component for avoiding being harmful to the human body due to side effects. Terahertz (THz) trace fingerprint detection is essential because the molecular vibrations of various biological substances such as chiral enantiomers are located in THz range. Recent reported enhanced trace fingerprint technologies have some drawbacks. For instance, multiplexing technology suffered from narrow operation range and limitation by frequency resolution of commercial THz time domain spectroscopy;Absorption induced transparency (AIT) identification for narrowband molecular oscillations suffered from random resonance frequency drift due to fabrication error. In this paper, we proposed frequency-selective fingerprint sensor (FSFS), which can experimentally achieve enhanced trace fingerprint detection by both broadband multiplexing technology and robust AIT identification. Such FSFS is based on polarization independent reconfiguration metasurfaces array. Broadband absorption lines of trace-amount chiral carnitine were boosted with absorption enhancement factors of about 7.3 times based on frequency-selective multiplexing at 0.95-2.0 THz. Enhanced trace narrowband α-lactose fingerprint sensing can be observed at several array structures with absorption enhancement factors of about 7 times based on AIT, exhibiting good robustness. The flexibility and versatility of proposed FSFS has potential applications for boosting trace chiral enantiomer detection as well as diversity of molecular fingerprints identification by both multiplexing and AIT.展开更多
This paper presents a 591×438-DPI ultrasonic fingerprint sensor.The sensor is based on a piezoelectric micromachined ultrasonic transducer(PMUT)array that is bonded at wafer-level to complementary metal oxide sem...This paper presents a 591×438-DPI ultrasonic fingerprint sensor.The sensor is based on a piezoelectric micromachined ultrasonic transducer(PMUT)array that is bonded at wafer-level to complementary metal oxide semiconductor(CMOS)signal processing electronics to produce a pulse-echo ultrasonic imager on a chip.To meet the 500-DPI standard for consumer fingerprint sensors,the PMUT pitch was reduced by approximately a factor of two relative to an earlier design.We conducted a systematic design study of the individual PMUT and array to achieve this scaling while maintaining a high fill-factor.The resulting 110×56-PMUT array,composed of 30×43-μm^(2) rectangular PMUTs,achieved a 51.7% fill-factor,three times greater than that of the previous design.Together with the custom CMOS ASIC,the sensor achieves 2 mV kPa^(−1) sensitivity,15 kPa pressure output,75μm lateral resolution,and 150μm axial resolution in a 4.6 mm×3.2 mm image.To the best of our knowledge,we have demonstrated the first MEMS ultrasonic fingerprint sensor capable of imaging epidermis and sub-surface layer fingerprints.展开更多
Fingerprint is a very popular and an ancient biometric technology to uniquely identify a person. In this paper, a fingerprint matcher is proposed which uses the global and local adaptive binarization and global minuti...Fingerprint is a very popular and an ancient biometric technology to uniquely identify a person. In this paper, a fingerprint matcher is proposed which uses the global and local adaptive binarization and global minutia features. The fingerprint data is collected using three different authentication devices based on optical sensors. The experimental results are compared with the National Institute of Standards and Technology （NIST） Bozorth algorithm and various authentication fingerprint sensors. The accuracy of the proposed algorithm has been improved significantly compared with that of the NIST Bozorth algorithm.展开更多
WiFi fingerprinting is the method of recording WiFi signal strength from access points （AP） along with the positions at which they were recorded, and later matching those to new mea- surements for indoor positioning...WiFi fingerprinting is the method of recording WiFi signal strength from access points （AP） along with the positions at which they were recorded, and later matching those to new mea- surements for indoor positioning. Inertial positioning utilizes the accelerometer and gyroscopes for pedestrian positioning. However, both methods have their limitations, such as the WiFi fluctuations and the accumulative error of inertial sensors. Usually, the filtering method is used for integrating the two approaches to achieve better location accuracy. In the real environments, especially in the indoor field, the APs could be sparse and short range. To overcome the limitations, a novel particle filter approach based on Rao Blackwellized particle filter （RBPF） is presented in this paper. The indoor environment is divided into several local maps, which are assumed to be independent of each other. The local areas are estimated by the local particle filter, whereas the global areas are com- bined by the global particle filter. The algorithm has been investigated by real field trials using a WiFi tablet on hand with an inertial sensor on foot. It could be concluded that the proposed method reduces the complexity of the positioning algorithm obviously, as well as offers a significant improvement in position accuracy compared to other conventional algorithms, allowing indoor positioning error below 1.2 m.展开更多
文摘This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC- 1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisition module and a wireless alarm module were designed by using the fingerprint sensor FPC1011C and GPRS module SIM100 respectively. The whole system was implemented wireless alarm through messages and GPRS-Internet in the GSM/GPRS web. In order to achieve the simple and high Real-time system, the μC-Linux system migration was also implemented.
基金funded by the National Research Foundation(NRF)of Korea(2020M3H4A3081816,RS-2023-00304936,and RS-2024-00398065).
