Optical storage systems with flying optical heads for near-field recording and reading

An optical storage device, comprising:

• a fixed optics module mounted on a support structure, said fixed optics module having a first lens on a first lens mount affixed to said support structure at a first point, a second lens on a second lens mount affixed to said support structure at a second point, and a third lens on a third lens mount affixed to said support structure at a third point, said lenses sequentially positioned from a light source along a first optic axis with predetermined distances with respect to one another, wherein optical materials for said lenses, said first, second and third points, materials for said lens mounts and said support structure are chosen with respect to an optical parameter of said fixed optics module such that thermal-effected movements of said support structure, said first, second and third lenses and lens cells compensate for a thermal change in said optical parameter of said fixed optics module to be within a predetermined acceptable tolerance range over a temperature range of from about 0° C. to about 75° C.;
• and
• a near-field optical head comprising a fourth lens and a fifth lens spaced from each other, said optical head disposed relative to said fixed optics module to optically communicate with said fixed optics module, wherein optical materials and lens dimensions of said fourth and fifth lenses and a mounting of said fourth and fifth lenses are chosen so that a relative spacing between said fourth and fifth lenses changes within a prespecified defocus tolerance over said predetermined temperature range.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a linear actuator having an actuator arm movable along a linear axis and an actuator unit to control the movement and position of said actuator arm;
• an optics module mounted to said actuator arm and configured to include a radiation source, a detection unit having a data detector and a servo detector, a relay lens, a steerable beam shifter, an imaging lens, and a reflector that are positioned and fixed relative to one another to couple radiation energy to and from said reflector;
• a flexure engaged to said actuator arm;
• an optical head fixed to said flexure and positioned relative to said reflector in a way to allow said reflector to guide radiation to and receive radiation from said optical head;
• and
• a medium holder configured to hold the optical storage medium and disposed relative to said linear actuator to allow said actuator arm to position said optical head over the optical storage medium by a spacing less than one wavelength of radiation so that radiation is coupled between said optical head and said optical storage medium at least in part by evanescent fields.

An optical storage device, comprising:

