Abstract: A lithographic apparatus comprises a projection system comprising position sensors to measure a position of optical elements of the projection system. The positions sensors are referenced to a sensor frame. Damping actuators damp vibrations of the sensor frame. A control device drives the actuators and is configured to derive sensor frame damping force signals from at least one of the acceleration signals and the sensor frame position signals, derive an estimated line of sight error from the position signals, determine actuator drive signals from the sensor frame damping force signals and the estimated line of sight error, drive the actuators using the actuator drive signals to dampen the sensor frame and to at least partly compensate the estimated line of sight error.

Abstract: An overlay correcting method capable of optimizing correction of an overlay within a scanner correction limit of a scanner of a scanner system, and a photolithography method, a semiconductor device manufacturing method and the scanner system which are based on the overlay correcting method are provided. The overlay correcting method includes collecting overlay data by measuring an overlay of a pattern; calculating correction parameters of the overlay by performing regularized regression using the overlay data, the regularized regression being based on a correction limit of the scanner such that the correction parameters fall within the correction limit of the scanner; and providing the correction parameters to the scanner.

Abstract: Semiconductor device packages and associated methods are disclosed herein. In some embodiments, the semiconductor device package includes (1) a first surface and a second surface opposite the first surface; (2) a semiconductor die positioned between the first and second surfaces; and (3) an indication positioned in a designated area of the first surface. The indication includes a code presenting information for operating the semiconductor die. The code is configured to be read by an indication scanner coupled to a controller.

Abstract: A reflective member is disposed on the optical path from the linear light source to the lens array. An ultraviolet light blocking filter is provided closer to a light-receiving unit than the reflective member. A color filter is provided closer to the light-receiving unit than the ultraviolet light blocking filter. A light-receiving surface of the light-receiving unit has a first region opposed to the reflective member without the ultraviolet light blocking filter and the color filter interposed therebetween, a second region opposed to the reflective member and the ultraviolet light blocking filter without the color filter interposed therebetween, and a third region opposed to the reflective member, the ultraviolet light blocking filter, and the color filter.

Abstract: A model-based tuning method for tuning a first lithography system utilizing a reference lithography system, each of which has tunable parameters for controlling imaging performance. The method includes the steps of defining a test pattern and an imaging model; imaging the test pattern utilizing the reference lithography system and measuring the imaging results; imaging the test pattern utilizing the first lithography system and measuring the imaging results; calibrating the imaging model utilizing the imaging results corresponding to the reference lithography system, where the calibrated imaging model has a first set of parameter values; tuning the calibrated imaging model utilizing the imaging results corresponding to the first lithography system, where the tuned calibrated model has a second set of parameter values; and adjusting the parameters of the first lithography system based on a difference between the first set of parameter values and the second set of parameter values.

Abstract: An image forming apparatus includes a rotatable photosensitive member. A charging member charges a surface of the photosensitive member. A developing roller carries developer. The developing roller supplies the developer in normal polarity to the surface of the photosensitive member. A regulating member regulates the developer on the developing roller. A common voltage applying unit applies charging voltage and regulating voltage. The regulating voltage is applied with the developing roller rotating such that a potential difference in a direction in which electrostatic force from the regulating member to the developing roller acts on the developer charged in the normal polarity, is formed between the regulating member and the developing roller, and in which the charging voltage to be applied in a non-image-forming period is controlled so as to be smaller in absolute value than in an image-forming period.

Abstract: Methods and apparatuses for determining a position of an alignment mark applied to a region of a first layer on a substrate using a lithographic process by: obtaining an expected position of the alignment mark; obtaining a geometrical deformation of the region due to a control action correcting the lithographic process; obtaining a translation of the alignment mark due to the geometrical deformation; and determining the position of the alignment mark based on the expected position and the translation.

Abstract: Provided is a charged particle beam device capable of making a time lag as small as possible when transporting a succeeding wafer from an FOUP to an SC in parallel with returning a preceding wafer from a sample chamber to the FOUP. The charged particle beam device according to the disclosure predicts a completion time point at which a recipe of the preceding wafer is ended, and sets a time point at which the succeeding wafer is started to be taken out from the FOUP so that a timing at which the succeeding wafer is taken out from the FOUP to a load lock chamber and vacuum evacuation of the load lock chamber is completed matches the completion time point.

