Abstract: This exposure method comprises a first step of performing the exposure processing by irradiating a projection optical system (the system) by a first pupil plane illumination distribution (the first distribution) of the system; a second step of performing the exposure processing by irradiating the system by a second pupil plane illumination distribution (the second distribution) that is different from the first distribution, after the first step; a change amount obtaining step of obtaining a change amount of an imaging performance of the system in a condition of the second distribution, with respect to the imaging performance in the first step; and a correction amount obtaining step of obtaining a correction amount for correcting the imaging performance in the second step, by using the change amount, wherein, in the second step, the exposure processing is performed by correcting the imaging performance using the correction amount.

Abstract: A pattern-forming method includes applying an inorganic film-forming composition on an upper face side of a substrate to provide an inorganic film, forming a resist pattern on an upper face side of the inorganic film; and dry-etching once or several times using the resist pattern as a mask such that the substrate has a pattern The inorganic film-forming composition includes a polyacid or a salt thereof, and an organic solvent. The step for forming a resist pattern may include the steps of: applying a resist composition on an upper face side of the inorganic film to provide a resist film; exposing the resist film; and developing the resist film exposed.

Abstract: A developing solution for a polyimide precursor containing N,N,N?,N?-tetramethylurea and a lower alcohol having 1 to 5 carbon atoms. The developing solution increases a development margin and results in little or no decrease of the film thickness of a polyimide-based resin film. A development processing method of a photosensitive polyimide resin composition including developing a photosensitive polyimide precursor resin composition, at least a part of which is exposed, with the developing solution; and a pattern formation method including forming a coating film or molding including a photosensitive polyimide precursor resin composition, selectively exposing the coating film or molding, and developing the exposed coating film or molding by the development processing method.

Abstract: A method of lithography patterning includes forming a resist layer over a substrate and providing a radiation with a first exposure dose to define an opening to be formed in the resist layer. The opening is to have a target critical dimension CD1 after developed by a negativ-tone development (NTD) process. The method further includes exposing the resist layer to the radiation with a second exposure dose less than the first exposure dose and developing the resist layer in a negative-tone development process to remove unexposed portions of the resist layer, resulting in an opening between resist patterns. A critical dimension CD2 of the opening is greater than CD1 by a delta. The method further includes forming an interfacial layer on sidewalls of the resist patterns. The interfacial layer has a thickness that is substantially equal to half of the delta.

Abstract: A light transmission device is provided. The light transmission device includes a light source, a light transmission module and at least one light regulator. The light transmission module transmits a portion of the light of the light source for implementing a first semiconductor manufacturing process over the wafer. The light source is utilized to implement a second semiconductor manufacturing process over a wafer. The first semiconductor manufacturing process is different from the second semiconductor manufacturing process. The at least one light regulator regulates the light of the light transmission module transmitted to the wafer.

Abstract: An illumination optical unit comprises a first faceted element and a second faceted element having a multiplicity of displaceable micromirrors which can be grouped flexibly to form facets.

Abstract: In corner sections of first to fourth quadrants whose origin point is a center of an upper surface of a stage, three each of two-dimensional heads are provided. The three each of two-dimensional heads include one first head and two second heads. The stage is driven, while measuring a position of the stage using three first heads that face a two-dimensional grating of a scale plate provided above the stage from the four first heads, and during the driving, difference data of measurement values of the two second heads with respect to the first head in a measurement direction are taken in for head groups to which the three first heads belong, respectively, and using the difference data, grid errors are calibrated.

Abstract: A slit shaped area of a patterning device is illuminated to impart a radiation beam with a pattern in its cross-section. A projection system projects the patterned radiation beam onto a target portion of a substrate. As the radiation beam is scanned across the target portion of the substrate, a configuration of the projection system is adjusted and applies a pattern to the target portion. The adjusting may affect a magnitude of an image magnification component of the projection system, along the length of the slit shaped area, or an image distortion in a scan direction. The adjusting is arranged to compensate an effect on pattern overlay accuracy of a distortion of the patterning device.

