Browsing by Author "Hsieh, Yao-Fang"

Now showing 1 - 14 of 14

An image based optical lens eccentric error inspection system
(2012)
Chen, Yung-Hsiang
;
Hsieh, Yao-Fang
;
Hsu, Chia-Wei
;
Ou-Yang, Mang
;
Lee, Cheng-Chung
In this study, we have presented the prototype of optical lens eccentric error inspection system based on image processing algorithms. The traditional inspection by using the transmission or reflection measurements is limited to the geometry and size of the lens. In this study, an image based inspection system has developed target on fast, accurate and low-cost to meet the need for lens eccentric error inspection.
Analyze fluorescent characteristic of cancer cell using hyperspectroscopic imaging system (HIS)
(2012-01-01)
Hsieh, Yao-Fang
;
Chen, Chih-Hsien
;
Mang, Ou-Yang
;
Duann, Jeng-Ren
;
Chiou, Jin-Chern
Currently, the cancer was examined by diagnosing the pathological changes of tumor. If the examination of cancer can diagnose the tumor before the cell occur the pathological changes, the cure rate of cancer will increase. This research develops a human-machine interface for hyper-spectral microscope. The hyper-spectral microscope can scan the specific area of cell and records the data of spectrum and intensity. These data is helpful to diagnose tumor. This study finds the hyper-spectral imaging have two higher intensity points at 550nm and 700nm, and one lower point at 640nm between the two higher points. For analyzing the hyper-spectral imaging, the intensity at the 550nm peak divided by the intensity at 700nm peak. Finally, we determine the accuracy of detection by Gaussian distribution. The accuracy of detecting normal cells achieves 89%, and the accuracy of cancer cells achieves 81%.
Biopsy Diagnosis of Oral Carcinoma by the Combination of Morphological and Spectral Methods Based on Embedded Relay Lens Microscopic Hyperspectral Imaging System
(2015-08-01)
Ou-Yang, Mang
;
Hsieh, Yao-Fang
;
Lee, Cheng-Chung
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
Cytopathological examination through biopsy is very important for carcinoma detection. The embedded relay lens microscopic hyperspectral imaging system (ERL-MHIS) provides a morphological image of a biopsy sample and the spectrum of each pixel in the image simultaneously. Based on the ERL-MHIS, this work develops morphological and spectral methods to diagnose oral carcinoma biopsy. In morphological discrimination, the fractal dimension method is applied to differentiate between normal and abnormal tissues. In spectral identification, normal and cancerous cells are distinguished using five methods. However, the spectra of normal and cancerous cells vary with patient. The diagnostic performances of the five methods are thus not ideal. Hence, the proposed cocktail approach is used to determine the effectiveness of the spectral methods in correlating with the sampling conditions. And then we use a combination of effective spectral methods according to the sample conditions for diagnosing a sample. A total of 68 biopsies from 34 patients are analyzed using the ERL-MHIS. The results demonstrate a sensitivity of 90 +/- 4.53 % and a specificity of 87.8 +/- 5.21 %. Furthermore, in our survey, this system is the first time utilized to study oral carcinoma biopsies.
