Patent Application
20070053276
Optical disk writing devices, such as compact disk (CD) drives, digital versatile disk (DVD) drives, and the like, may be used not only to write data, but also to inscribe visible text or graphics on a surface of a disk. This ability has made the process of labeling disks easier for many users than the previous process of generating a paper label and adhering it to the non-data surface of the disk, or handwriting on the surface of the disk with a permanent marker. However, the process generally requires user intervention to manually flip the disk over to inscribe the visible text or graphics on the non-data side. That is, one method available is to eject the disk from the drive, manually remove the disk from its holder, flip the disk over, and replace it in the drive so that the laser is positioned for burning the label information on the non-data surface of the disk. In similar fashion, a process for manually flipping the disk is often necessary when using an optical drive to read or write data on a double-sided optical disk; that is, an optical disk having data storage capability on both sides.
Complex mechanisms have been developed for automatically flipping optical disks, thereby relieving a human user of an inconvenient and time-consuming task. Such mechanisms may, for example, resemble the cumbersome flipping mechanisms of conventional jukeboxes for playing double-sided vinyl records. In some approaches to the problem, motorized mechanisms have been developed for moving an optical pickup unit (OPU) from one side of the disk to the other substantially along a U-shaped track.
Another solution for using both sides of an optical disk is to use two optical pickup units, positioning one on each side of the disk, so as to avoid having to flip the disk. The addition of a second OPU, however, adds cost and complexity.
The accompanying drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. Rather, the accompanying drawings are included to provide a further understanding of the invention.
Reading and writing to both surfaces of a medium such as an optical disk, without the manual step of flipping over the disk, may be accomplished by introducing a plurality of mirrors (such as a moveable mirror as well as a series of static mirrors), to deflect the optical beam from the bottom side to the top surface of the disk. Components of the system, in some embodiments of this invention, may be housed, if desired, in a case that is the same size as that of a standard data storage device.
Example of Data Storage Drive
Referring to the drawings, in which like reference numerals indicate like elements,
More specifically, in an illustrative embodiment, the device 100 is a data storage device for writing to, and in some embodiments reading from, an optically writable first side 111 of an optical disk 110. The data storage device 100 includes an optical pickup unit (OPU) 120 able to mark the first side 111 with an optical beam 125 such as a laser beam. The OPU 120 comprises a beam source 121 and, in some embodiments, an objective lens (not shown) for focusing the optical beam 125 onto the first side 111. The optical disk 110 also has a second side 112 opposite the first side 111. Embodiments of the invention permit the optical beam 125 to be focused onto the second side 112 of the optical disk 110.
The first side 111 of the disk 110 is the substantially planar surface of the disk 110 generally closest to the OPU 120, and the second side 112 is the opposite substantially planar surface of the disk 110. In some embodiments, one side of the disk 110 is adapted for receiving human-visible label information; such a side may be referred to as a “label side” or “non-data side” of the disk 110. In a typical embodiment, when the disk 110 is inserted in the drive 100, the disk 110 is oriented so that the label side of the disk 110 is the second side 112.
The device 100 also includes a spindle 130A, a spindle motor 130B, and a rotary encoder 130C, which are collectively referred to as the spindle motor mechanism 130. In some embodiments, spindle 130A includes or is connected to a platen (not shown) for gripping the disk 110. The device 100 further includes a sled 140A, a sled motor 140B, a linear encoder 140C, and one or more rails 140D, which are collectively referred to as the sled motor mechanism 140. Finally, the device 100 includes a controller 150.
The spindle motor mechanism 130 rotates the disk 110. In particular, the disk 110 may be situated on the spindle 130A, which is rotated or moved by the spindle motor 130B to a given position specified by the rotary encoder 130C communicatively coupled to the spindle motor 130B. The sled motor mechanism 140 moves the OPU 120 substantially radially relative to the disk 110. In particular, the OPU 120 is situated on the sled 140A, which is moved on the rails 140D by the sled motor 140B to a given position specified by the linear encoder 140C communicatively coupled to the sled motor 140B. The rotary encoder 130C and the linear encoder 140C may include hardware, software, or a combination of hardware and software.