Abstract: A conjugate common light path lithography lens set includes a first, second, third, and fourth spherical mirrors, arranged sequentially, a spherical reflecting mirror arranged below the fourth spherical mirror, a first and second planar reflecting mirrors, inclinedly arranged above the first spherical mirror, so that a conjugate telecentric component pattern is formed to maintain an pattern of an object to have a non-deformed pattern after experiencing these optical components. As such, the omni-spherical mirror set and two kinds of optical material are mutually arranged to form the novel conjugate common light path lithography lens set. This may further achieve the function of the lithography lens, and have a direct effect on the manufacturing cost.

Abstract: Optical modules used in exposure processes, in particular to optical modules of microlithography systems, are disclosed. Methods for deforming an optical element of an optical module as well as to optical imaging arrangements, optical imaging of methods and a method of manufacturing an optical element, are also disclosed. The disclosed technology may be used in the context of photolithography processes for fabricating microelectronic devices, in particular semiconductor devices, or in the context of fabricating devices, such as masks or reticles, used during such photolithography processes.

Abstract: An optical projection unit includes first and second optical element modules. The first optical element module includes a first housing unit and a first optical element received within the first housing unit and having an optically used first region defining a first optical axis. The second optical element module is located adjacent to the first optical element module and includes a second optical element which defines a second optical axis of the optical projection unit. The first housing unit has a central first housing axis and an outer wall extending in a circumferential direction about the first housing axis. The first optical axis is laterally offset and/or inclined with respect to the first housing axis. The first housing axis is substantially collinear with the second optical axis.

Abstract: An super-resolution system for nano-patterning is disclosed, comprising an optical printing head that enables a super-resolution lithographic exposures compatible with conventional optical lithographic processes. The super-resolution exposures are carried out using light directed onto a medium using plasmonic structures, and in particular using plasmonic structures using specially designed super-resolution apertures, of which the “bow-tie” and “C-aperture” are examples. These specially designed apertures create small but bright images in the near-field transmission pattern. A printing head comprising an array of these apertures is held in close proximity to a medium for patterning. In some embodiments, a data processing system is provided to re-interpret the data to be patterned into a set of modulation signals used to drive the multiple individual channels and the multiple exposures.

Abstract: Maskless lithographic apparatus measuring accumulated amount of light is provided. The maskless lithographic apparatus includes a light source which emits light, a stage on which a substrate is disposed, an optical system which converts the light into a beam spot array including a plurality of columns and a plurality of rows and irradiates the beam spot array onto the stage, a slit to which the beam spot array is irradiated and which passes an nth (n is a natural number) row of the beam spot array, an optical sensor which senses the nth row of the beam spot array which has passed through the slit, and a measuring unit which measures an accumulated amount of light in the nth row of the beam spot array sensed by the optical sensor.

Abstract: Methods and systems for determining a process window for a process performed on a specimen are provided. In general, the embodiments preferentially sample locations in an instance of at least a portion of a device formed on a specimen at a value of a parameter of a process performed on the specimen that is closest to an edge of a determined process window for the process. If defects are detected at the sampled locations, then the sampling may be performed again but for a different instance of the device formed at a value of the parameter that is closer to nominal than the previously used value. When no defects are detected at the sampled locations, then the sampling may be ended, and the determined process window may be modified based on the value of the parameter corresponding to the instance of the device in which no defects were detected.

Abstract: An immersion projection optical system having, for example, a catadioptric and off-axis structure, reduces the portion of an image space filled with liquid (immersion 5 liquid), The projection optical system, which projects a reduced image of a first plane onto a second plane through the liquid, includes a refractive optical element (Lp) arranged nearest to the second plane. The refractive optical element includes a light emitting surface (Lpb) shaped to be substantially symmetric with respect to two axial directions (XY·axes) perpendicular to each other on the second plane. The light emitting surface has a central axis (Lpba) that substantially coincides with a central axis (40a) of a circle (40) corresponding to a circumference of a light entering surface (Lpa) of the refractive optical element. The central axis of the light emitting surface is decentered in one of the two axial directions (Y˜axis) from an optical axis (AX).

Abstract: A measurement apparatus including an optical system to provide illumination radiation into a spot on a periodic structure and to receive radiation redirected by the periodic structure, the optical system including a first stop to block zero order radiation from the periodic structure and allow non-zero order radiation to pass, and a second stop to block zero order radiation passing the first stop and to allow the non-zero order radiation to pass, and a radiation detector, downstream of the optical system, to receive the non-zero order radiation.

