CN100392736C - Low profile optical head - Google Patents

Abstract

An optical head of a type useable in a optical disk reader/writer is provided. The optical head has a low profile, e.g., in a vertical direction parallel to the disk spin axis, such as less than about 5 mm preferably less than about 3 mm. Substantially all components of the optical system, including a laser source, objective lens, intervening optics and photo detector are provided in the optical head and mounted in a fixed position with respect to one another. Substantially all optical components of the optical head are moved as a unit, e.g., during tracking and/or focusing. Preferably, the optical head is fabricated using wafer scale and/or stacking technologies, e.g., stacking substantially planar components to achieve the final optical head configuration.

Description

Low profile optical head

The application is as a reference at the further part of the patented claim No. 09/457104 (acting on behalf of number of documents 4154-9) of application in this in 7 days Dec in 1999 of quoting.Cross reference: title is " removable light storage device and system (Removable Optical Storage Device and System) ", also be designated and act on behalf of document 4154-1, in No. the 09/315398th, the U.S. Patent application of on May 20th, 1999 application, and title be " may command and writeable combining medium reach the application (Combination Mastered and Writeable Medium and Use in Electronic BookInternet) in the e-book network equipment ", also be designated and act on behalf of document 4154-2-PROV, in No. the 60/140633rd, the U.S. Patent application of on June 23rd, 1999 application.

Technical field

The present invention relates to a kind ofly, more particularly, relate to the shaven head of the spatial relationship that a kind of all optical modules from the LASER Light Source to object lens all are maintained fixed basically such as the shaven head that is used for the read and write CD.

Background technology

Influence a size that key factor is this optical system of optical system (such as an optical-disc reader/write device system that typically comprises laser or other light sources, camera lens, reverberator and other assembly) design, aspect quality, volume and/or size and aspect the light size and shape (size of luminous point and quality) in arrival CD time.Although used or proposed multiple systems, but these exemplary systems also are to use enough big and/or thick and heavy optical module, resemble and focus on and/or follow the tracks of these functions and carry out, for example move object lens (when for example focusing on) with respect to laser and other light source by some assemblies that only move in this system.Do not want to be subjected to the restriction of any theory, think that the big relatively size of assembly is relevant with the luminous point size, and in fact successively by design decision, wherein, the data Layer of dish is separated with the physical surface that coils significantly, and (thereby optical path is usually by the substrate of dish or the other parts of dish before arriving data Layer, see through a segment distance of the thickness of dish typically, such as about 0.6mm or bigger.)

No matter be provided at the reason that relatively moves between optical module is what, although perhaps a kind of like this method is useful when holding bigger or thick and heavy assembly, yet also exposed some shortcomings, comprise required sizable profile key element (form factor) and with set up and safeguard light adjustment (alignment) relevant cost between these assemblies that must can relatively move to each other.This adjustment often comprises manual and/or independent adjustment or adjustment program, and these programs can increase the cost of the cost of the manufacturing of reader/writer and assembling and design, maintenance, repair or the like with being out of favour.Therefore, providing a kind of can reduce or eliminate the needs that relatively move between the optical module and/or can reduce or eliminate during the reader/writer manufacturing such as will be very useful to the bare headed mthods, systems and devices of small part adjustment program during the normal running.

Many early stage CDs and other optical memory system provide the reader/writer equipment that comprises such as the big form of the equipment that is used for being connected 12 inches (or bigger) diameter dishes.Yet along with the exploitation of optical storage techniques, increasing notice has been put into the feasible and practical system of the size that provides relatively little.To some such as the application that is used in the personal electronic equipments (PED), such as at No. the 09/315398th, U.S. Patent application described " packaged type optical storage device and system " (quoting as a reference) at this, one is used for reading and/or the equipment of writing optical disk is described as a relatively little profile key element, for example, approximately the 10.5mm height, 50mm is wide and 40mm is dark.In general, the read/write equipment of a practicality should hold many in its profile key element, relevant with it or influence the assembly of laser or beam optical parts except those, also comprise medium, cartridge (if any), medium rotary electric machine, power supply supply and/or adjusting, signal Processing, focusing, tracking or other servo electronic component.Correspondingly, become possibility, provide one to take that more optical-head apparatus, the system and method for small size can be more favourable in order to make a relatively little profile key element.Except the consideration of cumulative volume aspect, restriction that the profile key element of expectation is applied and/or the requirement of holding other reader/writer assembly make and provide optical-head apparatus, system and method with relative reduced size more favourable, such as having less vertically profiling or space requirement (" vertically " be meant a direction that is parallel to the CD turning axle) here, may be also very important although reduce the requirement (such as the size longitudinally of the axle that is parallel to the light arm and/or perpendicular to the lateral dimension of longitudinal axis) of other size aspect.Provide a low vertical profile to bother especially, this be because, at least in some optical designs, (comprise), need or advise the optical path (although the read/write light beam generally can arrive the plane at CD place normally) of a minimum as specific conjugation design.Therefore, it will be very useful as optical-head apparatus, system and method that the size that reduces vertical direction needs that energy needs reduced in size are provided, such as under the situation less than the PED of 12mm, preferably less than 5mm even preferably less than 3mm.

Many optical pickups/write device equipment comprises such as big relatively equipment, for example audio compact (CD) player in the one family stereo system is considering to lack relatively (particularly can receive AC power or other similar situation) aspect power consumption management or the power consumption planning.The result often provides an optical design at relative poor efficiency aspect the luminous energy (for example too utilizing camera lens and similar element, so that such as the non-annularity that adapts to LASER Light Source) in many such systems.By contrast, such as asking the equipment of describing in the 09/315398th and/or No. 60/140633 to focus on light weight and transportability in the patent in front, generally should under the energy consumption planning of a qualification, move (compare with big system and have only more limited heat-sinking capability).Therefore, it is very useful that optical-head apparatus, a system and method (as adapting to non-annularity and other optical characteristics) that can obtain the optical quality of needs is provided, meanwhile avoid unsuitable energy poor efficiency and/or unnecessary give birth to heat (such as, heat from undue use camera lens or other optic poor efficiency generation, and these undue uses and luminous energy that poor efficiency can accordingly need be higher, thereby need be with the laser of the higher electric power of distributing more heat).

Summary of the invention

The invention provides a kind of practicality and feasible system, wherein all component from laser or other light source to the shaven head of object lens fully as an integral body move together (such as, be used for focusing on and following the tracks of), that is, wherein relative other assembly of all optical modules of shaven head in fact all has a fixing position.

In one embodiment, shaven head is based on extensive producing method of chip.Preferably, have the silicon of the electronics that forms thereon with normal mode or similar wafer have pile up thereon or other modes locate the optical module of (position), preferably before this wafer of section, place some assemblies at least to form the optical module of shaven head.In one embodiment, ground floor reverberator/isolator (mirror/spacer) layer is positioned on the wafer, and locatees one or more layers optics at the top of isolator (usually and " chip " after the wafer slice shared ratio proportional similarly).In one embodiment, when LASER Light Source (preferably being installed on the wafer) emission laser, carry out the adjustment of the some or all optical component layer on isolator, and use emitted laser to help the location or to harmonize.

In one embodiment, the read/write light beam substantially is parallel to one that passes on the direction on plane of dish in the optical component layer.The one wherein substantial portion of light path and the parallel plane configuration of dish is provided, helps to provide relatively low vertically profiling.By providing one can use extensive wafer manufacturing and can be by piling up the system that makes such as the discrete component of isolator, optical module etc., can make up little a, high precision, in light weight, profile is little and/or spot definition is little shaven head with relatively low manufacturing cost.As used herein, " read/write " is meant and only is used to the structure of reading and is used for both structures of read and write.

On the one hand, provide a kind of shaven head that in optical-disc reader/write device, uses.This shaven head for example has little profile on the vertical direction of the turning axle that is parallel to dish, such as less than 5mm and preferably less than 3mm.The all component of optical system in fact comprises that (intervening) optics of LASER Light Source, object lens, insertion and photodetector all are provided in this shaven head and are installed in position fixed relative to one another.In fact all optical modules that should shaven head move together as a unit, such as during following the tracks of and/or focusing on.Preferably, this shaven head uses extensive wafer and/or piles up technology, makes to realize that final shaven head disposes such as piling up in fact smooth assembly.

According to a first aspect of the present invention, a kind of shaven head that is used for read/write medium in the optical read/write device that is used in is provided, comprising: light source, at initial light outgoing position output light; At least one first photodetector array is installed on the fixing position with respect to described initial light outgoing position, and described first photodetector array has the first surface at least one definition photodetector plane; Optical member unit, be installed on the fixed position with respect to described smooth outgoing position, described optical member unit has the first and second beam-shaping opticses of the light that is received in described smooth outgoing position output, described optical member unit also comprises at least one the 3rd optics, is configured to be used in reference to cause a few part and arrive described first photodetector array along a path from the light of described dieletric reflection; Described shaven head provides at least one first light path, and wherein said first light path is from described initial light outgoing position, and the described at least read/write medium of arrival.

