KR20000037810A - Cartridge for recording/reproducing near field having many discs - Google Patents

Abstract

PURPOSE: A cartridge for recording/reproducing a near field having many discs is provided to improve a recording capacity and a reproducing speed. CONSTITUTION: A tip for accessing a higher disc(10) has a conical form by processing. In recording, the tip forms a micro recording mark by rising in a micro rising height from a disc(1) with a first slider(18) and condensing a light projected by passing an optical fiber(16) in a recording film of the higher disc(1) in an optical shape of near field. In reproducing, the tip receives a reflective light reflected from the recording film and retrogressed an optical path by radiating the light of a reproducing level in the recording film of the disc(1). The received reflective light is totally reflected to an outer optical detector by a total reflective mirror(14) by retrogressing the optical path and passing the optical fiber(16) and an optical coupler(15). Then the outer optical detector converts the reflective light to an electric signal.

Description

Cartridge for Near Field Recording / Reproduce With Plural Discs

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cartridge for protecting a recording medium from external pollutants and impact sources. In particular, the present invention relates to a near field recording / reproducing apparatus having a plurality of disks to increase the recording capacity and reproduction speed by accessing a plurality of disks by a near field. Relates to a cartridge.

The information recording medium is an optical recording / reproducing method of phase change type recording medium. A DVD-RAM in which data is recorded up to 4.7 GB on a 120 mm diameter disk has been developed and spread. In addition, ASMO (Advanced Storage Magneto Optical) having a recording capacity of 6.1 GB has been developed as a magneto-optical recording medium. Although the information recording medium has been actively researched for high density in response to a large amount of information such as moving images, the recording capacity is satisfactory in the face of optical and physical limitations caused by the conventional optical recording method or magneto-optical recording method. The level is not reached. For example, a 120-mm diameter single-sided 2.6-GB DVD-RAM, which is currently in practical use, cannot accommodate an image of a resolution corresponding to high-definition television (HD TV) for more than two hours. In addition, the disc drive device for recording / reproducing the recording medium of the optical recording / reproducing method or the magneto-optical recording / reproducing method has increased vibration and noise as the high speed increases, making it difficult to control the servo, thereby increasing the speed beyond a certain limit. There is no problem.

In the conventional optical recording / reproducing method, in order to increase the recording capacity, the pit (or recording mark) size must be small and the track width must be narrow. However, there is a limit in improving the recording density since the light spots focused on the recording medium cannot be smaller than the so-called "diffraction limit" in order to form a pit, which is a minimum information unit cell, in the recording film of the recording medium. . That is, the size of the light spot is limited to be smaller than the diffraction limit proportional to λ / NA depending on the wavelength λ of the light source and the numerical aperture NA of the objective lens. In order to make the size of the light spot smaller than the diffraction limit value, the wavelength λ must be shortened or the numerical aperture NA must be increased. Recently, a blue laser with a wavelength of 450 nm has been developed for commercialization, but there is a limit to accepting high density information because the light spot cannot be small within the wavelength of light.

In light of the trend of mass storage of information, a new recording / reproducing method is required to overcome the limitations of the current optical recording / reproducing method. Recently, attention has been focused on the Near Field Recording / Reproduction (NFR) method using Near Field, which is expected to significantly improve recording capacity based on the development of microscope technology. .

Near field recording / reproducing method enables recording / reproducing of hundreds of angstroms of information cells using near field optics technology and ultra-micro electro mechanical system (MEMS) technology. Can be increased beyond the conventional optical recording / reproducing method. For example, the near field recording / reproducing method can record / play more than 20 Gbytes of data that can record HDTV-class video data over two hours in MPEG2 quality on one side of a 3 cm diameter disk, so that the information recording medium has a large capacity. It can be miniaturized. The near field recording / reproducing data recording / reproducing apparatus comprises an optical tip of a nano scale and a system capable of driving the optical tip with high precision. The optical tip maintains a focal length within several tens of nm from the recording medium to focus light onto the recording medium so that light spots focused on the recording medium are focused to a small size. As a result, since light spots are condensed minutely on the recording medium of the near field recording / reproducing method, a pit formed on the recording medium is formed to have a small size so that a large amount of information can be recorded. At the time of reproduction, since the light intensity reflected from the recording medium decreases exponentially as it is far from the surface of the recording medium, the optical tip receives the reflected light by maintaining the focal length within several tens of nm from the recording medium, as in the case of recording. By photoelectric conversion, information is reproduced.

