• Title, Summary, Keyword: Recording

Search Result 3,024, Processing Time 0.05 seconds

Development of 3-Dimensional Polyimide-based Neural Probe with Improved Mechanical Stiffness and Double-side Recording Sites (증가된 기계적 강도 및 양방향 신호 검출이 가능한 3차원 폴리이미드 기반 뉴럴 프로브 개발)

  • Kim, Tae-Hyun;Lee, Kee-Keun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.11
    • /
    • pp.1998-2003
    • /
    • 2007
  • A flexible but implantable polyimide-based neural implant was fabricated for reliable and stable long-term monitoring of neural activities from brain. The developed neural implant provides 3-dimensional (3D) $3{\times}3$ structure, avoids any hand handling, and makes the insertion more efficient and reliable. Any film curvature caused by residual stress was not observed in the electrode. The 3D flexible polyimide electrode penetrated a dense gel whose stiffness is close to live brain tissue, because a ${\sim}1{\mu}m$ thick nickel was electroplated along the edge of the shank in order to improve the stiffness. The recording sites were positioned at both side of the shank to increase the probability of recording neural signals from a target volume of tissue. Impedance remained stable over 72 hours because of extremely low moisture uptake in the polyimide dielectric layers. At electrical recording test in vitro, the fabricated electrode showed excellent recording performance, suggesting that this electrode has the potential for great recording from neuron firing and long-term implant performance.

Recording and Retrieving of Angular Multiplexed Near-field Holograms (근접장 홀로그램의 각도 다중화 저장 및 재생)

  • 김경염;이병호
    • Proceedings of the Optical Society of Korea Conference
    • /
    • /
    • pp.60-61
    • /
    • 2001
  • We present our experimental results on the recording and retrieving of multiplexed near-field holograms using near-field scanning optical microscopy (NSOM) and a conventional rectangular-parallelepiped or cubic photorefractive crystal. Experimental results show that we can get the angular selectivity comparable with that of the volume hologram and the retrieved spot size was smaller than the Rayleigh's limit. The results also show that the angular selectivity and the retrieved spot size are strongly dependent on the recording distance between the object and the recording medium.

  • PDF

Optical characteristics of discs for near-filed recording (근접장 기록을 위한 디스크의 광학적 특성)

  • Min, Cheol-Ki;Park, No-Cheol;Park, Kyoung-Su;Park, Young-Pil
    • Transactions of the Society of Information Storage Systems
    • /
    • v.5 no.2
    • /
    • pp.64-69
    • /
    • 2009
  • In this paper, we investigate field distribution and interference pattern in the exit pupil and in the focal region. Also, we compare with metal and dielectric substrate for near-field recording. To obtain field distribution, we use modified vector diffraction theory and Zernike Polynomials. Finally, we design and optimize refractive index and thickness of disk for near-field surface recording and cover-layer incident recording.

  • PDF

Design and Evaluation of An Electromagnetic Driven Actuator for Near-field Optical Recording System (근접장 광기록 시스템용 전자기구동 액추에이터의 설계 및 평가)

  • 김석중;이용훈;이철우;서중언
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.24 no.11
    • /
    • pp.2732-2741
    • /
    • 2000
  • Combination of magnetic recording technology and optical recording technology such as Near Field Optical Recording is watched recently. In order to accomplish this technology, the development of an electromagnetic driven mm-sized mirror shifting laser beam in track direction have to needed. In Near Field Optical Recording System, shifting laser beam in track direction mean as fine tracking and means as coarse tracking. Therefore in Near Field Optical Recording, 2-stage actuator is composed of servo controller in reading or recording information on disc layer. In our research, through design and simulation process of driven mm-sized mirror, we arrange systematically design process of driven mm-sized mirror having good frequency transfer characteristics. Design and simulation processes included modal analysis of spring, calculation of magnetic moment according to the number of turns and geometric configuration of coil and magnetic circuit analysis meaning that calculation of magnetic flux density in air gap of magnetic circuit. After that we design and make parts of driven mm-sized mirror, assemble and evaluate our electriomagnetic driven mm-sized mirror. we compared design values with actual characteristic values and present solution scheme. Through these processes we performed manufacturing of an electromagnetic driven mm-sized mirror having good frequency-domain characteristics and high sensitivity characteristics.