Abstract: A substrate inspection method includes: acquiring a feature amount of each of divided areas in an inspection target peripheral edge image, the inspection target peripheral edge image being an image of a peripheral portion of a target substrate as an inspection target, the divided areas being obtained by dividing a predetermined area in the image of the peripheral portion of the target substrate into a plurality of areas; and performing a predetermined determination concerning inspection of the peripheral portion of the target substrate based on an acquisition result in the acquiring the feature amount.

Abstract: A detection method for a pellicle membrane of a photomask includes applying a predetermined pressure under which the pellicle membrane undergoes a deformation, measuring and calculating at least one of deformation level, Young's modulus, and flexural rigidity level of the pellicle membrane by detection, and obtaining a detection result about the pellicle membrane according to at least one of the deformation level, Young's modulus, and flexural rigidity level of the pellicle membrane, so as to evaluate the quality of the pellicle membrane.

Abstract: A three-dimensional printing system for fabricating a three-dimensional article includes a motorized build platform, a dispensing module, a pulsed light source, an imaging module, a movement mechanism, and a controller. The imaging module receives radiation from the pulsed light source and includes a two-dimensional mirror array. The movement mechanism imparts lateral motion between the imaging module and the build platform. The controller is configured to operate the motorized build platform and the dispensing module to form a layer of build material at a build plane, operate the movement mechanism to laterally scan the imaging module over the build plane, operate the pulsed light source to generate a sequence of radiation pulses that illuminate the mirror array, and operate the mirror array to selectively image the build material.

Abstract: A surgical microscope system for use in a medical procedure. The surgical microscope system is controlled in a first mode of operation corresponding to a phase of the medical procedure and defining at least one setting for adjusting a set of adjustable optics. While in the first mode of operation, the surgical microscope system automatically determines, from a captured image, an indication that a second mode of operation is relevant. The mode of operation is switched to the second mode of operation.

Abstract: A circuit board structure includes a circuit board body having an adsorption surface; an auxiliary board on which a binding mark is disposed. The auxiliary board is spliced to the circuit board body, and a surface of the auxiliary board is flush with the adsorption surface. A part of the adsorption surface and a part of the surface of the auxiliary board together form an adsorption zone.

Abstract: A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.

Abstract: An erasing unit according to an embodiment of the present disclosure is a unit that performs erasing of information written on a reversible recording medium. This erasing unit includes: a light source section including one or a plurality of laser devices; and a controller that controls the light source section to cause the light source section to emit a smaller number of laser light beams having emission wavelengths than the number of the recording layers included in the reversible recording medium.

Abstract: For the purposes of positioning a component part, provision is made in an optical system for a stray magnetic field to be detected via a sensor device and for a correction signal for compensating the effect of the stray magnetic field on the positioning of the component part to be ascertained.

Abstract: A method for forming a photo-mask includes providing a first pattern, wherein the first pattern includes a first light-transmitting region and a first light-shielding region; transforming the first pattern into a second pattern, wherein the second pattern includes a second light-transmitting region and a second light-shielding region, the second light-transmitting region is located within range of the first light-transmitting region, and the second light-transmitting region has an area which is smaller than that of the first light-transmitting region, the second light-shielding region includes the entire region of the first light-shielding region, and the second light-shielding region has an area which is greater than that of the first light-shielding region; and forming the second pattern on a photo-mask substrate to form a photo-mask, wherein the photo-mask is used in an ion implantation process of a material layer.

Abstract: The present invention discloses a digital photolithography method for a fiber optic device (FOD) based on a DMD combination. In this method, reflected light modulated by two DMDs is simultaneously projected onto a same position on an optical fiber end surface through one reduction projection lens. The two DMDs form a primary and secondary digital mask for joint control of an exposure dose distribution formed when patterns are shrunk and projected onto the optical fiber end surface. After the optical fiber end surface coated with photoresist is subject to this dose of exposure, developing, fixing, and etching are conducted, to form a micro-optic device on the optical fiber end surface. In the present invention, distribution of the exposure dose jointly modulated by a digital mask combination formed by the primary and secondary DMD exceeds an order of modulation of an exposure dose by a single DMD.