• a fixed optics module mounted on a support structure, said fixed optics module having a collimating lens on a first lens mount affixed to said support structure at a first point, a relay lens on a second lens mount affixed to said support structure at a second point, and an imaging lens on a third lens mount affixed to said support structure at a third point, each of said lenses sequentially positioned from a light source along a first optic axis with predetermined distances with respect to one another;
• and
• an optical head comprising an objective lens and a near-field lens spaced from each other, said optical head disposed relative to said fixed optics module to optically communicate with said fixed optics module;
• and
• a medium holder configured to hold an optical storage medium and operable to hold the optical storage medium away from the near-field lens of the optical head by a distance less than one wavelength of light from the light source so that light is coupled between the optical head and the optical storage medium by at least evanescent waves,
• wherein optical materials and lens dimensions of said lenses, the locations of said first, second and third points, and materials for said lens mounts and said support structure are chosen in a relation with respect to an optical parameter such that thermally induced movements of said support structure, said lenses and lens cells compensate for a thermal change in an optical parameter of said fixed optics module to within a predetermined tolerance range over a temperature range of from about 0° C. to about 75° C.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• an objective lens disposed to receive an input radiation beam at a selected wavelength;
• a slider having a first surface, a second surface opposing said first surface, and a radiation-transmitting path connecting said first surface and second surface, wherein said objective lens is engaged to said slider at a first fixed position near or at said first surface in said radiation-transmitting path;
• a solid immersion lens engaged to said slider at a second fixed position near or at said second surface in said radiation-transmitting path so that said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing without a servo control, said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• a medium holder disposed relative to said second surface of said slider and configured to hold the optical storage medium, wherein said medium holder is positioned in such a way that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than said selected wavelength to effect evanescent coupling between said solid immersion lens and said optical storage medium.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a radiation-coupling element formed of a transparent material having a first surface engaged to said objective lens and a second opposing surface and operable to couple radiation energy at a selected wavelength between said first and second surfaces, wherein said radiation-coupling element has an index of refraction that decreases radially from a central region to a peripheral region to effect an objective lens;
• a solid immersion lens engaged to said radiation-coupling element at said second surface and configured to have a partial spherical surface facing said first surface of said radiation-coupling element and a substantially flat portion opposing said partial spherical surface;
• and
• a medium holder disposed relative to said second surface of said radiation-coupling element and configured to hold the optical storage medium, wherein said medium holder is positioned in such a way that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than said selected wavelength to effect evanescent coupling between said solid immersion lens and said optical storage medium.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a medium holder configured to hold the optical storage medium,
• an optical head configured to have first and second optical surfaces and operable to couple radiation energy between said first and second optical surfaces, said optical head positioned relative to said medium holder in such a way that said first optical surface is spaced from said optical storage medium by a distance less than one wavelength of radiation energy to effect evanescent coupling between said optical head and said optical storage medium, wherein said optical head includes an objective lens disposed at or near said second optical surface and having a front focal point located on one side of said second optical surface opposite to said first optical surface;
• a beam shifter positioned relative to said optical head and configured to direct radiation from a first optical path along a second optical path that is substantially parallel to and is displaced from said first optical path;
• and
• an imaging lens positioned relative to said beam shifter and said optical head and configured to direct radiation from said second optical path along a third optical path which passes near said front focal point of the objective lens, wherein said third optical path and said first optical path diverge at an angle based on a distance separating said first and second optical paths.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a rotary actuator including a rotary arm;
• a radiation source mounted to the actuator arm and configured to generate radiation beam that propagates along a first path;
• a beam shifter mounted to said rotary arm and configured to direct the radiation from the first path along a second path substantially parallel to and displaced from the first path;
• an optical head mounted to a supporting element which is engaged to said rotary arm and configured to have an objective lens having a front focal point and an optical interface displaced from and located on one side of said objective lens opposing said front focal point;
• an imaging lens mounted to said rotary arm and configured to direct the radiation beam from the second path along a third path which passes near the front focal point of said objective lens, wherein the third path and the first path diverge at an angle based on a distance separating the first and second paths;
• a relay lens mounted to said rotary arm configured to collimate the beam along the first path;
• and
• a medium holder configured to hold the optical storage medium and positioned relative to said rotary actuator, wherein said rotary actuator is configured to place said optical head over said optical medium in such a way that said first optical interface is spaced from said optical storage medium by a distance less than one wavelength of radiation energy to effect evanescent coupling between said optical head and said optical storage medium.

A method for directing a beam of radiation to an optical storage medium for data retrieval and recording by using a system having an optical head with an objective lens, comprising:

• generating a beam of radiation along a first path;
• directing the beam along a second path substantially parallel to and displaced from the first path;
• and
• directing the beam from the second path along a third path which passes near the front focal point of the objective lens located near the surface of the optical storage medium, wherein the third path and the first path diverge at an angle based on the distance separating the first and second paths;
• and
• placing the optical head over the optical storage medium at a desired position by a distance less than one wavelength of radiation so as to couple at least a portion of radiation energy to and from the optical storage medium by evanescent waves.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium with passive thermal compensation, comprising:

• a fixed optical module configured to produce a radiation beam that is guided to the optical storage medium and to detect reflected radiation from the optical storage medium, said fixed optical module including:
• a first lens having a first set of properties;
• a first lens cell for holding the lens;
• a first base plate, the first lens cell being attached to the first base plate by a first base material;
• a second lens having a second set of properties;
• a second lens cell for holding the second lens;
• and
• a second base plate fixed at a predetermined distance from the first base plate, the second lens cell being attached to the second base plate by a second base material;
• an optical head positioned relative to said fixed optical module and operable to produce a lensing effect and to provide radiation coupling between the optical storage medium and said fixed optical module;
• and
• a medium holder configured to hold the optical storage medium and to place said optical head over said optical medium in such a way that said optical head is spaced from said optical storage medium by a distance less than one wavelength of radiation to effect evanescent coupling between said optical head and said optical storage medium,
• wherein the first and second set of properties, the distance between the first and second base plates, the material of the first and second base plates, the material of the first and second lens cells, and the material of the first and second lenses are chosen such that the relative positioning between the first and second lenses with respect to each other remains constant or changes within a tolerance range of the optical system under a specified operating temperature range without an active thermal control loop.