文摘Various novel conjugated polymers(CPs)have been developed for organic photodetectors(OPDs),but their application to practical image sensors such as X-ray,R/G/B,and fingerprint sensors is rare.In this article,we report the entire process from the synthesis and molecular engineering of novel CPs to the development of OPDs and fingerprint image sensors.We synthesized six benzo[1,2-d:4,5-d’]bis(oxazole)(BBO)-based CPs by modifying the alkyl side chains of the CPs.Several relationships between the molecular structure and the OPD performance were revealed,and increasing the number of linear octyl side chains on the conjugated backbone was the best way to improve Jph and reduce Jd in the OPDs.The optimized CP demonstrated promising OPD performance with a responsivity(R)of 0.22 A/W,specific detectivity(D^(*))of 1.05×10^(13)Jones at a bias of-1 V,rising/falling response time of 2.9/6.9μs,and cut-off frequency(f_(-3dB))of 134 kHz under collimated 530 nm LED irradiation.Finally,a fingerprint image sensor was fabricated by stacking the POTB1-based OPD layer on the organic thin-film transistors(318 ppi).The image contrast caused by the valleys and ridges in the fingerprints was obtained as a digital signal.
基金Basic Science Center Project of the National Natural Science Foundation of China[Grant No.61988102]National Natural Science Foundation of China[Grant No.62275157]+1 种基金Shanghai Shuguang Program[Grant No.18SG44]111 Project[Grant No.D18014].
文摘Chiral enantiomers have different pharmacological and pharmacokinetic characteristics. It is important to strictly detect chiral component for avoiding being harmful to the human body due to side effects. Terahertz (THz) trace fingerprint detection is essential because the molecular vibrations of various biological substances such as chiral enantiomers are located in THz range. Recent reported enhanced trace fingerprint technologies have some drawbacks. For instance, multiplexing technology suffered from narrow operation range and limitation by frequency resolution of commercial THz time domain spectroscopy;Absorption induced transparency (AIT) identification for narrowband molecular oscillations suffered from random resonance frequency drift due to fabrication error. In this paper, we proposed frequency-selective fingerprint sensor (FSFS), which can experimentally achieve enhanced trace fingerprint detection by both broadband multiplexing technology and robust AIT identification. Such FSFS is based on polarization independent reconfiguration metasurfaces array. Broadband absorption lines of trace-amount chiral carnitine were boosted with absorption enhancement factors of about 7.3 times based on frequency-selective multiplexing at 0.95-2.0 THz. Enhanced trace narrowband α-lactose fingerprint sensing can be observed at several array structures with absorption enhancement factors of about 7 times based on AIT, exhibiting good robustness. The flexibility and versatility of proposed FSFS has potential applications for boosting trace chiral enantiomer detection as well as diversity of molecular fingerprints identification by both multiplexing and AIT.
文摘This paper presents a 591×438-DPI ultrasonic fingerprint sensor.The sensor is based on a piezoelectric micromachined ultrasonic transducer(PMUT)array that is bonded at wafer-level to complementary metal oxide semiconductor(CMOS)signal processing electronics to produce a pulse-echo ultrasonic imager on a chip.To meet the 500-DPI standard for consumer fingerprint sensors,the PMUT pitch was reduced by approximately a factor of two relative to an earlier design.We conducted a systematic design study of the individual PMUT and array to achieve this scaling while maintaining a high fill-factor.The resulting 110×56-PMUT array,composed of 30×43-μm^(2) rectangular PMUTs,achieved a 51.7% fill-factor,three times greater than that of the previous design.Together with the custom CMOS ASIC,the sensor achieves 2 mV kPa^(−1) sensitivity,15 kPa pressure output,75μm lateral resolution,and 150μm axial resolution in a 4.6 mm×3.2 mm image.To the best of our knowledge,we have demonstrated the first MEMS ultrasonic fingerprint sensor capable of imaging epidermis and sub-surface layer fingerprints.
文摘Fingerprint is a very popular and an ancient biometric technology to uniquely identify a person. In this paper, a fingerprint matcher is proposed which uses the global and local adaptive binarization and global minutia features. The fingerprint data is collected using three different authentication devices based on optical sensors. The experimental results are compared with the National Institute of Standards and Technology （NIST） Bozorth algorithm and various authentication fingerprint sensors. The accuracy of the proposed algorithm has been improved significantly compared with that of the NIST Bozorth algorithm.
文摘WiFi fingerprinting is the method of recording WiFi signal strength from access points （AP） along with the positions at which they were recorded, and later matching those to new mea- surements for indoor positioning. Inertial positioning utilizes the accelerometer and gyroscopes for pedestrian positioning. However, both methods have their limitations, such as the WiFi fluctuations and the accumulative error of inertial sensors. Usually, the filtering method is used for integrating the two approaches to achieve better location accuracy. In the real environments, especially in the indoor field, the APs could be sparse and short range. To overcome the limitations, a novel particle filter approach based on Rao Blackwellized particle filter （RBPF） is presented in this paper. The indoor environment is divided into several local maps, which are assumed to be independent of each other. The local areas are estimated by the local particle filter, whereas the global areas are com- bined by the global particle filter. The algorithm has been investigated by real field trials using a WiFi tablet on hand with an inertial sensor on foot. It could be concluded that the proposed method reduces the complexity of the positioning algorithm obviously, as well as offers a significant improvement in position accuracy compared to other conventional algorithms, allowing indoor positioning error below 1.2 m.
