Browsing by Author "Wang, Yao-Chin"

Now showing 1 - 18 of 18

A wireless and wearable measurement system for human body electrostatic monitoring application
(2018-03-01)
Wang, Yao-Chin
;
Lin, Nan-Chun
;
Lin, Bor-Shyh
;
影像與生醫光電研究所
;
Institute of Imaging and Biomedical Photonics
In particular, electrostatic discharge (ESD) and electric overstress (EOS), for the production assembly, were concluded as the common problems for all electronic manufacturers in worldwide. Uncontrollable and invisible electrostatic discharge events were the major problems, because production quality was performed by well-controlled electrostatic discharge and electric overstress. Currently, it was passively managed the electrostatic grounding path by a connection on the assembly line, the correct wearing of electrostatic ground wrist/ankle straps, and the installation of static ionizers on top of the riskiest workstations to dissipate the electrostatic energy, with the regular check of electrostatic discharge being eliminated or dissipated by static ionizers. The above methods could merely detect fixed locations, but could not real time detect the electrostatic conditions of an operator and record the related events for the database analysis. In order to improve the above issue, the study proposed a wearable and wireless human body electrostatic monitoring system to real-time detect the ESD event of an operator and record the ESD events for the database analysis. By using the real-time alert mechanism, the proposed system could effectively prevent these ESD damages: (1) could inform the operator to immediately discharge the cumulative electric charge; (2) could be transmit to the back-end host system via Bluetooth to make up the careless mistake in the operation, and this alert could be regarded as the second prevention; (3) could be recorded in database for successive data analyses. Finally, the proposed system was also validated and applied in the production assembly and the experimental results indicated that it could exactly provide an effective way to reduce the influence of ESD/EOS.
An Optomechatronics Inspection Technique of TFT Array Flaw Applied to Medical Display
(2015-02-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
光電系統研究所
;
影像與生醫光電研究所
;
生醫電子轉譯研究中心
For medical display, the pixels on array panels are getting smaller. Therefore, flaw detection and measurement are getting more difficult and critical for managing yield and quality in a thin-film-transistor (TFT) array process. The TFT array testing technique has been used for flaw detection and process yield control. As the TFT array pixel size is getting smaller and the resolution is getting higher, both of them have encountered a performance limitation in detecting the critical small-pixel defect for the ultrahigh-resolution TFT array such as medical display applications. In this study, a novel approach for flaw detection is proposed. The proposed optomechatronics technique with interdigitized shorting bar design configuration is used for inspection. The experimental results show that, by using the voltage imaging technique, the flaw detection rate for small-pixel size, high-resolution TFT array has been effectively improved from 50% to 80%. The detected subpixel size for a TFT array panel can be smaller than 53 mu m for a 30-inch ultrahigh-definition medical display application.
Auto Defect Detection of A-IGZO Thin Film Transistor Backplane on Foldable Medical Array Panel Application
(2017-01-01)
Hung, Yu-Min
;
Wang, Yao-Chin
;
Yang, Yu-Ching
;
Lin, Bor-Shyh
;
Lin, Bor-Shing
This article reported on the pixel flaw detection properties of amorphous In-Ga-Zn-O-based active thin film transistors on flexible medical panel substrate application, which is using the non-invasive optoelectronic transforming inspection technique. The experimental data exactly showed good flaw detection rate > 90% and stable uniformity < 5%. Currently, it is a popular method with electrical testing and detection with advantages of ultrahigh resolution and small-pixel-sized medical panel, and no contact damaged to the application of flexible medical panel substrates.
Critical point defect detection for small-pixel thin-film transistor array applied to medical display
(2013-09-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
光電系統研究所
;
影像與生醫光電研究所
;
生醫電子轉譯研究中心
Design of Wearable Headset with Steady State Visually Evoked Potential-Based Brain Computer Interface
(2019-10-01)
Lin, Bor-Shyh
;
Lin, Bor-Shing
;
Yen, Tzu-Hsiang
;
Hsu, Chien-Chin
;
Wang, Yao-Chin
Brain-computer interface (BCI) is a system that allows people to communicate directly with external machines via recognizing brain activities without manual operation. However, for most current BCI systems, conventional electroencephalography (EEG) machines and computers are usually required to acquire EEG signal and translate them into control commands, respectively. The sizes of the above machines are usually large, and this increases the limitation for daily applications. Moreover, conventional EEG electrodes also require conductive gels to improve the EEG signal quality. This causes discomfort and inconvenience of use, while the conductive gels may also encounter the problem of drying out during prolonged measurements. In order to improve the above issues, a wearable headset with steady-state visually evoked potential (SSVEP)-based BCI is proposed in this study. Active dry electrodes were designed and implemented to acquire a good EEG signal quality without conductive gels from the hairy site. The SSVEP BCI algorithm was also implemented into the designed field-programmable gate array (FPGA)-based BCI module to translate SSVEP signals into control commands in real time. Moreover, a commercial tablet was used as the visual stimulus device to provide graphic control icons. The whole system was designed as a wearable device to improve convenience of use in daily life, and it could acquire and translate EEG signal directly in the front-end headset. Finally, the performance of the proposed system was validated, and the results showed that it had excellent performance (information transfer rate = 36.08 bits/min).