According to a second aspect of the present invention, a kind of shaven head that is used for read/write device is provided, comprising: light source; Optics, comprise the first and second beam-shaping opticses, and be configured near small part from the light transmission of described light source to the data medium and first and second photodetector arraies that will separate to the space from the light transmission of described data medium reflection, each described photodetector array provides for along the position sensing of first light of described photodetector array and for the in fact insensitive output in position along the second vertical in fact light of described photodetector array.

According to a third aspect of the present invention, a kind of method that forms shaven head is provided, comprising: first light source is installed with respect to substrate; With respect to the fixed position of described first light source at least one photodetector array is being installed; The etching at least the first and second beam-shaping opticses in first optical member unit; With the described optical member unit of installation on the position of intercepting and capturing the light that described light source generates to small part with respect to described substrate at described first and second opticses.

Description of drawings

Fig. 1 is a kind of schematic block diagram that is coupled to the reader/writer driving arrangement of the main process equipment that can be used in combination with embodiments of the invention;

Fig. 2 is according to the light arm of embodiments of the invention and the perspective diagram of CD;

Fig. 3 is bare headed according to an embodiment of the invention skeleton view;

Fig. 4 is the top view of the shaven head of Fig. 3;

Fig. 5 is the side view of the shaven head of Fig. 3;

Fig. 6 is according to embodiments of the invention, the sectional view of a part by shaven head and the dish that adjoins;

Fig. 7 is according to the wafer of embodiments of the invention, part decomposition and the skeleton view of the isolator assemblies that part is installed;

Fig. 8 is the top view of the wafer of the part isolator assemblies that has installation;

Fig. 9 is the wafer top view partly that wafer slice generates afterwards;

Figure 10 is according to one embodiment of the present of invention, by the shaven head and the vertical cross-section diagram of a part of CD;

Figure 11 is according to embodiments of the invention, explanation light arm and the relative movably part skeleton view of shaven head;

Figure 12 is the part decomposition diagram according to the light arm of embodiments of the invention and shaven head;

Figure 13 is the part skeleton view according to the part of the light arm of the pin that has installation of embodiments of the invention;

Figure 14 is the vertical cross-section diagram according to the shaven head of embodiments of the invention;

Figure 15 according to embodiments of the invention, have a side view of the head assemblies of the lip-deep laser instrument that is installed in the optics die;

Figure 16 is according to the side view of the head assemblies of embodiments of the invention, use VCSEL;

Figure 17 is the block scheme that explanation can be used in the assembly among the different embodiment provided by the invention;

Figure 18 is the longitdinal cross-section diagram according to the shaven head of embodiments of the invention;

Figure 19 is the top view of the optical member unit (OEU) according to embodiments of the invention;

Figure 20 is the backplan according to the optical member unit of embodiments of the invention;

Figure 21 is the cross-sectional view of the optical member unit (OEU) according to embodiments of the invention;

Figure 22 is the top view according to the photodetector part of the bare headed substrate of embodiments of the invention;

Figure 23 is the side view of a part of substrate that Figure 22 of corresponding optical member unit (OEU) part is arranged according to embodiments of the invention synthetic, has the light beam of the selection of representing with cross-hauling, is used for clarification;

Figure 24 A and B are according to embodiments of the invention, are respectively applied for the figure of the focus error signal (FES) of first and second detectors focusing function on medium;

Figure 25 is according to embodiments of the invention, is used for the figure of the difference focus error signal (FES) of focusing function on medium;

Figure 26 is the side view according to the shaven head of embodiments of the invention, shows the path of the central shaft of selected light beam with arrow; And

Figure 27 is the side view according to the shaven head of embodiments of the invention, shows the path of selected light beam with arrow.

Embodiment

The present invention can be used in multiple driver or the drives structure, comprises what those were described in No. the 09/315398th, the U.S. Patent application in front.In structure shown in Figure 1, be coupled to main process equipment 114 (can be, for example music and/or video player, video camera and e-book or other text reading devices etc.) by interface 116 reader/writer driving arrangements 112 such as personal electronic equipments (PED).In the embodiment shown in fig. 1, reader/writer driving arrangement 112 keeps or holds the light medium, typically is CD 118, and it has hub 122, is used for being coupled or centering with respect to disc spins motor 124 under the control of Electric Machine Control 126.In one embodiment, medium 118 is first surface media, such as quote as a reference at this, described in the U.S. Patent application the 09/315398th.Use shaven head (such as what will describe below comprehensively) to read or write the bit on the medium 118, provide data or signal 132, be used for such as being delivered to main process equipment 114 by interface 116 to data read/write electronic unit 134.In one embodiment, that in fact shaven head 128 comprises is all, arrive at and/or control or influence the assembly or the equipment of laser or light beam from medium 118 reflections and testing process from being generated to along its entire path, and what comprise laser instrument or other light sources, lens, grating, hologram wave plate, catoptron, beam splitter and other influences light beam or the reflection that is used to control, refraction, diffraction or other optics, photodiode or other photodetector etc.Best, part or all ofly be used for controlling and/or modulated laser and/or conditioning, digitizing and/or the electronic component of handling detection signal all are included in shaven head.The information or the signal that use shaven head 128 to obtain also offer the light arm control electronic unit 138 that moves or control light arm 142, follow the tracks of and/or focus on such as being used for.Power supply or conditioner 144 provide power supply for electronic component and/or motor or execution unit.The difference configuration of driving arrangement 112 can comprise other assembly, not necessarily as shown in Figure 1, such as being used to hold and/or mechanical component, content control electronic unit, microprocessor or other processors, data storage memory equipment, data encryption/decryption electronic unit and/or other assemblies of Eject Media 118 and/or cartridge, after having understood the present invention openly, those skilled in the art will should be appreciated that.

Shaven head 128 size, quality, volume, shape and/or vertical, vertically and/or lateral dimension or requirement and/or cost be very significant for the overall ease for use and the cost of driving arrangement 112, particularly when the configuration of driving arrangement 112 is restricted to position, size, shape or the cost of other assemblies of driving arrangement 112, more particularly, actual when holding reader/writer driving arrangement 112 in being desirably in specific profile key element exactly, such as described in No. the 09/315398th, the above-mentioned U.S. Patent application.

Fig. 2 substantially or with the form of signal, illustrate according to an embodiment of the invention bare headed 128 and light arm 142 with respect to the position of medium 118 relation.In the embodiment of Fig. 2, shaven head 128 is installed on the fixing position with respect to light arm 142.As what below will describe in detail, preferably all component of shaven head 128 is positioned on the constant or fixing position with respect to another assembly, and promptly in fact any one optical module of shaven head 128 does not have relative displacement with respect to any another optical module of shaven head.On the contrary, in an illustrated embodiment, in order to realize the adjustment (that is, follow the tracks of) to data on the medium 118 and/or to focus on, whole bare headed 128 move with respect to medium 118 as a unit.

In a preferred embodiment, light path is configured to, the optical path length from the light source to object lens (following any folding measured on the light path along optical axis) is in fact greater than the distance of the data surface from object lens to the medium.In one embodiment, light source-object lens path is approximately 5 at least with the ratio of object lens-data surface path.Here " object lens " of Shi Yonging or " objective lens " refer to focus the light into the assembly of the recording surface of recording layer or medium.Although be generally conventional refracting telescope, also can comprise reflection, diffraction, hologram element.Although normally before light arrives medium along the last or final optical assembly of light path, also can comprise at " object lens " or " objective lens " of this application not being that light arrives the object of medium last optical assembly before.Optical path length from object lens to the data surface is the function of a plurality of factors, and these factors comprise the minimum safety interval (" operating distance ") between the numerical aperture of lens, the distance from the panel surface to the data surface (if existence) and shaven head and the panel surface.In one embodiment, expectation provides the optical path length from the light source to object lens greater than 2.5mm, and is more preferably greater than 4mm, better greater than 4.5mm.One embodiment of the present of invention comprise the equipment of realizing this light source-object lens path and low profile being provided, preferably such as reader/writer equipment can being contained in the profile key element of (vertically) profile less than about 10.5mm, even be less than or equal to 6mm.