A method for configuring a near-field optical storage system and implementing passive thermal compensation, comprising:

• providing a first lens having a first set of properties;
• providing a first lens cell for holding the lens;
• attaching the first lens cell to a first base plate by a first base material;
• providing a second lens having a second set of properties;
• providing a second lens cell for holding the second lens;
• attaching the second lens cell to a second base plate by a second base material;
• positioning the second base plate at a predetermined distance from the first base plate;
• choosing the first and second set of properties, the distance, the material of the first and second base plates, the material of the first and second lenses, the base materials and the material of the first and second lens cells to maintain the relative position of the first and second lenses with respect to each other for a predetermined tolerance within a predetermined temperature range without an active temperature control loop;
• and
• guiding radiation energy through said first and second lenses to and from an optical storage medium;
• at least in part coupling radiation energy to and from the optical storage medium by evanescent waves.

A near-field optical storage system with passive thermal compensation, comprising:

• a lens base made of a base material having a prespecified coefficient of thermal expansion;
• a first lens of a first material with a prespecified first lens dimension, a prespecified first temperature dependence of refractive index, and a first lens coefficient of thermal expansion;
• a first lens cell, made of a lens cell material, affixed to said lens base at least a first point, said first lens cell supporting said first lens;
• a second lens cell mounted on said lens base and affixed thereto at least a second point, said second lens cell holding a second lens made of a second lens material with a prespecified second lens dimension and a second lens coefficient of thermal expansion, said second lens cell located a prespecified distance from said first lens cell;
• and
• a laser disposed relative to said first and second lenses, said laser having a known temperature dependence of the laser wavelength,
• wherein said coefficient of thermal expansion, said first and second lens materials, said first and second lens cell materials, the location of said second point, the distances of said first point from said first lens cell, said second point from said second lens cell, and said first lens cell from said second lens cell, a dispersion property of said first and second lenses, and said prespecified first and second lens dimensions are chosen such that thermal expansion of said lens base, said first and second lenses, and said first and second lens cells, and a change in a focus of said laser beam caused by a thermally-induced wavelength shift of the laser over a prespecified temperature range, compensate for a thermal change in an optical parameter of said optical system to within a predetermined tolerance range over a temperature range of from about 0° C. to about 75° C.

An optical storage device, comprising:

• a fixed optics module mounted on a support structure, said fixed optics module having a collimating lens on a first lens mount affixed to said support structure at a first point, a relay lens on a second lens mount affixed to said support structure at a second point, and an imaging lens on a third lens mount affixed to said support structure at a third point, each of said lenses sequentially positioned from a light source along a first optic axis with predetermined distances with respect to one another, wherein optical materials for said lenses, the locations of said first, second and third points, and materials for said lens mounts and said support structure are chosen such that thermally induced movements of said support structure, said collimating, relay, and imaging lenses, and lens cells compensate for a thermal change in an optical parameter of said fixed optics module to within a predetermined tolerance range over a temperature range of from about 0° C. to about 75° C.;
• and
• a near-field optical head comprising an objective lens and a near-field lens spaced from each other, said optical head disposed relative to said fixed optics module to optically communicate with said fixed optics module,
• wherein optical materials and lens dimensions of said objective and near-field lens and a positioning of said objective and near-field lens are chosen so that a relative spacing between said objective and near-field lenses changes to produce a focus shift within a prespecified focus tolerance over said predetermined temperature range.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a rotary actuator having a rotary arm rotatably mounted to a hub and an actuator unit to control the movement and position of said rotary arm;
• a fixed optics module mounted to said rotary arm and configured to include a radiation source, a detection unit having a data detector and a servo detector, a relay lens, a steerable beam shifter, an imaging lens, and a reflector that are positioned and fixed relative to one another to couple radiation energy to and from said reflector;
• a flexure engaged to said rotary arm;
• an optical head fixed to said flexure and positioned relative to said reflector in a way to allow said reflector to guide radiation to and receive radiation from said optical head;
• and
• a medium holder configured to hold the optical storage medium and disposed relative to said rotary actuator to allow said rotary arm to position said optical head over the optical storage medium by a spacing less than one wavelength of radiation so that radiation is coupled between said optical head and said optical storage medium at least in part by evanescent fields.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium having two recording surfaces, comprising:

• a medium holder configured to hold the optical storage medium;
• an actuator positioned relative to said medium holder and configured to have first and second actuator arms whose positions are adjustable;
• at least one optical module mounted to said actuator to produce radiation that interacts with the optical storage medium;
• a first optical head connected to said first actuator arm so that said first actuator arm is operable to position said first optical head over a desired position on the first recording surface of the optical storage medium;
• and
• a second optical head connected to said second actuator arm so that said second actuator arm is operable to position said second optical head over a desired position on the second recording surface of the optical storage medium;
• wherein said rotary actuator is configured to place each optical head over said optical medium in such a way that each optical head is spaced from said optical storage medium by a distance less than one wavelength of radiation to allow for evanescent coupling between each optical head and the optical storage medium.

A data storage system for using radiation energy to read or write data from or to an optical storage medium having at least two recording layers spaced from each other less than one wavelength of the radiation energy, comprising:

• an actuator having a movable actuator arm;
• a movable relay lens mounted to said actuator arm;
• an imaging lens disposed relative to said relay lens on said actuator arm;
• an optical head connected to said actuator arm and disposed relative to said relay lens and said imaging lens;
• and
• a medium holder positioned relative to said actuator and configured to hold the optical storage medium so that said actuator is operable to position said optical head over the optical storage medium,
• wherein said relay lens, said imaging lens and said optical head are operable to focus the radiation energy to at least two different recording layers spaced away from said optical head by less than one wavelength and to produce an effective total numerical aperture that is greater than unity at the two different recording layers.

A data storage system for using radiation energy to read or write data from or to an optical recording medium having at least two recording layers spaced from each other less than one wavelength of the radiation energy, comprising:

• an optical imaging module configured to effect a combination lens and to have an adjustable focus;
• an optical head disposed relative to said optical imaging module to receive radiation from and transfer radiation to said imaging module;
• and
• a medium holder positioned to hold the optical storage medium relative to said optical head so that said optical head is operable to couple radiation energy to and from said optical storage medium by evanescent fields,
• wherein said relay lens, said imaging lens and said optical head are operable to shift focus between the two different recording layers spaced away from said optical head by less than one wavelength and to produce an effective total numerical aperture that is greater than unity at the two different recording layers.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• at least two lasers operating to respectively produce two beams at two different wavelengths;
• an optical head disposed relative to said lasers to receive said two beams, said optical head including an objective lens fixed at a first position to receive said two beams and a near-field fixed at a second position to receive said two beams so that said objective lens and said near-field lens are fixed relative to each other to have a predetermined constant spacing;
• and
• a medium holder so disposed relative to said optical head to hold the optical storage medium that said near-field lens is spaced from said optical storage medium by a distance less than either of said two different wavelengths,
• wherein said two beams are coupled to said optical storage medium at least in part by evanescent fields and to two different recording layers in said storage medium.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• a diode laser having an active gain medium and an output facet in said active gain medium to produce a laser beam at a selected wavelength in response to a driving current;
• a control circuit, electrically connected to said diode laser and configured to provide said driving current to said active gain medium;
• and
• a medium holder so disposed relative to said diode laser to hold the optical storage medium that said output facet of said active gain medium is spaced from said optical storage medium by a distance less than said selected wavelength,
• wherein said laser beam is reflected back to said active gain medium via said output facet to produce a modulation in said driving current which indicates information in said reflected laser beam.

