KR900006957B1 - Recording/reproducing optical head units - Google Patents

Abstract

A reflect mirror (13) having reflective surface (13") is placed between a collimator lens (3) and a beam spliter (4). The laser (12) passed through the collimator lens is devided to read/ write laser (12') and servo control laser (12") by the surfaces (13',13") of the mirror. The laser divided by two focuses on the disc with certain gap (d). A laser sensor plate (9) having a read/ write laser sensor (9a) and a servo laser sensro (9a') receives the reflected lasers. The reference track recorded the carrier frequency is placed on the inner and outer side of the disc respectively so that the servo control laser follows the track instead of the guide groove.

Description

Optical head device for recording and reproducing information signals of optical discs without guide grooves

1 is an explanatory diagram showing a conventional optical head device.

2 is a perspective view showing an optical disk used in a conventional optical head device. b is an enlarged longitudinal sectional view of portion A of a;

3 is an explanatory view showing an optical head device according to the present invention.

4 is a perspective view showing an optical disk used in the optical head device of the present invention.

* Explanation of symbols for main parts of the drawings

1 Modulator 2 Laser Diode

3: collimator lens 4: beam splitter

λ 파장판 6 : 대물렌즈5:

λ wave plate 6: objective lens

7: condenser lens 8: cylindrical lens

9: Light receiving plate 9 ', 9a, 9a': Light receiving sensor

10: objective lens driving unit 10 ': tracking coil

10 ": Focus coil 11: Disc

11a: reference track 12, 12 ', 12 ": laser light

13: reflector 13 ': surface

13 ": reflective surface.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical head apparatus for recording and reproducing an information signal by firing a laser beam onto a disc. In particular, the information of an optical disc without a guide groove that enables recording and reproduction of an information signal without providing a guide groove on the disc. An optical head device for recording and reproducing.

파장판(5)과, 상기

파장판(5)을 통과한 레이저광(12)을 한점에 모아 디스크(11)에 입사시키고, 디시크(11)에서 반사된 레이저광(12)은 평행광으로 바꾸는 대물렌즈(6)와, 상기 비임스프리터(4)에서 분리된 반사레이저광(12)을 수렴광으로 변환하는 집광렌즈(7)와, 상기 집광렌즈(7)를 통한 수렴광으로 대물렌즈(6)의 초점오차신호를 검출하기 위한 원통형렌즈(8)와, 상기 원통형렌즈(8)를 통한 레이저광(12)을 수광하는 수강쎈서(9')가 설치된 수광판(9)과, 상기 수광판(9)의 출력신호에 따라 트래킹코일(10') 및 초점코일(10")에 인가되는 신호로 서어보제어를 하는 대물렌즈구동부(10)로 구성되어 있다.In the conventional optical head apparatus, as shown in FIG. 1, a laser diode (2) which emits the laser light (12) as a signal output from the modulator (1) according to the input recording information signal, the reproduction mode signal, and the erase mode signal. ), A collimator lens 3 for converting laser light 12 emitted from the laser diode 2, that is, divergent light into parallel light, and laser light at one side and the other side of the laser diode 2 Beam splitter 4 for separating the laser beam 12 emitted from the laser beam 12 and the laser beam 12 reflected from the disk 11 and

Wave plate 5 and the above

An objective lens 6 which collects the laser light 12 passing through the wavelength plate 5 at one point and enters the disk 11, and the laser light 12 reflected by the disc 11 is converted into parallel light; A focusing lens 7 for converting the reflected laser light 12 separated from the beam splitter 4 into a converged light, and a focus error signal of the objective lens 6 is detected by the converged light through the condensing lens 7. A light receiving plate 9 provided with a cylindrical lens 8, a receiving sequence 9 'for receiving a laser beam 12 through the cylindrical lens 8, and an output signal of the light receiving plate 9 Therefore, it is composed of an objective lens driver 10 for controlling the servo with a signal applied to the tracking coil 10 'and the focus coil 10 ".