Abstract: A calibration method of a variable-focal-length lens including a liquid lens unit whose focal-length is periodically varied in response to a periodic drive-signal includes: using a calibration tool having a plurality of height-different parts on a surface; preparing a calibration table by repeating outputting a drive-signal having a predetermined voltage to the variable-focal-length lens, detecting a surface image of the calibration tool using an image detector, detecting two points having maximum image contrast in the surface image, calculating a focal-depth from a difference in a focal-length between the two points; and recording the focal-depth and the voltage of the drive-signal in a corresponding combination, and retrieving a value of the voltage corresponding to a desired focal-depth from the calibration table to set the variable-focal-length lens at the desired focal-depth, and adjusting the voltage of the drive-signal outputted to the variable-focal-length lens based on the retrieved value.

Abstract: Methods and systems for more efficient X-Ray scatterometry measurements of on-device structures are presented herein. X-Ray scatterometry measurements of one or more structures over a measurement area includes a decomposition of the one or more structures into a plurality of sub-structures, a decomposition of the measurement area into a plurality of sub-areas, or both. The decomposed structures, measurement areas, or both, are independently simulated. The scattering contributions of each of the independently simulated decomposed structures are combined to simulate the actual scattering of the measured structures within the measurement area. In a further aspect, measured intensities and modelled intensities including one or more incidental structures are employed to perform measurement of structures of interest. In other further aspects, measurement decomposition is employed to train a measurement model and to optimize a measurement recipe for a particular measurement application.

Abstract: A sensor mark including: a substrate having: a deep ultra violet (DUV) radiation absorbing layer including a first material which substantially absorbs DUV radiation; and a protecting layer including a second material, wherein: the DUV radiation absorbing layer has a through hole in it; the protecting layer is positioned, in plan, in the through hole and the protecting layer in the through hole has a patterned region having a plurality of through holes; and the second material is more noble than the first material.

Abstract: A method of measuring misregistration in the manufacture of semiconductor devices including providing a multilayered semiconductor device, using a scatterometry metrology tool to perform misregistration measurements at multiple sites on the multilayered semiconductor device, receiving raw misregistration data for each of the misregistration measurements, thereafter providing filtered misregistration data by removing outlying raw misregistration data points from the raw misregistration data for each of the misregistration measurements, using the filtered misregistration data to model misregistration for the multilayered semiconductor device, calculating correctables from the modeled misregistration for the multilayered semiconductor device, providing the correctables to the scatterometry metrology tool, thereafter recalibrating the scatterometry metrology tool based on the correctables and measuring misregistration using the scatterometry metrology tool following the recalibration.

Abstract: A display system capable of displaying appropriate information on a controller that performs control on an industrial machine including at least a machine tool or a robot on an external terminal is provided. A numerical controller of a display system includes a display data transmitting unit that transmits display data including a screen data ID of all pieces of data displayed on a touch panel to an external terminal. The external terminal includes: a description information storage unit that stores the screen data ID and description information in correlation; and a description information output unit that acquires, from the description information storage unit, description information based on the screen data ID included in the display data received from the numerical controller and outputs the description information to a touch panel.

Abstract: One or more embodiments are directed to cap attach trays for holding barrel caps such that a pick-and-place tool can readily identify the cap and pick the barrel cap from the cap attach tray during the manufacturing process. The cap attach trays include a receiving layer having a plurality of protrusions each of which secures a barrel cap by mating to a through-hole in the barrel cap.

Abstract: A 3D printing method for binary stereolithography 3D printer includes following steps of: controlling a binary stereolithography 3D printer (20) to retrieve a plurality of gray-scale slice images (802,822,842); mapping a pixel value of each pixel of each gray-scale slice images (802,822,842) from a pixel value full range to an accumulation value range for obtaining a printing parameter of each pixel; selecting one of the gray-scale slice images (802,822,842) orderly; controlling a binary lighting module (204) of the binary stereolithography 3D printer (20) to irradiate for generating a layer of physical slice model (320,322,340,342) according to the printing parameter of each pixel of the selected gray-scale slice image (802,822,842); and repeatedly executing aforementioned steps to generate a physical 3D model (8?) constituted by a stack of multiple of the physical slice models (320,322,340,342).

