An erasable magneto-optical disk drive system employing polar Kerr effect readout has been developed within the 3.5 inch half-height form factor (41x101x146mm). The drive exhibits rapid seek times and data transfer rates greater than 1 Mbit/sec. The disk is contained in a cartridge and has a formatted user capacity greater than 50 MBytes. The system is ideal for the personal computer marketplace, giving the performance of a Winchester drive, the portability of a microfloppy and the advantages of optical recording.
{"title":"Magneto-Optic Recording with a Compact Optical Head","authors":"I. Sander, Stephen Slovenkai","doi":"10.1364/ods.1987.fc2","DOIUrl":"https://doi.org/10.1364/ods.1987.fc2","url":null,"abstract":"An erasable magneto-optical disk drive system employing polar Kerr effect readout has been developed within the 3.5 inch half-height form factor (41x101x146mm). The drive exhibits rapid seek times and data transfer rates greater than 1 Mbit/sec. The disk is contained in a cartridge and has a formatted user capacity greater than 50 MBytes. The system is ideal for the personal computer marketplace, giving the performance of a Winchester drive, the portability of a microfloppy and the advantages of optical recording.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121415010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The purpose of this presentation is to explore the test requirements for optical disk media in a production environment. The basic purposes for production testing of media include: process control, media certification and maintenance of quality control standards. Each of these purposes has special test requirements and considerations on the types and methods for data collection and display.
{"title":"Optical Disk Testing Methods Summary","authors":"E. LaBudde, R. Hazel","doi":"10.1364/ods.1984.wcc6","DOIUrl":"https://doi.org/10.1364/ods.1984.wcc6","url":null,"abstract":"The purpose of this presentation is to explore the test requirements for optical disk media in a production environment. The basic purposes for production testing of media include: process control, media certification and maintenance of quality control standards. Each of these purposes has special test requirements and considerations on the types and methods for data collection and display.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"264 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116254759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pregrooved optical disks have the advantage of making the tracking servo easy when writing data and enabling the disk to be exchanged. In pregrooved disks, push-pull tracking servo signals are detected by a change in the intensity distribution of the diffracted beam. Both tracking and focusing servo signal can be obtained by the same photo diode placed in a far field. However, interference between tracking error signals and focusing error signals makes the focusing servo unstable, and the decrease in light intensity due to groove diffraction causes a reduction in signal amplitude. These problems depend not only on the width and the depth but also on the gradient of the edge of a pregroove.
{"title":"Design Consideration of Optical Pregroove Dimensions","authors":"M. Yamamoto, A. Watabe, H. Ukita","doi":"10.1364/ods.1985.thcc2","DOIUrl":"https://doi.org/10.1364/ods.1985.thcc2","url":null,"abstract":"Pregrooved optical disks have the advantage of making the tracking servo easy when writing data and enabling the disk to be exchanged. In pregrooved disks, push-pull tracking servo signals are detected by a change in the intensity distribution of the diffracted beam. Both tracking and focusing servo signal can be obtained by the same photo diode placed in a far field. However, interference between tracking error signals and focusing error signals makes the focusing servo unstable, and the decrease in light intensity due to groove diffraction causes a reduction in signal amplitude. These problems depend not only on the width and the depth but also on the gradient of the edge of a pregroove.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122396242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Fujita, M. Kondo, K. Kime, N. Tomikawa, N. Takeshita
In this paper we report an optical head developed for measuring characteristics of magneto-optical disks. The features of this head are followings:- (1) Collimating system without anamorphic elements. (2) Small phase retardation in signal-readout optical system. (3) Differential readout method using two photodetectors.