However, in the near field recording / reproducing method, the recording capacity is limited by the magnetic domain size or grain size of several nm to tens of nm cannot be made smaller. In addition, the near field recording / reproducing method has a problem that it is difficult to increase the reproduction speed due to the small intensity of light detected due to the small domain size.

In addition, the near field recording / reproducing method maintains a small focal length between the optical tip and the recording medium as described above, and transmits light to the head driving means and the optical tip for driving the optical tip to randomly access the recording medium. There is a need for optical transmission means.

It is therefore an object of the present invention to provide a near field recording / reproducing cartridge having a plurality of discs to increase the recording capacity and reproduction speed.

1 is a perspective view showing a near field recording / reproducing cartridge having a plurality of disks according to an embodiment of the present invention.

FIG. 2 is a perspective view of the disk shown in FIG. 1 from another angle. FIG.

3 is a perspective view showing the head shown in FIG.

4 is a longitudinal cross-sectional view of the portion “A” in FIG. 3.

5 is a longitudinal sectional view of the portion “B” in FIG. 4.

<Description of the code | symbol about the principal part of drawing>

1: disc 2: frame

4: cover 8: flange

10: suspension base 11,31: suspension

12: VCM magnet 14: total reflection mirror

15,35: optocoupler 16,36: optical fiber

16a: Tip 18,38: slider

18a: Hole 20: permanent magnet

30: light incidence / exit guide hole 34: light wavelength selective mirror

100: head

In order to achieve the above object, a near field recording / reproducing cartridge having a plurality of disks according to the present invention comprises at least two or more recording media, incident light incident on the respective recording media and reflected light reflected from the respective recording media. At least two light converging means for converging the light transmitted through the optical transmission path to the recording medium and for guiding the light reflected from the recording medium to the optical transmission means; And an elevation height control means for causing the means to float within a small distance from the recording medium, a conveying means for transferring the elevation height control means to an arbitrary position on the recording medium, and a recording medium driving means for rotating the recording media.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 1 to 5.

1 is a perspective view showing a near field recording / reproducing cartridge having a plurality of disks according to an embodiment of the present invention, and is a perspective view partially cut away to show an internal configuration.

In the configuration of Fig. 1, the near field recording / reproducing cartridge having a plurality of disks according to the present invention shields the frame 2 and the cartridge frame 2 on which two disks 1 and the head portion 100 are installed. A cover 4 is provided. The frame 2 and the cover 4 prevent the disk 1 and the head 100 from being contaminated with dust or foreign matters from the outside and prevent the physical damage to the disk 1 from occurring. 1) and the head part 100 will be protected. The two discs 1 and the head part 100 are shielded by an airtight structure by the frame 2 and the cover 4 and are disconnected from the outside.

In the two discs 1, flanges 8, which serve as the center of rotation of the disc 1, are compressed in the center hole portion as shown in FIG. In addition, a permanent magnet 20 is attached to the flange 8. The flange 8 and the disk 1 are rotated by the rotational force generated from the permanent magnet 20. The flange 8 clamps the disk 1 toward the center of rotation so that the disk 1 does not flow in the vertical direction when the disk rotates. Permanent magnet 20 is attached to the flange 8 serves to generate a rotational driving force of the disk (1). To this end, a coil (not shown) to which a current is applied is provided in the disc driver to face the permanent magnet 20. When a current is applied to the coil, an electromagnetic circuit is formed between the permanent magnet 20 and the coil to generate a rotation force, and the rotation direction is determined according to the direction of the current. Here, the permanent magnet 20 and the flange 8 correspond to the rotor portion of the motor, and the coils and coils (not shown) coils installed in the disc drive device correspond to the stator portion of the motor.

3 is a perspective view of the head part 100 for showing the head part 100 shown in FIG. 1 in detail. 4 and 5 respectively show longitudinal cross-sectional views of part “A” and part “B” in FIG. 3.