An apparatus for use with an optical disk drive for directing the movement of a beam of light to a surface of an optical disk, the apparatus comprising:

• a rotary actuator arm;
• a source mounted to the actuator arm configured to generate a beam of light along a first path;
• a beam shifter mounted to the actuator arm configured to direct the beam from the first path along a second path substantially parallel to the first path, the first and second paths separated by a distance;
• an objective lens mounted to the actuator arm and located near the surface of the disk, the objective lens having a front focal point;
• an imaging lens mounted to the actuator arm configured to direct the beam from the second path along a third path which passes near the front focal point of the objective lens, wherein the third path and the first path diverge at an angle based on the distance separating the first and second paths;
• and
• a relay lines mounted to the actuator arm configured to collimate the beam along the first path.

A method for use with an objective lens of an optical disk drive for directing the movement of a beam of light to a surface of an optical disk, the objective lens having a front focal point, the method comprising:

• generating a beam of light along a first path;
• directing the beam from the source along a second path substantially parallel to the first path, the first and second paths being separable by a distance;
• and
• directing the beam from the second path along a third path which passes near the front focal point of the objective lens located near the surface of the disk, wherein the third path and the first path diverge at an angle based on the distance separating the first and second paths.

An optical storage device, comprising:

• an optical head having an objective lens and a solid immersion lens, wherein said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing and said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• an optical storage medium held by a medium holder and so positioned relative to said optical head that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than one wavelength of radiation to effect evanescent coupling between said solid immersion lens and the optical storage medium,
• wherein said optical storage medium includes:
• a substrate;
• a reflector layer formed on said substrate and configured to be reflective to said radiation;
• a first dielectric layer formed on said reflector layer and substantially transparent to said radiation;
• a storage medium layer formed on said first dielectric layer and configured to interact with said radiation to either superimpose data onto said radiation or receive data from said radiation;
• and
• a second dielectric layer formed on said storage medium layer to receive said radiation from said optical head and substantially transparent to said radiation,
• wherein said second dielectric layer is less than one selected wavelength thick to allow for evanescent optical coupling between said storage medium layer and said optical head.

An optical storage device, comprising:

• an optical head having an objective lens and a solid immersion lens, wherein said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing and said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• an optical storage medium held by a medium holder and so positioned relative to said optical head that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than one wavelength of radiation to effect evanescent coupling between said solid immersion lens and the optical storage medium,
• wherein said optical storage medium includes:
• a substrate;
• a reflector layer formed on said substrate and configured to be reflective to said radiation;
• a first dielectric stack formed on said reflector layer and substantially transparent to said radiation;
• a storage medium layer formed on said first dielectric layer and operable to interact with said optical energy to produce a change in said storage medium layer or to change a property of said radiation;
• and
• a second dielectric stack formed on said storage medium layer and substantially transparent to said radiation, said second dielectric stack having an optical thickness less than one wavelength thick to allow for evanescent optical coupling between said storage medium layer and said optical head,
• wherein at least one of said first and second dielectric stacks includes alternating high-index and low-index dielectric layers configured to reduce a dependence of a reflected optical signal from said storage medium layer to said optical head on a variation in the distance from said optical head to said optical storage medium.

An optical storage device, comprising:

• an optical head having an objective lens and a solid immersion lens, wherein said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing and said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• an optical storage medium held by a medium holder and so positioned relative to said optical head that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than one wavelength of radiation to effect evanescent coupling between said solid immersion lens and the optical storage medium,
• wherein said optical storage medium includes:
• a substrate;
• a reflector formed on said substrate;
• a first dielectric layer of a high-index dielectric material formed on said reflector and configured to have a first optical thickness less than about three quarters of said selected wavelength;
• a storage medium layer formed on said first dielectric layer and operable to interact with said radiation to produce a change in said storage medium layer or to change a property of said radiation;
• a second dielectric layer of a low-index dielectric material formed on said storage medium layer and configured to have a second optical thickness less than about three eighths of said selected wavelength and greater than about one eighth of said selected wavelength, wherein said low-index material has an index of refraction less than an index of refraction of said high-index material;
• and
• a third dielectric layer of said high-index material formed on said second dielectric layer and configured to have a third optical thickness of less than about three quarters of said selected wavelength.

