Abstract: When generating an origin signal of an encoder having a scale on which an incremental pattern and the origin pattern are formed, an origin signal having a necessary position and width is generated by software based on an origin waveform obtained from the origin pattern. This enables origin detection with excellent repeatability, S/N ratio (pulse width), and bidirectionality while maintaining ease of mounting and adjustment.

Abstract: An image reading apparatus includes: plural image pickup elements which are arranged unidirectionally, each image pickup element including plural photoelectric transducers that convert reflected light from an original document into pixel signals, and a forwarding unit that serially forwards pixel signals acquired by the photoelectric transducers; a dividing unit that divides outputs of the photoelectric transducers into plural processing paths so that pixel signals acquired by photoelectric transducers located on both sides of a boundary between adjacent image pickup elements are included in the same division unit; and an interpolation unit that executes pixel interpolation, using the pixel signals acquired by the photoelectric transducers located on both sides of the boundary among the pixel signals divided by the dividing unit.

Abstract: An adaptive print driver receives printing instructions relating to a document and outputs print data pages to an imager. The adaptive print driver includes a printing instruction parser for parsing printing instructions, a format controller for assigning a data format to the parsed print instructions and transferring the parsed print instructions according to the data format to a plurality of format generators. The plurality of format generators generates print data which is passed to a coalescer that coalesces the received print data into at least one print data page. The adaptive print driver uses a data format determination analysis process to balance rasterization on the adaptive print driver to achieve an optimal load balance between rasterization to take place on the adaptive print driver and rasterization to take place on the imager.

Abstract: A monocular holographic storage device or system to provide for compact recording and/or reading of data pages in a holographic storage medium. Also provided are methods for carrying out such data storage and/or data recovery using a monocular holographic storage device or system. Further provided are articles comprising holographic storage media for recording or for reading recorded data using such devices or systems.

Abstract: In one embodiment of an optical scanning apparatus, a light blocking member is provided that is disposed facing a reflective face of a polygon mirror near the reflective face, and blocks stray light without blocking light in an effective scanning range of a laser beam. The light blocking member includes a light blocking plate having an opposing face that faces the reflective face of the polygon mirror, a support plate that supports the light blocking plate, and a fixing plate that fixes the lower edge portion of the support plate to a support member. The opposing face of the light blocking plate is inclined relative to the reflective face of the polygon mirror, and a space below the light blocking plate is open.

Abstract: Provided is a space scanner for a self-control moving object. The space scanner has a structure in which a reflective mirror is rotated and tilted. Thus, the space scanner can scan a moving object in horizontal and vertical directions to secure spatial-data, thereby performing a self-control movement.

Abstract: Particular embodiments relate generally to systems and methods of reducing the appearance of speckle in laser projection images. According to one embodiment, a laser projection system includes a light source, scanning optics and spinning optics. The light source includes at least one laser configured to emit an output beam. The scanning optics is positioned in an optical path of the output beam and configured to scan the output beam across a plurality of image pixels onto the spinning optics. The spinning optics is configured to create a virtual image of the scanning optics, translate the virtual image and change the angle of incidence of the output beam. The laser projection system is programmed to generate at least a portion of a scanned laser image, execute the translation of the virtual image by moving the spinning optics, and compensate for a relative image shift resulting from the translated virtual image.

Abstract: An optical beam scanning apparatus according to the present invention includes a pre-deflection optical system, a post-deflection optical system at least including one or plural first optical elements, plural second optical elements, a first reflection mirror which is provided in optical path between the first optical element and one of the second optical elements and reflects, on a most upstream side of the optical paths, a luminous flux on a most downstream side or a most upstream side in the sub-scanning direction among the plural luminous fluxes, and a second reflection mirror which is provided in optical path between the first optical element and another second optical element and reflects, on an optical path second from a most downstream side of the optical paths, the luminous flux on the most downstream side or the most upstream side in the sub-scanning direction among the plural luminous fluxes.

Abstract: An optical scanner is disclosed that has an optical source unit that emits a laser beam; a vibration mirror by which the laser beam from the optical source unit is deflected to scan; a driving circuit that vibrates the vibration mirror based on a driving signal generated from a reference clock; a light-receiving element that receives the laser beam within the scanning area of the laser beam; and a controlling unit that corrects the driving signal so as to make a phase deviation between the reference phase clock and the output signal of the light-receiving element constant.