3 to 5, the head part 100 includes a suspension base 10 having a light incidence / emission guide hole 30 formed therein and a VCM magnet 12 mounted on an outer circumferential surface thereof, and a suspension base 10. First and second suspensions 11 and 31 extending vertically side by side at 10), and a first slider 18 elastically supported by the first suspension 11 via a gimbal 19; The second slider 38 and the tip 16a are elastically supported by the second suspension 31 via the gimbal (not shown), and the suspension base 10 and the first slider 18 are formed. A first optical fiber 16 installed between the second optical fiber 16 and a tip (not shown) formed between the suspension base 10 and the second slider 38 and the light incident / emitting light. A total reflection mirror and a light wavelength selective mirror 14 and 34 are installed in the guide hole 30 vertically and side by side. The first and second optocouplers 15 and 35 coupled to one side of the first and second optical fibers 16 and 36 are vertically parallel to the light incidence / emission guide holes 30 of the suspension base 10, respectively. It is mounted. The suspension base 10 is pivoted by the rotational force generated from the VCM magnet 12. The VCM magnet 12 is mounted to the suspension base 10 opposite to a coil (not shown) installed in the disc drive. The VCM magnet 12 pivots the suspension base 10 by generating electromagnetic force by forming an electromagnetic circuit together with the coil when a current is applied to the coil in the disc drive device. When the suspension base 10 is pivoted, the first and second suspensions 11 and 31 are pivoted around the suspension base 10 and the tips mounted on the first and second sliders 18 and 38 are rotated. The upper disk 1 and the lower disk 1 are accessed by the first and second suspensions 11 and 31, respectively.

The first and second suspensions 11 and 31 elastically support the first and second sliders 18 and 38, respectively, and apply a predetermined load to each of the first and second sliders 18 and 38, respectively. And the height of the floating of the second sliders 18 and 38. The first and second sliders 18 and 38 are injured by the air flow generated as the disk 1 rotates and serve to injure the tips mounted thereon, respectively. Accordingly, these first and second suspensions 11 and 31 and the first and second sliders 18 and 38 allow the tips of the disk 1 to maintain a small floating height from the surface of the disk 1 when the disk is rotated. The floating height of the tips is controlled within the wavelength of light from the disk 1 so that the recording surface can be accessed. In detail, when the disk 1 starts to rotate, a flow velocity occurs on the surface of the disk 1. The air flow generated by the flow rate is represented by the floating force of the slider 18. This airflow causes the first and second sliders 18 and 38 to rise from the surface of the disc 1 at the moment they withstand the loads applied from the first and second suspensions 11 and 31 and their own loads, respectively. do. When the disk 1 rotates at a constant speed, the amount of air flow becomes constant, so that the first and second sliders 18 and 38 maintain a constant floating height. Here, the applied height of the first and second suspensions 10 is determined so that the floating height of the first and second sliders 18 and 38 is maintained at a predetermined height from the disk 1.

The total reflection mirror 14 is installed between the optical wavelength selective mirror 34 and the first optical coupler 15 so as to totally reflect the light transmitted through the optical wavelength selective mirror 34 toward the first optical coupler 15, and also the first optical beam. It serves to totally reflect the reflected light incident from the coupler 15 toward the light wavelength selective mirror 34. The light wavelength selective mirror 34 selectively transmits or reflects incident light according to the wavelength of light. The optical wavelength selective mirror 34 is installed between the total reflection mirror 14 and the second optical coupler 35 to direct incident light toward the total reflection mirror 14 according to the wavelength of the light incident through the light incidence / emission guide hole 30. The light is transmitted or totally reflected toward the second optocoupler 35. Therefore, when the disk to be accessed currently is the upper disk 1, only the upper disk 1 is accessed when the wavelength of the light irradiated from the external light source is adjusted as the wavelength of the light transmitted by the optical wavelength selective mirror 34 to transmit the wavelength of the incident light. can do. On the contrary, when the disk to be accessed currently is the lower disk 1, when the wavelength of the light irradiated from the external light source is adjusted as the wavelength of the light reflecting the wavelength of the incident light by the optical wavelength selective mirror 34, only the lower disk 1 Will be accessible. In addition, the optical wavelength selective mirror 34 reflects the reflected light incident from the second optical coupler 35 toward the external photodetector through the light incidence / emission guide hole 30. These total reflection mirrors 14 and light wavelength selective mirrors 34 allow the external light source and external photodetector to be fixed within the disc drive without following the sliders 18 and 38 and tips.

The first and second optocouplers 15 and 35 serve to couple one end of the first and second optical fibers 16 and 36 to the suspension base 10, respectively. In addition, the first and second optocouplers 15 and 35 guide light incident from the total reflection mirror 14 and the light wavelength selective mirror 34 toward the first and second optical fibers 16 and 36, respectively. Reflected light incident from the first and second optical fibers 16 and 36 is directed toward the total reflection mirror 14 and the light wavelength selective mirror 34.

One side of the first optical fiber 16 is coupled to the first optocoupler 15 and is bent over the hole 18a formed in the first slider 18 via the top surface of the first suspension 11 to form the hole 18a. It will penetrate through. The tip 16a formed at the end of the first optical fiber 16 is positioned almost perpendicular to the upper disk 1. One side of the second optical fiber 36 is coupled to the second optical coupler 35 and is bent over the hole formed in the second slider 38 via the upper surface of the second suspension 31 to penetrate the hole. The tip formed at the end of the second optical fiber 36 is positioned almost perpendicular to the lower disk 1.

