Method of and apparatus for correcting edge interval of pit in optical recording/read-out apparatus

Claim 1

A method of correcting a pit edge interval in an optical recording/read-out apparatus comprising the steps of: (a) setting a first laser power, recording a predetermined pattern B including a plurality of different patterns An (n = 1, 2, ..., N) each having a predetermined number of rising edges and a predetermined number of falling edges, and reading out said pattern B (81, 82); (b) memorizing, based on a read-out signal of said pattern B, relationships between said patterns An and edge shift quantities thereof in a form of a table (82); (c) setting said laser power to a plurality of different values, recording a plurality of mutually different patterns Cn (n = 1, 2, ..., M) by each said laser power thus set, and reading out said patterns Cn (83); (d) obtaining, based on a read-out signal of each said pattern Cn, an edge shift quantity with respect to a unitary variation quantity of said laser power (83); (e) setting said laser power to said first laser power (83); (f) attaining, for each said pattern Cn, an edge shift quantity with respect to a unitary variation quantity of a disk recording medium surface temperature (an ambient temperature) of an optical disk (84); (g) recording said patterns Cn before recording actual data, reading out said patterns Cn, and checking to determine whether or not an edge shift beyond an allowable range occurs (90); (h) separately detecting, when said check results in an occurrence of an edge shift beyond an allowable range, a variation quantity of said laser power and a variation quantity of said recording medium surface temperature based on a quantity of said edge shift occurred, said edge shift quantity with respect to the unitary variation quantity of said laser power, and said edge shift quantity with respect to the unitary variation quantity of said disk recording medium surface temperature (91); (i) updating, based on each said variation quantity, the setting value of said laser power (93) and data of said table (94); and (j) referencing, when recording actual data, said table and for correcting the edge interval of the actual data (84).

Claim 6

A method of correcting a pit edge interval in an optical recording/read-out apparatus comprising the steps of: (a) recording a plurality of mutually different patterns Cn (n = 1, 2, ..., M) with a predetermined laser power while changing a recording medium surface temperature (an ambient temperature of an optical disk) (83); (b) recording, in a predetermined area of the optical disk, relationships between edge shift quantities of said patterns and variation quantities of said recording medium surface temperature (82); (c) reading said relationships from said optical disk and storing said relationships in a memory (84); (d) recording said patterns Cn with a plurality of laser power, reading out said patterns Cn, and attaining, based on a read-out signal, relationships between the edge shift quantities of said patterns Cn and variation quantities of said laser power (83); (e) recording, before writing actual data, said patterns Cn again, reading out said patterns Cn, and checking a read-out signal to determine whether or not an edge shift occurs therein (90); (f) obtaining, when said check results in an occurrence of an edge shift beyond an allowable range, the variation quantity of said recording medium surface temperature and the variation quantity of said laser power based on said edge shift quantity occurred, relationships between the variation quantities of said recording medium surface temperature and the edge shift quantities of said patterns Cn, and relationships between the variation quantities of said laser power and the edge shift quantities of said patterns Cn (91); and setting, based on each said variation quantity, said laser power and a correction quantity of the pit edge interval to optimal values, respectively (93, 94).

Claim 10

An apparatus for correcting a pit edge interval in an optical recording/read-out apparatus comprising: (1) recording control means (16, 12) for recording a signal on an optical disk with a laser power set for the recording; (2) first control means (82) for recording a predetermined pattern B including a plurality of different patterns An (n = 1, 2, ..., N) each having a predetermined number of rising edges and a predetermined number of falling edges and reading out said pattern B; (3) storing means (82, 13, 17, 18, 19) for memorizing therein, based on a read-out signal of said pattern B, relationships between said patterns An and edge shift quantities thereof in a form of a table (82); (4) second control means (83, 16, 12) for recording a plurality of mutually different patterns Cn (n = 1, 2, ..., M) with laser power set to a plurality of different values and reading out said patterns Cn; (5) means (83, 22) for obtaining, based on a read-out signal of each said pattern Cn, an edge shift quantity with respect to a unitary variation quantity of said laser power; (6) means (84, 22) for attaining, for each said pattern Cn, an edge shift quantity with respect to a unitary variation quantity of a disk recording medium surface temperature (an ambient temperature) of an optical disk; (7) means (90, 22) for recording said patterns Cn before recording actual data, reading out said patterns Cn and checking to determine whether or not an edge shift beyond an allowable range occurs; (8) means (91, 22) for separately detecting, when said check results in an occurrence of an edge shift beyond an allowable range, a variation quantity of said laser power and a variation quantity of said recording medium surface temperature based on a quantity of said edge shift occurred, said edge shift quantity with respect to the unitary variation quantity of said laser power, and said edge shift quantity with respect to the unitary variation quantity of said disk recording medium surface temperature; (9) third means (22) for updating, based on each said variation quantity, the setting value of said laser power (12, 16, 93) and data of said table (94); and (10) means (89, 19, Fig. 16B) for referencing, when recording actual data, said table and for correcting the edge interval of the actual data.