An Electromyographic Study on Mandibular Rest Position Induced by Several Methods (하악안정위 유도에 관한 근전도학적 연구)

  • Chang Jung;Kyung-Soo Han;Min Shin
    • Journal of Oral Medicine and Pain
    • /
    • v.18 no.2
    • /
    • pp.121-130
    • /
    • 1993
  • Mandibular rest position is very essential position because in that position, masticatory muscularture can be reciprocally coordinative and unstrained. So obtaining a good ability to establish and maintain rest position in non-functioning state is mandatory for treatment of patient with craniomandibular disorders. In general, many types of mandibulr movement exercise start from rest position and use the sense of muscle relearning, that is, muscle smoothness and relaxation, throughout the exercise period. In this study, 44 normal subjects for control group and 37 patients with craniomandibular disorders for experimental group participated and they were classified into 3 subgroups, respectively. One method to guide mandibular rest position was used for one subgroup, so theree methods were used for this study, 1)self-guided rest position without any education, 2) guided by Rocabado's tongue rest position, 3) guided through swallowing after Dawson's centric relation. To record electromyographic activity, Bioelectric processor EM2 (Myotronics, U.S.A.) was used. The numbers of sessions from start to stable resting electromyographic level and muscle activities in stable state were recorded and two recordings which were first and second, 3 days after first recording, were done, The data were processed with SPSS/PC+package. The obtained results were as follows : 1. Mean number of sessions in second recording were fewer than those in first recording in both groups. In comparison among 3 subgroups, mean number of sessions of subgroup guided through Dawson's method were fewer than those of other groups though it is not statistically significant. 2. There was a difference of mean number of sessions between control and experimental group in first recording, but in second recording there was no difference in any cases. 3. Mean value of muscle activity were generally not different without regard to group and method if once come to stable resting position level. Mean value of muscle activity of guided subgroups showed a tendency of decreasing in second recording than in first recording. However, in self-guided subgroup there was a inconsistent pattern. 4. The amounts of change in session number from first to second recording in control group were fewer than those in experimental group.

  • PDF

Eutectic-based Phase-change Recording Materials for 1-2X and 4X Speed Blu-ray Disc

  • Seo Hun;Lee Seung-Yoon;Lee Kwang- Lyul;Kim Jin-Hong;Bae Byeong-Soo
    • Transactions of the Society of Information Storage Systems
    • /
    • v.1 no.1
    • /
    • pp.34-41
    • /
    • 2005
  • We report some recent results in the rewritable Blu-ray Disc with enhanced overwrite cyclability by using the growth dominant eutectic based Ge(Sb70Te30)+Sb recording layer, GeN interface layer and write strategy optimization. We have developed phase-change optical media with appropriate write strategy for 36(i.e., 1X)-72Mbps(i.e., 2X) dual speed Blu-ray Disc system and fur the future high speed optical data storage. For recording layer, eutectic-based Ge(Sb70Te30)+Sb material was used and Sb/Te ratio and Ge content were optimized to obtain proper erasability and archival stability of recorded amorphous marks. The recording layer is wrapped up in GeN interface layers to obtain overwrite cyclability and higher crystallization speed. In addition, we designed appropriate write strategy so called Time-Shifted Multipulse (TSMP) write strategy where starting position of multipulse parts are shined from reference clock. With this write strategy, the jitter characteristics of the disc was improved and we found that leading edge jitter was improved much more than trailing edge jitter in 1X-2X speed recording. Finally, we investigated the higher speed feasibility of 144Mbps(i.e., 4X) by adopting some elemental doping to the eutectic based Ag-In-Sb-Te recording layer and structural optimization of constitution layers in Blu-ray Disc. In the paper, we report the effect of Sn addition for the feasibility of higher speed recording. The addition of Sn shows increases of the crystallization speed of phase change recording layer.

