JPS62141692A - Optical information recorder - Google Patents

Abstract

PURPOSE:To scale down a device and to cut down its cost by fixing an optical information recording medium on a drive means including a spindle motor so that said medium cannot be removed and arranging the recording medium in a space having a dust-prevention effect. CONSTITUTION:The optical information recording medium 2 is placed in the recessed part of a hub 10 secured on the shaft 8 of a spindle motor 30, and pressurized and fixed by a clamp plate 3 and a claw screw 4 between them. In order to prevent the entry of dust in a machine frame 1, a screw for fixing the cover 36 of the device is tightened by a packing 35, and the packing 35 is brought into pressure-contacted with the frame 1 and the cover 36. A known control circuit irradiates laser light from a laser diode 20 in accordance with a signal, and the light is focused on the recording layer 2b of the medium 2. Then the recording layer 2b is heated more than a Curie point. A magnetic field in the part is inverted by the magnetic pole of a bias coil 16, and information is recorded as a bit about 1mum in length in the recording layer 2b. Accordingly a distance A from the recording layer 2b to the bias coil 16 is short, and a small coil suffices accordingly.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention uses an optical information recording medium, records information by irradiating the member with light, and detects the optical signal acting on the member with a light receiving means. The present invention relates to an optical information recording device having an entire structure for reproduction.

[Summary of the invention]

The present invention provides that in the optical information recording device, the optical information recording medium is fixed to a spindle motor that is a driving means for the member, and that in this structure, the recording medium, the optical head, and the light receiving means are completely protected from the outside air. It is arranged in a space that has at least a dustproof effect, and furthermore, these structures are adopted in an apparatus using a transmission type optical information recording medium.

[Prior art]

Conventional optical information recording devices are generally of a type in which an optical information recording medium is placed in a cartridge, and the cartridge is removably attached to the device.

This is the optical information recording medium referred to in the document OPTICALME.
MORY NEWS (JULY-AUGUST 1
985) (7) P,,A As stated in E6, it generally has a thick three-layer structure, and as will be described later,
Even if dust or the like adheres to the medium, it will not affect the reliability of recording and reproducing information due to the distance from the recording surface. Therefore, the cartridge is designed so that all users can freely attach and detach it, and it is not possible to remove it from the device. It had the great advantage that there was no effect even if it was stored in a storage medium, and that it was possible to process a large amount of data with a recording device by replacing the recorded medium with an unused one. .

[Problems and objects to be solved by the invention] However, in the conventional type in which the recording medium arranged in the cartridge can be attached to and detached from the device, a special arrangement is required for the attachment and detachment device. This not only complicates the mechanism, but also greatly affects the cost and size of the entire device.

In addition, all users must replace the cartridge and
It does not require a large amount of information that is not limited in capacity. In addition, compared to well-known hard disk drives, optical information recording devices can record a large amount of information on the same area of the medium, so when recording the same amount of information, the size of the medium can be smaller than that of a hard disk. It has elements that allow the recording device to be made smaller and lower in price. The present invention aims to miniaturize and reduce the cost of these devices.

[Means for solving problems]

In view of the above-mentioned points, the optical information recording device of the present invention is provided such that the optical information recording medium is fixed in a non-removable manner to a driving means including a full spindle motor, and the recording medium is placed in a space having at least a dustproof effect against the outside air. It is characterized by being placed inside.

[For production]

According to the above configuration of the present invention, the optical information recording medium, an optical head that irradiates the optical information recording medium with light,
The light-receiving means for receiving the original signal acting on the optical information recording medium is arranged in a space that is at least dust-proof against all outside air, so it is less susceptible to dust than conventional optical information recording devices. Because it can be difficult to
Optical information recording media It is possible to eliminate the dust protection measures found in conventional types of optical information recording media, or to change them to simpler methods, reducing costs and downsizing. has advantages. For example, as mentioned above, the structure of an optical information recording medium is a transmissive type, as described in the document OPTICAL MEMORY NEWS.
(JULY-AUGUST 1985) PAGE
6, it has a three-layer structure in which a recording layer is provided on top of a substrate, and a protective cover of approximately the same thickness as the substrate is placed on top of this recording layer. This is for the purpose of preventing the recording layer from deteriorating as is well known.
Since the laser beam from the optical head is focused on the recording layer, even if there is dust on the substrate or cover, the diameter of the beam is large in that area, so no noise will be caused by dust during information recording or reproduction. This is for the reason. However, as mentioned above, this general optical information recording medium with a three-layer structure takes too much consideration to dust, and the disk becomes thicker. Since the distance to 16) in Figure 2 of the invention (dimension A in Figure 2) is longer,
The magnetic field strength received by the recording layer becomes weaker than the magnetic field strength generated by the bias coil, and when recording all information, the laser beam focuses on the recording f-, and the magnetic field generated by the bias coil However, even if an attempt is made to reverse the magnetism of the recording layer, the reversal is not carried out satisfactorily. For this reason, when using a medium with the three-layer structure, the bias coil must be made larger, the increased weight of the coil affects the access time, the heat generated by the coil deforms the disk, the current consumption increases, and the bias coil becomes larger. When the medium is placed in the known cartridge, there are a number of drawbacks, such as the overall thickness of the device due to the cartridge.