Abstract: A thermal conditioning unit to thermally condition a substrate, the thermal conditioning unit including: a thermal conditioning element having a first layer, in use, facing the substrate and including a material having a thermal conductivity of 100 W/mK or more, a second layer and a heat transfer component positioned between the first and second layers; and a stiffening member which is stiffer than the thermal conditioning element and configured to support the thermal conditioning element so as to reduce mechanical deformation thereof, wherein the thermal conditioning element is thermally isolated from the stiffening member.

Abstract: A lithographic apparatus having a first outlet to provide a thermally conditioned fluid with a first flow characteristic to at least part of a sensor beam path, and a second outlet associated with the first outlet and to provide a thermally conditioned fluid with a second flow characteristic, different to the first flow characteristic, adjacent the thermally conditioned fluid from the first outlet.

Abstract: An electrostatic charge image developing toner includes toner particles and an external additive that includes silica particles having a compression aggregation degree of 60% to 95% and a particle compression ratio of 0.20 to 0.40 and fatty acid metal salt particles.

Abstract: Disclosed herein include toner compositions with toner particles having a core-shell type structure, where the core comprises a first resin comprising a styrene-acrylate copolymer and an amorphous polyester resin, and the shell comprises a second resin comprising beta-carboxyethyl acrylate (b-CEA) in an amount of from about 0.05 pph to about 2.5 pph by weight of the second resin.

Abstract: An electrostatic charge image developer includes a toner that includes a toner particle; and a carrier, wherein the toner particle contains a brilliant pigment, an exposed amount of the brilliant pigment contained in the toner particle is from 0.5% to 5%, the carrier has a core particle and a coating layer which covers a surface of the core particle, the coating layer contains a silicone resin and a siloxane oligomer, and a content of the siloxane oligomer is from 0.1 ppm to 500 ppm with respect to a total weight of the coating layer.

Abstract: An ultraviolet-curable liquid developer containing a cationically polymerizable liquid monomer, a photoinitiator according to formula (1), and a toner particle. In the developer the cationically polymerizable liquid monomer contains a vinyl ether compound, the molar average SP value of the cationically polymerizable liquid monomer is not more than 9.0, the molar average number of functional groups for the cationically polymerizable liquid monomer is at least 1.8, the photoinitiator contains a specified compound, and the content of the specified compound is at least 0.01 mass parts and not more than 5.00 mass parts per 100 mass parts of the cationically polymerizable liquid monomer.

Abstract: Provided is a ultraviolet-curable liquid developer containing a toner particle, a cationically polymerizable liquid monomer, and a photoinitiator that contains a compound according to formula (1): The cationically polymerizable liquid monomer contains a vinyl ether compound satisfying A/B×1,000?8.5, wherein A is the molar average number of functional groups for the vinyl ether compound and B is the molar average molecular weight of the vinyl ether compound.

Abstract: An image forming method is provided. The method includes the steps of forming an electrostatic latent image on a photoconductor; developing the electrostatic latent image into a toner image with a toner; transferring the toner image onto a recording medium having a smoothness of 20 s or less; and fixing the toner image on the recording medium. The toner exhibits an adhesion force of 100 gf or more, where the adhesion force is the maximum value of a pull force between a layer of the toner and standard paper determined by a tacking test with a probe temperature of 140° C.

Abstract: A light scanning apparatus, including: a light source configured to emit a light beam; a rotary polygon mirror configured to deflect the light beam emitted from the light source so that the light beam scans on a surface of a photosensitive member in a main scanning direction; a motor configured to rotate the rotary polygon mirror; and a rotational position detection unit configured to detect a magnetic flux change caused by rotation of the motor to generate a rotational position detection signal, wherein an emitting start timing of the light beam from the light source is determined based on the rotational position detection signal in order to maintain a writing start position of the light beam with respect to the photosensitive member in the main scanning direction.

Abstract: A developing device is equipped with a developing roller rotationally driven for developing an electrostatic latent image formed on a surface of an image supporting body with toner, a screw rotationally driven of which a ratio of number of rotations to number of rotations of the developing roller being rotationally driven is constant, and a processor. The processor is configured to detect toner density in developer by using a sensor installed facing the screw, during rotationally drive of the screw, and detect information indicating a rotational position of the developing roller, based on ripples which occur in the toner density detected.