{"title":"Optical Head for Magneto-optical Disk Evaluation","authors":"T. Fujita, M. Kondo, K. Kime, N. Tomikawa, N. Takeshita","doi":"10.1364/ods.1985.thaa2","DOIUrl":"https://doi.org/10.1364/ods.1985.thaa2","url":null,"abstract":"In this paper we report an optical head developed for measuring characteristics of magneto-optical disks. The features of this head are followings:-\u0000 (1) Collimating system without anamorphic elements.\u0000 (2) Small phase retardation in signal-readout optical system.\u0000 (3) Differential readout method using two photodetectors.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121531606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tb-Fe amorphous films were found to be very promising materials for magneto-optical recording1), since they have (1) a large perpendicular magnetic anisotropy which ensures a recording density as high as 109 bits/cm2, (2) a Curie point TC of about 140°C which is reasonable from the view points of high thermal stability of written bits and of low laser power for Curie point writing, and (3) a very low medium noise due to the amorphous state. These films, however, have a magneto-optical Kerr rotation θk of only 0.25 degrees at room temperature, which is smaller than that for Gd-Fe and Gd-Co films. Therefore, many efforts have been made in Japan in order to increase θk of Tb-Fe films. Good results are obtained by replacing a part of Tb and/or Fe by Gd and/or Co. The maximum θk found so far is about 0.5 deg for quaternary films with a composition around (Gd0.5Td0.5)0.2(Fe0.7Co0.3)0.8, where θk is measured from the sub-strate (glass) side using light of λ=633 nm wave length.
{"title":"Magneto-Optical Properties of Amorphous Magnetic Thin Films","authors":"S. Uchiyama","doi":"10.1364/ods.1985.waa1","DOIUrl":"https://doi.org/10.1364/ods.1985.waa1","url":null,"abstract":"Tb-Fe amorphous films were found to be very promising materials for magneto-optical recording1), since they have (1) a large perpendicular magnetic anisotropy which ensures a recording density as high as 109 bits/cm2, (2) a Curie point TC of about 140°C which is reasonable from the view points of high thermal stability of written bits and of low laser power for Curie point writing, and (3) a very low medium noise due to the amorphous state. These films, however, have a magneto-optical Kerr rotation θk of only 0.25 degrees at room temperature, which is smaller than that for Gd-Fe and Gd-Co films. Therefore, many efforts have been made in Japan in order to increase θk of Tb-Fe films. Good results are obtained by replacing a part of Tb and/or Fe by Gd and/or Co. The maximum θk found so far is about 0.5 deg for quaternary films with a composition around (Gd0.5Td0.5)0.2(Fe0.7Co0.3)0.8, where θk is measured from the sub-strate (glass) side using light of λ=633 nm wave length.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124663541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masato Yamamoto, K. Mikuriya, M. Sato, M. Hanawaka, A. Ohya
We have developed two test systems for measuring, respectively, the mechanical and optical (recording) characteristics of optical disks. The mechanical characteristics test system measures axial and radial runout, etc. It has optical displacement sensors with accuracy of 0.1 um in the axial direction and 0.01 um in the radial direction. The optical (recording) characteristics test system measures reflectivity, CNR, error rate, defects, etc. The system has a SNR of better than 70 dB.
{"title":"Test System for Measuring Mechanical and Recording Characteristics of Optical Disks","authors":"Masato Yamamoto, K. Mikuriya, M. Sato, M. Hanawaka, A. Ohya","doi":"10.1364/ods.1987.tha5","DOIUrl":"https://doi.org/10.1364/ods.1987.tha5","url":null,"abstract":"We have developed two test systems for measuring, respectively, the mechanical and optical (recording) characteristics of optical disks. The mechanical characteristics test system measures axial and radial runout, etc. It has optical displacement sensors with accuracy of 0.1 um in the axial direction and 0.01 um in the radial direction. The optical (recording) characteristics test system measures reflectivity, CNR, error rate, defects, etc. The system has a SNR of better than 70 dB.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116905071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Markvoort, J. Ramaker, A. Spruijt, J. Verhoeven
The 12" OML DOR disk is a promising medium for permanent non-erasable data storage. It is characterized by: a disk capacity of 109 user bytes per surface, raw initial bit error rate of better than 10−5, sensitivity for hole formation of better than 0.8 nJ for 60 nsec pulses at 8 Hz rotation, and long storage and user life: 5 years for recording and 10 years for reading. These characteristics open a wide range of applications especially for mass storage systems: for which the storage and user life times are very important characteristics.
