Optical Disk Recording Research Articles

Fiber electronic speckle pattern interferometry and its applications in residual stress measurements

A two-dimensional in-plane displacement-sensitive electronic speckle pattern interferometer has been developed. With a fiber coupler with one input and four outputs, two sets of dual-beam interferometric configurations in orthogonal directions are constructed to determine in-plane displacements completely. When a CCD camera with a zoom lens is located at an adequate distance from the specimen, a testing area ranging from 1.4 mm x 1.0 mm to 30.0 mm x 24.0 mm can be examined in quasi-real-time. Incorporated with the hole-drilling technique, it has currently been demonstrated in residual stress measurements. One application is for determining the residual stress of a thick cylinder consisting of two concentric circular tubes with interference fit. The other is for analyzing the residual stress distribution of a recordable optical compact disc. A simple approach to interpreting the values of residual stresses from the displacement contours is presented.

New Recordable Optical Discs with Metal Thin Film and Organic Film on Polycarbonate

A new recordable optical disc which has the advantages of low material cost and wavelength dependence was proposed. It consists of a polycarbonate (PC) substrate, a metal thin film, an organic buffer layer, a metal reflective layer and an overcoat. Its recording mechanism was investigated by atomic force microscopy observation of each layer surface and the recording characteristics were evaluated. It was observed that the recording mechanism involves the thermal deformations of the PC substrate, the thin metal film and the organic buffer layer and the recording characteristics are equal to those of a dye-based CD-R.

PdGeSbTe Alloy for Phase Change Optical Recording

Phase change optical recording disks using a Pd–Ge–Sb–Te quaternary alloy demonstrated high crystallization speed and long-term thermal stability of the amorphous recording marks. This alloy film can be crystallized by a short duration laser pulse of less than 100 ns. It is applicable to a single beam overwrite optical recording system. The crystallized portion of this recording layer on the disk is assigned to single phase and polycrystalline face-centered-cubic (fcc) crystals by transmission electron diffraction. A small amount of Pd atoms (typically 0.2 to 3 at.%) in this alloy improve the thermal stability of amorphous marks.

Application of simulation on the design of phase-change optical recording disks

Optical absorption and thermal conduction are the two key factors affecting temperature distribution and, subsequently, the write, erase characteristics of a phase-change optical recording disk. Therefore, by using carefully measured film physical properties of each layer, this work simulates a transient temperature profile while simultaneously considering optical absorption and thermal conduction. Through the simulated transient temperature profile, cooling-rate and reflectivity, dependence of phase-changed spot size on the laser power and laser pulse duration was observed. The proper combination of the disk structure and the associated write, erase conditions are obtained as well. A disk structure can subsequently be designed on the basis of this information. In addition, a novel dielectric layer, i.e. hydrogenated amorphous carbon (/spl alpha/-C:II), is simulated and compared with the disk applying conventionally used ZnS-SiO/sub 2/ dielectric layers. The disk structures used herein are PC/ZnS-SiO/sub 2//GeSbTe/ZnS-SiO/sub 2//Al and PC//spl alpha/-C:H/GeSbTe//spl alpha/-C:H/Al. According to those results, /spl alpha/-C:H film is highly promising as a dielectric layer of the phase change optical recording disk for both wavelengths of 780 and 660 nm.

Chapter 11 Micromanipulation of Chromosomes and Spindles in Insect Spermatocytes

Micromanipulation is a useful technique for exploring various aspects of cell division, including spindle assembly, the interaction of chromosomes with the spindle, cell cycle regulation, and cytokinesis. Micromanipulation of chromosomes and spindle components has been done primarily in spermatocytes of insects, such as praying mantis, crickets, crane flies, Drosophila , and especially grasshoppers. This chapter focuses on the various methods used to manipulate insect spermatocytes along with some examples of possibilities with a needle in a cell. The chapter provides step-by-step descriptions of performing micromanipulation using a video/computer-enhanced polarization microscope in which chromosomes, centrosomes, and microtubules are readily observed. Micromanipulation is usually carried out in intact living cells visualized by video microscopy and chromosome micromanipulation is done primarily with phase contrast microscopes. Polarization microscopy is used to visualize centrosomes and microtubules for micromanipulation, which is inspired by Shinya Inoué's designs. The images are stored either on an optical disk recorder or on a computer hard disk for further image processing, particularly contrast enhancement and haze removal by unsharp masking.