Abstract: A roller member used in an image forming apparatus includes a metallic shaft, and the metallic shaft includes a cylindrical portion formed of a metallic plate, and a projecting portion projecting outward from end surfaces of the cylindrical portion, wherein end portions of the metallic plate each include a straight portion, projections, and depressions, the projections on the one end portion engage the depressions on the other end portion, the depressions on the one end portion engage the projections on the other end portion, and the straight portions on both end portions oppose each other, a straight area is positioned on an end portion of the cylindrical portion, a projection and depression area is located adjacent to the straight area, and a projecting amount of the projection with respect to the straight portion is smaller than a projecting amount of the projection with respect to the depression.

Abstract: The image forming apparatus prevents a transfer roller from slipping when discharge processing for supplying toner to a contact portion between a photosensitive drum and a cleaning blade is performed. The developing unit performs transfer operation to form band-like toner images on a photosensitive drum to supply a predetermined amount of toner to a contact portion between the photosensitive drum and a cleaning blade without causing the transfer roller to perform transfer operation, so that the predetermined amount of toner is supplied in a plurality of batches.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a sensor. The processing circuitry counts the number of the pulses received from the sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the sensor and resets the count of the pulses received from the sensor.

Abstract: A developing device includes a container chamber that contains developer containing carrier and toner; a supply portion that is adjacent to the container chamber and to which supplying toner or supplying developer, which contains the supplying toner and supplying carrier, is supplied at a supplying position in the supply portion; a transporting member that transports the supplying toner or the supplying developer toward the container chamber in the supply portion; and a guide capable of guiding the developer to the supplying position.

Abstract: An electrostatic charge image developing toner set includes a brilliant toner including toner particles that include a brilliant pigment and a first binder resin, a black toner including toner particles that include a second binder resin, and a color toner except a black toner, including toner particles that include a third binder resin, wherein the brilliant toner, the black toner and the color toner satisfy Expression (1): Dielectric loss factor of the brilliant Toner>Dielectric loss factor of the black toner>Dielectric loss factor of the color toner and Expression (2): 25×10?3?(Dielectric loss factor of the brilliant toner)?(Dielectric loss factor of the color toner)?95×10?3.

Abstract: A wet type developing device including a developing roller and an anilox roller, the wet type developing device includes: a dual purpose roller being opposite to the surface of the anilox roller, leaving a gap therebetween, upstream of a region of contact between the surfaces of the anilox roller and the developing roller and being in contact with the surface of the developing roller upstream of the region of contact between the surfaces of the anilox roller and the developing roller and being rotationally driven. A surface part of the dual purpose roller is made of a porous member that has flexibility and elasticity.

Abstract: An image formation apparatus includes: an intermediate transfer belt that carries and conveys a developer image formed by an image formation section; a driver that conveys the intermediate transfer belt in a predetermined direction; a transfer device that transfers the developer image carried on the intermediate transfer belt onto a predetermined medium; a first detector that detects a belt conveyance speed, which is the speed of the intermediate transfer belt conveyed; a controller that controls the driver; a conveyer section that conveys the medium to the transfer device; and a second detector that detects a medium conveyance speed, which is the speed of the medium conveyed by the conveyer section. The controller controls driving of the driver on the basis of the belt conveyance speed and the medium conveyance speed.

Abstract: A semiconductive resin composition includes a plurality of thermoplastic resins forming a sea-island structure including a sea portion and an island portion; and a plurality of conductive fillers. The sea portion includes at least two of the thermoplastic resins, at least one of the at least two of the thermoplastic resins is a copolymer, and the content of the copolymer is from 20% to 60% by weight per 100% by weight of the thermoplastic resins in the sea portion, and the following relation is satisfied: 1.5?B/A?10 wherein A represents an average primary particle diameter of one of the conductive fillers having the smallest average primary particle diameter and B represents an average primary particle diameter of one of the conductive fillers having the largest average primary particle diameter.

Abstract: Certain embodiments provide a transfer apparatus, which including: an conductive intermediate transfer member; a transfer section configured to secondarily transfer a toner image onto an image receiving medium in a constant current system; a conveyance section configured to convey the image receiving medium; and a high voltage transformer configured to apply a bias to the transfer member, wherein the sum of the products of the volume resistivities [?·cm] and the thicknesses [cm] of the intermediate transfer member and the transfer member is equal to or greater than 3.6×108 ?·cm2, and the conveyance speed V[mm/s] of the image receiving medium={the output upper limit value A[V] of the absolute value of the voltage output from the transfer polarity side of the high voltage transformer}×0.009.