In an illustrated embodiment, medium 118 is around being defined in this turning axle that is called vertical direction 214 rotations 212.The rotation 212 of dish provides the adjustment of the light beam with (continuously) circumferential position on medium 118.By having on the direction of radial component the radial position of moving shaven head 128 and provide expectation harmonize (tracking), preferably by the rotation 216 of light arm 142, so that one section arc 222 of the location definition of light beam arrival dish 118 by the intended radial range expansion of dish 118 about the Z-axis 218 of reality.In an illustrated embodiment, for ease of focusing on, whole bare headed 128 as a unit along path movement, such as by the rotation 224 of arm 142 for the transverse axis 226 of reality with vertical component.Although the diagram of Fig. 2 does not have scale, be enough to also illustrate that the whole vertical size that is used to hold assembly shown in Figure 2 will be subjected to the vertical profile of shaven head 128 or height 232 and other sizes such as the influence to the interval 234 of medium 118 etc.

Embodiment shown in Fig. 2, not only the optical module of shaven head 128 moves together, and shaven head wherein moves with light arm 142 (in fact tight coupling together).Also can provide an embodiment, although wherein Guang Tou assembly (preferably including light source and object lens at least) is immovable toward each other, shaven head can move with respect to part or overall optical arm.For example, in the embodiment of Figure 11, shaven head 128 can by movably or flexible, best flexible blade part 242 be coupled to light arm 142.Blade part 242 can comprise all or partially flexible P.e.c. (flexible circuit) equipment, promptly be used for to provide signal from shaven head 128.Can use multiple flexible circuit (flex circuit) material or equipment.

An example is to use the flexible circuit that comprises such as the substrate of the polyimide material of selling under trade mark Kapton, can be from E.I.du Pont de Nemours and Company of Wilmington, Delaware obtains, and forms or be equipped with one or more copper tracing wires or zone and/or one or more electronic packages thereon.Best, can control shaven head 128 with respect to the moving of light arm 142 with locating, such as by using voice coil loudspeaker voice coil 244 or other electromagnetism or electronic equipment, be used for moving this head towards or away from light arm 142.

Fig. 3-5 illustrates according to an embodiment of the invention bare headed 328.In an illustrated embodiment, scioptics base plate 314 is positioned at object lens 312 on the quarter wave plate 316.In certain embodiments, can provide the function of part or all of quarter wave plate by coating, and be not only an egative film.Can use multiple material, comprise that steel, glass or silicon form the lens base plate.Multiple material be can use, mica or the quartzy quarter wave plate that forms comprised.In certain embodiments, the function of quarter wave plate can provide by coating.Below quarter wave plate 316, be optical block, be referred to herein as periscope 318.At least periscope 318 is actually transparent on Wavelength of Laser, and defines reality (preferably with respect to vertical 45 degree) surface 322 as first angle of catoptron, and this will be discussed in more detail below.Preferably this 45 kilsyth basalt face 322 applies such as aluminium or reflection dye coatings with actual reflectance coating.In an illustrated embodiment, the inside light beam release surfaces 324 of periscope 318 also comprises best (with respect to vertical) 45 degree, in fact with first reflection of polarization (that is, using) light as mirror, and in fact with second polarization transmission light.The periscope module can be used various made, comprises such as fused silica or SF2 (flint glass).

Below periscope 318 optics die or " optical member unit " (OEU) 326.Using term " die (die) " is for convenience, should not limit the invention to the parallel pipe in this explanation, parallelogram or other shapes that are only illustrated.OEU 326 disposes lens, grating, hologram and/or other optical modules or equipment, will be discussed in more detail below.

OEU 326 is coupled to following daughter backplane 336 (preferably cut into slices from silicon chip or similar wafer, will be discussed in more detail below) by isolator module 332,334.In an illustrated embodiment, daughter backplane 336 is positioned on printed circuit board (PCB) 338 or the flexible circuit.

Light path has the source in laser diode 612, and this laser diode 612 for example uses laser base board 614 to install with respect to daughter backplane 336.In one embodiment, laser beam is collimation not, and is actually the discrete topology of the limited conjugate imaging of the formation system from the LASER Light Source to object lens.In this structure, light beam forms the optics configuration and is mainly used in the circular and/or astigmatism and/or provide light beam spot to adjust function partly or entirely of light is provided whole or in part.The potential advantage of finite conjugate (point-to-point imaging system) be actual dwindle to provide reduce or eliminate the astigmatism that causes by laser instrument.But circle optical lens 352a may cause sufficient astigmatism, advises that second lens or other optics 352b are used for astigmatism.Also can be placing lens or other optics on the surface of daughter backplane 336, between the lasers and mirrors module 332, such as being used to make circular or other optics purposes of light.In one embodiment, lens or similarly optics 352a, b dispose along light path, with in the installation of laser diode (and thus on beam direction) to small part correction angle degree error.

In an illustrated embodiment, laser diode is the side emission laser diode, and the horizontal laser light light beam 616 of laser diode 612 outputs is reflected into normal beam by 45 kilsyth basalt faces 618 with respect to daughter backplane 338 location, and this surface 618 preferably is included as a surface of isolator 332.In one embodiment, the part emission laser beam is reflected back (for example, from OEU 336), is used for monitoring and the output of control laser power.In one embodiment, laser instrument is red laser preferably, but, the present invention also is applicable to short wavelength laser, such as blue laser (for example, be used to luminous point size that obtains to reduce and the intensity data that increases), and still keep with the bare headed identical basic structure of in red laser, using (such as, structure has mobile in fact together, be installed in an end of light arm, form all opticses that each optical module plate has a plurality of optical modules by one or more optical module plates, and/or define the light path of most of length by glass or other solid substrate), although some details is (such as the shape or the power of lens or other opticses, pupil size etc.) may change to adapt to short-wavelength light.

As shown in figure 16, be used for light beam is changed over from horizontal light beam 616 surface 618 of normal beam, can not that side emitted laser device eliminates from this design by providing, such as vertical cavity, surface-emitting laser (VCSEL) 1612 (for example, described in No. the 09/315398th, the U.S. Patent application in front), can dispose or be positioned in fact emission on vertical direction 1614.VCSEL is because reducing or eliminating of the essence ring-type of its light beam and astigmatism also is very useful.

As shown in Figure 7, in one embodiment, daughter backplane 336 is to form in one little (section) part from a bigger silicon (or other) wafer 712 (Fig. 7), wafer is to use typical wafer fabrication to form, preferably include a plurality of other electronic packages that form part or all of driving circuit 112, such as high frequency lasers modulator, preceding amplifier, laser diode drive, photodetector and interlock circuit, power supply or control circuit, tracking or focus servo, data read/write electronic package etc.Utilize a plurality of silicon " chip " zones (will be by sawing or cutting and separating, be described below) wafer 712 that forms, use up picking up of guiding a plurality of laser diodes and base plate 714a to 714x and a plurality of isolator bar 716a, b, c that is integrated with catoptron are installed thereon such as making then with placement technique.Each isolator bar 716 comprises a plurality of 45 degree mirror surface (718a, 718b, 718c etc.).The catoptron 718 relative electronic packages thereon of laser diode 714 and isolator bar 716 are arranged on the wafer 712, so that laser coupled is arrived laser power, control or similar circuit, and the output beam that utilizes corresponding catoptron 718 actual adjustment laser instruments.In arrangement of components that will expectation behind wafer 712, with wafer such as along many lines (among Fig. 8 with dotted line 812a, b, c, shown in 814a, b, the c) section or cut.

As shown in Figure 8, preferably sawline 812abc is arranged as each chip that generates and has from (difference) left side of the isolator bar 716 that cuts and a left side and the right isolator 332,334 of right half generation.In generation result shown in Figure 9, each chip 912 is installed laser diode 714, bifurcated catoptron 618 and isolator 332,334 thereon with desired structure or adjustment, be preferably in and have enough remaining areas 914 on the chip 912, so that hold the various electronic packages that form as part wafer 712.

Although can use the equipment of multiple shape and size according to the present invention, in one embodiment, daughter backplane 336 has the length 512 of about 5mm and the lateral dimension 412 of about 1.5mm.

The optics die or optics (OE) piece 326 that are arranged on the daughter backplane 336 (and therefrom separated by isolator 332,334) can have multiple different configuration according to desired function.In the embodiment shown in fig. 3, OEU 326 comprises a plurality of beam-shaping opticses 352 and servo optics 354.In one embodiment, beam-shaping optics 352a, b are configured to (or in fact carrying out the function be similar to these) anchor ring or cylindrical lens, and laser beam is circular such as being used for making whole or in part, astigmatism etc.Best, this optics is configured to control whole lens as expectation, such as crosstalking of balance and optical efficiency.

Optics 352a, b, 354 can be lens or similar refractive optical components, grating or holography or other diffractive optical components etc.In certain embodiments, optics can form in the optics die by etching technique, comprises shape that approximate stride is provided, the lens, Fresnel lens etc. of shape, segmentation or " looking in the distance " continuously.Usually when other feasible, preferred refractive optical components is because the refractive optical components sensitivity higher relatively to wavelength.