Determination of optimal converting point of color temperature conversion complied with ANSI C78. 377 for indoor solid-state lighting and display applications
(2012-08-27)
Hsieh, Yao-Fang
;
Ou-Yang, Mang
;
Huang, Ting-Wei
;
Lee, Cheng-Chung
;
電機資訊學士班
In recent years, displays and lighting require color temperature (CT) conversion function because observers have different preferences. This paper proposes effective methods to determine the optimal converting point of CT conversion for display and lighting application. For display application, the concepts of center of gravity and isotemperature line are applied to determine the optimal converting point. The maximal enhancement of luminance between the optimal and average is 18%. For lighting application, this paper proposes two methods to determine the optimal converting point in the CT quadrangle which complies with ANSI C78. 377. The enhancement of luminance in two CT modes (5700K and 6500K) are 14.2% and 23.6%, respectively. (C) 2012 Optical Society of America
Establish a six-primary color display without pixel-distortion and brightness loss
(2008-01-01)
Hsieh, Yao-Fang
;
Chuang, Ming-Chuen
;
Ou-Yang, Mang
;
Huang, Shih-Wei
;
Li, Jia Hao
Recently, color reproduction stages are developed greatly, such as liquid-crystal displays, LCD TV, LCD projectors, DLP projectors, and etc. Wide-color-gamut displays are distinguishing feature of many display manufacturers. Many researches about multi-primary color displays are proposed, but there are still some problems which are not solved. This study proposed a novel multi-primary projection display system using two projectors. One of the two projectors is modified by changing two dichroic mirrors inside. The modified projector is combined with the other to a new six-primary color display. This study applies equal-luminance boundary theorem to construct gamut volume and evaluates the merit between gamut volume and brightness. By this method, the cut-off wavelength of dichroic mirrors can be found out. In the past, to align the images of the two projectors is pre-distorted to compensate the trapezoidal distortion. This study proposes to eliminate trapezoidal distortion by using the offset of the projector. This study directly changes dichroic mirrors to maintain the brightness and contrast, and solves lower brightness and contrast resulted from adding filters before. Additionally, this study uses a reflection mirror to twist projection path and also constructs a stage to align projection images more accurately.
Estimation of spectral radiance on a tristimulus color sensor system illuminated under two light sources
(2015-01-01)
Mang, Ou-Yang
;
Hsieh, Yao-Fang
;
Lee, Cheng-Chung
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
The tristimulus color sensor system, a trichromatic camera, is developed to estimate the spectral radiance of objects. However, since the spectral sensitivity of the system does not match the Commission International de l\'Eclairage (CIE) 1931 color matching function, it yields inaccurate colorimetric and spectral information. This work proposes methods using two light sources for estimating accurate spectral radiance and verifies that the accuracy achieved using these two illuminant methods exceeds that achieved using single illuminant methods. The two illuminant methods successfully reduce the mean color difference in CIELAB from 31.24 to 0.8 and provide a spectral accuracy of 0.0103. Furthermore, a tristimulus color sensor system is developed to verify the performance of these methods. (C) 2015 Elsevier GmbH. All rights reserved.
Finite conjugate embedded relay lens hyperspectral imaging system (ERL-HIS)
(2011-11-20)
Hsieh, Yao-Fang
;
Ou-Yang, Mang
;
Lee, Cheng-Chung
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We present a novel embedded relay lens hyperspectral imaging system (ERL-HIS) with high spectral resolution (nominal spectral resolution of 2.8 nm) and spatial resolution (30 mu m x 8 mu m) that transfers the scanning plane to an additional imaging plane through the internal relay lens so as to alleviate all outside moving parts for the scanning mechanism used in the traditional HIS, where image scanning is achieved by the relative movement between the object and hyperspectrometer. The ERL-HIS also enables high-speed scanning and can attach to a variety of optical modules for versatile applications. Here, we also demonstrate an application of the proposed ERL-HIS attached to a microscopic system for observing autofluorescent images of sliced cancer tissue samples. (C) 2011 Optical Society of America
Optimize Maximal Brightness and Correlated Color Temperature for Multi-primary color displays
(2009-01-01)
Ou-Yang, Mang
;
Huang, Ting-Wei
;
Hsieh, Yao-Fang
;
Kuo, Yi-Ting
;
應用藝術研究所
Color temperature(CT) conversion of triprimary color display from one white point to another on the Planckian's locus with the maximal brightness has been proposed. However, whether converting an original white point to another white point on the isotemperature line will enlarge maximal brightness more than converting an original white point to another white point on the Planckian's locus needs to be determined. This paper proposes a new algorithm to enlarge maximal brightness by calling the center of gravity method of color mixing in the acceptable color difference range while the CT is converted. From the prior study, we find that the apexes of color gamut boundary move along the line of center gravity of primaries while the total brightness varies, where the line of center gravity of primaries is linked by the color points mixed by two or more full primary colors and one partial primary color. And in CIE 1931 color space, the color gamut boundary expanding from white point as total brightness decreasing will touch the isotemperature line with its apexes. Therefore, the best point of CT conversion of tri-primary color display with more maximal brightness is determined by the isotemperature line and the line of center gravity of primaries. Further, the theory extends to multi-primary color displays. Lastly, the simulations prove that converting a white point to another on the isotemperature line enlarges maximal brightness more than converting a white point to another on Planck's locus.
