Arrangements for using detected phase differences for setting laser power levels

Abstract

For application of asymmetry trial writing onto phasechange recording discs, this invention is intended to determine an optimum level of recording power accurately. Single pattern or random pattern signals are recorded, and phase differences between PLL clock edges and data edges are detected using reproduced signals to determine a threshold value of recording power where a predetermined percentage of phase differences occurs. The threshold power is then multiplied by a constant to provide a optimum level of recording power. Further, there are disclosed arrangements for determining an optimum power condition at a point where an error count (jitter) is minimized, and determining an optimum power condition as an averaged power level existing between low and high power conditions.

What is claimed is:  
     
         1 . A data recording apparatus determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, comprising: 
 a determination apparatus using recorded/reproduced trial marks of only a substantially same channel bit length to determine said writing condition.    
     
     
         2 . An apparatus as claimed in    claim 1   , wherein said data recording medium is more specifically an optical data recording medium, and said determination apparatus more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         3 . An apparatus as claimed in    claim 1   , wherein said trial marks are more specifically of only a substantially 11T channel bit length (where T is a predetermined length).  
     
     
         4 . An apparatus as claimed in    claim 1   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said determination apparatus more specifically uses said groups to determine said writing condition.  
     
     
         5 . An apparatus as claimed in    claim 4   , wherein said determination apparatus more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         6 . An apparatus as claimed in    claim 5   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         7 . An apparatus as claimed in    claim 5   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         8 . An apparatus as claimed in    claim 5   , wherein said determination means more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and said determination means then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         9 . An apparatus as claimed in    claim 8   , wherein said determination means more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         10 . A data recording apparatus determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks comprising: 
 a determination apparatus using recorded/reproduced trial marks periodically written using only a substantially same pit recording waveform to determine said writing condition.    
     
     
         11 . An apparatus as claimed in    claim 10   , wherein said data recording medium is more specifically an optical data recording medium, and said determination apparatus more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         12 . An apparatus as claimed in    claim 10   , wherein said trial marks are more specifically of only a substantially 11T channel bit length (where T is a predetermined length).  
     
     
         13 . An apparatus as claimed in    claim 10   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said determination apparatus more specifically uses said groups to determine said writing condition.  
     
     
         14 . An apparatus as claimed in    claim 13   , wherein said determination apparatus more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         15 . An apparatus as claimed in    claim 14   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         16 . An apparatus as claimed in    claim 14   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         17 . An apparatus as claimed in    claim 14   , wherein said determination means more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and said determination means then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         18 . An apparatus as claimed in    claim 17   , wherein said determination means more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         19 . An apparatus as claimed in    claim 10   , wherein said trial marks are more specifically written at periodic time intervals onto said recording medium.  
     
     
         20 . A data reproducing apparatus determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, comprising: 
 a determination apparatus using phase differences between recorded/reproduced trial marks and clock pulses derived from said trial marks, to determine said writing condition.    
     
     
         21 . An apparatus as claimed in    claim 20   , wherein said data recording medium is more specifically an optical data recording medium, and said determination apparatus more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         22 . An apparatus as claimed in    claim 20   , wherein said trial marks are more specifically of only a substantially 11T channel bit length (where T is a predetermined length).  
     
     
         23 . An apparatus as claimed in    claim 20   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said determination apparatus more specifically uses said groups to determine said writing condition.  
     
     
         24 . An apparatus as claimed in    claim 23   , wherein said determination apparatus more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         25 . An apparatus as claimed in    claim 24   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         26 . An apparatus as claimed in    claim 24   , wherein said determination means more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and said determination means then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         27 . An apparatus as claimed in    claim 24   , wherein said determination means more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and said determination means then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         28 . An apparatus as claimed in    claim 27   , wherein said determination means more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         29 . A data reproducing apparatus determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, comprising: 
 a determination apparatus using recorded/reproduced trial marks of only a substantially a same channel bit length, and further using phase differences between said trial marks and clock pulses derived from said trial marks, to determine said writing condition.    
     
     
         30 . A data recording method determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, said method comprising the step of: 
 using recorded/reproduced trial marks of only a substantially same channel bit length to determine said writing condition.    
     
     
         31 . An method as claimed in    claim 30   , wherein said data recording medium is more specifically an optical data recording medium, and said using step more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         32 . An method as claimed in    claim 30   , wherein said trial marks are more specifically of only a substantially 11T channel bit length (where T is a predetermined length).  
     