Abstract: Implementations of actuators that use flexures to provide support to the actuators and pivoting mechanisms to the actuators. Such actuators can be electromagnetically activated actuators that include a magnet stator and a coil rotor mounted on a flexure.

Abstract: A color filter including a substrate, a plurality of pixel units and a transparent electrode layer is provided. The substrate has a plurality of pixel regions. Each pixel region has a plurality of first sub-pixel regions and a second sub-pixel region. Each pixel unit is disposed in one of the pixel regions corresponding thereto and includes a plurality of and a white filter film. Each color filter film is disposed in one of the first sub-pixel regions corresponding thereto and the white filter film is disposed in the second sub-pixel region. Since the area of the white filter film is larger than the area of each color filter film, the color filter has high light-transmittance. The transparent electrode layer is disposed on the pixel units. Furthermore, a color reflective display device with the color filter is disclosed.

Abstract: This invention discloses corrosion resistant metal compositions that may be used to form nanoparticles or for coating of particles. Further, such particles may be used to fabricate printable transparent conductors that may be used in electronic devices. Electrochromic displays formed using such conductors are described.

Abstract: A system for producing modulated lights disclosed. The system comprises a spatial light modulator including a light modulating medium switchable between different states so as to act on light in ways which form overall patterns of modulated light. The system also includes an arrangement for switching the modulating medium between the different states in a controlled way and an illumination arrangement for producing a source of light. The system, further includes an optics arrangement for directing light from the source of light into the spatial light modulator and for directing light from the spatial light modulator through a predetermined source imaging area. The optics arrangement cooperates with the illumination arrangement and the spatial light modulator so as to produce a real image of the source of light within the source imaging area such that an individual is able to view a virtual image of the overall patterns of modulated light from the source imaging area.

Abstract: A display with a photovoltaic (PV) cells integrated as the front side and/or back side of the display is disclosed. Ambient light may reach a PV cell situated behind a display through fully or partially transmissive features within the display. Display-generated light may also reach a PV cell behind a display. A transmissive PV material situated in front of a display may collect both ambient light as well as display-generated light.

Abstract: An electrophoretic light modulator includes a plurality of similarly charged particles comprising a first optical characteristic. The electrophoretic light modulator also includes at least one reflecting surface comprising a second optical characteristic different that the first optical characteristic. The electrophoretic light modulator further includes a pair of electrodes that create an electric field that causes the plurality of charged particles to obscure or expose the reflecting surface based on the polarity of the electric field.

Abstract: An optical amplifying medium, a method of manufacturing the optical amplifying medium are provided, and an optical device comprising the optical amplifying medium. The optical amplifying medium includes a multi-layer structure in which a first material layer doped with an activator and a second material layer that comprises a sensitizer are stacked.

Abstract: An optical waveform reshaping device, including a semiconductor optical waveguide which has an active layer, wherein: optical amplification regions and optical absorption regions are installed alternately along the semiconductor optical waveguide; one optical amplification region is set longer than the other optical amplification regions so that a desired amplification factor can be obtained when power of an input optical signal is at an ON level; a power level is maintained by the other optical amplification regions excluding the one optical amplification region and by the optical absorption regions when the power of the input optical signal is at the ON level; and when the power of the input optical signal is at an OFF level, the input optical signal is absorbed by the optical absorption regions so that a power level of an output optical signal will not be higher than the power level of the input optical signal.

Abstract: A telescope imaging system includes a first lens group for receiving a spot light and generating a first refracted beam, a second lens group for receiving the first refracted beam and generating a second refracted beam, a third lens group having a convex lens disposed at a side of the third lens group distant from the spot light for receiving the second refracted beam and generating a parallel beam by an effective focus formed by the first lens group, the second lens group and the third lens group, a first reflective mirror having an opening, receiving the parallel beam and generating a reflected beam, and a second reflective mirror adjacent to the third group lens and reflecting the reflected beam for allowing the reflected beam passing through the opening and focused as an image.