Portable LED-induced autofluorescence spectroscopy for oral cancer diagnosis
(2017-04-01)
Yan, Yung-Jhe
;
Huang, Ting-Wei
;
Cheng, Nai-Lun
;
Hsieh, Yao-Fang
;
Tsai, Ming-Hsui
Oral cancer is a serious and growing problem in many developing and developed countries. To improve the cancer screening procedure, we developed a portable light-emitting-diode (LED)-induced autofluorescence (LIAF) imager that contains two wavelength LED excitation light sources and multiple filters to capture ex vivo oral tissue autofluorescence images. Compared with conventional means of oral cancer diagnosis, the LIAF imager is a handier, faster, and more highly reliable solution. The compact design with a tiny probe allows clinicians to easily observe autofluorescence images of hidden areas located in concave deep oral cavities. The ex vivo trials conducted in Taiwan present the design and prototype of the portable LIAF imager used for analyzing 31 patients with 221 measurement points. Using the normalized factor of normal tissues under the excitation source with 365 nm of the central wavelength and without the bandpass filter, the results revealed that the sensitivity was larger than 84%, the specificity was not smaller than over 76%, the accuracy was about 80%, and the area under curve of the receiver operating characteristic (ROC) was achieved at about 87%, respectively. The fact shows the LIAF spectroscopy has the possibilities of ex vivo diagnosis and noninvasive examinations for oral cancer. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Portable noninvasive system for oral cancer diagnosis
(2012)
Yang, Chin-Siang
;
Ou-Yang, Mang
;
Hsieh, Yao-Fang
;
Chen, Yu-Ta
;
Chiou, Jin-Chern
This study presents a portable noninvasive detection system which can get the image of specific spectral immediately, that promote to oral cancer diagnosis. According to research literature show the performance called autofluorescence of cells after exciting by specific wave band of light. It is different of the spectrum distribution for lesions of epithelial cells and normal cells after fluorescence excite, that is a basis of diagnosing to oral cancer. The convenient equipment for detection of oral cancer is modified for existing handheld microscope. From Fig. 1, the UV LED illuminates to the surface of object and excites the cells which produce fluorescent reaction and showed the image with specific wavelength. The image passes through the central channel and filter out unwanted spectral by the selection of filter, and focused by the focus lens on the image sensor, therefore we can achieve the specific wavelength image via fluorescence reaction.
Research of Color Distribution Index in CIEL*a*b* Color Space
(2010)
Jeng, Wei-De
;
Huang, Ting-Wei
;
Mang Ou-Yang
;
Lee, Tsang-Hsing
;
Hsieh, Yao-Fang
The index for evaluating the ability of color reproduction is required. The color distribution index (CDI) was proposed to comment the display ability of color distribution of reproduction in CIE Lu'v' color space. A cell of Just Noticeable Difference (JND) for luminance and chromaticity (u'v') was proposed to qualify whether the reproduced colors are in some region of color volume of display. Human eye can perceive fewer colors at low luminance, however, the scalar of chromaticity (u'v') JND at low luminance was the same with the one at other luminance. CDI will be distorted at low luminance. In this paper, regarding perceptible vision at low luminance, we try to use chromaticity (a*b*) JND to replace chromaticity (u'v') JND. The color distribution will be discussed in CIE La*b* color space. We find that CDI at low luminance in CIE L*a*b* color space is higher than in CIE Lu'v' color space, as well as different gamma curves and different bit depths affect CDI. The displays are going to keep approaching 100% true color reproduction; hence the index for evaluating the ability of color reproduction is required.