Abstract: Micro- and nano-patterns in imprint layers formed on a substrate and lithographic methods for forming such layers. The layers include a plurality of structures, and a residual layer having a residual layer thickness (RLT) that extends from the surface of the substrate to a base of the structures, where the RLT varies across the surface of the substrate according to a predefined pattern.

Abstract: A chirped radio frequency signal is transmitted across an area of a potential threat. A reflected radio frequency return signal from an open barrel of a weapon at a location within the area of the potential threat is received at an incident angle through an aperture. An antenna at a position in an antenna array detects the reflected radio frequency return signal received at the incident angle through the aperture. The position of the antenna within the antenna array corresponds to a direction from which the reflected radio frequency return signal originates.

Abstract: The present invention is to provide a liquid crystal display device which is capable of suppressing reflected glare of a display screen on a windshield and the like, has excellent front contrast, and has excellent visibility of a display screen as viewed via polarized sunglasses. A liquid crystal display device includes, in order from a viewing side, a viewing side polarizer, a liquid crystal cell, a non-viewing side polarizer, and an anisotropic light absorption layer having an absorption axis in a thickness direction. The liquid crystal display device further includes at least one polarization control layer, in which the polarization control layer is arranged on a viewing side of the viewing side polarizer or on a non-viewing side of the non-viewing side polarizer.

Abstract: Methods and systems for aligning images for a specimen acquired with different modalities are provided. One method includes acquiring information for a specimen that includes at least first and second images for the specimen. The first image is acquired with a first modality different than a second modality used to acquire the second image. The method also includes inputting the information into a learning based model. The learning based model is included in one or more components executed by one or more computer systems. The learning based model is configured for transforming one or more of the at least first and second images to thereby render the at least the first and second images into a common space. In addition, the method includes aligning the at least the first and second images using results of the transforming. The method may also include generating an alignment metric using a classifier.

Abstract: Disclosed is a method, and associated apparatuses, for measuring a parameter of interest relating to a structure having at least two layers. The method comprises illuminating the structure with measurement radiation and detecting scattered radiation having been scattered by said structure. The scattered radiation comprises normal and complementary higher diffraction orders. A scatterometry model which relates a scattered radiation parameter to at least a parameter of interest and an asymmetry model which relates the scattered radiation parameter to at least one asymmetry parameter are defined, the asymmetry parameter relating to one or more measurement system errors and/or an asymmetry in the target other than a misalignment between the two layers. A combination of the scatterometry model and asymmetry model is used to determine a system of equations, and the system of equations is then solved for the parameter of interest.

Abstract: Methods and systems for charged particle microscope confocal imaging are disclosed herein. An example method includes obtaining a plurality of probe images of a portion of a sample, each probe image of the plurality of probe images obtained at a different focal depth within the sample, applying a virtual aperture to each probe image of the plurality of probe images to form a respective plurality of confocal images, and forming a three-dimensional reconstruction of the sample based on the plurality of confocal images.

Abstract: Alignment can be monitored by positioning at least one alignment verification location per alignment frame. The alignment verification location is a coordinate within the alignment frame. A distance between each of the alignment verification locations and a closest instance of an alignment target is determined. An alignment score can be determined based on the distance. The alignment score can include a number of the alignment frames between the alignment verification location and the alignment target. If the alignment score is below a threshold, then alignment setup can be performed.

Abstract: The present disclosure discloses a laser cutting base and a laser cutting device. The laser cutting base includes a base body, a recess and a filling structure. The base body includes a first surface configured to fixedly mount an element to be cut. The recess is formed by recessed inwardly from the first surface and corresponds to a position of a cutting line. The filling structure is filled in the recess and is able to prevent debris in the recess during cutting process from rebounding to the element to be cut.

Abstract: There is provided a substrate processing apparatus, including: a mounting table configured to mount a substrate with a pattern mask formed on the substrate inside a process container; a depressurization mechanism configured to perform a pressure-decreasing process of depressurizing an interior of the process container to have a pressure of 1 Pa or lower; a light irradiation mechanism configured to irradiate the substrate with a vacuum ultraviolet light after the interior of the process container is depressurized so that an internal pressure of the process container reaches a pressure of 1 Pa or lower; and a controller configured to output a control signal such that an average depressurization rate inside the process container performed by the depressurization mechanism becomes 250 Pa/sec or lower while the interior of the process container is depressurized from 10,000 Pa to 1 Pa.