The controller 150 controls the spindle motor mechanism 206 and the sled motor mechanism 140. By controlling the motor mechanisms 130, 140, the controller 150 is able to advance the OPU 120 to desired positions on tracks of the disk 110 (such as one or more spiral or concentric tracks). The controller 150 similarly is able to cause the OPU 120 to pass over the tracks, and to advance the OPU 120 from one track to another track. The device 100 may comprise firmware or other computer-readable media for storing instructions to the controller 150.
As will be appreciated by those of ordinary skill in the art, the components depicted in the device 100 are representative of an illustrative embodiment of the invention, and do not limit all embodiments of the invention.
A steering mechanism 220 may comprise a mechanism mover such as a motor, stepper motor, solenoid, magnetic catch, or the like, controlled by controller 150. The steering mechanism 220 allows an objective lens 230, if used, to be rotated or moved into and out of the path of the beam 125, and allows movable reflector 210A to be rotated or moved into and out of the path of the beam 125. In some embodiments, the steering mechanism 220 and objective lens 230 may be included in or connected to the OPU 120, or may be attached to or situated upon sled 140A.
In an exemplary embodiment, the steering mechanism 220 is able to rotate a supporting arm 225, such as around an axis substantially alongside (in general “substantially alongside” will be substantially parallel to) the axis around which disk 110 rotates. The steering mechanism 220 may be controlled by controller 150. A first end of the supporting arm 225 supports the objective lens 230, and a second end of the supporting arm 225 supports the reflector 210A. In a further embodiment, a first supporting arm 225 supports the objective lens 230, and a second supporting arm 225 supports the reflector 210A. Reflectors 210 are arranged such that, when reflector 210A is in the path of the beam 125, the substantially collimated beam 125 converges at a focal point on the surface of second side 112 of the disk 110.
A substantially opaque annulus 250 of the disk 110 includes the portion of the disk 110 outside of the hub 240 and outside of the non-opaque annulus 245. The substantially opaque annulus 250 may extend in some embodiments to the outer circumference of the disk 110; however, in further embodiments, a second non-opaque annulus (not shown) may encircle the substantially opaque annulus 250 proximate to the outer circumference of disk 110.
The reflectors 210 do not rotate together with the disk 110. Reflectors 210B, 210C, 210D may be statically mounted or positioned in relation to one another. When movable reflector 210A is positioned in the path of beam 125 suitably for reading or writing on the second side 112, movable reflector 210A is also positioned relative to the static reflectors 210B, 210C, 210D to reflect the beam 125 to the second side 112. In some embodiments, the statically positioned reflectors 210B, 210C, 210D may be mounted on a framework or case supporting or enclosing drive 110.
For writing on the first side 111, the OPU 120 typically produces a light beam 125 having a high numeric aperture, focused by the objective lens 230 a short distance away from the OPU 120, such as on the surface of first side 111. However, in order to use the beam 125 for reading or writing on the second side 112, it is generally desirable to replace, modify, or supplement the objective lens 230 so that the beam 125 is collimated or lensed such that it has a longer focal length, thereby allowing the beam 125 to be routed around to the second side 112 without suffering significant divergence.
The beam may be brought from the first side 111 to the second side 112 by a variety of means. In the exemplary embodiment, as illustrated, the reflectors 210 are at angles of about forty-five degrees to the surfaces of the first side 111 and the second side 112. When the second side 112 is to be written or read, the focusing lens 230 is moved out of the way of the beam 125, and a forty-five degree reflector 210A is moved into the path of the beam 125. Reflector 210A is generally smaller and shorter in length than reflectors 210B, 210C, 210D that may be statically positioned, such that reflector 210A may be readily maneuvered by steering mechanism 220 within the available space.