In one embodiment of the present invention, all of these points are improved.Ninthly, the cartridge is abolished, and the upper cover of the optical information recording medium is completely abolished as shown in FIG. 4 of the present invention, and the same cartridge and cover are used. In order to achieve this effect, a transmissive type is used in which a thin protective film is provided on top of the recording layer. In such a case, since the layer from the recording layer to the top of the protective film is very thin, it is difficult to protect the area from the recording layer to the top of the protective film. If dust is placed on the film, even a small dust with a diameter of several micrometers near the focal point of the laser will affect the optical signal, causing a decrease in reliability as an information recording device, so in the present invention, A major feature is that the medium is fixed to the drive means of an optical information recording device so that dust does not adhere to the medium, and furthermore, it is placed in a space within the device that is dust-proof against at least the outside air.

〔Example〕

An embodiment of the present invention will be described in detail with reference to the drawings, but well-known parts will be simplified.

FIG. 1 is an external perspective view showing one embodiment of the present invention.
The cover 36 of the device is removed so that the inside of the device can be explained. FIG. 2 is an assembled sectional view of FIG. 1. FIG. 3 is an optical system block diagram mainly showing the optical system of the present invention, and FIG. 4 is a sectional view of an optical information recording medium used in the present invention as an example. In all the figures, 1 is a machine frame of the device made of aluminum or the like, and includes the spindle motor 30 and the rail 6.
etc. are listed. 2 is an optical information recording medium;
The hub 10 is placed in a recessed portion of a hub 10 that is fixed to the shaft 8 of a spindle motor 30, which is a driving means of the spindle motor 30, and is fixedly pressed between the two by a clamp plate 3 and a clamp screw 4. Reference numeral 5 denotes a carriage, which holds an optical head 17 incorporating a well-known actuator that moves an objective lens 23 and the objective lens 26 for focus control and track control, and partially includes a bearing 18 and a photodiode 7 as a light receiving means. It has a light receiving means holding part 5a that holds the light receiving means. 6 is held in the machine frame 1 by a rail that fits into a bearing 18 provided on the carriage 5. 9 is the configuration of the spindle motor 30 JJ!
The rotor magnet 11, which is made of L element, has a well-known magnetic fluid seal to prevent dust from entering from the outside. 12,
121: (A ball bearing whose outer ring is fixed to a cylindrical part provided in the machine frame 1, and whose inner ring part supports the shaft 8. 13 is made of a magnetic material, and the coil 14 and the shaft 8 are connected to each other. A thrust bearing 15 is provided.A bias coil 16 is fixed to the light-receiving means holding portion 5a of the carriage 5, and is located at a distance A from the recording layer as shown in FIG. 2, and acts during information recording.

20 is a laser diode, 21 is a prism, and the junction surface 22 is a polarizing beam splitter. 23 is the objective lens, 24 is a knife for focus control, 25 is a condenser lens, 26 is a ninth photodiode for detecting servo signals for focus control and track control, 27 is a collimator lens, and 35 is the machine frame. This is a gasket placed on the end face of the machine frame 1 to prevent dust contained in the outside air from entering into the machine frame 1, and by tightening a screw (not shown) for fixing the cover 36 of the device. It is in pressure contact with the machine frame 1 and the cover 36. 3
7 is a polarizing plate.

The operation will be explained.