     
         33 . An method as claimed in    claim 30   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said using step more specifically uses said groups to determine said writing condition.  
     
     
         34 . An method as claimed in    claim 33   , wherein said using step more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         35 . An method as claimed in    claim 34   , wherein said using step more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         36 . An method as claimed in    claim 34   , wherein said using step more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         37 . An method as claimed in    claim 34   , wherein said using step more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         38 . An method as claimed in    claim 37   , wherein said using step more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         39 . A data recording method determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, said method comprising the step of: 
 using recorded/reproduced trial marks periodically written using only a substantially same pit recording waveform to determine said writing condition.    
     
     
         40 . An method as claimed in    claim 39   , wherein said data recording medium is more specifically an optical data recording medium, and said using step more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         41 . An method as claimed in    claim 39   , wherein said trial marks are more specifically of only a substantially 1T channel bit length (where T is a predetermined length).  
     
     
         42 . An method as claimed in    claim 39   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said using step more specifically uses said groups to determine said writing condition.  
     
     
         43 . An method as claimed in    claim 42   , wherein said using step more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         44 . An method as claimed in    claim 43   , wherein said using step more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         45 . An method as claimed in    claim 43   , wherein said using step more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         46 . An method as claimed in    claim 43   , wherein said using step more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         47 . An method as claimed in    claim 46   , wherein said using step more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         48 . An method as claimed in    claim 39    wherein said trial marks are more specifically written at periodic time intervals onto said recording medium.  
     
     
         49 . A data reproducing method determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, said method comprising the step of: 
 using phase differences between recorded/reproduced trial marks and clock pulses derived from said trial marks, to determine said writing condition.    
     
     
         50 . An method as claimed in    claim 49   , wherein said data recording medium is more specifically an optical data recording medium, and said using step more specifically determines a writing laser beam power level to be used for subsequent mark writing.  
     
     
         51 . An method as claimed in    claim 49   , wherein said trial marks are more specifically of only a substantially 11T channel bit length (where T is a predetermined length).  
     
     
         52 . An method as claimed in    claim 49   , wherein said data recording medium is more specifically an optical data recording medium, and said trial marks are more specifically provided in a plurality of trial mark groups, with said groups respectively being recorded at mutually different predetermined writing laser beam power levels, and wherein said using step more specifically uses said groups to determine said writing condition.  
     
     
         53 . An method as claimed in    claim 52   , wherein said using step more specifically determines and uses data concerning phase difference levels encountered within said groups to determine said writing condition.  
     
     
         54 . An method as claimed in    claim 53   , wherein said using step more specifically uses said data concerning phase difference levels to determine a threshold writing laser beam power corresponding to a lowest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then determines an optimum writing laser beam power level for subsequent mark writing by adjusting said threshold writing laser beam by a predetermined factor.  
     
     
         55 . An method as claimed in    claim 53   , wherein said using step more specifically uses said data concerning phase difference levels to determine a minimum-difference writing laser beam power level where a lowest percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial marks, and then designates said minimum-difference writing laser beam power level as an optimum writing laser beam power level for subsequent mark writing.  
     
     
         56 . An method as claimed in    claim 53   , wherein said using step more specifically uses said data concerning phase difference levels to determine both lowest and highest writing laser beam power levels corresponding to a lowest and highest said writing laser beam power level where a predetermined percentage of said trial marks at said writing laser beam power level incur at least a predetermined phase difference from a clock pulse derived from said trial mark, and then uses the lowest and highest said writing laser beam power levels in a predetermined relationship to determine an optimum writing laser beam power level for subsequent mark writing.  
     
     
         57 . An method as claimed in    claim 56   , wherein said using step more specifically performs averaging of the lowest and highest said writing laser beam power levels to determine an averaged power level as said optimum writing laser beam power level.  
     
     
         58 . A data reproducing method determining a writing condition for a loaded data recording medium as a result of recording/reproducing trial marks, said method comprising the step of: 
 a determination apparatus using recorded/reproduced trial marks of only a substantially a same channel bit length, and further using phase differences between said trial marks and clock pulses derived from said trial marks, to determine said writing condition.    
     
     
         59 . A signal recording method comprising: 
 recording data on an information storage medium;    reading data recorded on said information storage medium to obtain a reproduced signal;    detecting phase differences between said reproduced signal and a reference signal; and    determining a condition for subsequently recording data on said information storage medium according to said phase differences;    wherein said recording, reading, detecting and determining steps are performed in the stated order.    
     