OEU is smooth (rectangular parallel pipe) module of the reality between substrate or daughter backplane and periscope preferably.OEU disposes a plurality of opticses or assembly, and its structure, manufacturing, function and position can be inequality in different embodiment.Figure 18 illustrates an embodiment, and wherein OEU 1802 comprises the responsive optics 1804 of forward direction, servo optics 1806, beam-shaping optics 1808,1810, formative absorber coatings 1812, form reflectance coating 1814, back reflection coating 1816 and alignment mark 1912,1914 (Figure 19).

As shown in figure 18, the responsive optics 1804 of forward direction can be used to make some output laser to return 1820,1826 deflections such as the detector 1828 that is installed on silicon or the substrate 1830.The function of detector 1828 provides the indication of output laser power, such as being used for control or servo circuit to keep laser instrument 1832 needed read and write power levels.It should be appreciated by those skilled in the art the power that how to use from the signal controlling laser instrument 1832 of detector 1828.The responsive optics 1804 of forward direction can be such as the reflection holography that has or do not have the reflectance coating such as dyestuff or aluminium (such as, the holography of etched surface undulation on the upper surface of OEU 1802 shown in Figure 180).Reflection optics or the responsive optics 1804 of forward direction can be arranged in other positions, such as the bottom of periscope 1836 or the lower surface 1848 of other surfaces or OEU.Also the responsive optics 1804 of forward direction can be configured to deflect the light into the transmission hologram or the grating of the detector that is installed in substrate 1830 other positions in addition, on the upper surface 1838 that is installed in periscope 1836.Also can provide forward direction responsive optics 1804 with the form of prism, such as etched prism or mirror surface so that with light guide into be installed on the substrate 1830 or other detector 1828.

In the embodiment of Figure 18, OEU 1802 also comprises servo optics (SOE) 1806.Servo optics 1806 is used to revise from the light that coils 1842 light that return and/or will return guides one or more detector arrays 1844 into, thereby generates useful tracking signal, focus signal and/or data-signal (for example, will be discussed in more detail below).SOE 1806 can be that holographic parts maybe can be that form or etched refractive component.Although SOE 1806 shown in Figure 180 is positioned at the upper surface 1846 of OEU 1802, also SOE can be arranged on the lower surface 1848 of light piece 1802.An embodiment also can be provided, wherein be used to revise the light that returns from dish, such as two or more lens, grating, holographic parts etc. are provided more than one optics.Also can provide a plurality of embodiment, wherein with one or more SOE arrangements of components outside OEU 1802, on the surface that is arranged in periscope 1836.SOE 1806 can be such as cylinder or prismatic lens, such as the general type that uses with four detectors in so-called scattering focusing scheme.Refractive component can be by etching, compacting, machine work or stamped, and can apply or do not add coating.

Beam-shaping optics 1808,1810 can be to be arranged in such as refraction on the path of output beam and/or diffraction component, revising the angle deviating of laser beam, such as especially so that realize the beam profile of expectation at pupil 1852 places of object lens 1854.Size when laser beam arrives object lens 1854 and intensity influence in the shape of coiling focal spot on 1856 with respect to the size of object lens 1854 and the relation of shape, therefore and influence the ability of resolution data mark, and influence the total amount that track is crosstalked in track and the track.When LASER Light Source 1832 is the edge emission laser diode, as shown, the light beam of the normally oval Gaussian distribution form of initial laser beam.When light beam arrives object lens 1854, light beam will have one in fact with the tangent oval axis of dish track, another oval axis is actually the dish track radially.The circumference place of object lens 1854 radially and the laser intensity (being expressed as the number percent of central light beam intensity) on tangential be called the edge strength on these directions.Concrete design of Driver can be provided with or lower limit edge strength.In some embodiment at least, particularly under the situation that low-power drives, such as for portable set, may limit provides from the higher relatively light quantity of laser instrument arrival dish or bigger light number percent.In these cases, usually preferred lower edge strength has avoided lens to overflow in fact because this shows, has avoided luminous energy to overflow or waste thus.In one embodiment, edge strength is not higher than 80% on the tangential direction and/or is not higher than in the radial direction 40% (comparing with center or maximum intensity).In one embodiment, edge strength preferably be no less than 50% on the tangential direction and/or be no less than in the radial direction 15%.Under the restriction of lower edge strength, all utilized light has all passed through lens.Therefore, at least one embodiment, beam-shaping optics 1808,1810 is configured to help to revise light beam, to realize desired intensity (or other) requirement at lens 1854.In at least one embodiment, one or two beam-shaping lens the 1808, the 1810th, anamorphic aspherical surface parts.

Although in the embodiment of Figure 18, two optical modules 1808,1810 of output beam 1858 by on the apparent surface 1846,1848 of OEU 1802, forming, but also can provide embodiment, wherein in the path of output beam 1858, have only an optical module to be arranged among the OEU 1802.Also can provide embodiment, wherein one or more refraction or diffraction components that are used to influence output beam are arranged in periscope 1836, such as lower surface area 1862, surface area 1864 (shown in the position in, it also will be in the path of Returning beam), angle reflecting surface 1866 (also in the Returning beam path) and 1868 (also in the Returning beam paths), inner surface etc.Optical module in the path of output beam except the control edge strength, also can be carried out other useful (or necessary) functions.Light beam guiding optical module can be configured to calibration of laser beam spots error (for example, because the error that the installation of the off-axis of laser diode 1832 causes etc.).Also can provide to the correction of small part luminous point error by make progress in tangential or footpath translation or rotation OEU 1802.When the beam-forming optics had luminous power on the twocouese (tangential and radially), this kind method was very practical.Usually, scope to the small part of light beam guiding adjustment is subject to the wavefront error of being introduced by site error (optical spot profile and data and the servosignal on the dish of having decayed).Another function that can realize by diffraction in the output beam path or refractive optical components is the astigmatism of calibration of laser diode.Because the surface is normally aspheric, thus can design eliminate some typically LASER Light Source such as laser diode intrinsic astigmatism.

In certain embodiments, the surface of part of O EU 1802 (or other assemblies, such as periscope 1836) is used in absorbing coating 1812 coatings of top 1846 or lower surface 1848 (or on a side or end surface) moulding.Absorbing coating can be used to control the path of unwanted light within the shaven head.Use approaching relatively laser instrument and detector and near many surfaces (surface, periscope 1836, lens 1854 and the lens base plate etc. that comprise substrate 1830, OEU 1802 that may have various reflectivity, exist unwanted light to arrive the potential possibility that photodetector 1844,1828 causes various types of error signals, such as focusing on or tracing deviation).In certain embodiments, in fact allly be not designed to allow the surface of the light by expectation all to scribble absorbability (or reflection) coating.In other method, ray trace (or empiric observation) can be determined the path of not expecting light likely, and positioning design is for making the optimal location of unwanted light minimized black (or low reflection) material area.

Many materials can be used as absorbing coating, such as the simple layer such as the high-absorbent material of germanium or silicon.If desired, can dispose this absorption layer and have additional coating, such as antireflecting coating, with the further performance of improving.In certain embodiments, absorbing coating can be multilayer absorber/antireflection device (such as, chromium/antireflection device multilayer).

In certain embodiments, some zone of OEU (or other assemblies) can be configured to have the reflectance coating 1814 of moulding.Can with these layouts and be configured to carry out the function similar to the absorbing coating of above-mentioned moulding.The reflectance coating of moulding can be used for those unwanted light of deflection, otherwise will drop on the detector.In addition, reflectance coating can help to guide light into detector, such as under the situation of the responsive optics 1804 of forward direction.Reflectance coating can comprise the single or multiple lift metal or alloy from multiple made with suitable reflection and adhesive properties, such as aluminium, gold, silver, chromium etc., perhaps makes from the single or multiple lift dielectric coating.After having understood content of the present disclosure, those skilled in the art will should be appreciated that other the material as reflectance coating.

In certain embodiments, antireflecting coating is configured in selected surface or wherein on the part, for example so that reduce the reflection loss amount of luminous power in the reflection that may cause unwanted signal on detector and/or the reduction system.Usually, antireflecting coating can be used in not on the surface with other surface light contacts of identical refractive index.In this case, when not having antireflecting coating, always have some reflection losses.For example, for typical glass-air interface, reflect about 4% light when incident (normal).Be attached at the OEU1802 solder joint under the situation of periscope 1836, have a gap (typically being several microns), be full of air therebetween, and unwanted reflection will take place, unless use antireflecting coating.In fact adjoin at optical module 1802 under the situation of periscope 1836 (such as, in gummed or glued construction), some or all of opticses 1804,1806,1810 can form by etching or similar processing, so that the zone that is recessed into upper surface 1846 to be provided, thereby creates the clearance.Many materials can be used as antireflecting coating.In one embodiment, apply with predetermined thickness, be generally the single or multiple lift film of dielectric substance such as magnesium fluoride, will reduce or in fact eliminate the light reflection of specific wavelength and angle.After having understood content of the present disclosure, it should be appreciated by those skilled in the art how to select and use these antireflecting coating.