Abstract: According to an embodiment, focus sensitivity information in which focus sensitivity expressing a relation between an aberration correction value set in an exposure device and a best focus when a pattern is formed on a first substrate by exposure of the exposure device using the aberration correction value, and the pattern are correlated is input. Moreover, on the basis of the focus sensitivity information and a surface height difference of a second substrate, the aberration correction value in which best focuses for a pattern group to be formed on the second substrate by exposure satisfy a first condition is calculated. In addition, the second substrate is exposed by the exposure device using the aberration correction value satisfying the first condition.

Abstract: A synthetic quartz glass substrate is prepared by furnishing a synthetic quartz glass block, coating two opposite surfaces of the block with a liquid having a transmittance of at least 99.0%/mm at the wavelength of birefringence measurement, measuring a birefringence distribution on the block by letting light enter one coated surface and exit the other coated surface, and sorting the block to an acceptable group or unacceptable group, based on the measured birefringence distribution.

Abstract: A method for qualitatively detecting aberration and determine aberration types in a photolithography system is disclosed. The method includes using a digital micromirror device (DMD) pattern to project an optical signal on a reflective substrate, acquiring a return optical signal reflected from the substrate at different focus heights (ranging from above to below best focus), forming a through focus curve based off of the return optical signal at various focus heights, comparing the through focus curve to a predetermined curve—the predetermined curve being a function of focus, and determining if a lens aberration is present. By using the existing hardware of the photolithography system to determine if a lens aberration exists, costs are maintained at a minimum and the DMD pattern creates a through focus curve (TFC) image in less than five minutes allowing for quick correction.

Abstract: A method to improve a lithographic process of imaging a portion of a design layout onto a substrate using a lithographic projection apparatus, the method including: computing a multi-variable cost function, the multi-variable cost function being a function of a stochastic variation of a characteristic of an aerial image or a resist image, or a function of a variable that is a function of the stochastic variation or that affects the stochastic variation, the stochastic variation being a function of a plurality of design variables that represent characteristics of the lithographic process; and reconfiguring one or more of the characteristics of the lithographic process by adjusting one or more of the design variables until a certain termination condition is satisfied.

Abstract: An exposure apparatus exposes a substrate with illumination light via a projection optical system, and includes a frame member, a mark detection system that detects a mark of the substrate, a mask stage system having a first movable body to hold a mask, a first encoder system having first heads that each irradiate a first measurement beam to a first grating section, a substrate stage system having a second movable body to hold the substrate, a second encoder system having second heads that each irradiate a second measurement beam to a second grating section, and a controller that controls driving of the first movable body and of the second movable body, based on measurement information of the first and second encoder systems. In each of an exposure operation and a detection operation, the positional information of the second movable body is measured by the second encoder system.

Abstract: A controller includes a memory that stores a first model corresponding to a first critical dimension of a substrate processed by a substrate processing system and a second model corresponding to a second critical dimension of the substrate. The second model includes a predicted relationship between the first critical dimension and the second critical dimension. A critical dimension prediction module calculates a first prediction of the first critical dimension of the substrate using the first model, provides the first prediction of the first critical dimension as an input to the second model, and calculates and outputs a second prediction of the second critical dimension of the substrate using the second model.

Abstract: An EUV mask according to an embodiment includes a substrate, a first line-shaped portion provided on the substrate, a second line-shaped portion provided on the substrate, a first sidewall disposed on a side surface of the first line-shaped portion, and a second sidewall disposed on a side surface of the second line-shaped portion. A first layer and a second layer are stacked in the first and second line-shaped portions. The first layer includes a first material. The second layer includes a second material. The first and second sidewalls include an oxide of the first material and cover a side surface of the first layer and a side surface of the second layer.