Develop a Low-Temperature In-Line Sputtering System for Flexible and Thinned-Glass Substrates
(2016-11)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
Yang, Zu-Po
;
光電學院
;
光電系統研究所
Flexible and thinned glass substrates are two kinds of important substrates but are difficult to handle by conventional in-line sputtering system for mass production. Here, we designed and developed an in-line sputtering system for mass production that can handle these two kinds of substrates. The key of this success is the well heat management of this system. With the method of multiple cycles of deposition and cooling, this system demonstrated the deposition of thick copper film on flexible substrates at substrate temperature less than 120 degrees C. The thickness and cooling rate for one cycle are similar to 800 nm and 0.5 degrees C/s, respectively. Additionally, the processes of deposition and cooling are parallel in our system. By redesigning the mechanical structure of substrate carrier, the effect of the thermal stress change of substrate carrier on thinned glass substrates is minimized; therefore, our system can uniformly deposited ITO film on large-size thinned glass substrates. The values of sheet resistance, transmittance, and their uniformity are acceptable for industry. Moreover, all the processes of this system are automatic which is ready for mass production.
Dual wavelength silicon-based-photodetector for biomedical sensing system applications
(2016)
Wang, Yao-Chin
;
Yang, Zu-Po
;
Lin, Bor-Shyh
;
光電系統研究所
;
影像與生醫光電研究所
the article proposed dual wavelength silicon based photo detector with multi-layer structure, was fabricated and characterized with dual wavelength enhanced operating. We proposed the dual wavelength response of the silicon based bio-photo-detector. It can be enhanced by introducing thin porous silicon layer as the base region of transistor. The device process of manufacture is suitable in design of visible-light sensitive bio-photo-detectors. The experimental results showed that the dual wavelength responses in the developed devices were enhanced as compared to the silicon-based homo-junction photo-detectors in optical parameters, which indicated that the developed bio-photo-detector showed potential for practical silicon based biomedical device and system applications.
Dynamically tuning the correlated color temperature of white light-emitting electrochemical cells with electrochromic filters
(2017-09-01)
Chiou, Bo-Ruei
;
Lee, Hsiao-Chin
;
Jang, Yea-Fen
;
Yang, Zu-Po
;
Wang, Yao-Chin
Recently, white solid-state light-emitting electrochemical cells (LECs) have drawn great attention since they exhibit advantages such as low-voltage operation, compatibility with solution processes and employing inert cathode metals. Since different correlated color temperatures (CCTs) of background illumination are necessary for various lighting applications, a real-time tunable CCT of white LECs would be highly desired in modern smart lighting systems. In this work, a widely and dynamically tuning CCT (>10000 K) of white LEC is demonstrated by employing an electrochromic device (ECD) as a real-time controllable color filter. By increasing the applied bias on the ECD to attenuate more the red parts of white EL from the white LEC, the LEC-based white light source becomes more bluish and, in consequence, shows higher CCT. This proposed LEC-based white light source with the characteristics of wide CCT range and real-time tunability is suitable for most lighting applications and modern smart lighting systems. (C) 2017 Elsevier B.V. All rights reserved.
Electro-optical measurement and process inspection for integrated gate driver circuit on thin-film-transistor array panels
(2015-06-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
Chan, Ming-Che
;
光電系統研究所
;
影像與生醫光電研究所
The study proposed electro-optical measurement and process inspection for integrated-gate-driver circuit on thin-film-transistor array panel. It is a trend on the developing with application of integrated gate driver circuit in the narrow frame design and reduction of driver integrated circuit chips in thin-film-transistor array backplane. Over the past, it cannot detect that contain integrated-gate-driver circuit on thin-film-transistor array panel, especially in process defects of the integrated-gate-driver circuit. The paper proposed a process inspection for the defects in integrated-gate-driver circuit on the thin-film-transistor array panel by the voltage imaging technique and reported good performance. (C) 2015 Elsevier Ltd. All rights reserved.