In certain embodiments, in order to help optical alignment OEU,, provide alignment mark 1912,1914 so that be assembled on substrate or the periscope.In certain embodiments, the size of alignment mark 1912,1914 and shape are overlapping or follow respective markers on other assemblies, such as on substrate 1830 or the periscope 1836, so that accurate location, such as being accurate to about 10 microns or littler position.Multiple material and processing procedure can be used to form alignment mark.In one embodiment, alignment mark is the line or the target of lithographic definition, can be in the manufacturing of OEU form during any other the lithography step, and/or with other assemblies, such as forward direction sensing assembly or servo optical assembly etching or coating.Mark can be at upper surface (Figure 19) or lower surface.

In certain embodiments, in fact may combine the optical module that photoetching and/or the etching by moulding in glass (or other optical material) forms all OEU with various applying step.This processing is generally suitable for " extensive wafer " and handles, promptly quite the chip glass or the optical material of big (for example diameter is 3 to 6 inches) can be by the moulding photoetching, to define a large amount of individual components, each parts is all on " chip " scale (such as about 1mm to 5mm or littler).Individual components on all these wafers can be handled (etching, coating etc.) simultaneously, with the independent disk (pan) that causes low cost.Cost further reduces by using photoetching or similar techniques to form a plurality of opticses 1804,1806,1808,1810 on monoblock modules 1802 to be provided, and is scheduled to and is provided at the relative position of the optical module on the module 1802 so in advance with pinpoint accuracy.Like this, can avoid during device fabrication (may be the process of a costliness), the harmonizing cost of single optics particularly for small-scale equipment, such as at the equipment that has a plurality of opticses on the scale of about 1mm to 5mm.

Preferably be formed with the glass or plastics (such as polycarbonate, the acrylic acid etc.) formation of optics before the assembling of OEU 326 usefulness thereon on the precalculated position.When other feasible, preferred glass because it absorbs (or other chemical corrosions) relative insensitivity to temperature and water, and can use high-temperature technology to combine with other assemblies such as Reflow Soldering.In one embodiment, OEU 1802 combines by cohering with periscope 1846.Best, one or two interface surface, have one or more passage or ditches 2102,2104 that form thereon such as the upper surface 1846 of OEU 1802, for example, by sawing or similarly (Figure 21) forms.In one embodiment, the width of each ditch and the degree of depth are approximately 100 microns.In a technology, after the position of the lower surface of the adjustment that upper surface 1846 is arranged in expectation and adjacent prisms or periscope 1836,2106,2108 introduce adhesive along the edge, and make it towards 2110,2112 " migration " or mobile by capillarity.Ditch 2102,2104 absorbs any excessive adhesive, and prevents that in fact adhesive from flowing to outside the position of ditch 2102,2104 (because the adhesive in the ditch 2102,2104 can dock with lens or other opticses potentially).

In one embodiment, under the help from laser diode 612, optics die 326 is arranged in the operable position of expectation.In this embodiment, laser diode was connected to power and control circuit at least before optics die 326 is installed, and can provide enough power to silicon daughter backplane 336, so that the laser output of laser diode 612 to be provided, and alternatively, with the sense photodiode or the similar signal of detector array (comprise those on daughter backplane 1830).In one embodiment, be used for comprising when moving and locate optics die 326, monitor the characteristic of the light that passes through one or two beam-shaping optics 352a, b and/or 354 transmission of servo optics with respect to the positioning equipment of daughter backplane 1830 layouts and installation optics die.Best, use technique known such as Reflow Soldering, with respect to isolator 332,334 optics die 326 is installed.By adopting following processing procedure, promptly wherein when launching, laser instrument (or other light sources) locatees the optics die at light, and wherein the location of light and/or focusing or other characteristics are used in reference to light lead die positioning equipment (preferably with actual automated manner, such as the servo or control signal that is used for positioning equipment by the light that uses detection with definition), the location of optics die is the various errors of compensate for laser (or other light sources) position at least in part.

Also can use active adjustment (active alignment) technology (that is, using during manufacture from the light of laser instrument), so that partly compensate for laser (or other light sources) is with respect to the relative position error of photodetector 356 to help arrangement of components.In one embodiment, after location and fixed optics die, the periscope module of using active adjustment location that object lens preferably have been installed thereon.In one embodiment, a catoptron is arranged in (for example, with the reflection of imitation from CD) near the object lens, and mobile always periscope module, up to the light of reflection form about the expectation of photodetector or near suitable moulding.In at least one embodiment, think that the direction of the longitudinal axis of light arm (that is, perpendicular to) location beam reflected is the most feasible to mobile periscope module in the horizontal.Therefore, think that it is very useful selecting the photodetector to vertically going up the error relative insensitivity of light-beam position at least in certain embodiments.Like this, active adjustment technology can be used to locate the periscope module, is the maximal accuracy of the most responsive light-beam position transversely for error thereby be provided at photodetector.

In some structures, although can arrange optics die 326 before at other assemblies of layout (such as periscope 318, lens 312 etc.), but in a further embodiment, also can be before the optics die 326 of assembling with respect to isolator 332,334, independence assembles some or all periscope 318, quarter wave plate 316 and/or lens 312 are waited until on the optics die 326.No matter the order of various assemblies adjustment and installation how, think that all in fact these embodiment of the present invention provide extensive wafer mounting technology of employing and/or multilayer (piling up) mounting technology to make the benefit that shaven head is brought.By being provided for assembling the relatively inexpensive and practical mode of shaven head with (and in fact static) adjustment of realizing expecting between the assembly, the assembling of whole driver 112 is simplified, this is because strict adjustment is carried out between erecting stage at shaven head, and can be for example realizes in the driver production of low cost relatively or making-up shop that shaven head is not too strict or than the assembling of large redundancy to the requirement of light arm 142.

Use such as Reflow Soldering, cohere or similar mounting technology is installed periscope 318, so that periscope catoptron 322 is arranged on the position of expectation with respect to optics die beam-shaping optics 352ab, promptly in fact be parallel to the data surface of dish 362.In described embodiment, in fact polarization beam splitter 324 is parallel to periscope catoptron 322 (promptly in fact with respect to the about miter angle of vertical direction), and the lip-deep coating (PBS coating) of first module that can be by being arranged in periscope 318, preferably the surface of the terminus module 364 of overlay and periscope 318 is complementary and forms.In fact PBS 324 arrives the polarization of PBS (first polarization) with respect to laser with PBS and reflection way is selected or use.It should be appreciated by those skilled in the art and select how by this way or control polarization or polarization beam splitter.

Correspondingly, PBS (promptly towards dish 362,366) reflect beams of laser light on direction vertically upward.Light beam passes quarter wave plate 316, and passes the object lens of being harmonized by lens base plate 314 usefulness 1/4 wavelength 312 thus.In fact object lens 312 are configured to provide the luminous point size (focusing) with respect to the expectation of the read/write surfaces of coiling 362 (preferably first surfaces).

Although can use the equipment of multiple size and dimension according to embodiments of the invention, shown in equipment in, 314 height 514 is approximately 2.9mm from printed-wiring board (PWB) 338 to lens.In one embodiment, the distance (operating distance of the optical disk system of definition) on the surface from object lens 312 to dish 362 is approximately 0.3mm.

After the arrival dish 362, and according to the part of the dish that is shone and on this position, whether there is data bit, pass object lens 312 and quarter wave plate 316 vertically downward from coiling 362 light that reflect.In this (such as, because by twice quarter wave plate 316), the polarization of reflected light and first polarization are inequality when arriving the PBS coating, and PBS 324 is configured to allow all reflected light to pass through servo optics 354 and photodetector array 356 vertically downward by PBS coating and continuation.

Can use multiple photodetector, comprise 4 quadrant detector, φ detector etc., and the type of servo optics 354 will after having understood present disclosure, it should be appreciated by those skilled in the art these corresponding to employed type photodetector selection.

In one embodiment, substrate 1830 disposes first and second (" A " and " B ") photodetector 2201,2202 (Figure 22), is used to detect the reflected light that is used to provide focusing, tracking and/or data-signal.In an illustrated embodiment, each detector array comprises the parallel detector 2211,2212,2213,2221,2222,2223 of three same shapes.The advantage of panel detector structure that has the detector of three parallel, same shapes in detector array is that output is responsive relatively for the position or the displacement of light beam on the longitudinal direction 2210.Mobile or unregulated adjustment that causes in a lateral direction (vertical with longitudinal direction 2210) actual component with those compared, this means to have relatively large tolerance limit during manufacture, be used for causing the not adjustment (installations of laser instrument 1832, OEU 1802, periscope 1836 and/or lens 1854) of the optical module that moves or harmonize of folded light beam on detector longitudinal direction 2210 (at detector).Help to reduce manufacturing cost for the loose tolerance limit of some adjustment parameter request at least.