Since the structure and function of the head portion 100 for accessing the lower disk 1 are substantially the same as those of the head portion 100 for accessing the upper disk 1, the detailed description is omitted, and the upper disk ( The configuration and function of the head unit 100 for accessing 1) will be described in detail.

The first optical fiber 16 transmits light incident through the first optocoupler 15 to the tip 16a and provides a light transmission path to transmit the reflected light received from the tip 16a toward the coupler 26. do.

The end of the tip 16a for accessing the upper disk 10 is sharply processed to have a conical shape. The tip 16a is used to rise to a small floating height from the disk 1 by the first slider 18 at the time of recording, and receives the light incident on itself via the optical fiber 16 in the form of near-field light. Condensed on the recording film to form a microscopic recording mark. In addition, during the reproduction, the tip 16a receives the reflected light reflected from the disk 1 onto the recording film of the disk 1, and receives the reflected light reflected from the recording film and traveling back to the optical path. At this time, the received reflected light is totally reflected toward the external photodetector by the total reflection mirror 14 via the optical fiber 16 and the optical coupler 14 backing the optical path. The external photodetector then converts the reflected light into an electrical signal.

Meanwhile, in the embodiment of the present invention, the cartridge containing two disks 1 is illustrated, but as can be seen in the embodiment, two or more disks 1 may be stored so that each disk may be recorded / reproduced. .

As described above, the near-field recording / reproducing cartridge having a plurality of disks according to the present invention includes a disk having a high density recording capacity to be recorded / reproduced by a near field, tips for accessing the disks, and A lift height control means for controlling the lift height of the tips and a transfer means for transporting the tips in the inner / outer direction of the disc are provided to have a high density recording capacity and to improve the playback speed.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (10)

At least two recording media, Optical transmission means for forming an optical transmission path of incident light incident on the respective recording media and reflected light reflected from the respective recording media; At least two light concentrating means for concentrating the light transmitted via the optical transmission path to the recording medium and for guiding the light reflected from the recording medium to the optical transmission means; Floating height control means for floating the optical focusing means within a small distance from the recording medium; Transfer means for transferring the floating height control means to an arbitrary position on the recording medium; And a recording medium driving means for rotating the recording medium. The method of claim 1, The recording medium, the optical transmission means, the optical focusing means, the floating height control means, the conveying means and the recording medium driving means is provided with a housing of the airtight structure further installed therein A cartridge for near field recording / playback having a disc. The method of claim 1, The optical transmission means includes a total reflection mirror for totally reflecting light toward the uppermost recording medium and totally reflecting the reflected light reflected from the uppermost recording medium toward the outside; An uppermost layer optical fiber for transmitting the light incident from the total reflection mirror to the light converging means facing the uppermost layer recording medium; An optical wavelength selective mirror for reflecting light toward the lower recording medium and reflecting the reflected light reflected from the lower recording medium toward the outside; And a lower layer optical fiber for transmitting light incident from the optical wavelength selective mirror to the light converging means opposite to the lower layer recording medium. The method of claim 3, wherein The light converging means has a conical tip in which the ends of the optical fibers are sharply processed. A near field recording / reproducing cartridge having a plurality of discs. The method of claim 3, wherein The optical transmission means includes a top layer optical coupling member for fixing the top layer optical fiber to face the total reflection mirror; And a lower layer optical coupling member for fixing the lower layer optical fiber to face the optical wavelength selective mirror. The method of claim 3, wherein And said total reflection mirror and said optical wavelength selective mirror are provided on a rotation axis of said floating height control means. The method of claim 1, The floating height control means includes at least two head sliders for supporting each of the light converging means; And at least two suspensions for elastically supporting and applying a predetermined load to each of the head sliders. The method of claim 7, wherein The floating height control means is provided between the head slider and the suspension further comprises a gimbal member for transmitting the load of the suspension to the head slider, a near field recording / reproducing cartridge having a plurality of disks . The method of claim 1, And the conveying means has permanent magnet means attached to the floating height control means to generate a rotational force by forming an external coil and an electromagnetic circuit. The method of claim 1, The recording medium driving means includes a flange installed on the inner diameter side of the recording medium and the rotating shaft is formed; A near field recording / reproducing cartridge having a plurality of disks, characterized by comprising permanent magnet means installed adjacent to said flange to generate magnetic flux.