Abstract: An image forming apparatus includes an image bearer; a transfer rotator to contact the image bearer to form a transfer nip therebetween; a bias application device to apply, to the transfer rotator, a transfer bias, a cleaning bias to remove toner adhering to the transfer rotator, and a non-image area bias smaller in absolute value than the cleaning bias; and a controller to control the bias application device and set a sheet feeding interval according to a predetermined condition. When the sheet feeding interval exceeds a predetermined threshold, the controller causes the bias application device to apply, to the transfer rotator, the non-image area bias for an application time Z and the cleaning bias for a time X?Z within the sheet feeding interval when X represents the sheet feeding interval, and the application time Z is increased as the sheet feeding interval is increased.

Abstract: An image forming device that forms an image by transferring a toner image formed by developing an electrostatic latent image formed on a photoreceptor from the photoreceptor to an intermediate transfer body by applying a transfer bias to a transfer member and putting the transfer member in contact with the intermediate transfer body. The device includes: a current supplier selectively supplying a first constant current and a second constant current to the transfer member; a first voltage acquirer acquiring a first voltage occurring between the transfer member and the intermediate transfer body while the transfer member is supplied with the first constant current; a second voltage acquirer acquiring a second voltage occurring between the transfer member and the photoreceptor while the transfer member is supplied with the second constant current; and a thickness acquirer acquiring a value indicating photoreceptor layer thickness of the photoreceptor by using the first and second voltages.

Abstract: An image forming apparatus includes: a fixing section configured to fix a toner image formed on a recording medium to the recording medium by conveying the recording medium while heating and pressing the recording medium at a fixing nip; a conveyance section configured to convey the recording medium toward the fixing nip while sandwiching the recording medium; and a control section configured to control the fixing section such that, at a timing after an image formation operation on the recording medium is stopped during the image formation operation, conveyance of the recording medium in the fixing section is stopped before the conveyance of the recording medium in the conveyance section is stopped, and that a timing of stopping the conveyance of the recording medium in the fixing section is changed in accordance with a type of the recording medium.

Abstract: According to one embodiment, a fixing device includes a heat roller, a heat generating body, and a controller. The heat roller heats a conveyed sheet. The heat generating body generates heat with electric power in the heat roller. The controller applies thinning control to electric energy supplied to the heat generating body in processing for heating the heat roller.

Abstract: The present invention is directed to providing a fixing member that can form high quality electrophotographic images. The fixing member includes a substrate, an elastic layer on the substrate and a surface layer bonded to the elastic layer with an adhesive layer. The surface layer contains a fluorine resin. The surface layer having a thermal resistance in the thickness direction of 3.0×10?5 m2·K/W or more and 1.3×10?4 m2·K/W or less and the peel adhesion strength between the surface layer and the elastic layer is 3.0 N/cm or more and 20.0 N/cm or less, while the elastic layer undergoes a cohesive failure in a peel test between the surface layer and the elastic layer and the fluorine resin contains a tetrafluoroethylene/perfluoroethyl vinyl ether copolymer, the polymerization ratio of perfluoroethyl vinyl ether in the copolymer being 3.0 mol % or more and 5.8 mol % or less.

Abstract: A fixing device according to an embodiment includes a first rotating body, a pressing unit, an urging member, a base body section, a screw shaft section, and a rotation regulating section. The pressing unit includes a belt, a second rotating body, and a supporting frame. The supporting frame supports the second rotating body. The urging member urges the pressing unit in a direction in which the second rotating body approaches the first rotating body. The base body section is rotatable around an axis. The shape of a cross section of the base body section orthogonal to an axial direction is a noncircular shape. The screw shaft section projects from the base body section and regulates a movement of the pressing unit in a direction in which the pressing unit approaches the first rotating body. The rotation regulating section comes into contact with the outer surface of the base body section to regulate the rotation of the base body section.

Abstract: An embodiment of an image forming apparatus includes a first image forming unit including a photosensitive drum and a fur brush for cleaning toner on the photosensitive drum and a second image forming unit including a photosensitive drum and a fur brush for cleaning toner on the photosensitive drum. In at least one embodiment for image formation, the fur brush in the first image forming unit and the fur brush in the second image forming unit start at different timings.