Reflector 210A directs the optical beam 125 substantially along the first side 111 of the disk 110, to reflector 210B beyond the edge of the disk 110. Reflector 210B may be a bar reflector that runs substantially along the axis of rails 140D along which sled 140A moves. Reflector 210B is mounted such that reflector 210B directs the beam 125 around the edge of disk 110, to reflector 210C. A bar reflector may be used so that as the sled 140A moves the OPU 120 substantially radially with respect to the disk 110, the beam 125 will still impinge on the reflector 210B and be routed outside the edge of disk 110.
Once the beam 125 has reached a height above the surface of second side 112 of the disk 110, the beam 125 may impinge on another bar reflector 210C, which routes the beam 125 across the surface of the second side 112. The path of beam 125 continues above the second side 112 substantially alongside the path of outgoing beam 125 between reflectors 210A and 210B, but on the opposite side of the disk 110. The beam 125 then may impinge on another bar reflector 210D that directs the beam 125 substantially toward (in general “toward” will be perpendicular to) the surface of the second side 112, and thereafter the beam 125 strikes the surface of the second side 112. The entire path length of beam 125 is generally a little more than the full diameter of the disk 110, since the path runs approximately two half disk diameters (segments of beam 125 from 210A to 210B, and from 210C to 210D) plus additional short path segments to the surfaces of the disk 110. In some embodiments, the beam 125 is able to be focused at a focal length of approximately the diameter of disk 110, so as to be focused proximate to the surface of second side 112. In further embodiments, the beam 125 is able to be focused at a focal length of at least the diameter of disk 110, so as to be focused at or proximate to the surface of second side 112.
In some embodiments, reflectors 210B, 210C, 210D (such as bar reflectors) may be statically arranged such that the position where the beam 125 strikes the surface of the second side 112 tracks the radial motion of the OPU 120 proximate to the first side 111. It may also be desirable to include means for positioning the beam 125 more precisely once the beam 125 is adjacent to the second side 112. In such embodiments, for example, a mechanical coupling may move reflector 210D, or may move an additional mirror or lens (not shown), to redirect the beam 125 as the sled 140A moves substantially along the first side 111.
In an embodiment directed to label printing (e.g., inscribing visible text or graphics) on the second side 112, there are generally relaxed spot size requirements on the second side 112. That is, it is often desirable for a spot of light where the beam 125 strikes the second side 112 for label printing to be larger (i.e., a more diffused spot) than a spot of light where the beam 125 strikes the first side 112 for reading or writing digital data (i.e., a more focused spot). Accordingly, rather than employ a second focusing lens near the surface of the second side 112, optics of the OPU 120 and objective lens 230 may be such that a focal point of the beam 125 is at the surface of the second side 112. For example, a long focal length lens may be employed in the OPU 120, so that the beam 125 can be focused before being routed outside and over the disk 110. This is possible because label inscription on the second side 112 generally requires neither high spot quality nor the small spot size that necessitates a short focal length. In an illustrative example, with a focal point 124 mm away from the source of the beam 125, the numerical aperture of the objective lens 230 may be on the order of 0.016, which would result in a spot full-width-half-max size of 29 μm for a 780 nm beam and 24 μm for a 650 nm beam, either of which works suitably well for label printing.
In other embodiments, such as for reading or writing digital data on second side 112, it may be desirable for the beam 125 being routed to the second side 112 to be collimated as it goes around the disk 110 and across the second side 112, and to be focused shortly before the beam 125 reaches the surface of the second side 112. In such embodiments, a focusing lens (not shown), such as a second objective lens 230, may be introduced into the path of beam 125, such as between reflector 210D and second side 112. In some embodiments, the second objective lens 230 may be statically positioned in the path of beam 125; however, if a minimal spot size is desired for writing digital data to the second side 112, such as for a CD or DVD data surface, then the second objective lens 230 may be actively servoed to maintain a desired focus. If the second side 112 is adapted for labeling applications, the second objective lens 230 may be placed an appropriate distance from the second side 112 in order to provide a longer focal length suitable for relaxed focusing requirements.