Research of the chromaticity coordinates and color spectrum calibration using tristimulus sensors and eigenspectrum method
(2009-01-01)
Ou-Yang, Mang
;
Huang, Ting-Wei
;
Hsieh, Yao-Fang
;
Kuob, Yi-Ting
;
應用藝術研究所
The purpose of color measuring instrument is judging the color information by scientific method, which may instead of the human's eyes. Generally, the instruments of color measuring have two kinds, spectrophotometer and color meter. The former measures spectrum by usage of prism or grating to separate the light, this could achieve high accuracy but with a higher price. The latter obtains tristimulus from color filter; however there is no spectrum information with it. This article establishes a color measuring system and uses eigenspectrum method to correct the average inaccuracy. The measuring system includes tristimulus sensors which were made by color filter, and Xenon lamp as light source. The advantage of this measuring system is the higher accuracy and the lower cost. The eigenspectrum method can correct the average inaccuracy in less eigenvector, which can save the time. This method used singular value deposition to obtain basis function of spectrum set, which can be obtained by measuring. Because the range of the spectrum set was 380nm to 780nm, the eigenvector per nanometer from 380nm to 780nm can be obtained. In general, the color spectrum can be obtained with less eigenvector. This article establishes a color measuring system, which has three sensors and uses Xenon lamp as light source, to acquire the color spectral reflectance. This article also uses the eigenspectrum methods to correct the average color difference in L*a*b* color space, which from 31.2398 down to 4.8401, and reconstructs the spectrum information.
The chromaticity coordinates and color spectrum calibration using tri-stimulus sensors and double light sources
(2010-01-01)
Hsieh, Yao-Fang
;
Huang, Ting-Wei
;
Ou-Yang, Mang
;
Kuob, Yi-Ting
;
電子工程學系及電子研究所
Generally, the instrument of color measurement can be divided into spectrophotometer and color meter. The former instrument use prism or grating to separate the light, it can achieve high accuracy but a higher price. The latter instrument use color filter, however there is no spectrum information with it. This article establishes a color measuring system and uses eigen-spectrum method in double light sources to calibrate the spectrum. The measuring system includes tri-stimulus sensors which were made by color filter. The tungsten lamp and Xenon lamp are used to be light source. The advantage of this measuring system is the higher accuracy and the lower cost. The eigen-spectrum method can calibrate the spectrum in less eigenvector. This method used singular value deposition to obtain basis function of spectrum set, which can be obtained by measuring. Because the range of the spectrum set was 380nm to 780nm, the eigenvector per nanometer from 380nm to 780nm can be obtained. In general, the color spectrum can be obtained with less eigenvector. The color difference in L*a*b* color space from 31.2398 down to 2.48841, and reconstructs the spectrum information.
The new hyperspectral microscopic system for cancer diagnosis
(2011-01-01)
Hsieh, Yao-Fang
;
Mang, Ou-Yang
;
Chiou, Jin-Chern
;
Lin, Yung-Jiun
;
Tsai, Ming-Hsui
Until now, the cancer was examined by diagnosing the pathological changes of tumor. If the examination of cancer can diagnose the tumor before the cell occur the pathological changes, the cure rate of cancer will increase. This research develops a human-machine interface for hyper-spectral microscope. The hyper-spectral microscope can scan the specific area of cell and records the data of spectrum and intensity. These data is helpful to diagnose tumor. This research aims to develop a new system and a human-machine interface to control the hyper-spectral microscope. The interface can control the moving speed of motor, the exposure-time of hyper-spectrum, real-time focus, image of fluorescence, and record the data of spectral intensity and position.