9-4 光ディスクレコーダにおける各種PRMLのシミュレーション比較

9-4 光ディスクレコーダにおける各種PRMLのシミュレーション比較

A steady-state heat conduction solution for optical disk recording using constant or periodically modulated laser irradiation

A fast method is presented for accurately calculating just the steady-state temperature in thin-film multilayers heated by continual laser irradiation. The key features are a simple coordinate transformation and a special lattice with which the steady-state portion of the heat conduction solution reported earlier [J. Appl. Phys. 75, 4382 (1994)] may be quickly and efficiently extracted. The earlier solution, expressed in terms of Fourier-transformed Green’s functions, was designed for temperature problems as typically found in optical disk recording situations. In particular, the laser irradiation was assumed to be modulated arbitrarily in time and finite in duration. As the pulse length increases, though, both execution time and memory requirements increase. Thus when long laser pulses are used to model continual laser irradiation, the numerical performance may degrade to unacceptable levels. For the case of periodically modulated laser irradiation (including constant laser irradiation as a special case) which is important for magneto-optical disk recording, the time and memory requirements can be reduced substantially by defining a new coordinate and lattice system in the space spanned by the time and scan directions. In frequency space, the new lattice filters out the frequencies which contribute to the transient part of the solution and retains only the frequencies which contribute to the steady-state part. The temperature formulas themselves remain unchanged; they are merely evaluated over a specially defined lattice which yields just the steady-state temperature more quickly. This paper describes the new coordinate and lattice systems, discusses some numerical issues, and compares the results of the steady-state theory to the results of the earlier original theory which includes the transients.

Improving Prairie Pond Counts with Aerial Video and Global Positioning Systems

Technological advances in tools available for habitat surveys have occurred since the inception of the Aerial Waterfowl Breeding Ground Population and Habitat Surveys in North America (BGS). We developed a method using aerial video, a global positioning system (GPS), and an optical disk recorder to assess pond numbers in the Prairie Pothole Region. We analyzed low altitude near infrared video for 12 air-ground segments and 30 29-km transect segments that are part of the annual BGS in southern Saskatchewan. Video interpretation was done with a combination of manual and automated procedures. Average omission and commission errors for the 12 air-ground segments were 0.21 and 0.22, respectively. Estimating omission and commission errors was confounded by changes in the presence and level of water between dates of video and ground BGS. Use of GPS automated the organization of the video by transect segment on the optical disk recorder, thus reducing labor required to process video images. The time required to interpret the number of ponds for a 0.2- x 29-km transect segment ranged from 9 to 59 minutes and varied with pond abundance, size, and contrast with background. The system enabled a rapid and accurate assessment of the average number of ponds. Video imagery can be used to estimate other habitat attributes (e.g., pond area) and is a valuable source of data for analysis of habitat trends.

The CD-ROM and optical disc recording systems

1. Introduction to optical recording 2. Basic optics 3. Lasers 4. Photodetectors 5. Media substrates 6. Mastering 7. Making the CD-ROM book 8. Magneto-optic thin film production 9. WORM media 10. Magneto-optic media 11. Magneto-optical drive systems 12. Noise in magneto-optic drive systems 13. Magneto-optical recording applications 14. Phase change media 15. The future for optical discs Glossary Index

Multilevel run-length-limited modulation codes for optical disk recording system

A generalization of the run-length-limited (RLL) code has been studied for multilevel recording systems where more than one kind of mark is used to record information. The run-length constraints have been generalized to include the spacing in addition to the minimum and maximum run-length constraints. The ratic of the minimum run length to the detection window has become arbitrarily adjustable. This provides the flexibility to design the modulation codes which match with the resolution and jitter characteristics of the recording system. The method of the calculus of variations has been applied to the asymptotic behavior of the amount of information stored in a sufficiently long code sequence. The formulation has been obtained for the code characteristics, which include the maximum density ratio, the maximum amount of information contained in the detection window, the average rate of appearance for individual run lengths, etc. The effect of the multilevel recording scheme depends on the number of the levels, the minimum and maximum run length, and the spacing. The optimum selection of these parameters can realize a large recording capacity close to the intrinsic potential of the multilevel recording system.

Three-dimensional reconstructions of the primary palate region in normal human embryos.

Our knowledge of the precise spatial relationships of human primary palate morphogenesis remains poorly defined. This is due to intrinsic difficulties that exist in the study of the subject matter and a lack of adequate methodologies. We present a novel new method to allow precise three-dimensional (3-D) visualization of developing embryonic structures in previously sectioned embryos. In our study we focus on human primary palate development. Five normal human embryos from the Carnegie collection were used. 3-D reconstructions appear similar to scanning electron micrographs (SEM); however, unlike in SEM studies, the original specimen has been previously sectioned histologically. 3-D reconstruction from serial sections involved 1) histological preparation of specimen, 2) projection onto digitizing board, 3) digitization, 4) automated reassembly, and 5) relay to interactive optical disc recorder. Detailed observations of each reconstruction were then made. Data generated in this manner may also be used in the near future for quantitative morphometrics. Thus, 3-D reconstruction techniques presented in this paper generated precise spatial information on the development of the human primary palate.