     
         60 . A method as claimed in    claim 59   ; wherein: 
 said information storage medium is an optical information recording disc;    said reference signal is a clock signal generated from said reproduced signal;    said data is recorded on said optical information recording disc in predetermined groups, with respective said groups being recorded with mutually differing laser beam power levels;    said phase differences are detected with respect to each of said groups, and said phase differences are used to determine a threshold recording power where a predetermined percentage of said phase differences occurs; and    said condition is an optimum recording power determined by multiplying said threshold recording power by a predetermined constant.    
     
     
         61 . A method as claimed in    claim 59   , wherein: 
 said information storage medium is an optical information recording disc;    said reference signal is a clock signal generated from said reproduced signal;    said data is recorded on said optical information recording disc in predetermined groups, with respective said groups being recorded with mutually differing laser beam power levels;    said phase differences are detected with respect to each of said groups, and said phase differences are used to determine a minimum-difference recording power where a minimum of said phase differences occurs; and    said condition is an optimum recording power determined by setting said minimum-difference recording power as said optimum recording power.    
     
     
         62 . Information apparatus comprising: 
 a means for recording data on an information storage medium;    a means for reading data recorded on said information storage medium to obtain a reproduced signal;    a means for detecting phase differences between said reproduced signal and a reference signal derived from said reproduced signal; and    a means for setting a condition for recording data on said information storage medium according to said phase differences.    
     
     
         63 . Information apparatus as claimed in    claim 62   , wherein: 
 said information storage medium is an optical information recording disc;    said reference signal is a clock signal generated from said reproduced signal;    said data is recorded on said optical information recording disc in predetermined groups, with respective said groups being recorded with mutually differing laser beam power levels;    said detecting means is arranged to detect said phase differences in said reproduced signal according to said laser beam power levels; and    said setting means determines, as said condition, an optimum level of recording power at which said phase differences are minimized.    
     
     
         64 . Information apparatus as claimed in    claim 62   , wherein: 
 said information storage medium is an optical information recording disc;    said reference signal is a clock signal generated from said reproduced signal;    said data is recorded on said optical information recording disc in predetermined groups, with respective said groups being recorded with mutually differing laser beam power levels;    said detecting means is arranged to detect said phase differences in said reproduced signal according to the differing said laser beam power levels; and    said setting means determines, as said condition, an optimum level of recording power by adjusting a threshold recording power where a predetermined percentage of said phase differences occurs, by a predetermined constant.    
     
     
         65 . Information apparatus comprising: 
 a means for recording data on an information storage medium;    a means for reading data recorded on said information storage medium to obtain a reproduced signal;    a means for generating a reference clock signal from said reproduced signal;    a means for determining a phase difference voltage according to phase differences between said reproduced signal and said reference clock signal;    a means for modulating said reproduced signal or reference clock signal according to a difference in level between a predetermined threshold voltage and said phase difference voltage;    a means for detecting said phase differences between said reproduced signal and said reference signal using an output signal from said means for modulating; and    a means for setting a condition for recording data on said information storage medium according to said phase differences.    
     
     
         66 . Information apparatus as claimed in    claim 65   , wherein: 
 said information storage medium is an optical information recording disc;    said data is recorded on said optical information recording disc in predetermined groups, with respective said groups being recorded with mutually differing laser beam power levels;    said means for detecting is arranged to detect said phase differences in said reproduced signal according to the differing said laser beam power levels; and    said means for setting determines, as said condition, an optimum level of recording power by adjusting a threshold recording power where a predetermined percentage of said phase differences occurs, by a predetermined constant.      67 . Information apparatus for recording and reproducing information on an optical information recording disc, comprising:    a means for rotating said optical information recording disc;    a means for focusing a beam from a semiconductor laser onto said optical information recording disc;    a laser drive means for modulating output of said semiconductor laser according to data to be recorded;    a means for reading data recorded on said information storage medium to obtain a reproduced signal;    a means for generating a reference clock signal from said reproduced signal;    a means for determining a phase difference voltage according to phase differences between said reproduced signal and said reference clock signal;    a means for modulating said reproduced signal or reference clock signal according to a difference in level between a predetermined threshold voltage and said phase difference voltage;    a means for detecting said phase differences between said reproduced signal and said reference signal using an output signal from said means for modulating; and    a means for setting a condition for recording data on said information storage medium according to said phase differences.    a CPU for controlling circuit operations of each of said means, wherein said data is recorded on said optical information recording disc and said phase differences in said reproduced signal of recorded data is detected and used to determine, as said condition, an optimum level of said laser output.