Suppose that 2-detector scheme 2201,2202 allows to use difference detecting method.Compare with non-difference (single detection arrays) scheme, Differential Detection provides the performance of improvement usually, at least reduction crosstalk aspect (deviation that tracking-focus crosstalk or light beam distortion cause), this is because differential scheme can suppress common-mode noise between the detector.In one embodiment, tracking-focus crosstalk is less than about 0.25 micron peak-to-peak value (p-p), preferably less than about 0.1 micron p-p.In one embodiment, tracking-focus crosstalk is less than about 5%, preferably less than about 2%.2-detector scheme active configuration as shown in figure 22 can realize by the SOE 1806 that is used for receiving reflection (returning) light beam 1842 and creating first and second folded light beams 2302,2304 as shown in figure 23 for example is provided.As shown in figure 23, guide first and second light beams 2302,2304 to fall the zone of first and second detectors 2201,2202 (Figure 22) respectively, limit first and second areal coverage 2203,2204 of light beam thereon.Best, first and second light beams 2302,2304 have different optical characteristics, such as having different focuses or focal plane position.Can dispose optical system respectively at the opposite side of detector plane 2314 with first and second beam focus.But in the embodiment shown in Figure 23, focus 2306,2308 boths are positioned at the same side on the plane 2314 of detector 2202,2201.The optical characteristics difference of first and second light beams 2302,2304 because have separately focus 2306,2308 at diverse location, is clipped to the different distance 2310,2312 on the plane 2314 of detector such as branch.Owing to multiple reason, in the differential detector scheme, provide the different focuses 2306,2308 of first and second light beams 2302,2304 may be very useful.

In one embodiment, by synthetic each signal of 2211,2212,2213,2221,2222,2223, obtain the focus error signal (FES) of each detector 2201,2202 from three parallel, identical shaped detector region in each detector.According to this embodiment, be used for first or the tracking error signal of " A " detector 2201 be expressed as " FES _A", by will be from the outermost regions of first array, be A ₁2211 and A ₃Negative or the designature of 2213 signal and from central area A ₂2212 signal is synthetic to be obtained.Be expressed as FES with algebraic expression _A=A ₂-(A ₁+ A ₃).Similarly, in this embodiment, the focus error signal that is used for second detector 2202 can be expressed as FES _B=B ₂-(B ₁+ B ₃).As can be seen, by this way, relevant with the light beam areal coverage 2203,2204 that is radiated at detector 2201,2202 from two fes signals of two detectors 2201,2202 each.The big young pathbreaker of areal coverage 2203,2204 according to for example in the pivot focalizer when light arm (or part) rotates 224 (Fig. 2) focus level or the total amount of the luminous point on medium 1856 (Figure 18) change.

Figure 24 A and 24B are the FES that illustrates respectively as the function of amplitude that focuses on medium or degree _AAnd FES _BThe figure of the amplitude of signal 2402a, 2402b.On the one hand, focal length can be expressed as the distance 1862 (for example, with micron represent) of object lens to the Information Level 1864 of medium 1856.For the focus 2306,2308 of first and second light beams 2302,2304 provides an effect of different distance 2310,2312 be, the structure from the fes signal of two detectors 2201,2204 as the function of focal length is different, for example, can find out by comparison diagram 24A and 24B.Each independent fes signal 2402a, 2402b is actually nonlinear (deep camber) near regional 2406a, 2406b expectation or the nominal focal length.This non-linear making with any focus error signal FES _A, FES _BThe control signal that focuses on as control is difficult and/or inaccurate relatively separately.But, as shown in figure 25, when with FES _BNegative or designature 2404 and the FES of signal 2402b _AWhen signal 2402a synthesizes, resulting synthetic focusing error signal FES _A-FES _B2502 are actually linear being positioned near the nominal focus 2506 catching range 2504.Therefore, provide two different focal lengths 2310,1312 as described (in an illustrated embodiment, two the same sides that all are positioned at detector plane 2314) differential scheme helps to provide linear in fact difference focus error signal in capture region 2504 at least, can be used for controlling focusing motor or executive component.In one embodiment, capture region is the zone of nominal focus ± 10 micron.In one embodiment, resultant error signal FES _A-FES _B2502 maximum linears on any point of capture region depart from (that is, leaving optimum straight line) less than about 10%, preferably less than about 2%.

In a similar manner, synthetic tracking error signal can be defined as TES=(A ₁-A ₃)+(B ₁-B ₃), the generated data signal can be defined as Data=(A ₁+ A ₂+ A ₃+ B ₁+ B ₂+ B ₃).In one embodiment, the synthetic maximum linear of tracking error signal TES on any point of capture region departs from (that is, leaving optimum straight line) less than about 10%, preferably less than about 2%.

If desired, FES and TES can be normalized to the general power in each signal, for example with reduce the influence that signal amplitude changes (such as because the vignette of the difference in reflection XOR light beam of dish is for example to the overshoot or the similar influence of executive component).For example, normalized FES and TES signal can be provided as FES _Normal=[(A ₁+ A ₃-A ₂)/(A ₁+ A ₃+ A ₂)]-[(B ₁+ B ₃-B ₂)/(B ₁+ B ₃+ B ₂)], and TES _Normalized=[(A ₁-A ₃)/(A ₁+ A ₃)]+[(B ₃-B ₁)/(B ₁+ B ₃)].Each composite signal from the zone of two detectors can be synthetic with simulation or electronics mode, perhaps can digitizing and digitally synthetic (or combination of two kinds of methods).

In one embodiment, for with respect to the different groove geometry of object lens and/or medium 1856 (fluted on the medium) or have the different detector positions of different pit geometries on the medium of prefabricated premaster pit, the relative size of the core 2212,2222 of each detector can be adjusted, to reduce tracking signal TES crosstalking to focus signal FES.

Figure 12 illustrates and is provided to and from an example of shaven head 128 electrical communication mode.Although the embodiment of Fig. 6 supposes daughter backplane 336 and arranges with respect to printed-wiring board (PWB) 338 that in the embodiment of Figure 12, daughter backplane 336 is placed in the stripping and slicing 1212 that forms in the flexible circuit (such as the flexible circuit of Kapton-copper) 338 '.Flexible circuit 338 ' preferably is electrically coupled to shaven head 318, such as welding by the line that forms between bare headed pad 1216 and the flexible circuit pad 1218.Flexible circuit 338 ' can for example pass through such as what sell down with trade mark Epo-Tek H70E-2, and from Billerica, epoxy resin or other binders that the Epoxy Technology company of MA obtains physically are coupled.Some or all flexible circuit or other parts for example can apply or seal in order to protect.Flexible circuit 338 ' preferably includes some or all control that is used for shaven head 128 and/or the electronic unit of signal Processing.After having understood present disclosure, it should be appreciated by those skilled in the art other be provided to and from the mode of the electronic communication of shaven head.

According to embodiments of the invention, an important factor is relevant with heat management when designing apparatus.Most laser diodes or other light sources are important thermals source.In addition, many electric or electronic packages, such as power supply or regulator, resistance, diode and other, will increase total heat load.The laser apparatus of power output near 200 milliwatts used in expectation.Temperature rises and may damage or reduce the electronic package in the driver, among the PED or other equipment of merging driver and/or the performance of medium.Fully change performance characteristic when laser instrument and other assemblies may have some, and fully compensate these and change very difficulty and spend huge as the function of temperature.In addition, the product that generates heat will reduce its commercial complaint with perceiving.Previous electronics or electrical-optical equipment use relatively large, heavy or the big assembly of power consumption usually, such as big and/or heavy heating radiator, fan etc.But the present invention is preferably small-sized (or other are little) equipment, and be specially adapted to (although not necessarily must be subject to) with PED or other little, in light weight, low power consuming devices uses.Therefore, preferably dispose shaven head with the concentrated or big calorimetric of avoiding heat and/or the mode of avoiding possibility damage equipment or assembly maybe may reduce the temperature increase of performance.Preferably, at least in one embodiment, the part of the downside of flexible at least circuit 338 ' (preferably including the part 1214 that expands to some or all stripping and slicing zone 1212) has such as the coating of the heat conducting material of copper or layer, as for example heating radiator or heat dissipation device.In one embodiment, daughter backplane 614 (if existence) is in fact formed by heat conducting material, such as aluminium nitride or silit.Daughter backplane (for example has relatively large surf zone, compare with the areal coverage 612 and/or the base plate 614 of laser diode) on relatively large surf zone, the heat that laser instrument was generated is left effectively, avoid heat to concentrate and unnecessary (part) temperature rise.