Abstract: There is provided a screen and a projector using a simple configuration and operation to make speckles less visible. A screen 10 on which light beams are incident includes a lenticular lens 11 as a first layer having viewing angle control means for enlarging the viewing angle and a Fresnel lens 12 as a second layer having angular conversion means for converting the angles of incidence of the incident light beams into the substantially same direction. One of the first and second layers has a diffusion capability that diffuses the incident light beams and has moving means for moving that layer relative to the other. Alternatively, the first and second layers both have the diffusion capability, and at least one of the layers has moving means for moving that layer relative to the other.

Abstract: An optical deflecting sheet for a transmission type screen that emits imaging light projected from an incident side to an emergent side. The optical deflecting sheet includes a highly rigid substrate layer with a light-transmissibility and a high rigidity, and a plurality of layers laminated on the substrate layer. The plurality of layers includes at least a pair of anti-scattering layers disposed on opposite sides of the substrate layer for preventing scattering of the substrate layer. At least one layer of the two or more layers includes an optical deflecting element that deflects imaging light by refracting or reflecting the imaging light. The optical deflecting element is a prism part formed by arranging a plurality of unit prisms each having an incident surface on which light is incident and a total reflecting surface for reflecting at least a part of light incident on the incident surface.

Abstract: A polarization element has a polarizer with an aggregate of metal pieces: Plasmon resonance frequency of a metal piece varies according to the polarization direction of a irradiated on it. In the polarization element, the plasmon resonance frequency in a predetermined direction of a metal piece is substantially equal to the frequency of light irradiated on the polarization element. The real part and the imaginary part of permittivity at the plasmon resonance frequency of a metal piece's constituent material and the refractive index (na) of a dielectric layer satisfy a particular relation.

Abstract: A mirror unit consists of a half mirror and a mirror unit. The half mirror generates a transmitted light and a reflected light. A pair of the mirror units is arranged on one side and the other side of the half mirror so that the transmitted light and the reflected light split by the half mirror are deflected and are combined again at a common place on the half mirror. The mirror unit also has plural mirrors and is arranged to make the optical length variable by shifting the mirror unit toward one direction with a moving mechanism.

Abstract: The invention relates to optics comprising adjustable optical elements and, if desired, lenses of fixed focal lens. By use of an appropriate controller for the adjustable optical elements, characteristics of the optics can be advantageously varied. For this purpose, systems are provided which are suitable for use as surgical stereo-microscope, objective, ocular or zoom. A zoomable imaging optics comprises lenses and of variable optical power, which are oppositely controlled by means of a controller to change an imaging ratio, so that the optical power of the one lens is increased and the optical power of the other lens is decreased. Moreover, the imaging optics may comprise still further assemblies of fixed optical power.

Abstract: A liquid lens system comprises a liquid drop 10 whose shape can be influenced by electrical fields. A plurality of electrodes are arranged annularly around the liquid drop. The liquid lens system may be employed in an artificial eye, an accommodation measuring instrument and a dioptric telescope.

Abstract: Provided is a zoom lens system including, in order from an object side to an image side: a first lens unit having a positive optical power; a second lens unit having a negative optical power; a third lens unit having a positive optical power; a fourth lens unit having a negative optical power; and a fifth lens unit having a positive optical power. In this zoom lens system, magnification sharing between the fourth lens unit and the fifth lens unit, and a movement amount of the second lens unit as a principal magnification lens unit are set appropriately, so as to realize a high zoom ratio and high optical performance over an entire zoom range.

Abstract: An electronic image pickup apparatus comprising a zoom lens system and an image pickup device disposed on an image side of the zoom lens system and which converts an image formed by the zoom lens system into an electric signal, the zoom lens system having, in order from an object side, a negative first lens unit, a positive second lens unit, a negative third lens unit, and a positive fourth lens unit, the first lens unit having, in order from the object side, a negative lens and a reflective optical element which reflects an optical path, and during zooming from a wide-angle end to a telephoto end, each space between the lens units which are adjacent with each other being changed, the first lens unit being arranged in a fixed position to the image pickup device, and at least the second lens unit and the third lens unit being moved.