When a power switch (not shown) is turned ON, the spindle motor 30 rotates. Since the optical information recording medium 2 is fixed to the shaft 8 of the spindle motor, the medium 2 also rotates. Love! 4, a well-known control circuit (
(not shown), laser light is irradiated from the laser diode 20 according to the signal, and the collimator lens 2
7. The light is focused on the recording layer 2b of the medium 2 through the prism 21 and the objective lens 23, and information is recorded. On the other hand, a part of the light is reflected by the recording rfI 26i, separated by the polarizing beam splitter 22, passed through the knife lens 24 and the condensing lens 25t, and detected by the photodiode 26.
This signal becomes the servo signal for the focus and track control. In this manner, since the laser beam is accurately focused on a predetermined track and the entire recording layer is heated to more than one point, the magnetic field is reversed in that portion by the magnetic pole generated by the bias coil 160, so that all information can be recorded. The information is approximately 1 μm in both width and length.
The shape of this bit is approximately 1/10 of the bit shape of the hard disk.
Therefore, the optical information recording medium can record about 10 times more information than a hard disk in the same area.

When reproducing information, the optical path is the same as described above, but the laser beam from the objective lens 23 is lowered in power than during recording, and the next track is continuously irradiated with laser light. At this time, since the recorded portion and the unrecorded portion have different Faraday rotation angles, the substrate 2a of the medium 2.

The laser beam transmitted through the recording layer 2b and the protective film 2ci passes through the fully polarizing plate 37 and is detected by the photodiode 7 as the presence or absence of the bit, allowing the recorded information to be read.

〔Effect of the invention〕

As described in detail above, in one embodiment of the present invention, the thin optical information recording medium 2 in which the thin preservation film 2ci is provided on the upper part of the recording layer 2b shown in FIG. 4 is used.
The distance A (shown in Fig. 2) from 2b to the bias coil 16 can be shortened compared to devices using conventional recording media, which improves magnetic efficiency and requires a small coil, reducing the weight of the coil. So, carriage 50 weight 1
In addition to being able to speed up the access time of the ninth drive, which can be made as light as possible, it also has effects such as reducing heat generation in the bias coil 16, reducing current consumption, and reducing the thickness of the entire drive.

As described above, when this thin optical information recording medium is used, the protective film 2 is removed from the recording jgi 2 b.
Since the upper part of the protective film 2c is very thin, even if dust is placed on the protective film 2c, even the smallest dust near the focal point of the laser will completely affect the optical signal, reducing reliability as an information recording device. Therefore, in the present invention, in order to prevent dust from adhering to the optical information recording medium 2, the optical information recording medium 2 is fixed to the driving means of the optical information recording apparatus in a clean room, and the optical information recording medium 2 is This is an effect of arranging the head 17 and the light-receiving means 7 within the device which has a dust-proofing effect against the outside air, and eliminating the cartridge.

Further, as an embodiment of the present invention, the optical information recording medium 2
A transmission type medium in which light receiving means 7 is provided on the front side of the optical head 17.4 and the light passes through the medium 2 has been described in detail.
As mentioned above, since it is located between the optical head 17 and the light receiving means 7, with this structure, it is difficult to attach and detach a thick cartridge equipped with a conventional medium between the two. It is disadvantageous both structurally and dimensionally. The present invention in which the medium 2 is fixed has particularly great effects in these respects, but it is also applicable to the type used on a reflective medium in which the well-known optical head and light receiving means are placed on the 10,000' side of the medium. The invention is applicable, and the same effect as the present invention can be easily obtained even with a structure in which a medium using a conventional thick protective cover is fixed to the driving means, and does not depart from the gist of the present invention. .

[Brief explanation of drawings]

FIG. 1 is an external perspective view showing one embodiment of the present invention. FIG. 2 is an assembled sectional view of FIG. 1. FIG. 3 is an optical system block diagram mainly showing the optical system of the present invention. FIG. 4 is a sectional view of the optical information recording medium used in the present invention. 1 is the machine frame 2 is the optical information recording medium 7 is the light receiving means 17 is the optical head 30 is the driving means 1...Fuku・袢2...LHa city 6 Xunshu3...Crank 9th order 4・...The crank is too fast...1,000 issons. G...Rail Figure 71 Ta1.・Carriage 7...notoge is -p. IG...Bahia 2I...Gusos°A 22...44'' Zippy phrase Zugusotta 23...i size 4 kere/su°. 2nd move...gui 7e zoji. b Light #thread block diagram name 3 times 2,,, MA City Shingumochi 2k...Puno Bun Tray F Optical Bare 4 Kill 1 Hi Amu Hino's folded surface diagram band 4-Figure

Claims (2)

[Claims] (1) An optical information recording medium fixed to a driving means including a spindle motor, an optical head that irradiates light onto the optical information recording medium, and a light receiving means that receives an optical signal acting on the optical information recording medium. An optical information recording device comprising: (2) The optical information recording device according to claim 1, wherein a transmission type is used as the optical information recording medium.