In the disk 11 for recording and reproducing the information signal by such an optical head device, the guide groove 11 'is formed in the disk 11 in a concentric or swirling manner as shown in a and b of FIG. Between the guide grooves 11 ', a track 11' for recording and reproducing the information signal is set.

λ 파장판(5), 대물렌즈(6)를 거쳐 디스크(11)의 한점에 입사되게 되는데, 이때 하나의 레이저광(12)을 대물렌즈(6) 및

λ 파장판(5), 비임스프리터(4), 집광렌즈(7), 원통형렌즈(8)를 통해 수광판(9)으로 수광하여 레이저광(12)이 트랙(11")에 정확히 입사되게 서어브제어를 수행하고, 트랙(11")에 입사되는 레이저광(12)으로는 트랙(11")에 정보신호를 기록시키거나 되는 그 트랙(11")에서 반사되는 광을 수광판(9)의 수광센서(9')로 수광하여 트랙(11")에 기록되어 있는 정보신호를 재생하게된다.In the conventional optical head device configured as described above, the laser light 12 is emitted from the laser diode 2 by a signal output from the modulator 1 according to the recording information signal, the reproduction mode signal, and the erasing mode signal. 12, the collimator lens (3) and beam splitter (4),

Through the λ wave plate 5 and the objective lens 6, the light is incident on one point of the disk 11. At this time, one laser beam 12 is applied to the objective lens 6 and

The light is received by the light receiving plate 9 through the? wavelength plate 5, the beam splitter 4, the condenser lens 7, and the cylindrical lens 8 so that the laser beam 12 is accurately incident on the track 11 ". The laser beam 12 incident to the track 11 " is used to control the light reflected from the track 11 " to record an information signal on the track 11 " The light is received by the light receiving sensor 9 'to reproduce the information signal recorded on the track 11 ".

정도의 면적을 차지하므로 디스크(11)에의 정보신호기록밀도가 낮은 결함이 있었다.However, such a conventional apparatus must time-division one laser beam 12 so as to alternately enter the guide groove 11 'and the track 11 "of the disc 11, and also to stand on the disc 11. The guide groove 11 'for performing the beam control must be formed, so that the manufacturing cost of the disk 11 increases, and the guide groove 11'

Since it occupies an area of about a degree, there is a defect that the information signal recording density on the disc 11 is low.

In view of such a conventional deficiency, the present invention produces two laser beams, a sub-control laser beam and an information signal recording / reproducing laser beam, while maintaining a constant distance with an optical head device. Set the reference track that recorded the carrier frequency in advance in the area corresponding to the rotation, and perform the sub control while tracking the information signal recording track spaced at regular intervals based on the reference track and the reference track with the servo control laser beam. The information signal recording and reproducing laser beam records and reproduces the information signal while accurately tracking the track according to the servo control by the servo control laser beam. Invented so that information signals can be recorded and reproduced without being formed, and according to the accompanying drawings Described in detail as follows.

λ 파장판(5), 대물렌즈(6), 집광렌즈(7), 원통형렌즈(8), 수광판(9), 대물렌즈구동부(10)로 구성되어 디스크(11)에 정보신호를 기록 및 재생하는 광학 헤드장치에 있어서, 상기 콜리메이터렌즈(3)를 통과한 레이저광(12)의 일부는 표면(13')에서 반사시켜 정보신호기록재생용 레이저광(12')을 만들고, 나머지는 반사면(13")에서 반사시켜 서어보제어용 레이저광(12")을 만들어 그 레이저광(12')(12")이 상흐 일정간격(d)을 유지하면서 디스크(11)에 입사되게 하는 반사경(13)과, 상기 디스크(11)에서 반사되어 대물렌즈(6) 및

