• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
• /
• pp.380-383
• /
• 2007

In this research, we present color filter which is patterned by screen printing method. Analysis of screen printing process, screen printing system, experiment for uniform printing in large area, characteristics of screen printed CF are investigated .In spite of limitation of precision, screen printed color filter is very cost- effective in respect of manufacturing facility and ink usage.

• 한국전자파학회:학술대회논문집
• /
• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
• /
• pp.47-53
• /
• 2003

Screen filter of PDP TV plays an important role in satisfying the EMI/EMC specifications. Two types of filters, the mesh type and the sputter type, are used in PDP TVs, and this paper presents measurement results of the shielding effectiveness (SE) in the frequency range from 50MHz to 1GHz. Two methods were used for the measurement, one using network analyzer (NA) in an open area test site(OATS), and the other using the screen room. The overall conclusion is that the shielding effectiveness of the screen filter is related to the surface resistance of the screen filter. The mesh type screen filters are superior to the sputter types in the shielding effectiveness, which is varying with the frequency.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
• /
• pp.568-570
• /
• 2004

A shielding effectiveness of mesh screen filter of plasma display panel (PDP) has been calculated in this paper. Since the screen filter is located near the radiation source, the near field wave impedance of the radiation source, i.e., the PDP electrodes, has been considered to calculate the shielding effectiveness. The near field shielding effectiveness of screen filter at 30${\sim}$300 MHz has been estimated to be more than 65${\sim}$80 dB. The measured shielding effectiveness of screen filter is 10${\sim}$50 dB at 30${\sim}$300 MHz[1]. The resulting discrepancy indicates that there are other EMI emission sources such as emission from PCB and cable besides the PDP electrodes.

• 한국산업융합학회 논문집
• /
• 제25권2_2호
• /
• pp.263-269
• /
• 2022

In this study, the optimal support position determination and stability determination of the wedge wire screen were performed for the production of the wedge wire filter screen with improved mesh screen. In order to manufacture a filter screen using a wedge wire, the support rod wedge wire is first installed according to the filtering capacity, and then spot welding is performed while rotating the profile wire. In the existing manufacturing method, it was manufactured using a 3m rod wedge wire and then cut according to dimensions, but it required the manufacture of a 6m cylindrical screen. Due to the increase in wedge wire length, it is difficult to manufacture stress concentration at sagging and fixed positions. In order to shorten the time of analysis, a single wedge wire was applied instead of a plurality of wedge wires. The reliability and validity of the interpretation were presented and the results were derived. After selecting the support point at the 2m position, structural analysis was performed on the entire filter screen to confirm stability.The purpose of this study is to identify the maximum deflection of the wire for the production of a 6m wedge wire screen and secure design basic data so that it can work safely through optimal support.

• 대한전자공학회논문지SD
• /
• 제45권9호
• /
• pp.14-20
• /
• 2008

최근 LCD나 PDP와 같은 Slim 평판디스플레이의 급속한 성장에 대응하기 위하여, 기존의 부피가 큰 CRT의 두께 축소를 위한 광각화 기술이 요구 되어 지고 있다. 그러나 이러한 광각화한 Screen을 가진 CRT를 만드는 데는 많은 문제점이 있다. 특히 Screen의 Black Matrix를 형성함에 있어서, 설계자의 의도 대비 과도하게 형성되거나, 미형성 되는 큰 문제가 발생한다. 이러한 문제는 광각화 됨으로 인하여 민감도가 증가하여 발생하게 된다. 이러한 부분을 해결하기 위해서 본 논문에서는 새로운 filter system을 제안한다. 기존에 사용하던 filter to panel 방식에서 panel to filter control 방식을 사용함으로써, 설계자의 의도대로 쉽게 Black Matrix를 조절할 수 있다. 본 논문은 새로운 광각화된 CRT에서 좀 더 나은 screen품질을 확보할 수 있도록 새로운 귄ter design 방법을 제안한다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제11권1호
• /
• pp.17-23
• /
• 1988

As the reutilizing method of exhausted screen, authors used it as a filter and compared with the aluminium filtration. The results are as followed; 1. One sheet of gadolinium front screen has the same radiation absorption as $2.8{\sim}3.3\;mm$ Al equivalent and regular tungsten screen $2.3{\sim}2.7mm$ Al. 2. HVL after Gd-screen filtration was less than the values after aluminium and tungsten-screen filtration. And, image definition with Gd-screen filtration was better than other two cases. Ana surface dose to produce a same film density was more than other two cases. It will be very useful to apply, Gd-screen filter in clinics as it has no deficiency of image quality.

• 한국인쇄학회지
• /
• 제13권1호
• /
• pp.13-24
• /
• 1995

The color filter os made in four methods ; dyeing, printing electrodisposition and pigment dispersed method. Among technologies for color filter manufacture, pigment-dispersed and hybrid method are dominant over all others in commercial manufacture of large scale, fine resolution color filter for liquid crystal display. In this paper to investigate the possibility of the color filter manufacture for LCD by screen printing method, we synthesyzed PVA/sbQ screen emulation for high resolution, estimated image of printed fine pattern and manufactured color filter by screen printing. Results of the study are as follow and found the screen printing method os useful and valid from it. 1. Fine pattern is formed due to photocyclodomerization of -C=C- bond at 342nm, on the other hand unexposured parts are removed in water. 2. sharpness and resolution of fine pattern is improved at mesh streching angle 22.5 and 45 than 0 degree. It is expected due to resistance between inks and mesh streching angles. 3. Spectral characteristics of sample inks were R(640nm), G(535nm), B(470nm), transmittance were R(92%), G(79%), B(70%) and chromaticity coordinate values were R(0.62,0.33), G(0.32,0.59), B(0.14,0.17)

