Recording/reproducing system using phase encoding of optical storage medium

An optical data record for storing information and from which record the information can be reproduced, comprising:

• an optical storage medium having a data track formed by a plurality of sets of variably spaced apart marks, each of said sets having spacing between marks of that set for encoding first information and having variable optical phase shifting characteristics of marks of that set for encoding second information, and wherein each of said plurality of sets of marks when illuminated with coherent read light form interference light patterns emanating from said optical storage medium that have intervals between maxima and/or minima that represent said spacing and hence said first information, and relative amplitudes of said maxima and/or minima that represent said variable optical phase shifting characteristics of marks within that set, and hence said second information.

An apparatus for reproducing information from an optical storage medium having a data track formed by a plurality of sets of spaced apart marks encoding first information as variable spacing between marks of each of said sets transverse to a read light beam axis and second information as variable height, depth, optical thickness of refractive index of marks of each of said sets in a storage medium dimension substantially along the read light beam axis, comprising:

• light source means having at least one frequency of substantially coherent light in a read beam adapted to be directed at said data track for interacting with said plurality of sets of spaced apart marks to form interference light patterns emanating from said optical storage medium in which intervals between maxima and/or minima represent said variable spacing, and relative amplitudes of said maxima and/or minima represent relative phase shift effects due to said variable height, depth, optical thickness or refractive index of marks in said plurality of sets;
• and
• photosensor means for sensing interference light patterns caused by interaction of said coherent light with said plurality of sets of spaced apart marks and for producing electrical signals representing said first and second information.

A system for recording information on an optical storage medium comprising:

• recording means for storing information on an optical storage medium having a data track, said data track having a plurality of sets of spaced apart marks encoding the information as variable spacing of said spaced apart marks transverse to an optical read beam axis and as variable relative dimensions of said spaced apart marks in dimensions in line with said optical read beam axis so that said sets of spaced apart marks when illuminated with a source of read light directed along said optical read beam axis form interference light patterns emanating from said optical storage medium in which intervals between maxima and/or minima of such interference light patterns represent information encoded as said variable spacing and in which relative amplitudes of said maxima and/or minima represent information encoded as said variable relative dimensions of said spaced apart marks in line with the optical read beam axis.

A method of recording information onto and reproducing such information from an optical storage medium comprising:

• storing information on an optical storage medium in a data track having a plurality of sets of spaced apart marks, the spacing between marks of each of said sets being variable for encoding first information, and having variable relative height, depth, optical thickness or refractive index for encoding second information;
• and
• reading information stored in said data track by illuminating said data track with coherent read light that interacts with each of said plurality of sets of spaced apart marks to form interference light patterns emanating from said optical storage medium in which intervals between maxima and/or minima of said interference light patterns represent said spacing of said marks and relative amplitudes of said maxima and/or minima represent said variable relative height, depth, optical thickness or refractive index of said marks, and by photosensing said interference light patterns and converting photosensed light therefrom into electrical signals representing said first and second information.

A system for recording information onto and reproducing such information from an optical storage medium comprising:

• recording means for storing information on an optical storage medium having a data track formed by a plurality of sets of spaced apart marks, each of said sets encoding the information as variable relative height, depth, optical thickness or refractive index of said spaced apart marks within each of said sets;
• and
• reproducing means for reading information stored in said data track, including light source means that is adapted to be directed at said data track for interacting with said plurality of sets of spaced apart marks to form interference light patterns emanating from said optical storage medium in which relative amplitudes of maxima and/or minima of said interference patterns represent said variable relative height, depth, optical thickness or refractive index of the marks within each of said sets, and said reproducing means including photosensor means for sensing interference light patterns caused by each of said plurality of sets of spaced apart marks in said data track and for conveying light therefrom into electrical signals representing said information.

A system for recording information onto and reproducing such information from an optical storage medium comprising:

• recording means for storing information on an optical storage medium having a data track formed by a series of marks disposed along said data track encoding the information within said data track as variable relative height, depth, optical thickness or refractive index of the marks relative to adjacent medium lands;
• and
• reproducing means for reading information stored in said data track, including coherent light source means that is adapted to be directed at said data track for interacting with said series of marks and adjacent medium lands to form interference light patterns emanating from said optical storage medium in which relative amplitudes of maxima and/or minima of said interference light patterns represent said variable relative height, depth, optical thickness or refractive index of the marks, and said reproducing means including photosensor means for sensing said maxima and/or minima of said interference light patterns caused by said marks in said data track and for conveying light therefrom into electrical signals representing said information.

An optical data record for storing information and from which record the information can be reproduced, comprising:

• an optical storage medium having a data track formed by a series of marks disposed along said data track encoding first information as variable widths of said marks transverse to said data track and transverse to an optical read beam axis, and encoding second information as variable phase shifting characteristics in line with the optical read beam axis, and wherein said marks when illuminated with coherent read light directed along said optical read beam axis form interference light patterns emanating from said optical storage medium in which intervals between maxima and/or minima of such interference light patterns represent said variable widths of said marks and hence said first information, and relative amplitudes of said maxima and/or minima represent phase shift effects due to said variable phase shifting characteristics of said marks in line with said optical read beam axis, and hence said second information.