Abstract: Provided is a zoom lens system including a compact focusing lens unit and having a suppressed change in image magnification at the time of movement of the focusing lens unit. The zoom lens system of the present invention, in order from an object side to an image side, includes a first lens unit G1 having positive optical power, a second lens unit G2 having negative optical power, a third lens unit G3 having negative optical power, and a fourth lens unit G4 having positive optical power. At the time of zooming, all lens units moves in a direction along the optical axis such that intervals among respective lens units varies. Further, at the time of zooming, the third lens unit G3 moves in the direction along the optical axis such that the interval between the second lens unit G2 and the third lens unit G3 is made longer at a telephoto limit than the interval at a wide-angle limit. Still further, condition (6): ?1.6<fF/f4?<?0.

Abstract: An endoscope objective optical system used in an endoscope has an objective optical system including a first lens group having a positive refractive power, an aperture stop, a second lens group having a negative refractive power and a third lens group having a positive refractive power, the first lens group, the aperture stop and the second and third lens group being successively disposed from the object side. The second lens group is made movable along an optical axis to change the focal length of the objective optical system. The lens surface at the object-side outermost position in the first lens group is formed so as to be convex on the object side.

Abstract: An image pickup lens includes, in order from an object side thereof: a first lens in a meniscus shape having a positive refractive power and including a convex surface facing the object side; a second lens having a negative refractive power and including a concave surface facing an image side of the image pickup lens; a third lens in a meniscus shape having a positive refractive power and including a convex surface facing the image side; and a fourth lens having a negative refractive power and including a concave surface facing the image side, where at least one surface of the fourth lens is in an aspheric shape. The image pickup lens satisfies a predetermined condition relating to a composite focal length of the first lens and the second lens, and a focal length of a total system of the image pickup lens.

Abstract: An imaging lens is provided and includes: in order from an object side thereof, a first lens of a negative lens having a concave surface on an image side thereof and having at least one aspheric surface; a second lens of a positive lens having at least one aspheric surface; a stop; and a third lens of a positive lens having a convex surface on the image side thereof and at least one aspheric surface. The following Conditional Expressions (1) and (2) are satisfied. 1.5<vd3/vd2??(1) 0.0<|f1/f23|<0.5??(2) In which vd2 represents an Abbe number of the second lens at the d-line, vd3 represents an Abbe number of the third lens at the d-line, f1 represent a focal length of the first lens, and f23 represents a composite focal length of the second and third lenses.

Abstract: A magnetic recording/reproducing apparatus 100 includes: a magnetic head 1; a magnetic recording medium 2; a spindle 3 and a spindle motor 4; a suspension arm 5; a voice coil motor 6; and a control unit 7. The control unit 7 has: a motor driver 8; a head amplifier 9; a read/write channel 10; a laser driver 11; and a controller 12. The controller 12 has: a preliminary recording unit 13; a judgment unit 14; an extraction unit 15; a drive condition determining unit 16; and a preliminary recording terminating unit 17. Based on a reproduction signal evaluation value obtained using these units and a predetermined reference value, a drive condition is determined which is suitable for recording onto the magnetic recording medium 2.

Abstract: Data storage systems are provided. Data storage systems illustratively include a recording head having a writing element and a bit patterned medium having a plurality of media dots. In some embodiments, the plurality of media dots pass the recording head at a media dot frequency. In some embodiments, the writing element writes data to the bit patterned media at a writing frequency that is less than the media dot frequency.

Abstract: A method includes writing data to a bit-patterned media at times determined by a clock having a period that is offset from a bit island period by a fixed offset to create one insertion or one deletion approximately within a predetermined number of bit islands, reading the data, and correcting the read data using error correction. An apparatus that implements the method is also provided.

Abstract: An apparatus and method are disclosed for writing data accumulated in a buffer on a tape medium in such a way that overwriting is prevented. The apparatus comprises a write unit configured for writing first data in a first position extending over a first track and an area adjacent to the first track, writing second data in a second position extending over a second track and an area adjacent to the second track, and writing the first data and the second data in a third position extending over a third track and an area adjacent to the third track. Furthermore, the apparatus comprises a processing unit configured for preventing the first data written in the first position from being overwritten with the second data written in the second position or with the first data written in the third position.