• 반도체디스플레이기술학회지
• /
• 제22권3호
• /
• pp.28-35
• /
• 2023

Moiré patterns emerge due to the interference between the non-emission area of the LED screen and the grid line in an image sensor of a video recording device when taking a video in the presence of the LED screen. To reduce the moiré intensity, we have fabricated an anti-moiré filter using hollow glass microspheres (HGMs) by slot-die coating. The LED screen has a large non-emission area because of a large pitch (distance between LED chips), causing more severe moiré phenomenon, compared with a display panel having a very narrow black matrix (BM). It is shown that HGMs diffuse light in such a way that the periodicity of the screen is broken and thus the moiré intensity weakens. To quantitatively analyze its moiré suppression capability, we have calculated the spatial frequencies of the moiré fringes using fast Fourier transform. It is addressed that the moiré phenomenon is suppressed and thus the amplitude of each discrete spatial frequency term is reduced as the HGM concentration is increased. Using the filter with the HGM concentration of 9 wt%, the moiré fringes appeared depending sensitively on the distance between the LED screen and the camera are almost completely removed and the visibility of a nature image is enhanced at a sacrifice of luminance.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2010년도 춘계학술대회
• /
• pp.291-294
• /
• 2010

여러 가지 형태의 동영상을 재생하기 위해서는 특정 디코더 및 Demux가 필요하다. 필요에 따라, 많은 개발자들이 필터 개발을 하고 있지만, 기존의 GOM플레이어나 KMP플레이어는 API가 Open되어있지 않아, 작성된 필터 사용의 어려움이 있고, 동영상 재생에 사용되는 Codec의 선택에 대한 문제점이 있다. 본 논문에서는 작성된 필터를 이용하여, 손쉽게 플레이할 수 있는 라이브러리를 개발하며, 화면을 찾기 위한 Seek기능을 설계하고, 화면캡처, 전체화면, 재생화면, 확대, 축소 등 사용자 편의성을 위한 DLL파일로 구축하여 개발한다. 본 연구는 멀티미디어 제작 S/W기술과 정보통신 발전에 기여 할 것이다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제15권1호
• /
• pp.65-78
• /
• 1992

Routine chest radiography is generally imaged by high voltage technique but some radiological technologists use low voltage for imaging. High voltage is usually said between $120\;kV{\sim}140\;kV$. Some RTs like using heavy filtration but others seldom like using it. However which is better for use calcium tungustate film screen system or ortho system and high contrast film or wide latitude c-type film for the exculusive use of chest radiography. We could not make a decision which is ideal method for use. In my opinion any method is not always exellent for chest radiography. In my experiments that I had at Kaken hospital in Japan last year I expect to keep the balance between image quality and diagnostic range and to reduce radiation dose for patients. My experiments are as follows. 1. We have looked into system characteristics(speed and contrast) in accordance with kVp($80{\sim}140$) and added filter($no{\sim}1/16\;VL$) in three screen film systems(BX3+CRONEX4, SRO750+MGH, SRO750+MGL). 2. We have looked into skin dose and film dose with same D=1.8 lung field density in accordance with kVp($80{\sim}140$) and added filter($no{\sim}1/16\;VL$) in three screen film systems. 3. We have compared with the evaluation between correlation of physical image quality(MTF) and optical diagnostic capability. Result are follows. 1. Speed of BX3+CRONEX4 became higher in accodance with kVp and thickness of filter but speed of ortho system was not as like regular system. Thicker filter diminished the speed over 100 kV range in SRO750+MGL. In case of SRO750+MGH speed of 1/16VL filter was looked into lower than speed of 1/4VL filter. Sensitivity of ortho system depends on tube voltage and added filter. 2. Skin dose has been detected $225\;{\mu}Gy{\sim}66\;{\mu}Gy$ in BX3+CRONEX4 from 80 kV, no filter to 140 kV, 1/16VL filter. SRO750+MGH could reduce the patient dose $1/2{\sim}1/3$ level in comparison to that of BX3+CRONEX4. 3. The higher kV was the worse MTF became the thicker filter was the worse MTF became too. MTF of BX3+CRONEX4 was detected better than MTF of SRO750+MGH but SRO750+MGH's optical detectability of small lesion in lung field came out better than that of BX3+CRONEX4. Conclusion Recently routine chest radiography is generally imaged by high voltage but it seems to be there are some questions in using of film screen combination. In high voltage chest radiography the subject contrast will come down that means latitude become wider. In this case if we select the low contrast film screen system(C or L type) the film contrast will fall down extremly and detectability of small lesion will be deteriorated. Wide latitude C, L type film has a merit of high detectability on mediastinum. Furthermore high contrast film screen system has the advantage to keep the high contrast in low density region as like mediastinum and heart shadow. Therefore in low subject contrast high voltage chest radiography we would rather choose the high contrast film screen system(H type) I think. From a view point of patient dose detectability of mediastinum and lung field. The optimum technical facter was found out 120 kV, 1/16VL filter : BX3+CRONEX4, 140 kV, 1/4VL filter : SRO750+MGH, 100 kV, 1/4VL filter : SRO750+MGL.