Estimation on the effect of local brain cooling after head injury by wireless near infrared spectroscopy
(2017-02)
Wang, Che-Chuan
;
Wang, Yao-Chin
;
Liao, Yi-Chien
;
Wang, Jhi-Joung
;
Chan, Ming-Che
Local brain cooling is a way to treat traumatic brain injury and prevent secondary brain injury. The aim of this study is to explore the change of hemoglobin during local brain cooling after traumatic brain injury, and assess the treatment effect by using the wireless near infrared spectroscopy (NIRS) system. Assign all male Sprague Dawley rats to three groups randomly: sham, fluid percussion injury (FPI), FPI + cooling. After executing fluid percussion injury, a cold water bag (5-6 degrees C) was used locally for 30 min. The wireless NIRS system which we developed was used to monitor the concentration change of HbO(2), HbR and HbT. And other physiological parameters, ICP and CPP, were also monitored during the experiment. According to previous results, local brain cooling could reduce infarction volume while traumatic brain injury occurs. Similarly, our results show that local brain cooling caused oxy-hemoglobin, the tissue oxygen saturation and CPP increase and ICP decreased. From the results, the hemoglobin parameters, ICP and MAP were affected by temperature. And local cooling after FPI might have clinical benefits in the future. In addition, the wireless NIRS system might be an instrument to assess the effect of hypothermia. (C) 2016 Elsevier Ltd. All rights reserved.
Flaw detection and measurement for 4K Ultra HD thin-film-transistor array panel
(2014-05-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
Yang, Kei-Hsiung
;
光電系統研究所
;
影像與生醫光電研究所
Display pixels of liquid-crystal-display televisions (LCD TVs) on thin-film-transistor (TFT) array are getting smaller. This paper introduced the method of voltage imaging technique, which developed and provides initial insight into the thin-film-transistor array flaw detection and measurement for ultra-high-definition (Ultra HD, UHD) LCD TV application. We proposed the measurement of flaw detection, based on TFT array testing and characterization with respect to opto-electric transformation measurement. (C) 2014 Elsevier Ltd. All rights reserved.
Flaw detection and measurement for mobile display
(2014-11-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
光電系統研究所
;
影像與生醫光電研究所
;
生醫電子轉譯研究中心
With advanced small-pixel and high-resolution mobile displays, the display are obtaining smaller pixel size and higher resolution on thin-film-transistor (TFT) array process. This study proposed the flaw detection and measurement in small pixel design mobile displays based on oxide-semiconductor-based TFT liquid crystal displays. The measurement is with respect to electrical-physic characterisation metrics and observer studies. Studies resulted in small-sized pixel TFT array between the flaw detection performance and maker preference approaches. Detection performance factors provided information on the differences among small pixel design for advanced mobile display technologies. The results of the detection performance and preference study showed that the application for advanced mobile display panels. It also shown that critical pixel defect played an important role than previously seen in non-small pixel TFT array panels for managing process yield. The method of voltage imaging for detection, developed in this study provides an initial insight into the high resolution of small-sized pixel designs for advanced mobile displays with precision and diagnostic images in portable devices.
Initial Phase of Building up a Portable Multiple-Wavelength Biomedical Sensing System
(2018-01-01)
Yeh, Yen-Lin
;
Yang, Zu-Po
;
Wang, Yao-Chin
;
光電系統研究所
;
Institute of Photonic System
Biomedical materials have different optical properties (e.g. absorption) for different wavelengths. Therefore, probing biomedical materials with multiple wavelengths not only can get in-depth understanding of the detected biomedical materials but also can differentiate the detected biomedical materials. To achieve this purpose, in this conference paper, we present our initial results of building up a portable multiple-wavelength biomedical sensing system. At this initial phase, we assembled this kind of system with multiple wavelengths of light sources and photodetectors and preliminarily tested the absorbance of the glucose solutions with different concentrations. The result shows good linearity of the absorbance of the glucose solution with concentration. In addition, we also measured the absorbance of the glucose solutions using a broadband white light source and a spectrometer. This result also exhibits linearity but different slop of absorbance with glucose concentration, which confirms the linearity result obtained from the built sensing system. The difference of slop maybe relates to the difference of optical design between these two systems.