Abstract: A model-based tuning method for tuning a first lithography system utilizing a reference lithography system, each of which has tunable parameters for controlling imaging performance. The method includes the steps of defining a test pattern and an imaging model; imaging the test pattern utilizing the reference lithography system and measuring the imaging results; imaging the test pattern utilizing the first lithography system and measuring the imaging results; calibrating the imaging model utilizing the imaging results corresponding to the reference lithography system, where the calibrated imaging model has a first set of parameter values; tuning the calibrated imaging model utilizing the imaging results corresponding to the first lithography system, where the tuned calibrated model has a second set of parameter values; and adjusting the parameters of the first lithography system based on a difference between the first set of parameter values and the second set of parameter values.

Abstract: A maskless exposure device includes a stage on which a substrate is disposed, an optical head, and an optical source part. The optical head irradiates light to the substrate. The light source part provides the optical head with a light. The optical head irradiates the light, according to an average-focus distance, to the substrate. The average-focus distance is determined by averaging best-focus distances for a plurality of regions of the substrate, respectively.

Abstract: The present invention provides an imprint method comprising a deformation step of deforming a pattern surface of a mold so that the mold is gradually brought into contact with the imprint material outward from a central portion of the pattern surface, an obtaining step of obtaining a shift amount indicating how much a mark on the mold shifts in a direction parallel to a substrate surface due to deformation of the pattern surface, a detection step of detecting the mark on the mold and a mark on the substrate while the pattern surface is deformed, and obtaining relative positions of the mold and the substrate from a detection result, and an alignment step of aligning the mold and the substrate using the shift amount and the relative positions while the pattern surface is deformed.

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 lithographic apparatus is disclosed that has a first substrate table arranged to hold a substrate and a second substrate table arranged to hold a substrate, an imprint template holder arranged to hold an imprint template, and an imprintable medium dispenser, wherein the first substrate table is moveable between a first position located at or adjacent to the imprintable medium dispenser, and a second position located at or adjacent to the imprint template holder, and the second substrate table is moveable between the first and second positions, such that the first and second substrate tables swap positions.

Abstract: Several embodiments of photolithography systems and associated methods of overlay error correction are disclosed herein. In one embodiment, a method for correcting overlay errors in a photolithography system includes measuring a plurality of first overlay errors that individually correspond to a microelectronic substrate in a first batch of microelectronic substrates. The method also includes determining a relationship between the first overlay errors and a first sequence of the microelectronic substrates in the first batch. The method further includes correcting a second overlay error of individual microelectronic substrates in a second batch based on a second sequence of the microelectronic substrates in the second batch and the determined relationship.

Abstract: A metrology target formed by a lithographic process on a substrate includes a plurality of component gratings. Images of the target are formed using +1 and ?1 orders of radiation diffracted by the component gratings. Regions of interest (ROIs) in the detected image are identified corresponding the component gratings. Intensity values within each ROI are processed and compared between images, to obtain a measurement of asymmetry and hence overlay error. Separation zones are formed between the component gratings and design so as to provide dark regions in the image. In an embodiment, the ROIs are selected with their boundaries falling within the image regions corresponding to the separation zones. By this measure, the asymmetry measurement is made more tolerant of variations in the position of the ROI. The dark regions also assist in recognition of the target in the images.

Abstract: A method of lithography in a lithographic apparatus configured to transfer a pattern from a patterning device onto a substrate, the method including: determining a dose sensitivity of at least part of the pattern at a plurality of values of a dose, wherein the dose sensitivity is not a monotonically increasing or monotonically decreasing function of the dose. A computer product including a processor, a memory and a storage device, wherein the storage device at least stores values of, or a function describing, a dose sensitivity of at least part of a lithographic pattern at a plurality of values of dose, wherein the dose sensitivity is not a monotonically increasing or monotonically decreasing function of the dose.

Abstract: An image forming apparatus includes an image formation unit, a detection unit, a storage unit, and a control unit. When the detection unit outputs a second output value when a second recording material, which is different from a first recording material is detected, in a state where the storage unit stores a first output value output by the detection unit upon detection of the first recording material, the control unit controls an image forming condition based on at least the first output value if a differential value between the first output value and the second output value is smaller than a predetermined threshold value and controls the image forming condition based on the second output value without using the first output value if the differential value is greater than the predetermined threshold value.