Recording/reproducing device
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsTakeshi Nakajima, Harumitsu Miyashita, Toshiya Akagi, Shinichi Konishi
Life of this patent
Estimating the term…
Abstract
A recording/producing device for writing data on a recording medium, or reading data from the recording medium, wherein data matching a recording pattern so specified as to include a plurality of mutually different sets of mark lengths and space lengths is written on the recording medium, and the data is then read to generate data signals. An edge shift detector uses data signals to measure the edge shift amount of a mark formed on a recording medium for each set of a mark length and a space length. A record controller sets a recording parameter for each set of a mark length and a space length based on the measured edge shift amount.
Claims28
A device for writing data expressed by sets of marks and spaces formed on a recording medium in said recording medium, and/or reading said data from said recording medium, comprising:
- a writing unit for writing on said recording medium predetermined data matching a recording pattern so specified as to include a plurality of contiguous, mutually different sets of mark lengths and space lengths;
- a reading unit for reading said predetermined data from said recording medium to generate a data signal matching said predetermined data;
- an edge shift detector for measuring an edge shift amount of each of said marks formed on said recording medium for each one of said sets of mark lengths and space lengths using said data signal;
- and
- a record controller for setting a recording parameter for each one of said sets of mark lengths and space lengths based on said measured edge shift amount,
- wherein said recording pattern includes all of the sets of mark lengths and space lengths, the mark lengths ranging from mT to (m+a)T and the space lengths ranging from mT to (m+b)T, a and b each being an integer of 0 or greater, and the shortest mark space and the shortest space length each being represented by mT, m being a predetermined integer of 1 or greater and T being a period of a clock signal, and
- wherein said edge shift detector measures separately an edge shift amount of a leading edge of each said mark and an edge shift amount of a trailing edge of each said mark for each of said sets of mark lengths and space lengths.
A device for writing data expressed by sets of marks and spaces formed on a recording medium, and/or reading said data from said recording medium, comprising:
- a writing unit for writing on said recording medium predetermined data matching a predetermined recording pattern so specified as to include a plurality of contiguous mutually different sets of mark lengths and space lengths;
- and
- an edge shift detector for measuring an edge shift amount of each of said marks recorded on said recording medium based on said predetermined data read from said recording medium,
- wherein said predetermined recording pattern is specified such that each of a×b×2 of the mutually different sets of mark lengths and space lengths appears once, a shortest mark length and a shortest space length being represented by mT, m being a predetermined integer of 1 or greater, and T being a period of a clock signal, a and b being any integer of 0 or greater, with mark lengths of (m+a)T, space lengths of (m+b)T and polarities determined depending on a leading edge and a trailing edge of said mark,
- said predetermined recording pattern being further specified so that said plurality of sets of mark lengths and space lengths appear with equal frequency, and a digital sum value of said predetermined recording pattern equals 0.
A recording and reproducing device for writing data expressed by sets of marks and spaces formed on a recording medium, and/or reading said data from said recording medium and for optimizing recording parameters or the marks, the recording and reproducing device including a writing unit for writing on said recording medium, predetermined data matching a recording pattern so specified so as to include a plurality of mutually different sets of mark lengths and space lengths, and a reading unit for reading said predetermined data from said recording medium to generate a data signal matching said predetermined data, said device comprising:
- an edge shift detector for measuring an edge shift amount of said mark formed on said recording medium for each of said sets of a mark lengths and a space lengths using said data signal;
- and
- a record controller for setting a recording parameter for each of said sets of a mark lengths and a space lengths based on said measured edge shift amount,
- wherein if a shortest mark length and a shortest space length are each represented by mT, m being a predetermined integer of 1 or greater, and T being a period of a clock signal,
- said recording pattern is specified to include all the sets of mark lengths of mT to (m+a)T and space lengths of mT to (m+b)T, a and b each being any integer of 0 or greater,
- said edge shift detector measuring separately the edge shift amount of the leading edge of said mark and the edge shift amount of the trailing edge of said mark for each of said sets of a mark lengths and a space lengths.
A device for being used in a recording and reproducing device for writing data expressed by sets of marks and spaces formed on a recording medium in said recording medium, and/or reading said data from said recording medium and for optimizing recording parameters or the marks, the recoding and reproducing device includes a writing unit for writing on said recording medium predetermined data matching a predetermined recording pattern so specified as to include a plurality of mutually different sets of mark lengths and space lengths, comprising:
- an edge shift detector for measuring the edge shift amount of said mark recorded on said recording medium based on said predetermined data read from said recording medium,
- wherein if a shortest mark length and a shortest space length are each represented by mT (m is a predetermined integer of 1 or greater, and T is a period of a clock signal),
- said predetermined recording pattern is so defined that a×b×2 sets (a and b are each any integer of 0 or greater) with mark lengths of m T to (m+a)T, space lengths of mT to (m+b)T and polarities determined depending on the leading edge and trailing edge of said mark each appear once, and
- said predetermined recording pattern is specified so that said sets of mark lengths and space lengths appear with equal frequency, and a digital sum value of said predetermined recording pattern equals 0.
Dependencies are inferred from the claim text.