λ 파장판(5), 비임스프리터(4), 집광렌즈(7), 원통형렌즈(8)를 거친 레이저광(12')(12")을 수광하는 수광센서(9a)(9a') 가 설치된 수광판(9)으로 구성한 것으로, 상기에서 수광소자(9a')로 수광되는 레이저광(12")에 따라 대물렌즈구동부(10)의 트래킹코일(10') 및 초점코일(10")에 신호를 인가하여 서어보제어를 수행하게 한다.3 is an explanatory view showing the optical head device according to the present invention, as shown in the laser diode 2 and the collimator lens 3 for emitting the laser light 12 in accordance with the output signal of the modulator 1. , Beam splitter (4),

a wavelength plate 5, an objective lens 6, a condenser lens 7, a cylindrical lens 8, a light receiving plate 9, and an objective lens driver 10 to record information signals on the disc 11 In the optical head apparatus for reproducing, a part of the laser light 12 passing through the collimator lens 3 is reflected on the surface 13 'to make the laser light 12' for information signal recording and reproduction, and the other half Reflector that reflects from the slope 13 "to make the servo control laser light 12" and makes the laser light 12 ', 12 "enter the disc 11 while maintaining the constant distance d. 13), reflected from the disk 11 and the objective lens 6 and

The light receiving sensors 9a and 9a 'which receive the laser light 12' and 12 "passing through the? wavelength plate 5, the beam splitter 4, the condenser lens 7, and the cylindrical lens 8 are provided. It consists of a light receiving plate 9, and signals to the tracking coil 10 'and the focusing coil 10 "of the objective lens driver 10 according to the laser light 12" received by the light receiving element 9a'. Apply servo to perform servo control.

Then, as shown in FIG. 4, the disc 11 for recording and reproducing the information signal with the optical head apparatus according to the present invention forms guide grooves only at the portions corresponding to one rotation of the outermost and innermost sides, and conveys them. The reference track 11a for recording the frequency in advance is formed.

If described in detail the effects of the present invention configured as described above.

λ 파장판(5), 대물렌즈(6)를 거쳐 상호 일정간격(d)을 유지하면서 디스크(11)에 입사된다. 이때, 정보신호를 디스크(11)의 최내주의 제1트랙인 기준트랙(11a)에 기록할때는 그 최내주의 안내홈을 이용하여 종래의 기록방식과 동일하게 기록한다. 즉, 기록재생용 레이저광(12')이 그 기준트랙(11a)을 트래킹하면서 정보신호를 기록하게 된다.First, when a recording information signal is input to the modulator 1 when a predetermined information signal is recorded on the disk 11, the modulator 1 modulates the recording information signal and then applies the laser information to the laser diode 2 to generate a laser signal. The diode 2 emits a laser light 12 whose intensity varies according to the recording information signal, and the emitted laser light 12 is converted into parallel light through the collimator lens 3 and then applied to the reflecting mirror 13. That is, a part of the laser beam 12 is reflected from the surface 13 'of the reflector 13 to be a laser beam 12' for information signal recording and reproduction, and the other part is refracted and the inside of the reflector 13 is refracted. After entering the laser beam, it is reflected from the reflecting surface 13 "and becomes the servo control laser light 12", and the separated laser light 12 'and 12 "are beam splitter 4 and

The light is incident on the disk 11 while maintaining a constant distance d from each other via the? wavelength plate 5 and the objective lens 6. At this time, when the information signal is recorded on the reference track 11a, which is the first track of the innermost circumference of the disc 11, the information signal is recorded in the same manner as the conventional recording method using the guide groove of the innermost circumference. In other words, the recording / reproducing laser beam 12 'records the information signal while tracking the reference track 11a.