Except providing heat management and shaven head 128 to the beam coupling of light arm 142, embodiments of the invention also comprise provides shaven head 128 to install or coupling with respect to the machinery of light arm 142.In the embodiment shown in fig. 13, the first and second smooth arm 1312a, b definition one is used to hold bare headed zone 1313.A plurality of flexible pin 1314a, b, c, d are coupled to the light arm.Pin has and is configured to part, projection 1316a with certain angle, b, c, the d of shaven head at regional 1313 o'clock contact shaven heads.In case shaven head (is for example located as expected, use the mechanical hook-up of firmly grasping and moving shaven head), projection can be such as using binder to be fixed to the part of shaven head, preferably such as by use epoxy resin or other rigidizers projection being hardened or fixing, as using ultraviolet ray or other cure step.

Figure 14 illustrates one embodiment of the present of invention, wherein detector 1412 is arranged in the outside of magnifier module 332.In this embodiment, PBS 1424 is arranged and be configured in fact will be reflected into horizontal route 1432 from the light 1426 that laser light source 1428 receives.By reflecting surface 1438 light is reflected into vertical-path 1434 towards object lens 312 then.1434,1432 reflected light that return, still have the polarization of change send along horizontal route 1442 by PBS 1424 along similar path, reflect 1444 downwards towards detector 1412 by reflecting surface 1446.In one embodiment, the lower surface of the optical module 326 ' in the zone around the path of folded light beam 1444 scribbles absorbing coating, such as non-reflection (black) chromium, avoids the interference of parasitic light to help detector 1412.In one embodiment, the reflectance coating of one ring-type is arranged on the lower surface of the optical module 326 ' around the position of core of light beam 1426, so that the outermost annulus downward 1446 of light beam is reflexed to feedback detector 1448, is used to control laser power.Absorbability or reflectance coating can be coated in other zone, are used to control parasitic light, and this will be perfectly clear after having understood content of the present disclosure for a person skilled in the art.

An alternative embodiment of the invention as shown in figure 10.Although Figure 10 shares some feature of the embodiment of Fig. 3-6, but in Figure 10, in fact silicon (or the similarly) daughter backplane 1036 that laser instrument 1012 and detector 1056 are installed on it arrange with vertical position, that is, and and in plane perpendicular to the surface of dish 1062 or plane.Optics die 1026 separates daughter backplane 1036 by isolator 1032,1034 to be installed, and backhaul catoptron 1018 is absolute construction.Pass beam-shaping optics 1052ab from the light of laser instrument 1012 and enter magnifier module 1022.The read/write light beam is by 1024 reflections of inner PBS surface, downwards by quarter wave plate 1016 and object lens 1013 arrival dishes 1062.Have the reflected light that has changed polarization and pass PBS 1024, and surface 1023 reflections that are reflected, by the servo optics 1054 arrival photodetectors 1056 of optics die 1026.Although the equipment of multiple size and shape can use with the present invention, in one embodiment, the vertical height 1072 of optics die 1026 and module 1022 is approximately 1.8mm, and the height 1074 of the lens of quarter wave plate and installation is approximately 1.02mm.In one embodiment, the lateral dimension 1076 of optics die 1026 and module 1022 is about 4.0mm.

An alternative embodiment of the invention is shown among Figure 16.In the embodiment of Figure 16, laser instrument 612 is not mounted on the chip or daughter backplane that separates with photodetector 356, and is mounted on the lower surface of optics die 326.In an illustrated embodiment, for example optionally metallize or apply so that provide and for example be used to surround photodetector 1512 to control the zone that spuious reflection of light or absorbability zone and/or definition are used for coupling light electric explorer 356, laser instrument 612 or other assemblies or circuit in the zone of the lower surface of optics die 326.In one embodiment, a surface of the laser diode front end (lead) 1514 etc. that is used to be coupled is so that provide power, data or control signal to laser instrument 612 with from laser instrument 612.In one embodiment, the Free Surface of laser instrument 612 can be directly coupled to heating radiator (comprise if desired some or all light arms), is used for heat management efficiently.The structure of Figure 16 not only can provide heat management efficiently, and by avoiding using silicon plate 338 or daughter backplane 336 can reduce required vertical height, further improves the compact nature of shaven head.

An alternative embodiment of the invention is shown in Figure 26.In the embodiment of Figure 26, provide the second beam separation surface 2602 as part periscope 2604, so that be provided for shining first and second reflected beam path 2606,2608 of first and second detector arrays 2610,2612.The embodiment of Figure 26 can compare with the embodiment of Figure 18 and 23.In Figure 23, SOE optics 1806 is carried out two functions: separating folded light beam 1842 is first and second light beams 2302,2304, and two different focal lengths 2310,2312 are provided.(combining with the effect on initial beam separation surface 324) because this extra beam separation surface 2602 causes the folded light beam 2606,2608 of separating on two spaces, no longer needs to provide the servo optics of the beam separation function of the type that is configured to carry out as shown in figure 23.If desired, also may exempt from and revise or change luminous power on the light beam 2606,2608 that is applied to two reflections or returns (making it possible to thus eliminate) for returning or the servo optics of reflected beam path 2606,2608 or all any needs of other optical devices.For example, can arrange the measurement of difference size as shown in figure 27, Figure 27 shows that is passed the second backhaul light beam that detector array 2612 forms the backhaul light beam of a virtual focus point 2702 and forms real focus 2704 in second detector array, 2610 fronts.Since focus the 2704, the 2702nd, the true picture of luminous point on dish (arriving the identical luminous point of distance that coils) with obvious laser light source point, thus do not need additional focusing power, and saved SOE thus.

An advantage saving SOE (such as in the embodiment of Figure 26 and 27) is to help calibration of laser luminous point error.When OEU comprises output beam former optics 1808,1810 (Figure 18) and backhaul or folded light beam optics 1806, for calibration of laser luminous point error ratio when adjusting OEU 1802, also with mobile SOE 1806.Moving of this SOE 1806 can cause error (potential not recoverable error) in the record of SOE 1806 and detector array 1844.If can save SOE assembly 1806, then can adjust OEU 1802 installation site (such as, calibration of laser luminous point error) and need not mobile SOE assembly.Required any detector is harmonized and can be carried out by other parts, such as mobile object lens 1854.

In view of foregoing description, plurality of advantages of the present invention as can be seen.(for example the present invention includes generally acknowledged and high data density, by the facility of using the first surface medium to be brought) compatible little spot definition makes that for example to provide in fact all optical modules to become feasible in little and/or light encapsulation, thereby can be by moving whole optical package or shaven head execution tracking and/or focusing on (in contrast, for example, only mobile object lens).The invention provides an equipment, not only enough little and light so that keep all optical modules to be in a fixed position with respect to another, and provide these assemblies in different directions can spatial spread, such as little vertical (low profile) shaven head is provided so as with at little and/or portable set or main process equipment, such as personal electronic equipments in the profile key element type used compatible mutually.The present invention can provide a kind of efficient shaven head, such as in fact avoid overflowing or other spill the optical design of light or other energy by using.The invention provides the design that a kind of some or all manufacturing steps can be realized in cheap relatively mode, such as using extensive wafer fabrication and/or using the plane of assembling shaven head or pile up technology.A feature that comprises the optical device of a plurality of optical modules on the different surfaces of one or more optical modules disclosed herein is, substantial most of optical path links from the LASER Light Source to object lens only have a minimum part to pass through air by solid-state (glass or other) medium.In one embodiment, the light path from the LASER Light Source to object lens in glass or other solid state mediums the ratio of (relative therewith, as to pass through air) greater than about 50%, more preferably greater than about 75%, more preferably more preferably greater than 85%.In one embodiment, total optical path length is approximately 5500 microns, and about 5000 microns path link is by glass (or other solids) substrate (for example, optical module 1802 and periscope 1836).450 microns of approximately total light path by 1802 air from the laser instrument to OEU, other path parts by air occur between optical module 1802 and the periscope 1836 potentially and/or periscope 1836 (or quarter wave plate 316) and object lens 1854 between interface.