In a further embodiment, in order to maximize the light power of the beam 125 reaching the second side 112 surface, the optics of OPU 120 and the objective lens 230 may be designed such that truncation of the light power for spot size minimization occurs at the objective lens 230; thus, when the objective lens 230 is moved aside, more light from beam 125 may be allowed to travel to the second side 112 surface.
In the exemplary embodiment illustrated in
In the exemplary embodiment, OPU 120 includes an objective lens 230 and a beam source 121 (such as a laser) for generating beam 125. OPU 120 is connected to a steering mechanism 220, such as a rotating mechanism for rotating the OPU 120, thereby allowing the beam 125 to be directed substantially toward the first side 111 as shown in
Steering mechanism 220 is able to cause the OPU 120 to rotate ninety degrees, thereby directing the beam 125 from a path substantially toward first side 111 (as shown in
As illustrated in
Once the beam 125 has reached a height above the surface of second side 112 of the disk 110, the beam 125 impinges on another bar reflector 210C, which routes the beam 125 across the surface of the second side 112. The path of beam 125 continues above the second side 112 substantially alongside the path of outgoing beam 125 between reflectors 210A and 210B, but on the opposite side of the disk 110. The beam 125 then impinges on another bar reflector 210D that directs the beam 125 substantially toward the surface of the second side 112, and thereafter the beam 125 strikes the surface of the second side 112.
When the beam 125 is routed to the second side 112, the beam 125 should either be of long focal length or collimated; otherwise, the beam 125 will substantially diverge, which is generally not desired. In the illustrated embodiment, the objective lens 230 shown in
In the exemplary embodiment, OPU 120 includes an objective lens 230 and a beam source 121 (such as a laser) for generating beam 125. A steering mechanism 410, such as an optical motor mechanism (which may, for example, include one or more solenoids, galvanometers, or the like) is able to move a reflector 210A (e.g., arranged at forty-five degrees) out of the path of the beam 125 (shown in
When the second side 112 is to be written or read, reflector 210A directs the optical beam 125 substantially along the first side 111 of the disk 110, to impinge on reflector 210B beyond the edge of the disk 110. Reflector 210B is mounted such that reflector 210B directs the beam 125 around the edge of disk 110, to reflector 210C. A bar reflector may be used for reflector 210B so that as the sled 140A moves the OPU 120 substantially radially with respect to the disk 110, the beam 125 will still impinge on the reflector 210B and be routed around the edge of disk 110.
Once the beam 125 has reached a height above the surface of second side 112 of the disk 110, the beam 125 may impinge on another bar reflector 210C, which routes the beam 125 across the surface of the second side 112. The path of beam 125 continues above the second side 112 substantially alongside the path of outgoing beam 125 between reflectors 210A and 210B, but on the opposite side of the disk 110. The beam 125 then may impinge on another bar reflector 210D that directs the beam 125 substantially toward the surface of the second side 112, and thereafter the beam 125 strikes the surface of the second side 112.
When the beam 125 is routed to the second side 112, the beam 125 should either be of long focal length or collimated; otherwise, the beam 125 will substantially diverge, which is generally not desired. In the illustrated embodiment, the objective lens 230 shown in
Reflectors 210B, 210C, 210D may be statically positioned so as to enable the use of an optical beam 125 to write to (or read from) both the first side 111 and the second side 112 of disk 110, as more fully described with respect to
A beam source 121, such as a laser for generating the beam 125, may in some embodiments be included in the OPU 120, and in some embodiments may be separated from the OPU 120. Further embodiments may include two beam sources 121, one of which is included in the OPU 120.