λ 파장판(5), 비임스프리터(4), 집광렌즈(7), 원통형롄즈(8)를 거친 후 수광판(9)의 수광센서(9a')에 수광되며, 그 수광된 레이저광(12")에 따라 대물렌즈구동부(10)의 트래킹코일(10') 및 초점코일(10")에 신호를 인가하여 레이저광(12")이 기준트랙(11a)을 정확히 트래킹하게 서어보제어를 수행하며, 이와같이 레이저광(12")이 기준트랙(11a)을 트래킹할때 레이저광(12')은 서어보제어용 레이저광(12")과 일정간격(d)을 유지하므로 기준트랙(11a)과 일정간격(d) 떨어진 트랙 즉, 제2트랙을트래킹하면서 정보신호를 기록하게 된다.Subsequently, when the information signal is recorded on the second track from the innermost side of the disc 11, the servo control laser beam 12 "tracks the reference track 11a while the carrier frequency is recorded on the reference track 11a. And reflected laser light 12 "

After passing through the λ wave plate 5, the beam splitter 4, the condenser lens 7, and the cylindrical lianz 8, it is received by the light receiving sensor 9a ′ of the light receiving plate 9, and the received laser light 12 A servo is applied to the tracking coil 10 'and the focus coil 10 "of the objective lens driver 10 according to " to perform the servo control so that the laser beam 12 " accurately tracks the reference track 11a. In this way, when the laser light 12 "tracks the reference track 11a, the laser light 12 'maintains a constant distance d from the servo control laser light 12". The information signal is recorded while tracking a track spaced apart from the predetermined interval d, that is, the second track.

In this way, while the laser light 12 "tracks the reference track 11a corresponding to one rotation, the laser light 12 'tracks a portion away from the reference track 11a and records an information signal. After that, the laser light 12 "is reflected while tracking the track on which the information signal is recorded, and then enters the light receiving sensor 9a 'to perform the servo control as described above, and the laser light 12' receives the information signal. The information signal is recorded while tracking a portion separated from the recorded track by a predetermined interval, so that the information signal is recorded on the disc 11 in a portion separated inward or outward by a predetermined interval d relative to the reference track 11a.

When the information signal is recorded on the disc 11 and reproduced as described above, the servo control laser light 12 "reflects the laser light 12 reflected while tracking the track track on which the reference track 11a and the information signal are recorded. Servo control is performed with "), and the laser beam 12 'tracks the track on which the information signal is recorded while maintaining a constant distance d with the laser beam 12 " The information signal received and recorded by the light receiving sensor 9a of (9) is reproduced.

Since the intensity of the reflected laser light 12 "depends on the level of the recorded information signal, the servo control is sampled only when the intensity of the reflected laser light 12" is high.

As described above, the present invention records and reproduces the information signal without forming guide grooves in the portions other than the innermost and outermost portions of the disc, so that the information signal recording density on the disc is high and the production cost of the disc is high. There is a saving effect.

Claims (1)

The laser light 12 generated by the modulator 1 from the laser diode 2 is collimated with the collimator lens 3, the beam splitter 4,

The objective lens 6 includes the laser light 12 that is focused on the disk 11 through the wavelength plate 5 and the objective lens 6 and then reflected from the disk 11.

The light incident plate 9 is incident on the light receiving plate 9 through the λ wave plate 5, the beam splitter 4, the light collecting lens 7, and the cylindrical lens 8, and according to the output signal of the light receiving plate 9, 10. In the optical head apparatus for performing servo control in the recording and reproducing on the disc 11, the reflector 13 having a reflecting surface 13 "between the collimator lens 3 and the beam splitter 4; The laser light 12 through the collimator lens 3 is used for recording and reproducing the laser light l2 'and the servo by the surface 13' and the reflecting surface 13 "of the reflector 13. It is separated into a control laser light 12 "and focused on the disk 11 in the same manner as above while maintaining a predetermined distance d, and the light receiving plate 9 for the reproduction light receiving sensor 9a and The servo light receiving sensor 9a 'is provided so that the recording / reproducing laser light 12' and the servo control laser light 12 " The way to the light receiving sensor (9a), (9a ') for each incident optical head device to be recorded groove information of the optical disk without guidance signal, characterized in that configured on reproduction.

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