Can use multiple variation of the present invention and modification.Can use some aspect of the present invention, and not adopt other aspects.For example, can provide enough little and/or light shaven head, make moving whole shaven head becomes possible (for example, being used for following the tracks of and/or focusing on), and need not extensive wafer described here and/or pile up manufacturing technology.In one embodiment, in optics die 326 independently or on provide shown in some or all opticses can be in periscope or optical module 322 or on form, making thus need not provide or assemble independent optics die 326 and provide embodiments of the invention to become possible (that is, directly prism/the optical module of arrangement combinations on isolator 322,324).Similarly, although embodiment be with in fact all optical modules (may except object lens and quarter wave plate) in two unit (optical module unit and periscope) or go up and form, can use three or more unit to realize the present invention so that these optical modules to be provided.Although among the embodiment shown here, use polarization beam splitter to distinguish emission and reflected light, but also can use other technologies or battery limits to divide emission and reflected light 1722 (Figure 17), comprise diffraction grating, after understanding present disclosure, it should be appreciated by those skilled in the art this point.Although at this embodiment (can be used to reduce the profile height and can not limit optical path length) that has described the variation that periscope is wherein used provides both direction (vertically to level and level to vertical), a plurality of internal reflections between the wherein use (typically parallel) surperficial (such as three or more) also can be provided, for example be used to reduce the structure of bare headed profile.In certain embodiments, can preferably dispose this system, so that periscope prism (or assembly of other shaven heads that pile up) structural symmetry (for example, to improve manufacturing capacity) in fact.The optical module of all in fact shaven heads is the embodiment that fixes with respect to another although described wherein, but movably operating structure of some assembly also can be provided wherein.For example, but can make up an operating equipment, wherein object lens can be movable with respect to one or more assemblies of shaven head, for example is used for meticulous (or approximate) focusing, tracking etc.Although described the embodiment that wherein uses extensive wafer and/or stacking method, also can use integrated optics technique that some or all of optical modules is provided, after having understood the present invention, it should be appreciated by those skilled in the art this point.Although be the equipment that provides around the axle rotation that is parallel to turning axle by the light arm in conjunction with wherein following the tracks of, having described periscope part and/or in fact all assembly can not movable relatively shaven head, but also can dispose the equipment that shaven head wherein described here otherwise moves, such as the linearity that provides track (rail) or similar devices to be used to realize shaven head (such as, radially) pursuit movement.Has diode 1712 (Figure 17) or other laser instruments embodiment although described as light source at this, but also can provide the embodiments of the invention that use non-laser, for example, provide superfluorescence diode 1714, incandescent lamp, fluorescent light, arc lamp, gas lamp or other light sources.Also can provide optical transmission module as the light source in the shaven head, for example output 1716 of optical fiber or other optical transmission devices, will by can be arranged in if desired the outside laser instrument of shaven head or other photoproduction grow up to be a useful person 1718 light transmission that generate to or go into shaven head.Use optical fiber helps heat management (for example, by adopting the laser instrument of installing away from shaven head) and/or circular light beam is provided.

In different embodiments of the invention, be included in this actual assembly, method, processing procedure, system and/or device of describing and illustrating, comprise each embodiment, sub-portfolio and subclass etc.After having understood present disclosure, it should be appreciated by those skilled in the art how to carry out and use the present invention.In different embodiment, the present invention includes provides equipment and the processing procedure that lacks the content that does not have explanation and/or describe in this or each embodiment, comprise and lack the content that those have used in existing equipment or processing procedure, for example, be used to improve performance, realization facility and/or reduction and realize cost.The present invention includes novel content and before have and/or analogue technique in reorganization and the term that comes, novel teachings or processing procedure for convenience of description there is no need to keep the various aspects of conventional these terms that use.

The of the present invention above-mentioned discussion that has presented is used for the purpose of illustration and description.Aforementioned is not that the present invention is limited to form disclosed herein.Although description of the invention has comprised the description of one or more embodiment and some variation and modification, but other variations and modification do not exceed scope of the present invention, for example those skilled in the art is after having understood present disclosure, within these variations and modification possibility those skilled in the art's the skills and knowledge scope.But seek out the right that includes alternative embodiments to allowed band, comprise that claim is replaced, exchange and/or structure, function, scope or step of equal value, no matter whether structure, function, scope or step these replacements, exchange and/or of equal value be open at this, and can not disclose exclusive any patent main body.

Claims (31)

1. one kind is used in the shaven head that is used for read/write medium in the optical read/write device, comprising:

Light source is at initial light outgoing position output light; At least one first photodetector array is installed on the fixing position with respect to described initial light outgoing position, and described first photodetector array has the first surface at least one definition photodetector plane;

Optical member unit, be installed on the fixed position with respect to described smooth outgoing position, described optical member unit has the first and second beam-shaping opticses of the light that is received in described smooth outgoing position output, described optical member unit also comprises at least one the 3rd optics, is configured to be used in reference to cause a few part and arrive described first photodetector array along a path from the light of described dieletric reflection;

Described shaven head provides at least one first light path, and wherein said first light path is from described initial light outgoing position, and the described at least read/write medium of arrival; And

Second optical module is installed on the fixed position with respect to described optical member unit, and described second optical module is configured at least in part folding described first light path, with limit be not vertical described first light path at least a portion.

2. shaven head as claimed in claim 1, wherein said optical member unit have the first and second relative surfaces, and the wherein said first and second beam-shaping opticses form on described first and second surfaces respectively.

3. shaven head as claimed in claim 1, wherein said optical member unit also comprises at least one the 4th optics, be configured to the first from described dieletric reflection light at least provides first focal plane, described first focal plane and first photodetector array separate one first distance.

4. shaven head as claimed in claim 3, wherein the optics that provides in described optical member unit further is configured to provide second light beam from the described light of the described dieletric reflection of at least a portion, and described second light beam irradiates is to second photodetector array that separates with described first photodetector array.

5. shaven head as claimed in claim 4, wherein said second light beam has second focal plane that separates a second distance with described second photodetector array.

6. shaven head as claimed in claim 5, wherein said second distance and described first distance are inequality.

7. shaven head as claimed in claim 5, wherein said first focal plane and described second focal plane are positioned at the same side on described photodetector plane.

8. shaven head as claimed in claim 5, wherein said first and second focal planes are at the opposite side on described photodetector plane.

9. shaven head as claimed in claim 5, wherein said first photodetector and described second photodetector array be copline in fact.

10. shaven head as claimed in claim 1, wherein said second optical module comprises at least one first beam splitter, is used for the first at least of the described light of described dieletric reflection is guided into along having at least a portion second light path different with described first light path.

11. shaven head as claimed in claim 10, wherein said second optical module comprises second beam splitter.

12. shaven head as claimed in claim 11, wherein at least one described first and second beam splitter is polarization beam splitters.

13. shaven head as claimed in claim 1, wherein under the situation of the optics of the focal plane that lacks the light that is configured to change described dieletric reflection, described optical member unit is provided.

14. shaven head as claimed in claim 1, wherein optical member unit also comprises the responsive optics of at least one first forward direction, is configured to be used for to guide a forward direction sensing detector into to small part light from described first light path.

15. shaven head as claimed in claim 14 also comprises the circuit of use from the power level of the described light source of signal controlling of forward direction sensing detector.

16. shaven head as claimed in claim 1 also is included in the coating at least a portion of first surface of described at least optical member unit.

17. shaven head as claimed in claim 16, wherein said coating is actually a reflectance coating.

18. shaven head as claimed in claim 16, wherein said coating is actually absorbing coating.

19. shaven head as claimed in claim 16 is wherein arranged described coating so that reduce the incident of parasitic light on described photodetector.

20. shaven head as claimed in claim 16, wherein said coating is an antireflecting coating.

21. shaven head as claimed in claim 1, wherein said optical member unit have at least one first alignment mark, are arranged on the first surface of described at least optical member unit.

22. shaven head as claimed in claim 1, wherein said light source is an edge emitter laser.

23. shaven head as claimed in claim 1, wherein said light source is VCSEL.

24. shaven head as claimed in claim 1, wherein said light source is a blue laser.

25. that shaven head as claimed in claim 1, the first surface at least that wherein adjoins the described optical member unit of described second optical module comprise is that at least one forms thereon, adjoin to the first ditch district at the edge on the described surface of small part.

26. shaven head as claimed in claim 25, wherein said ditch hold the adhesive of introducing along described edge to small part, described adhesive extends internally from described edge, does not exceed described ditch.

27. shaven head as claimed in claim 1 also comprises object lens, each the circumferential location place at edge that limits described object lens is with respect to the edge intensity of central light strength, and wherein said edge intensity is less than about 80% on tangential direction.

28. shaven head as claimed in claim 1 also comprises object lens, each the circumferential location place at edge that limits described object lens is with respect to the edge intensity of central light strength, and wherein said edge intensity is less than about 80% on the radial line direction.

29. shaven head as claimed in claim 1 also comprises object lens, each the circumferential location place at edge that limits described object lens is with respect to the edge intensity of central light strength, wherein said edge intensity on tangential direction greater than about 50%.

30. shaven head as claimed in claim 1 also comprises object lens, each the circumferential location place at edge that limits described object lens is with respect to the edge intensity of central light strength, wherein said edge intensity on the radial line direction greater than about 15%.

31. shaven head as claimed in claim 1, wherein greater than the path of 50% described first light path in solid-state structure, and the described path that is less than 50% described first light path is in air.

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