An optical storage device, comprising:

• an optical head having an objective lens and a solid immersion lens, wherein said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing and said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• an optical storage medium held by a medium holder and so positioned relative to said optical head that said flat portion of said solid immersion lens is spaced from said optical storage medium by a distance less than one wavelength of radiation to effect evanescent coupling between said solid immersion lens and the optical storage medium,
• wherein said optical storage medium includes:
• a substrate;
• a reflector formed on said substrate;
• a first dielectric layer of a high-index dielectric material formed on said reflector and configured to have a first optical thickness less than about three quarters of said selected wavelength;
• a second dielectric layer of a low-index dielectric material formed on said first dielectric layer and configured to have a second optical thickness less than about three eighths of said selected wavelength and greater than about one eighth of said selected wavelength, wherein said low-index material has an index of refraction less than an index of refraction of said high-index material;
• a storage medium layer formed on said second dielectric layer and operable to interact with said radiation to produce a change in said storage medium layer or to change a property of said radiation;
• and
• a third dielectric layer of said high-index material formed on said second storage medium layer and configured to have a third optical thickness of less than about three quarters of said selected wavelength.

An optical storage medium for storing data in a near-field optical storage system which positions an optical head from said optical storage medium by a distance less than one selected wavelength to couple optical energy at said selected wavelength to and from said optical storage medium at least in part by evanescent fields, said optical storage medium comprising:

• a substrate;
• a reflector layer formed on said substrate and configured to be reflective to said optical energy at said selected wavelength;
• a first dielectric stack formed on said reflector layer and substantially transparent to said optical energy at said selected wavelength;
• a storage medium layer formed on said first dielectric layer and operable to interact with said optical energy to produce a change in said storage medium layer or to change a property of said optical energy;
• and
• a second dielectric stack formed on said storage medium layer and substantially transparent to said optical energy at said selected wavelength, said second dielectric stack having an optical thickness less than one selected wavelength thick to allow for evanescent optical coupling between said storage medium layer and said optical head,
• wherein at least one of said first and second dielectric stacks includes alternating high-index and low-index dielectric layers configured to reduce a dependence of a reflected optical signal from said storage medium layer to said optical head on a variation in the distance from said optical head to said optical storage medium.

An optical storage device, comprising:

• an optical head having an objective lens and a solid immersion lens, wherein said objective lens and said solid immersion lens are fixed relative to each other to have a predetermined constant spacing and said solid immersion lens having a partial spherical surface facing said objective lens and a substantially flat portion opposing said partial spherical surface;
• and
• an optical storage disk held by a medium holder and so positioned relative to said optical head that said flat portion of said solid immersion lens is spaced from said optical storage disk by a distance less than one wavelength of radiation to effect evanescent coupling between said solid immersion lens and the optical storage disk,
• wherein said optical storage disk includes a plurality of bit cells, each having a predetermined size, and boundaries of said bit cells forming a plurality of lines which extend radially but continuously from an outer portion of the disk to an inner portion of the disk.

An optical disk drive device, comprising:

• an actuator having a movable actuator arm;
• an optical head connected to said actuator arm so that said actuator arm is operable to position said optical head at a desired position;
• and
• a medium holder positioned relative to said actuator and configured to hold a disk cartridge assembly comprising:
• an enclosure;
• a recording disk mounted for rotation in the enclosure and configured to have a recording layer that is spaced from said optical head by a distance less than one wavelength to effect evanescent optical coupling;
• and
• at least two electrostatic cleaning elements positioned on an interior surface of the enclosure, the electrostatic cleaning elements having voltages of opposite polarity, the cleaning elements engaging one side of the disk at least when the disk is at rest and when the disk is rotated at a low speed, and the cleaning elements charged to a voltage magnitude less than a threshold voltage magnitude at which the cleaning elements stick to each other or to the disk.