{"title":"Mechanical, Environmental and Accelerated Ageing Tests on OML Disks","authors":"J. Markvoort, J. Ramaker, A. Spruijt, J. Verhoeven","doi":"10.1364/ods.1984.thcb4","DOIUrl":"https://doi.org/10.1364/ods.1984.thcb4","url":null,"abstract":"The 12\" OML DOR disk is a promising medium for permanent non-erasable data storage. It is characterized by: a disk capacity of 109 user bytes per surface, raw initial bit error rate of better than 10−5, sensitivity for hole formation of better than 0.8 nJ for 60 nsec pulses at 8 Hz rotation, and long storage and user life: 5 years for recording and 10 years for reading. These characteristics open a wide range of applications especially for mass storage systems: for which the storage and user life times are very important characteristics.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127097316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The development of the magneto-optical disk memory has been pursued with extreme rapidity over the last few years. Since initially the CN ratio was low, it was felt that a long lead time would be required to bring the development to the stage of practical application. As will be described below, the characteristics have been constantly improved year after year so that the practical use of the magneto-optica1 disk memory is now only a question of time.
{"title":"Recent Trends of Magneto-optical Disk Memory","authors":"N. Imamura","doi":"10.1364/ods.1985.tubb1","DOIUrl":"https://doi.org/10.1364/ods.1985.tubb1","url":null,"abstract":"The development of the magneto-optical disk memory has been pursued with extreme rapidity over the last few years. Since initially the CN ratio was low, it was felt that a long lead time would be required to bring the development to the stage of practical application. As will be described below, the characteristics have been constantly improved year after year so that the practical use of the magneto-optica1 disk memory is now only a question of time.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129147559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Okada, M. Nakada, K. Toki, H. Gokan, T. Iwanaga, H. Inada
Magneto-optical disk is one of the most promising candidates for erasable optical media.1)2) Considering mass production, optical disks using resin substrates have the advantage of simple pre-groove formation. Among several resins applicable for use in optical disks substrates, Polycarbonate (PC) has superior injection molding characteristics, good humidity resistance and excellent thermal resistance. However, the noise arising from birefringence is the most significant drawback. On the other hand, it is necessary to use excellent protective films since the magneto-optical films are rapidly oxidized in the air. For this reason, various kinds of protective films have been studied for magneto-optical disks.3)4)5) This paper discusses the characteristics of magneto-optical disks using the noise reduced PC substrates and excellent protective films.
{"title":"Magneto-optical Disks Using PC Substrates","authors":"M. Okada, M. Nakada, K. Toki, H. Gokan, T. Iwanaga, H. Inada","doi":"10.1364/ods.1987.thc2","DOIUrl":"https://doi.org/10.1364/ods.1987.thc2","url":null,"abstract":"Magneto-optical disk is one of the most promising candidates for erasable optical media.1)2) Considering mass production, optical disks using resin substrates have the advantage of simple pre-groove formation. Among several resins applicable for use in optical disks substrates, Polycarbonate (PC) has superior injection molding characteristics, good humidity resistance and excellent thermal resistance. However, the noise arising from birefringence is the most significant drawback. On the other hand, it is necessary to use excellent protective films since the magneto-optical films are rapidly oxidized in the air. For this reason, various kinds of protective films have been studied for magneto-optical disks.3)4)5) This paper discusses the characteristics of magneto-optical disks using the noise reduced PC substrates and excellent protective films.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114209338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. N. Gardner, V. W. Hailing, T. Rinehart, A. Funkenbusch, M. A. Khan, D. Siitari, R. Freese
Media product development and media scale-up activities are reviewed. Key aspects of the dynamical and mechanical characteristics of magneto-optic erasable media produced in the 3M scale-up line are discussed. The first generation product at this time is marketplace ready.
{"title":"Status of m/o erasable media production","authors":"R. N. Gardner, V. W. Hailing, T. Rinehart, A. Funkenbusch, M. A. Khan, D. Siitari, R. Freese","doi":"10.1364/ods.1987.thc1","DOIUrl":"https://doi.org/10.1364/ods.1987.thc1","url":null,"abstract":"Media product development and media scale-up activities are reviewed. Key aspects of the dynamical and mechanical characteristics of magneto-optic erasable media produced in the 3M scale-up line are discussed. The first generation product at this time is marketplace ready.","PeriodicalId":268493,"journal":{"name":"Topical Meeting on Optical Data Storage","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127984830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：