As shown in
In some embodiments, the OPU 120 comprises two focusing lenses 230, 231. A first focusing lens 231 (as shown in
In some embodiments, an exemplary OPU 120 may comprise a steering mechanism 410 including a reflector 210A. The steering mechanism 410 is able to use the reflector 210A to steer the beam 125 in at least two directions. For example, reflector 210A may be a movable mirror positionable by the steering mechanism 410 (which may, for example, include one or more solenoids, galvanometers, or the like, and may be controlled by controller 150). The steering mechanism is able to position the reflector 210A to reflect the beam in a first direction for directing the beam 125 to the first side 111, or in a second direction for directing the beam 125 to the second side 112. The reflector 210A is able to reflect the beam 125 in the first direction, substantially toward the first side 111 of the disk 110, such that the beam 125 passes through focusing lens 231. The reflector 210A is also able to reflect the beam 125 in the second direction, substantially along the first side 111, such that the beam 125 passes through focusing lens 230 and impinges on reflector 210B.
In an alternate embodiment, the reflector 210A is able to reflect the beam 125 only in the second direction. In this alternate embodiment, the OPU 120 includes a second beam source 121A configured to emit a second beam (not shown) directed in the first direction, substantially toward the first side 111 of the disk 110, such that the beam 125 passes through the first focusing lens 231 having a short focal length suitable for focusing the beam 125 on the first side 111. This alternate embodiment thus has two sources for beam 125: the first beam source 121 emits a beam 125 that may be directed to strike the second side 112, and the second beam source 121A in OPU 120 emits a beam 125 that may be directed to strike the first side 111.
As shown in
Exemplary Embodiments Having Pivoting Arm
In some embodiments, the pivoting mechanism 510 is also able to move the arm 520 substantially alongside the rotational axis of the pivoting mechanism 510 (e.g., raising and lowering the arm 520) to position the arm on either side of disk 110. In the drawing, dotted lines illustrate a second position of OPU 120 and arm 520, shown as OPU 120′ and arm 520′, in which the arm 520 has been rotated to a position clear of the disk 110, such that the arm 520 may be moved in an axial direction from one side of disk 110 to the other side without touching the disk 110.
In the exemplary embodiment of
In this embodiment, OPU 120 includes an objective lens 230 and a beam source (such as a laser) for generating beam 125. The OPU 120 also includes a steering mechanism, not shown, which may comprise optics or mechanics for allowing the controller 150 to select a direction of the beam 125. For example, the beam 125 may be directed either substantially toward the first side 111, or substantially toward the reflector 210B so that a substantially collimated beam 125 is routed around the disk 110 to reflectors 210C and 210D, and thence to the surface of the second side 112.
In the exemplary embodiment of
Exemplary Methods
The method 700 begins at block 701. At block 710, a light beam 125 is generated in a first direction relative to a first side 111 of the disk 110. In some embodiments, the first direction is substantially toward the first side 111. In other embodiments, such as the fourth embodiment illustrated in
At block 720, the light beam 125 is directed in a second direction substantially along the first side 111, such that the light beam 125 is configured to impinge on a first reflector 210B.
At block 730, the light beam 125 is reflected in a third direction, such that the light beam 125 is routed outside a substantially opaque annulus 250 of the disk 110. In some embodiments, the beam 125 is routed outside an outer circumference of the disk 110, distal to the hub 240. However, the term “outside” does not require a radial distance larger than the radius of the disk 100, just one that does not coincide with the substantially opaque annulus 250. For example, in further embodiments, the beam 125 may be routed outside the substantially opaque annulus 250 by routing the beam 125 through the hub 240 or through a non-opaque annulus 245 encircling the hub 240.
At block 740, the light beam 125 is reflected in a fourth direction substantially opposite the second direction. At block 750, the light beam 125 is reflected in a fifth direction substantially toward the second side 112 of the disk 110. The second side 112 is opposite the first side 111. At block 760, the light beam 125 strikes a second side 112 of the disk 110 opposite the first side 111. The method concludes at block 799.
Although exemplary implementations of the invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