Abstract: A recording system controller according to one embodiment includes a controller capable of selecting a level of a current or voltage applied to a first writer during the creation of a magnetic transition based on a current in at least one nearby writer. A recording system controller according to another embodiment includes a controller capable of selecting a timing of a current change applied to a first writer based on a current in at least one nearby writer for compensating for an effect of crosstalk from the at least one nearby writer. A method according to yet another embodiment includes selecting a level of a current or voltage applied to a first writer or selecting a timing of a current change applied to the first writer based on a current in at least one nearby writer for compensating for an effect of crosstalk from the at least one nearby writer.

Abstract: Signal correction is performed by determining an offset error based at least in part on a first portion of a signal within a first amplitude range. The offset error is associated with error due to offset in the signal. An signal error, associated with error due to offset and magneto-resistive asymmetry (MRA) in the signal, is determined based at least in part on a second portion of the signal within a second amplitude range; the second amplitude range does not overlap with the first amplitude range. An MRA error is determined by removing the offset error from the signal error and the MRA error is removed from the signal.

Abstract: A data recording apparatus of the present invention includes a head that records data signals by magnetizing a magnetic tape 10 and a recording control portion that controls the recording operation by causing recording current to flow to the head. The recording control portion controls the operation of the head, so that in the magnetic tape 10, which is direct current demagnetized continuously in the longitudinal direction, a magnetic field is formed intermittently in an opposite direction to the magnetization direction of the direct current demagnetization. Thus, when recording data signals on the magnetic recording medium, it is possible to make the current flowing to the head small and to realize apparatus power consumption reductions, load reductions for the head and circuitry, and reduction in crosstalk noise from the head chip used for writing to the head chip used for reading.

Abstract: A method for compensating for tape deformation in a tape drive includes determining location of deformation on a tape; processing the tape in a first manner before and after the deformation; and processing the tape proximate the deformation in a second manner different than the first manner. The step of processing the tape in the first manner comprises recording data on the tape.

Abstract: A tape drive for use with a tape cartridge having a cartridge leader includes a drive body, and a drive leader that is engageable with the cartridge leader and moveable with respect to the drive body. The tape drive further includes an engaging member that is engageable with a first portion of the drive leader and moveable with respect to the drive body for connecting the drive leader with the cartridge leader of the tape cartridge. The tape drive also includes a retention feature that is engageable with a second portion of the drive leader for inhibiting disengagement of the drive leader from the engaging member, wherein the second portion of the drive leader is different than the first portion.

Abstract: A disk-drive magnetic circuit fixing structure and fixing method for fixing a magnetic circuit to a base by means of a plurality of screws, wherein provisions are made to substantially prevent a microscopic sliding movement involving impulsive vibration from occurring at a fastening portion between the magnetic circuit and the base. More specifically, in a disk drive including a disk enclosure having a base and a cover, a magnetic head contained within the disk enclosure, and a driving coil motor for driving the magnetic head by working in combination with an actuator on which the magnetic head is mounted and a magnetic circuit disposed in the vicinity of the actuator, the magnetic circuit is fixed to the base with a single or a plurality of screws by applying in advance a lubricant forming a lubricating layer on a face where each screw contacts the magnetic circuit or the base.

Abstract: A planar write module and a hybrid planar write-vertical read bidirectional tape head comprising the write module and one or more vertical read modules. The write module has a write module tape bearing surface for engaging the magnetic recording tape. Plural write elements in the write module each comprise plural thin film layers oriented in generally parallel planar relationship with the write module tape bearing surface. The write elements are arranged so that the transducing gaps (write gaps) of adjacent write elements are generally aligned in a direction that is transverse to a streaming direction of the magnetic recording tape. Each read module has a read module tape bearing surface for engaging the magnetic recording tape. Plural read elements in the one or more read modules each comprise plural thin film layers oriented in generally perpendicular relationship with the read module tape bearing surface.

Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.

Abstract: A suspension for a HGA includes a flexure having a tongue region and an outrigger. The outrigger has a pair of rigid beams and a pair of spring beams. The pair of spring beams enables the flexure to possess favorable flexibility and assists a slider to have enough displacement. The pair of rigid beams provides the flexure enough stiffness which not only successfully prevents the HGA with the outrigger from suspension deformation and dimple separation, but also assists to improve shock performance of the HGA. Furthermore, such configuration of the suspension provides the slider a good static performance and thus improves dynamic performance of the HGA. The present invention also discloses a HGA with the suspension, a manufacturing method of the HGA, and a drive unit with such an HGA.

