Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
216 words
A method of calibrating a system for the recording and readback of optically detectable data of the type which comprises a record medium (30) formed from a material which is sensitive to optical radiation, means (67) for generating a beam of light (47), means (33) for scanning said beam of light relative to the surface of said medium, means (75) for selectively varying the intensity of said beam of light so as to record data at selected positions on said surface and means (79) for reading back said recorded data, said calibrating method comprising the operation of controlling the recording intensity of said beam of light so that signals from said readback means have a maximum amplitude, characterised said operation of controlling said recording intensity comprises utilising said beam of light to record a plurality of test patterns (29) on the surface of said medium each pattern being recorded with a different intensity of said beam of light, reading back said test patterns and generating a readback test signal from each test pattern, detecting the readback test signal having the largest amplitude, and utilising the intensity of the beam of light used to record said test pattern which generates said readback test signal having the largest amplitude for said light beam when it is recording data.
Claim 2
Dependent Claim
35 words
A method as claimed in Claim 1 characterised in that said test patterns are recorded in sequence and the intensities of the beam of light used to record successive patterns vary by a preselected amount.
Claim 3
Independent Claim
24 words
A method as claimed in either of the preceding claims characterised in that said test patterns are located in different regions of said medium.
Claim 4
Dependent Claim
34 words
A method as claimed in Claim 3 characterised in that said medium is a disk and said different regions of said medium containing said test patterns radially are spaced apart radially across said disk.
Claim 5
Dependent Claim
26 words
A method as claimed in claim 4 characterised in that said different regions are selected on the basis of the amount of use for recording data.
Claim 6
Dependent Claim
221 words
Apparatus for calibrating a system for the recording and readback of optically detectable data of the type which comprises a record medium (30) formed from a material which is sensitive to optical radiation, means for generating a beam of light (47), means (33) for scanning said beam of light relative to the surface of said medium, means (75) for selectively varying the intensity of said beam of light so as to record data at selected positions on said surface and means (79) for reading back said recorded data, said calibrating apparatus comprising means for controlling the recording intensity of said beam of light so that signals from said readback means have a maximum amplitude, characterised said means for controlling said recording intensity comprises means for utilising said beam of light to record a plurality of test patterns (29) on the surface of said medium each pattern being recorded with a different intensity of said beam of light, means for reading back said test patterns and generating a readback test signal from each test pattern, means for detecting the readback test signal having the largest amplitude, and means for utilising the intensity of the beam of light used to record said test pattern which generates said readback test signal having the largest amplitude for said light beam when it is recording data.
Claim 7
Dependent Claim
34 words
Apparatus as claimed in Claim 6 characterised in that said test patterns are recorded in sequence and the intensities of the beam of light used to record successive patterns vary by a preselected amount.
Claim 8
Dependent Claim
23 words
Apparatus as claimed in Claim 6 or Claim 7 characterised in that said test patterns are located in different regions of said medium.
Claim 9
Dependent Claim
33 words
Apparatus as claimed in Claim 8 characterised in that said medium is a disk and said different regions of said medium containing said test patterns radially are spaced apart radially across said disk.
Claim 10
Dependent Claim
25 words
Apparatus as claimed in Claim 9 characterised in that said different regions are selected on the basis of the amount of use for recording data.