• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.808-811
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• 2007

Aspheric glass lens have recently been used in camera phone module because they are more effective than spherical ones. In this paper, the grinding condition of the tungsten carbide molding core has been found after applying DOE to the development of the aspheric glass lens for the 3 Megapixel and 2.5x camera-phone module. Also, the ultra precision grinding process was investigated under this condition by experiment. Re-Ir coating was applied on the ground surface of the tungsten carbide molding core. The influence of Re-Ir coating on the form accuracy and surface roughness of molding core was compared and evaluated. The form accuracy and surface roughness of the molding core were improved by application of Re-Ir coating on the surface of the tungsten carbide molding core.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.8
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• pp.720-725
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• 2007

This study investigated the pressing conditions in the molding of aspheric glass lenses for the mega pixel phone camera module using the DOE method. Tungsten carbide (WC; Japan, Everloy Co., 002K),which contained 0.5 w% cobalt (Co), was used to build the mold. The mold surface was ultra-precision ground and polished, and its form accuracy (PV) was 0.85um in aspheric surface. We selected four factors, pressing temperature, force and time of first step, and force of second step, respectively, as the parameters of the pressing process. in order to reduce the number of experiments, we applied fractional factorial design considering the main effects and two-way interactions. The analysis results indicate that the only two main effects, the pressing temperature and the time of pressing step 1, are available for the form accuracy (PV) of the molded lens. The analysis results indicated that the best combination of the factors for lowering the form accuracy(PV) value of molded lens was to have them at their low levels.

• Korean Journal of Optics and Photonics
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• v.18 no.1
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• pp.31-36
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• 2007

In order to evaluate the performance of phone camera lenses, we have developed equipment for measuring the modulation transfer function(MTF) for small size lenses. The equipment is composed of an an image analyzer, object generator, and a lens mount. The object generator is rotated for on and off-axis measurement. The lens mount is of horizontal type and tiltable for precise alignment to the optical axis. After the initial alignment process, the measurement is done within 10 seconds automatically

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.447-448
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• 2007

Product development is consisting by trend that accommodate almost function digital cam in camera phone that can speak of Mobile appliance, and competition about number of elemental area of image sensor is consisting for market prior occupation between these. Propose in this research and small size camera phone self-focusing adjustment actuator that do city manufacture is similar with general storehouse pickup actuator drive way, but selected in cylindrical to reduce space that lens holder occupies because there is restriction loading of lens and space enemy. Target number of research established that execute drive displacement more than $600{\mu}m$ in 2.75V that is house voltage that is used in Mobile device that is general. Also, described about maximum transfer displacement characteristic, displacement response characteristic, hysteresis, response characteristic, smallest transfer step characteristic, actuator's drive characteristic that is manufactured to examination item of maximum consumption electric power by special quality estimation system that apply laser displacement sensor that produce itself to evaluate city manufactured actuator's special quality.

• Current Optics and Photonics
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• v.7 no.3
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• pp.273-282
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• 2023

This paper presents a new method for redistributing effectively the first orders of each lens element to achromatize and athermalize an optical system, by introducing a novel method for adjusting the slope of an achromatic and athermal line. This line is specified by connecting the housing, equivalent single lens, and aberration-corrected point on a glass map composed of available plastic and glass materials for molding. Thus, if a specific lens is replaced with the material characterized by the chromatic and thermal powers of an aberration-corrected point, we obtain an achromatic and athermal system. First, we identify two materials that yield the minimum and maximum slopes of the line from a housing coordinate, which specifies the slope range of the line spanning the available materials on a glass map. Next, redistributing the optical first orders (optical powers and paraxial ray heights) of lens elements by moving the achromatic and athermal line into the available slope range of materials yields a good achromatic and athermal design. Applying this concept to design a mobile-phone camera lens, we efficiently obtain an achromatic and athermal system with cost-effective material selection, over the specified temperature and waveband ranges.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.465-469
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• 2008

