Optical recording/reproducing method and apparatus

Claim 2

An optical recording/reproducing apparatus for recording and reproducing data by irradiating information tracks on a recording medium with a light beam, comprising: (a) a movable optical head (2) for writing and/or reading information on and/or from said recording medium (1) by irradiation with the light beam; (b) first demodulating means (20, 23) connected to said optical head (2) for performing reproduction and demodulation of data; (c) means (11, 12) for detecting that said optical head (2) has attained a predetermined position located within said optical recording/reproducing apparatus; (d) second demodulating means (24) for decoding control parameter information recorded on said recording medium (1) but differing from said data; and (e) driving means (33, 35) connected to said optical head (2) for establishing optical conditions for recording or reproduction of said first data on the basis of the decoded control parameter information.

Claim 3

An optical recording/reproducing apparatus according to claim 1, where said second demodulating means (24) includes means (24) for detecting the level of a signal obtained through said optical head (2) with successive timing pulses by means of a program.

Claim 4

An optical recording/reproducing apparatus according to claim 2, wherein said first demodulating means (20, 23) includes third means (21) for demodulating an MFM-modulated signal and fourth means (22) for demodulating 2-to-7 modulated signal; and wherein said second demodulating means includes switch means (28) for selecting either one of said third or fourth means on the basis of information concerning the type of modulation included in said control parameter information.

Claim 5

An optical recording/reproducing apparatus according to claim 3, wherein said drive means (33, 35) includes means for setting a current to be supplied to said optical head on the basis of the value of recording power data contained in said control parameter information.

Claim 6

An optical recording/reproducing apparatus according to claim 1, wherein said detecting means (11, 12) includes a projection (11) mounted on said optical head (2) and an optical sensor (12) installed in said optical recording/reproducing apparatus for producing a signal indicating that the optical path thereof is inter­rupted by said projection (11) when said optical head (12) has attained a position where said light beams irradiates a track on said recording medium (1), said track having said control parameter information recorded thereon.

Claim 9

An optical recording/reproducing method accord­ing to claim 6, wherein the information recorded on said designated regions is phase-encoded parameter data, of which signal includes a low frequency component having a half-period of 20 to 40 micro seconds and a high frequency component having a period of 180 to 400 nano seconds, said parameter information being recorded on one informa­tion track at more than three areas, inclusive thereof, said information track being provided in a number greater than one hundred.

Claim 10

An optical recording/reproducing apparatus for recording and/or reproducing data on and/or from informa­tion tracks on a recording medium through irradiation by a light beam, comprising: (a) an optical head (2) for writing and/or reading information on and/or from said recording medium (1) by irradiating a desired track on said recording medium (1) with the light beam; (b) a plurality of demodulating circuits (23, 24) connected to said optical head and including (i) a plurality of first means (23) for demodulating said information by using a phase locked loop, and (ii) second means (24) for decoding parameter information indicating optical write and read conditions recorded on tracks in a predetermined region differing from the region on which the first mentioned information is written or recorded; (c) means (11, 12, 3, 26) for setting said optical head (2) at a predetermined position on said recording medium which corresponds to the tracks in said predeter­mined region; and (d) means (28) connected to said second means (24) for selecting one of said plural first means (23) on the basis of information concerning the type of modulation contained in said parameter information.

Claim 11

An optical recording/reproducing apparatus for recording and/or reproducing data on and/or from informa­tion tracks on a recording medium through irradiation by a light beam, comprising: (a) an optical head (2) for writing and/or reading information on and/or from said recording medium (1) by irradiating a desired track on said recording medium (1) with the light beam; (b) a plurality of demodulating circuits (23, 24) connected to said optical head and including (i) a plurality of first means (23) for demodulating said information by using a phase locked loop, and (ii) second means (24) for decoding parameter information indicating optical write and read conditions recorded on tracks in a predetermined region differing from the region on which the first mentioned information is written or recorded; (c) means (11, 12, 3, 26) for setting said optical head (2) at a predetermined position on said recording medium which corresponds to the tracks in said predeter­mined region; and (d) means (28) connected to said second means (24) for selecting one of said plural first means (23) on the basis of information concerning the type of modulation contained in said parameter information.

Claim 12

An optical recording/reproducing apparatus according to claim 8, further including laser drive means (35) capable of controlling power supplied to said optical head on the basis of information concerning recording power contained in said parameter information.