Abstract: Embodiments of the present invention provide a suspension assembly having a dielectric limiter. According to one embodiment, the suspension assembly includes a load beam and a flexure assembly. The flexure assembly includes a metal layer where there are formed a fixing portion fixed to the load beam, main rings, and extending from the fixing portion, sub-rings, and a flexure tongue having moving-side limiter coupling portions defined thereon. Fixing-side limiter coupling portions are defined at the main rings. Dielectric limiters each have a gross length larger than a between-coupling-portions distance between a fixing-side limiter coupling portion and a moving-side limiter coupling portion, and couple the fixing-side limiter coupling portion to the moving-side limiter coupling portion.

Abstract: An integrated lead flexure includes traces with windowed or reduced width portions. The flexure includes a metal base layer with a plurality of apertures, an insulating layer on the metal base layer, and one or more conductive traces formed on the insulating layer and extending over the metal base layer and the plurality of apertures. Backed portions of the one or more conductive traces that extend over the metal base layer have a first width, and unbacked portions of the one or more conductive traces that extend over the plurality of apertures have a second width that is less than the first width.

Abstract: Embodiments of the present invention provide a magnetic disk device that can reduce an external force applied to the carriage. According to one embodiment, in a magnetic disk device, a bracket inserted between a carriage and a base is supported toward the base side by support portions owned by the bracket and by a band with a space provided between the bracket and the opposed side of the carriage (such as a top surface of the mounting stand). This configuration cannot apply an external force in the rotation direction to the carriage from the bracket even when the bracket is thermally expanded due to heat generated from a head amplifier or the like mounted on a flexible substrate.

Abstract: A multi-channel thin-film magnetic head includes a substrate, a plurality of MR read head elements, a plurality of first resistive elements, and a second resistive element. Each MR read head element includes a lower magnetic shield layer, an upper magnetic shield layer, and an MR layer arranged between the lower magnetic shield layer and the upper magnetic shield layer. Each first resistive element has a first resistance value. One ends of the first resistive elements are connected to the lower magnetic shield layers or the upper magnetic shield layers of the MR read head elements, respectively. The second resistive element has a second resistance value that is higher than the first resistance value. One end of the second resistive element is commonly connected to the other ends of the plurality of first resistive elements. The other end of the second resistive element is grounded.

Abstract: A TMR sensor structure having free and reference layers, where the magnetic orientations of the free and reference layers are non-orthogonal. In one embodiment, a ferromagnetic free layer film has a bias-point magnetization nominally oriented in plane of the film thereof, in a first direction at an angle ?fb with respect to a longitudinal axis being defined as the intersection of the plane of deposition of the free layer and the plane of the ABS. A ferromagnetic reference layer film has a bias-point magnetization nominally oriented in a plane of the film thereof, in a second direction at angle ?rb with respect to said longitudinal axis that is not orthogonal to the said first direction.

Abstract: The present invention relates to a method of manufacturing a DFL type thin film magnetic head. The method includes laminating each of the layers from the lower magnetization control layer to the upper exchange coupling layer above the substrate; laminating an auxiliary magnetization control layer including at least a CoZrTa layer above the upper exchange coupling layer; forming at least each of the layers from the lower exchange coupling layer to the auxiliary magnetization control layer in pillar shape, and disposing the bias magnetic field application layer at an opposite position with respect to the ABS of each of the pillar shaped layers; trimming the auxiliary magnetization control layer by removing a part of the auxiliary magnetization control layer that is formed in the pillar shape, and disposing the upper shield layer such that the trimmed auxiliary magnetization control layer is at least covered.

Abstract: A tunneling magnetic sensing element includes: a pinned magnetic layer whose direction of magnetization is pinned in one direction; an insulating barrier layer; and a free magnetic layer whose direction of magnetization changes in response to an external magnetic field. The pinned magnetic layer, the insulating barrier layer and the free magnetic layer are deposited in the named order. A first protective layer composed of a platinum-group element is disposed on the free magnetic layer, and a second protective layer composed of Ti is disposed on the first protective layer.