Non-invasive biopsy of doped-ions inside optical substrate by modified two-photon microscopy
(2015-01-26)
Wang, Yao-Chin
;
Chen, Hsiang-Ning
;
Li, Wang-Yang
;
Chan, Ming-Che
;
光電系統研究所
Doped-ion based optical elements play key roles in optical signal processes, including amplification, absorption, wavelength-filtering, lighting, and polarizing plate. Non-invasively mapping the spatial distribution of the ion concentrations in these optical elements is highly desirable either during the fabrication process or to determine their optical qualities. In this work, we applied modified two-photon fluorescence (mTPF) microscopy to trace the ion-distributions deep inside the optical elements. For demonstration purposes, polyvinyl alcohol (PVA) polymer films inside polarizing plates are taken as an example, where the spatial distributions of Iodine-dyed ions were measured by the m-TPF microscope in a fast and non-invasive way. The durability of the polarizer films can be distinguished from the axial distribution of the Iodine-dyed ions, without the need to perform a biopsy. This proposed method and demonstrated results show great potential for monitoring the spatial distributions of doped-ions in the optical elements quickly and non-destructively, which would be of great benefit in both scientific research and industrial applications. (C) 2015 Optical Society of America
Short wavelength enhanced phototransistor with n-doped porous silicon layer
(2016-05-26)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
Yang, Zu-Po
;
光電學院
;
College of Photonics
A phototransistor with aluminium (Al)/porous silicon (Si)/epitaxial-Si structures was proposed and was fabricated and characterised with short wavelength enhanced operating. We proposed the short wavelength response of the Si-based thin film phototransistor; it can be enhanced by introducing thin porous Si (PS) layer as the base region of transistor. The porous process of device manufacture is suitable for applications in design of visible-light sensitive phototransistors. Experimental results showed that the short wavelength responses in the developed devices were enhanced as compared with the Si-based homojunction transistors, this comparably medium optical gain indicated that the developed Al/PSi/epitaxial-Si heterojunction thin film phototransistor got potential for practical Si-based optical-electron integrated-circuit and biophotonics applications.
Small-pixel TFT flaw detection and measurement using voltage imaging technique
(2014-04-01)
Wang, Yao-Chin
;
Lin, Bor-Shyh
;
光電系統研究所
;
影像與生醫光電研究所
;
生醫電子轉譯研究中心
The paper proposed the characteristics of flaw measurement in small-pixel design mobile displays based on TFT array panel with respect to electrical-optic characterization. For advanced small-pixel and high-resolution mobile display applications, the display pixels on array process are smaller, detecting small-pixel defect played an important role than previously seen in non-small-pixel TFT array panels for managing process yield. The study resulted in small-pixel size TFT array show the flaw detection performance and preference approaches using the voltage imaging technique. It provides an initial insight into the high-resolution of small-pixel size designs for advanced mobile displays application. (C) 2013 Elsevier Ltd. All rights reserved.
Substrate-insensitive atomic layer deposition of plasmonic titanium nitride films
(2017-03-01)
Yu, Ing-Song
;
Cheng, Hsyi-En
;
Chang, Chun-Chieh
;
Lin, Yan-Wei
;
Chen, Hou-Tong
The plasmonic properties of titanium nitride (TiN) films depend on the type of substrate when using typical deposition methods such as sputtering. Here we show atomic layer deposition (ALD) of TiN films with very weak dependence of plasmonic properties on the substrate, which also suggests the prediction and evaluation of plasmonic performance of TiN nanostructures on arbitrary substrates under a given deposition condition. Our results also observe that substrates with more nitrogen-terminated (N-terminated) surfaces will have significant impact on the deposition rate as well as the film plasmonic properties. We further illustrate that the plasmonic properties of ALD TiN films can be tailored by simply adjusting the deposition and/or post-deposition annealing temperatures. Such characteristics and the capability of conformal coating make ALD TiN films on templates ideal for applications that require the fabrication of complex 3D plasmonic nanostructures. (C) 2017 Optical Society of America
The use of surface electromyography in dysphagia evaluation
(2017-01-01)
Wang, Yao-Chin
;
Chou, Willy
;
Lin, Bor-Shing
;
Wang, Jhi-Joung
;
Lin, Bor-Shyh
Dysphagic patients usually have a variety of clinical problems such as malnutrition, significant weight loss, and aspiration pneumonia. Dysphagia is a complication commonly caused by strokes, and surface electromyography (sEMG) provides a simple, non-radioactive, and non-invasive method to measure the patterns of muscle activity during swallowing, allowing clinicians to describe the physiology of swallowing behavior. Most previous studies have described swallowing behavior in terms of amplitude and duration. However, there is no objective and precise approach available for the evaluation of swallowing coordination. In order to evaluate swallowing coordination more precisely, a wireless and wearable monitoring device for dysphagia evaluation was designed for the present study in order to measure four muscle groups simultaneously during swallowing. In this context, the variations of the cross-correlation coefficients were defined as the discoordination index, a metric which can effectively reflect the differences between the surface EMG patterns of the bilateral muscle groups. The experimental results of this study show that the discoordination indices for dysphagic patients are significantly larger than those for healthy subjects and that these discoordination indices can be used as an effective means of evaluating the coordination between bilateral swallowing muscles.