In this paper, a design method based on genetic algorithm is proposed. Proposed design method is useful for inexperienced engineers to select a concept design and it also offers optimized result. A voice-coil actuator for optical image stabilization system in mobile phone camera is designed by using this method. To reduce the size, the optical image stabilization system is integrated with auto-focusing module and the Hall Effect sensor shares a magnet with a voice-coil. Combined electromagnetic analysis is used to reduce computing time. The final design from genetic algorithm is fabricated and verified experimentally. Experiment result shows that combined electromagnetic analysis is reliable and the final design has good performance.

In this paper, 2-axis voice coil actuator of optical image stabilization which is a technique to compensate a trembling of camera caused by a vibration of user's hand is suggested. The actuator is designed for mobile phone camera. Considering total size and application of auto focusing module, the concept of the moving auto-focusing module is selected for optical image stabilization. The handshake of mobile phone is measured to define the specification of the actuator. Two kinds of 2-axis mechanisms made of two prismatic joints are designed and united the electromagnetic part which is already designed. Finally, two types are fabricated and verified experimentally.

Abstract In this paper we suggested the moving magnet type actuator for optical disc drive which has high frequency of flexible mode. Generally, moving magnet type actuator has the advantage for increase the frequency of flexible mode. But it has low driving sensitivity due to the weight of its moving part. To overcome this shortcoming, we designed the model with the closed electromagnetic circuit for tracking direction. In addition, we improved the driving sensitivity and frequency of flexible mode by using of DOE (design of experiment) procedure for EM circuit. Consequently, it is verified that final designed model satisfied with the desired specifications Key Words : Moving Magnet type Pickup Actuator, High Flexible Mode frequency, Electromagnetic circuit, Design of Experiments 1. 서 론 광 정보저장기기는 첫째 세대인 CD가 디지털 음악의 기록 및 재생을 위한 미디어로 최초 등장한 이후 하드디스크와 함께 개인 컴퓨터의 중요한 정보저장기기로써 발전해 왔다. 이후 90년대 중반에 나온 DVD는 동영상의 기록 및 재생을 위한 미디어로써 그 용도를 확대하였다.[4] 현재는 HDTV 고화질 방송과 영화 등 대용량의 정보저장기기의 수요가 증가함에 따라 빠른 데이터 전송률과 높은 저장용량을 갖는 광 정보저장기기가 요구되고 있다. 이러한 추세에 따라서 광 저장기기는 고밀도화와 고배속화를 이루어 왔으며, 이를 위해 서보 시스템의 요구 성능도 보다 높아졌다. 광학디스크드라이브 서보의 대역폭은 엑츄에이터의 유연모드에 의해 제한되며 따라서 서보의 대역폭을 높이기 위해 높은 유연모드 주파수를 갖는 엑츄에이터의 개발이 필요하게 되었다.[1,2,3] 본 논문에서는 높은 유연모드 주파수를 갖는 가동 자석형 엑츄에이터를 제안하였다. 일반적으로 가동 자석형 엑츄에이터는 높은 유연모드 주파수의 구현이 가능한 장점을 가지고 있는 반면 가동부에 장착돼 있는 자석의 무게로 인해 감도가 떨어지는 단점을 가지고 있다. 이러한 단점을 보안하기 위해 코일을 가동자석 사이에 배치하여 폐전자기회로와 유사한 효과를 얻는 자기회로를 제안하였다. 제안된 모델의 동특성을 전자기 해석과 구조해석을 통해 도출하고, 자기부의 최적화 과정을 통해 모델의 성능을 향상시켰다. 마지막으로 제작된 최종모델의 성능을 실험하였고, 앞서 전자기해석 및 구조해석의 결과로 예측한 최종모델의 성능과 일치함을 확인하였다.

Five different types of 2D–π–A (vinylcyanoacetate)pyran derivatives, each having two donor (2D) and one acceptor (A) groups showed significantly large Stokes shifts. Their fluorescence bands shifted to longer wavelengths with an increase in solvent dielectric constant. The π-conjugated moiety, such as a carbazolyl group, as an electron donor did not impart red-emission saturation. A locked ring structure of the electron donor group led to narrowing of the full width at half maximum (fwhm) and to increased dipole moment in the ground state; in addition, bulky donor groups resulted in molecular stability and restrained electronic perturbation on the excited state. An EL device based on the dyes displayed bright and saturated red light with a high luminance of about 2000cd/m2 at a current density of 160mA/cm2 at 16V.

FET type sensor(Ca-ISFET) was fabricated by micropool and photolithographic method utilizing photosensitive polymer as membrane materials. When OMR-83 negative photoresist was used as membrane material, it gave good sensitivity by micropool method with dioctyladipate as plasticizer but it could not be used in the photolithographic method. When poly(viny1 butyral), PVB was used as membrane material, it gave relatively high sensitivity () for concentration range of by photolithographic method. PVB also provided good adhesion to the pH-ISFET base device without adhesion promoter pretreatment and any plasticizer.

An FET-type K+-sensitive sensor with a membrane composed of a hydrophobic inner layer and a hydrophilic outer layer has been fabricated by a photolithographic process. The base chip for the sensor is a pH-ISFET with a thin Si3N4 layer. Negative photoresist (OMR-83) is used as the inner layer and poly (vinyl pyrrolidinone-co-vinyl acetate) solution in tetrahydrofuran containing valinomycin and 2,6-bis-(p-azidobenzylidene) cyclohexanone photosensitizer is used as the outer sensing membrane material. The K-ISFET sensor with double-layered membrane shows a high sensitivity (56 mV/decade) toward K+ ion, rapid response (1–2 s) and low interference (less than 3 mV/decade) from the competing H+ ion.