Sequences and a new code with spectral nulls at rational submultiples of the symbol frequency

Auxiliary pilot tone insertion, used for positioning the servo of magnetic or optical disk recorders, requires codes that give rise to a spectral null at an arbitrary frequency. Sequences with asymetrical runlength constraints containing spectral nulls at rational submultiples of the symbol frequency are investigated. A sufficient condition for spectral nulls at rational submultiples of the symbol frequency is given in terms of a simple runlength requirement. A new code with rate=1/3 is presented with spectral nulls at the normalized symbol frequencies 1/4, 1/2, and 3/4.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

他船実画像からの航行情報抽出方法についての研究-III : 画像処理専用機と特定線分抽出アルゴリズムを利用した高速化

We have focused on image processing and understanding techniques for mechanization of ship operator's eyesight, and studied extraction of navigation information, especially the distance between a target and own ship, from an image of the target at sea. In this paper, we describe Nexus Ranging System (NRS for short) which is speeding up ranging system using specially designed image processing machine "nexus-6800" and algorithm. NRS consists of nexus-6800, engineering work stations, an optical disk recorder and a video camera as the hardware. Images are fed into nexus-6800 by the video camera through the optical disk recorder. NRS processes the input image for binarization at first and edge detection. After putting away its noise, NRS extracts a horizon and waterline without a thinning process. Then, the coordinates (x, y) of the horizon and waterline are used for computing the distance by the ranging equations which have been reported in a series of the studies. NRS has processed 214 image and computed the distances. It is possible for NRS to measure the distances with the error rate less than 11 percent of radar distances. The accuracy is fine-grained enough for practical use.

Time lapse video recordings of highly purified human hematopoietic progenitor cells in culture.

Major hurdles in studies of stem cell biology include the low frequency and heterogeneity of human hematopoietic precursor cells in bone marrow and the difficulty of directly studying the effect of various culture conditions and growth factors on such cells. We have adapted the cell analyzer imaging system for monitoring and recording the morphology of limited numbers of cells under various culture conditions. Hematopoietic progenitor cells with a CD34+ CD45RAlo CD71lo phenotype were purified from previously frozen organ donor bone marrow by fluorescence activated cell sorting. Cultures of such cells were analyzed with the imaging system composed of an inverted microscope contained in an incubator, a video camera, an optical memory disk recorder and a computer-controlled motorized microscope XYZ precision stage. Fully computer-controlled video images at defined XYZ positions were captured at selected time intervals and recorded at a predetermined sequence on an optical memory disk. In this study, the cell analyzer system was used to obtain descriptions and measurements of hematopoietic cell behavior, like cell motility, cell interactions, cell shape, cell division, cell cycle time and cell size changes under different culture conditions.

特集 ディジタル記録技術とその応用 画像記録機器の動向 画像記録用光ディスク

特集 ディジタル記録技術とその応用 画像記録機器の動向 画像記録用光ディスク

光ディスク技術への期待

光ディスク技術への期待

Near-field optical disk recording for very high data density

The use of subwavelength near-field apertures opens the possibility of optical dish data density increases in excess of 4 orders of magnitude.

Imaging intracellular membrane traffic and organelle dynamics using confocal microscopy

Movements of exocytic and endocytic vesicles within cells are controlled in part by active transport along microtubules. The forces generated by microtubule-based transport are also known to strongly influence the distribution and shapes of membranous organelles, such as mitochondria and the endoplasmic reticulum. The ability to observe such dynamic interactions between cytoskeletal elements and fluorescently-labelled intracellular membranes in living cells has been improved recently by the advent of scanning laser confocal microscopy. Here we describe the use of this technique to study activities of the Golgi apparatus in living cells.Vesicular traffic, diffusive transport and morphological dynamics within the Golgi apparatus of cultured rat hippocampal astrocytes were imaged with a Bio-Rad MRC-500 scanning laser confocal microscope. Golgi elements were labelled with NBD-ceramide, a molecule which serves as a vital stain for the trans-most cisternae of Golgi stacks. Single scans of the specimen, obtained with the laser microscope's slow scan rate (4 sec/image), were stored sequentially on an optical memory disk recorder.

INTERACTIVE VIDEO FOR LEARNING LANDSCAPE TREES

Repetitive exposure to plant morphology and characteristics is necessary for students to learn to identify woody landscape plants. We developed a computer operated video program which will supplement what students learn in outdoor labs and in lecture. The interactive video tutorial allows the computer integration of script with control of a large collection of video images that come from 35 mm slides, video images, photographs, drawings and actual plant specimens. We have tried the less expensive still video floppy technology (Kodak SV7500 Still Video Multidisk Recorder) and the Write-Once laser disc technology (Panasonic TQ-3031F Optical Disc Recorder). Both systems have advantages, but the latter offers more options at a much higher cost. Motivation for use of the program comes from self tests and the possibility to review visual examples.

NeuroVideo: a program for capturing and processing time-lapse video

We have developed a program for the Macintosh computer to control a Panasonic Optical Memory Disk Recorder (OMDR) in order to generate time-lapse video recordings of growing neurons. The software, in addition to regulating the timing of a recording in a flexible way, can also digitize and pre-process images before writing them out to the optical disk. NeuroVideo includes a complete set of functions to enhance images, and provides both an easy-to-use graphical interface and a simple but powerful text-based scripting language.