Abstract: An image forming system includes: a sheet feeding unit configured to feed continuous paper into an image forming unit; a winding unit configured to wind up the continuous paper; the image forming unit configured to perform image formation on the continuous paper being conveyed from the sheet feeding unit to the winding unit; and a processor configured to perform control to form a proof image in a second job immediately after completion of a first job and put the second job into a standby state, when a setting is made for formation of the proof image for checking a predetermined page in the second job after completion of the first job but before execution of the second job.

Abstract: There are included an image forming unit for forming an image on continuous paper, a continuous paper conveying unit for conveying the continuous paper, and a control unit for controlling the image forming unit and the continuous paper conveying unit, wherein, after conveyance is started by the continuous paper conveying unit in printing preparation and before printing is started, the control unit is enabled to perform meandering prevention approach control of stabilizing conveyance of continuous paper that is being conveyed, and allows switching between performance and non-performance of the meandering prevention approach control and/or changing a level of the meandering prevention approach.

Abstract: A post-processing device includes a processing stacking portion that allows media to be stacked thereon; a binding member that performs a binding process on the media; a medium ejection portion on which the media ejected from the processing stacking portion are stacked and which moves upward and downward; and a pressing member that presses an upper surface of the media on the medium ejection portion. When media that have not been subjected to the binding process are stacked on the medium ejection portion, the pressing member and the media are brought into contact with each other. When media that have been subjected to the binding process are stacked on the medium ejection portion, the pressing member and the media are disposed further away from each other than when media that have not been subjected to the binding process are stacked on the medium ejection portion.

Abstract: A paper humidifying apparatus includes humidifying rollers, a first drive unit and a controller. The humidifying rollers, forming a pair, are pressed against each other forming a nip portion and apply moisture to a sheet of paper when sandwiching and conveying the sheet of paper. The first drive unit which makes the humidifying rollers separate from each other or press against each other. The controller controls the first drive unit. The controller controls the first drive unit so as to make the humidifying rollers separate from each other and receive the sheet of paper, and after a tip of the sheet of paper passes a position corresponding to the nip portion, the controller controls the first drive unit so as to make the humidifying rollers press against each other to apply moisture to the sheet of paper.

Abstract: An image forming apparatus according to an embodiment comprises a first image forming section configured to form an image on a recording medium with a non-erasable material, and a second image forming section configured to form an image on the recording medium with an erasable material. The image forming apparatus further comprises a control section configured to separate image data according to attributes of the image data into first image data to be printed on the recording medium in the first image forming section and second image data to be printed on the recording medium in the second image forming section.

Abstract: A high-voltage power supply that outputs high voltages having a predetermined polarity and a reverse polarity performs control in a manner that, during a transition period in which switching of a target voltage of the high voltage having the reverse polarity from the predetermined polarity is performed, a setting value in accordance with a voltage higher than a target voltage is set as the voltage having the reverse polarity, and then a setting value in accordance with the target voltage is set as the voltage having the reverse polarity.

Abstract: An image forming device includes an attachment part to which a toner unit having a fuse that can be molten by being supplied with an electric current is detachably attached, and a control part that applies each of a non-melting conduction signal corresponding to a first current supply state where the fuse is not molten and a melting conduction signal corresponding to a second current supply state where the fuse is molten to the fuse. The control part detects each of whether or not the fuse is molten by applying the non-melting conduction signal and whether or not the fuse is molten by applying the melting conduction signal. The control part determines whether or not the toner unit attached to the attachment part is a specific exchange unit on the basis of a detection result of whether or not the fuse is molten.

Abstract: A developer feeding device includes a cleaning member contacted to an image bearing drum; a accommodating portion for the developer removed by the cleaning member; a feeding member for feeding the developer from the accommodating portion; a sheet contacted to the drum; and a guide forming a part of a wall surface of the accommodating portion at a position in a side of the sheet with respect to a line connecting a drum center and a feeding member center, as seen in a drum axis direction. The guide extends in a acute angle range formed between a first line extending vertically through the feeding member center and a second line extending in a direction of a rest angle of the developer through the feeding member center, the guide having a shape such as to approach to a linear shape as a distance of the feeding member decreases.