  • PDF

Polarization recording and reconstruction in the chalcogenide As-Ge-Se-S thin films (비정길 칼코게나이드 As-Ge-Se-S 박막에서 편광기록 재생)

  • 장선주;박종화;손철호;정홍배
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.9
    • /
    • pp.781-785
    • /
    • 2000
  • Chalcogenide glasses are suggested as a candidate for optical recording. In this study, we have investigated the holography recording and reconstruction of the polarization state in chalcogenide As$_{40}$ Ge$_{10}$Se$_{15}$ S$_{35}$ thin films. We have used a He-Ne laser light(633nm) to probe and record of the grating. Also the polarization state of object beam was modulated with a λ/4 wave plate. The polarization state of the +1st order diffracted beam was generated by readout of the grating with a linearly polarized reference beam. It was the same-handed polarization state as the polarization state of the recording beam. The result is shown that the diffraction efficiency of circularly polarized recording represents higher than other polarization state.ate.e.

  • PDF

A Computational Method to Consider the Saturation of Magnetic Field In a High Density Recording Head

  • Park, Gwan-Soo
    • Journal of Magnetics
    • /
    • v.8 no.4
    • /
    • pp.164-168
    • /
    • 2003
  • In high density recording system, the recording head field on a medium should be focused in small bit area and should have a sufficient value to overcome the medium coercivity, which resulted in head saturation. In this paper, an efficient method to access the head field and field gradient considering head saturation is presented. The magnetic vector potential on the head surface is pre-calculated considering head saturation in several cases and accumulated into database. The head field on the recording media is easily produced solving Laplace equation using accessed magnetic vector potential boundaries. The computed head field is compared with a quantified magnetic force microscopy measurement.

Heat Transfer Analysis on Phase Change Optical Disc with Land/Groove Recording (랜드/그루부 기록형 상변화 광디스크 박막에 대한 열전달 해석)

  • Lee, J.D.;Hong, S.K.;Cho, H.H.
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.1621-1626
    • /
    • 2003
  • This study deals with the heat transfer analysis on phase change optical disc with land/groove recording by means of numerical method. Finite difference time domain(FDTD) method was used to obtain the amount of absorption of light propagating inside disc and finite difference element(FEM) method was used to calculate the temperature distribution. The calculated results present the detailed information of recording characteristics on the phase change optical disc. The temperature profiles are quite different between the land track and the groove track. The recorded mark shape on land track is smaller and more elliptic than that on groove track. It is shown that the thermal problem to the neighboring track takes place due to secondary peaks. It is found that the different write strategy should be applied to land and groove recording, respectively.

  • PDF

Simple Near-Field Optical Recording Using Bent Cantilever Probes

  • Kim, Jeong-Yong;Song, Ki-Bong;Park, Kang-Ho;Lee, Hyo-Won;Kim, Eun-Kyoung
    • ETRI Journal
    • /
    • v.24 no.3
    • /
    • pp.205-210
    • /
    • 2002
  • This paper describes our high-density near-field optical recording using bent cantilever fiber probes installed in an atomic force microscope. We conducted a near-field reading of nano-scale hole patterns with a 100 nm spatial resolution and a 25 ${\mu}m$/s scan speed; this implies a capability of a data reading density of 60 Gb/$in^2$ with a 0.25 kbps data transfer rate. In addition, we investigated re-writable near-field recording on photochromic diarylethene films. We successfully recorded erasable memory bits having a minimum width of 600 nm in a writing time as short as 30ms. We found that using a cantilever probe simplifies the setup and operation of the near-field optical recording system and may offer multifunctional recording capabilities.

  • PDF