• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.6
• /
• pp.487-493
• /
• 2004

In this Paper, we propose a lighting system for the stable detection of check defects of the CRT panel through the analysis of the lighting interaction between the lighting unit and the CRT panel. The check defect is very difficult to detect reliably because of its high sensitivity according to the direction of incident light. At first, we model the physical shape of check defects using SEM image. And then we apply physics based illumination model to investigate the optical characteristics of the check defect. Finally, we propose a lighting system for the stable detection of check defect. Experimental results show the feasibility of the proposed lighting system for check inspection.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.23 no.7
• /
• pp.172-180
• /
• 2019

In this study, the microstructure and gamma-ray shielding efficiency of CRT glass mortar specimen were evaluated with replacement ratio and material properties. The results show that as the replacement ratio of CRT waste glass increases, the volume of pores with diameters below 50 nm and above 400 nm is increased. Also, the half-value layer of CRT glass mortar decreased with the increasing of linear attenuation coefficient. In addition, compressive and flexural strength were reduced when CRT waste glass was replaced as the fine aggregate, but the mechanical performance of CRT mortar specimen could be obtained by substitution of the mineral admixture.

• Journal of the Ergonomics Society of Korea
• /
• v.20 no.2
• /
• pp.59-70
• /
• 2001

White uniformity is one of the important inspection factors determining the image quality of CRT screen. In the full white pattern, white uniformity means the degree of uniform distribution of white color across the whole screen. To elicit the sensitivity factors affecting the decision of the white uniformity quality, experiments in which participants were confronted with 6 evaluation points embedded in 3 measurement groups on a CRT screen were conducted to gather the psychophysical data that are the level of white uniformity subjects perceived and CA100 produced. These data were used to develop a modified CIE1976 equation for calculating white uniformity. Performance comparison between the original CIE1976 equation and the modified equation was conducted in terms of accuracy test and magnitude estimation. It was concluded the modified equation is more sensitive in the change of white uniformity, compared to the original CIE1976 equation.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.23 no.1
• /
• pp.163-170
• /
• 2019

In recent years, various types of industrial wastes are rapidly increasing with the development of high-tech industries. Specially, high-density waste glass of CRT TV containing heavy metals are buried or disposed of due to reprocessing costs and environmental pollution problems. Thus, more basic research is needed to recycle waste such as CRT waste glass such. In this study, the fundamental properties and radiation shielding performance of mortar specimens substituted CRT waste glass as a fine aggregate were analyzed and their application to shielding materials was evaluated. According to the results, the bulk density of mortar specimen replaced with CRT waste glass was increased and the compressive strength and flexural strength were decreased. Meanwhile, the CRT waste glass substitute specimen containing a large amount of lead component showed a higher shielding performance than the general mortar specimen. Especially, the linear attenuation coefficient of CRT waste glass in $122KeV{\cdot}^{57}Co$ of the low energy field was 2.5 times higher than that of normal specimen.

• Journal of Korean Society for Quality Management
• /
• v.29 no.3
• /
• pp.124-137
• /
• 2001

In general, it is very efficient and effective to use screening variables that are correlated with the performance variable in case that measuring the performance variable is impossible (destructive) or expensive. The general methodology for searching surrogate variables is regression analysis. This paper considers the inspection problem in CRT (Cathode Ray Tube) production line, in which the performance variable (dependent variable) is binary type and screening variables are continuous. The general regression with dummy variable, discriminant analysis and binary logistic regression are considered. The cost model is also formulated to determine economically inspection procedure with screening variables.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.18 no.35
• /
• pp.1-8
• /
• 1995

Automatic inspection system software for display image characteristic of CRT is developed. There are two major contributions of this software development. One is that the data from measuring equipments which was usually collected manually is automatically collected through RS-232C port and is saved in computer, then, trend analysis graph and final reports are generated. The other is that evauation of characteristic of electron gun was automatically processed by CCD camera and image processing technique. The system is developed under MS-Windows environment utilizing Borland C++4.0 Compiler and DT 3852-8 image processor board. This system can save the time and man power to measure and to anayze the image characteristics relative to current method.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.10
• /
• pp.28-34
• /
• 1997

This paper describes an automatic measurement method for the in-line inspection of assembly tolerances of cathod ray electron guns. The method uses an optical microscope with a CCD camera as a probe. An automatic gap recognition algorthm with digital image processing and a new software autofocus algorithm based on using an optimal edge detector have been developed to improve the measuring accuracy. An inspection system has been proposed and practically implemented for in-line inspection to a real factory automation line. The inspection system consists of a gap inspection part and an eyelet. Total time consumed for inspecting all measuring items is about 10 seconds and the repeatability is below .+-. 5 .mu. m

• The Transactions of the Korea Information Processing Society
• /
• v.3 no.4
• /
• pp.1014-1025
• /
• 1996

The magnetizer that is magnetizing the magnet which is used for RGB (Red Green Blue) control of CRT(Cath-ode-Ray Tube)and the magnet inspection unit which is used for test the state of magnetizing have been imported by magnet manufactures up to now. They are operation by manual now, so that they are needed lots of time and have an increase in probability of malefunction by operator. In this study, we have developed a united system from the magnet production process to inspection ork to automaized a entire progress. Therefor, as we are testing the status of every work and analyzing exactly the distribution in quality with this system, we have known that the reliability of magnetization and magnetized status test has not only increased, but the rate of inferior quality almost not generated.

• Journal of Institute of Control, Robotics and Systems
• /
• v.2 no.1
• /
• pp.26-34
• /
• 1996

One of the challenging tasks in visual inspection using CCD camera is to identify surface defects in an image with complex textured backgeound. In microscopic view, the surface of real objects shows regular or random textured patterns. In this paper, we present a visual inspection algorithm to extract abnormal surface defects in an image with textured background. The algorithm uses the space and frequency information at the same time by introducing the Dominant Frequency Map(DFM) which can describe the frequency characteristics of every small local region of an input image. We demonstrate the feasibility and effectiveness of the method through a series of real experiments for a 14" TV CRT mold. The method successfully identifies a variety of infinitesimal defects, whose size is larger than $50\mu\textrm{m}$, of the mold. The experimental results show that the DFM based method is less sensitive to the environmental changes, such as illumination and defocusing, than conventional vision techniques.ques.

• Journal of the Korean Society of Radiology
• /
• v.13 no.2
• /
• pp.209-216
• /
• 2019

The purpose of this study was to suggest the optimum ambient illumination level for proper visualization in image inspection and reading on CRT and LCD monitors used for ultrasound and reading. The evaluators were divided into 4 groups: 20 (Ultra-sonographer: 20 groups (4 groups: ultra-sonographer, 1-5 years, 5 ultra-sonographers, 6 to 10 years, 5 ultra-sonographers, 11 to 15 years, The subjects were 32 questions. The evaluation method was image evaluation of ultrasonic soft copy images for 30 seconds per 10, 25, 100Lux ambient illumination. The evaluation results were evaluated as 6 points (Normal = Definitely no lesion), 2 points = possibly not a lesion, 3 points = probably not a lesion, 4 points = possibly a lesion, 5 points = probably a lesion, 6 points = Definitely a lesion). In this study, the results of ROC analysis according to ambient light illumination reading softcopy images used for lesion detection of all ultrasound images showed the highest sensitivity, specificity, and AUC results at 10Lux. It was found that optimal use of 10Lux for ambient light illumination would provide optimal detection of lesions in ultrasound soft copy images. Based on the future research data, it will be presented as basic data for designing ambient light brightness of ultrasound imaging laboratory and reading room.