An optical storage device, comprising:

• an actuator having a movable actuator arm;
• an optical head connected to said actuator arm so that said actuator arm is operable to position said optical head at a desired position;
• and
• a medium holder positioned relative to said actuator and configured to hold a disk cartridge assembly comprising:
• an enclosure;
• a recording disk mounted for rotation in the enclosure and configured to have a recording layer that is spaced from said optical head by a distance less than one wavelength to effect evanescent optical coupling;
• an electronic element attached to said enclosure having updatable information indicative of contents of data in said disk;
• a display located in said enclosure operable to display said updatable information;
• and
• a user control for controlling which portion of said information is displayed on said display.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• at least two lasers operating to respectively produce two beams at a common wavelength;
• an optical head disposed relative to said lasers to receive said two beams, said optical head including an objective lens fixed at a first position to receive said two beams and a near-field fixed at a second position to receive said two beams so that said objective lens and said near-field lens are fixed relative to each other to have a predetermined constant spacing;
• and
• a medium holder so disposed relative to said optical head to hold the optical storage medium that said near-field lens is spaced from said optical storage medium by a distance less than said common wavelength,
• wherein said two beams are coupled to said optical storage medium at least in part by evanescent fields and to two different locations in a common recording layer in said storage medium.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• at least two lasers operating to respectively produce two beams;
• an optical head disposed relative to said lasers to receive said two beams and configured to include at least two near-field lenses that respectively receive said two beams;
• and
• a medium holder so disposed relative to said optical head to hold the optical storage medium that said two near-field lenses are spaced from the optical storage medium by a distance less than said common wavelength,
• wherein said two beams are coupled to said optical storage medium at least in part by evanescent fields and to two different locations in the optical storage medium.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• an actuator having at least one movable actuator arm;
• a plurality of optical heads connected to said actuator arm so that said actuator arm is operable to position said optical heads;
• and
• a medium holder positioned relative to said actuator and configured to hold an optical storage disk so that each optical head is spaced from the optical storage disk by a distance less than one wavelength of radiation from each head and that said optical heads are positioned to respectfully access different locations of said optical storage disk at least in part via evanescent coupling.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• an actuator having a plurality of movable actuator arms;
• a plurality of optical heads respectively connected to said actuator arms so that each actuator arm is operable to position a respective optical head;
• and
• a disk holder positioned relative to said actuator and configured to have a spindle which holds a plurality of optical storage disks in parallel to one another so that each actuator arm is positioned to access one disk and to place a respective optical head from the disk by a distance less than one wavelength of radiation.

An optical storage device for using radiation to write data to or retrieve data from an optical storage medium, comprising:

• an actuator having a movable actuator arm;
• an optical head connected to said actuator arm by a suspension arm so that said actuator arm is operable to position said optical head;
• and
• a medium holder positioned relative to said actuator and configured to hold the optical storage medium so that said optical head is suspended over the optical storage medium by a distance less than one wavelength of radiation,
• wherein said optical head includes a light source for producing light, at least one light detector for detecting light received from the optical storage medium, and a near-field lens for coupling light to and from the optical storage medium.

An optical storage device, comprising:

• an actuator having a movable actuator arm;
• an optical head connected to said actuator arm by a suspension arm so that said actuator arm is operable to position said optical head, wherein said optical head includes a diode laser having an output facet that outputs a laser beam and a beam masking element formed on said output facet to spatially confine said laser beam;
• and
• a medium holder positioned relative to said actuator and configured to hold the optical storage medium so that said optical head is suspended over the optical storage medium,
• wherein said output facet of said diode laser is spaced from the storage medium by a distance less than one wavelength of said laser beam and couples light to and from the storage medium without a lens.