USO0RE40908E

(19) United States (12) Reissued Patent

(10) Patent Number:

Miyagawa et a]. (54)

(45) Date of Reissued Patent:

OPTICAL RECORDING/REPRODUCING APPARATUS FOR OPTICAL DISKS WITH VARIOUS DISK SUBSTRATE THICKNESS

JPTAT52T153705'

Yasuhiro Gotoh, Kadoma JP

_

(57)

Related US‘ Patent Documents

(63)

ratus includes one or a plurality of optical heads having a

plurality of objective lenses Whose aberrations have respec tively been corrected for a plurality of disc substrates of different thicknesses, a cartridge for enclosing the optical disc, a discrimination hole Which is formed on the cartridge, and a sensor for detecting the opening/closing state of the

51235581

Aug. 10, 1993 07/740,629 Aug, 5, 1991 _

ABSTRACT

[An optical disc apparatus for recording, reproducing or erasing an information signal by converging a light ?ux onto a recording layer through a transparent substrate. The appa

NOV‘ 22’ 1999

. . U'S' APP119m1°¥1S1

_

Primary ExamineriNabrl Z Hrndl (74) Attorney, Agent, or FirmiDickinson & Wright, PLLC

(21) Appl. No.: 09/609,829

Relssue 0T3 (64) Patent NO? Issued: Appl. No.: Filed;

(Continued) _

( ) (73) AssigneeZ Panasonic Corporation, Osaka (JP)

_ Flled:

Sep. 8, 2009

OTHER PUBLICATIONS Japanese Patent Abstract, “Optical Disc Regenerator”, vol. 2, N0. 32, Feb. 28, 1978, [Mitsubishi Denki K.K.(1)];

(75) Inventors: Naoyasu Miyagawa, Suita (JP);

(22)

US RE40,908 E

discrimination hole and for generating a discrimination sig nal. In accordance With the result of the discrimination as to

_

Contlnuatlon OTaPPTTCaTTOn N°~ 08/396,981, ?led on Man 1’

the thickness of the loaded optical disc, the objective lens, in

1995 ’ now Pat‘ NO‘ Re‘ 36’445 '

Which the occurrence of the aberration is smallest, is used, so

(30)

Foreign Application Priority Data

that the information signal can preferably be recorded, reproduced or erased onto/from the optical discs having dif

Aug. 9,

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

ferent

Oct 22, 1990

(JP)

Mar. 11, 1991

(JP) ........................................... .. 3-044798

(51)

2'285006

Int- CTG11B 7/00

Substrate thicknesses~

Instead of an Optical head hav

ing objective lenses, an optical head having a Waveguide and a plurality of Converging grating Couplers Whose aberrations

have respectively been corrected for a plurality of disc sub strates of different thicknesses is provided to achieve the

(2006-01) _

same object] An optical recording/reproducing apparatus

(52)

US. Cl. ............................. .. 369/4412, 36'9/11224, 369/4423’ 369/532

_

for recording] reproducing Or erasing an information Signal onto/from an optical disc having at least a transparent sub

(58)

Field Of Classi?cation Search ............. .. 369/4412,

Slrale and on information layer by converging a light?ux 011

369/4424, 44.23, 112.24, 53.2, 44-11, 93, 369/94, 95, 44.37; 250/2015, 227.11 See application ?le for complete search history,

the information layer through the transparent substrate. The apparatus includes optical converging devices, with di?'erent numerical apertures, focal distances or working distances, such as objective lenses or grating lenses, for performing

(56)

References Cited

aberration correction over a plurality of transparent sub

U-S- PATENT DOCUMENTS

strates of di?erent thicknesses of optical discs and a device for discriminating the type ofoptical disc based on the thick nesses of the transparent substrates. One of the optical con

4’037’929 A

7/1977 Bncot et 31'

verging devices that generates the least aberration is used

(Continued)

according to a result ofthe discrimination ofthe thickness of

FOREIGN PATENT DOCUMENTS

the optical disc loaded in the apparatus to cause the infor mation signal to be suitably recorded, reproduced or erased

onto/from the optical discs having the di?'erent substrate EP

0097250 A2

l/l984

[kl-61mm“

(Continued)

ACTUATOR DRIVING

CURRENTS FROM TRACKING CONTROL CIRCUIT II AND FDCUSING CONTROL CIRCUIT I3

14 Claims, 18 Drawing Sheets

I"

ORIVING CURRENT FROM

21TH

SELECTOR 2|

, R’

Ski-W 333’7 4g:~3835 -ill-45 I - 47 PI'DTO DETECTION SIGNAL TO

IST SELECTOR IO

1,

I '

EIIIAMbTTImENT SELECTOR 2|

43 I\*4| I q~~3o

48

——--PHOTO DETECTION SIGNAL TO IST SELECTOR

IO

US RE40,908 E Page 2

US. PATENT DOCUMENTS 4,450,553 4,841,502 4,937,808 5,091,815 5,091,901 5,097,464 5,173,816

A A A A A A A

5/1984 6/1989 6/1990 2/1992 2/1992 3/1992 12/1992

Holster et 31. Murakami et a1. Shimada et a1. Suzuki Yamamoto et a1. Nishiuchi et a1. Osihara

5,208,801 A

5/1993 Finegan

5,255,262 A

10/1993 Best et 31.

FOREIGN PATENT DOCUMENTS EP EP EP EP

144436 0252445 0327033 452953

A1 A1 A2 A3

6/1985 1/1988 8/1989 10/1991

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Sheet 2 0f 18

FIG. 2

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FIG.3B

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AMENDED

FIG.4A RECORDING WE;

{Ty FL \lDOISC suesmr: _

1 {Low NA LENS

AMENDED

FIG.4B

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OF5Z.MS0EmGU Emm_EUNJwm

mZJOk
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ZJOC
2w.0hC3m_D>%QmE

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FIG.I6 WVEVBIT OF CONVEFKED SPOT

EMITTED LIGHT

WAVEGUIDE LIGHT

OPTICAL

V

,

wAvscsuos ,

j .3 J‘

as“ mmsou =R --?Z

9,

/1V @s 7""1‘9'” 4 CONVERGING GRATING COLPLER

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Sheet 17 0f 18

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FIG l?

ZOwLrJUOZw-
V0

TRACKING ERROR SIGNAL

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Sheet 18 0f 18

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FIG. |8A PRIOR ART

0

, RECORDING LAYER

__-____-_

I __J-__

DISC SUBSTRATE

LENS

H6185

PRlOR ART

,RECORDING LAYER / _

_

_

_

_

__

--__..L__..__.__

N USC

SUBSTRATE

LENS