Mobile phone becomes composite product which the high technological multimedia functions of a Digital camera, MP3, MP4, Blue-tooth, DMB over basic functions of a calling and 3M3. By the view of user, many functions give a heavy burden rather than supporting convenient function itself because it is complex for user to use it. We want to evaluate how users feel using mobile phone according to age, comparing use frequency and necessity. So survey is tried to figure out the difference between use frequency and necessity by dividing three groups into 20s and 30s and 50s. As a result, difference of use frequency and necessity for functions of mobile phone between 20s and 30s and 50s. And the other users have the difference. Consequently, mobile phone development according to age is necessary to satisfy user's desire, evaluating elements research of user preference. We hope this paper can contribute to mobile phone development as a basic guidance.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.93-98
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• 2011

In this paper, we propose the surveillance and combat robot framework for remote monitoring and robot control on the smart phone, which is implemented with the fusion technology called RITS(Robot technology & Information Technology System). In our implemented system, the camera phone mounted on the robot generates signals to control the robot and sends images to the smart phone of the operator. Therefore, we can monitor the surrounding area of the robot with the smart phone. Besides the control of the movement of the robot, we can fire the weapons armed on the robot by sending the fire command. From experimental results, we can conclude that it's possible to control the robot and monitor the surrounding area of the robot and fire the weapons in real time in the region where the 3G(Generation) mobile communication is possible. In addition, we controlled the robot using the 2G mobile communication or wired phone when the robot is in the visual range.

• Korean Journal of Community Nutrition
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• v.16 no.6
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• pp.697-705
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• 2011

This study was conducted to investigate the effects of real time communication digital photography method using Kakao Talk application in smart-phone for the fortification of food consumption monitoring and weight reduction. Thirty-four female college students were randomly assigned to the camera-phone (CP) group or smart-phone (SP) group. Each group participated in the weight control program for 8 weeks. The mean energy intake of CP group during program was 1353.5 kcal and the SP group consumed 1289.2 kcal. The total energy intake of both groups was significantly decreased during the program. The CP group lost 1.9 kg of body weight and 1.9% of body fat and the SP group lost 4.3 kg of body weight and 3.0% of body fat. The body weight was significantly decreased in the SP group compared to the CP group. The triglyceride and total cholesterol, and LDL-cholesterol level of SP group were significantly decreased during the program. However, there were no significant changes in CP group during the program. Also there were no significant changes in lipid profile between two groups. In this study, it is considered that real time communication digital photography method using Kakao Talk application in smart-phone might influence weight control through a trained consumption monitoring. Therefore, smart-phone can lead individuals to rely more heavily on easy-to-monitor visual cues.

• Korean Journal of Optics and Photonics
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• v.19 no.5
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• pp.349-359
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• 2008

For an inner-focusing 3-groups zoom lens system, this study suggests a new initial design method which applies the process that changes thin lenses into thick ones effectively and quickly, using the hybrid lens system(thin lens+thick lens). In other words, the hybrid lens system is the semi-automatic design process that makes the thin lens of one group change into a thick one while the other groups are composed of thin lenses. Keeping the total power of the system fixed, the power of each group and the distance between principal planes can be fixed. Of course, the other groups composed of thin lenses could be changed into thick lenses sequentially by this process. This design conception results in the 1/4" 5 M inner-focusing 3-groups 2x zoom lens system satisfying the specifications and performances of zoom lens for phone cameras. Also aspherization on lens elements of glass and plastic material enhanced the resolution and reduced the lens size. As a result, we have an ultra-compact inner-focusing 3-groups 2x zoom lens system for a phone camera, with a slim size with TTL of 9.8 mm.

• Korean Journal of Optics and Photonics
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• v.32 no.1
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• pp.22-28
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• 2021

We try to extract three-dimensional information, such as the distance from a camera and the actual width and height of an object, from still photographs by a multilens smartphone camera, by means of parallax error. To obtain this information, we develop several formulas and design a method for experimental instrumentation. If the results from this paper were included in algorithms of multilens smartphone cameras, there would be various kinds of applications, such as in the workplace of architectural and civil engineering to obtain an actual dimension, or on a golf course to measure how far away a pin flag is. We expect many more applications of this study, because the multilens smartphone camera is already an important necessity of life.