Abstract: A document reading apparatus, including: a conveyance portion which conveys a document; an illuminator which illuminates the conveying document; a reading portion which reads the conveying document at a read position; a reference member arranged opposite to the read position; a correction condition calculating portion which calculates a correction condition corresponding to each of a plurality of pixel positions based on image data obtained by the reading portion reading the reference member; and a correction portion which corrects image data of the document using the correction condition, wherein the correction condition calculating portion obtains a plurality of image data of the reference member corresponding to a first pixel position and its peripheral pixel position, and calculates a correction condition at the first pixel position based on remaining image data after excluding high brightness image data and low brightness image data.

Abstract: An image reading apparatus includes an ADF driven by a motor; an image reading unit transmitting charges accumulated in a photoelectric conversion element as a shift pulse to a shift register; and a shift pulse control unit controlling an output timing of the shift pulse based on rotation of the motor. When the rotation of the motor stops, the shift pulse control unit outputs the shift pulse to transmit the charges accumulated in lighting of a light source immediately before the stoppage of the motor.

Abstract: A color measuring device includes: an image capturing unit; a reference chart; a light quantity control unit; a generating unit; a correction unit; and a calculating unit. The image capturing unit outputs image data of an image-capturing range. The reference chart has multiple patches of different densities. The light quantity control unit controls the illumination unit. The generating unit generates first correction data based on image data of the multiple patches illuminated by a first light quantity and generates second correction data based on image data of the multiple patches illuminated by a second light quantity. The correction unit corrects image data of the reference chart and a color measurement target, using the first correction data or the second correction data. The calculating unit calculates color measurement value of the color measurement target based on the corrected image data of the reference chart and the color measurement target.

Abstract: An optical scanning unit includes a light source including a plurality of light-emitting elements; a light detector to detect a light beam emitted from the light source; a light-flux splitter, angled to the optical axis of the light beam emitted from the light source, having an aperture, a portion of reduced thickness susceptible to warping, a concave face of the warped light-flux splitter as a reflecting face, and a convex face of the warped light-flux splitter opposite the concave face as a non-reflecting face; and a light-flux splitter pressing unit to press the light-flux splitter onto a light-flux splitter holding member without blocking the aperture. Light beam passed the aperture is used as a write-use light flux. The reflecting face reflects a light flux other than the write-use light flux as a monitor-use light flux. The light-flux splitter pressing unit presses a portion of maximum convexity of the non-reflecting face.

Abstract: An electrophotographic image forming apparatus including a light scanning device to scan first and second light beams, a synchronization signal detector to receive a portion of the first light beam scanned by the light scanning device and to generate a first horizontal synchronization signal, and a video signal processor including a second horizontal synchronization signal generating unit to count a synchronization signal offset and generate a second horizontal synchronization signal regarding the second light beam when the first horizontal synchronization signal is transmitted from the synchronization signal detector, and a video controller to transfer video data to the light scanning device based on the first and second horizontal synchronization signals.

Abstract: An image reading apparatus includes a reading unit, a controlling unit and a changing unit. The reading unit receives a reflected light from a sheet onto which a light is irradiated from a light source, converts the received light into an image signal, and accumulates a charge corresponding to the image signal in accordance with a reading time of the sheet. The controlling unit controls the light source to be turned off in accordance with a reading mode of the sheet so that an amount of the accumulated charge does not reach a saturated amount. The changing unit changes an amplification factor of an amplifying unit in accordance with a turn-off time of the light source to amplify the image signal to a predetermined level when the controlling unit controls the light source to be turned off. The amplifying unit amplifies the image signal at a predetermined amplification factor.

Abstract: In a collimator lens, in a case where divergent light emitted from a position P1 at a distance S1 from a second face enters the second face and imaging is performed at a position P2 at a distance S2 from a first face, in a temperature range of 0° C. to 60° C. and in a range of the emission wavelength of the light source which changes within the temperature range, and when a minimum value of a wavefront aberration of an image, which is generated at the position P2 by the divergent light emitted from the position P1 in a range of 0<S1/S2?50, is WF1, and when a minimum value of a wavefront aberration of an image, which is generated at the position P2 when parallel light satisfying S1=? enters the second face, is WF2, a relationship of WF1<WF2 is satisfied.

Abstract: An optical scanning apparatus includes a light source, rotational polygonal mirror, correction data calculating unit, modification computing unit, and adjustment unit. The adjustment unit adjusts drive current supplied to the light source using the correction data calculated by the correction data calculating unit when a first of a plurality of modes is selected or using the correction data calculated by the modification computing unit when a second of the plurality of modes is selected.

Abstract: An image reading apparatus, an image reading method and a program are provided for favorably correcting color misalignment in a sub-scanning direction of a read signal read by a plurality of line sensors without increasing a circuit scale or processing time. To accomplish this, the image reading apparatus sets, as a reference signal, the read signal that is output from one of the plurality of line sensors, and detects a correlation between the reference signal and each of a plurality of read signals output from line sensors other than the one of the plurality of line sensors of a plurality of lines that are displaced in predetermined line units from a line from which the reference signal is read, and selects a read signal having a high correlation with the reference signal as a read signal from the line of the reference signal.

Abstract: An image scanner includes: a light source that irradiates, with light, a recording medium on which an image is formed; a light receiving portion that receives light reflected by the recording medium; and a reflecting portion that has a reflecting surface for measuring the amount of specular reflection light coming from the light source, the specular reflection light being included in the light received by the light receiving portion.

Abstract: An image correction method is applied to a scanner device. The scanner device includes a main case, a drive module, an optical module, an analog-to-digital converter, a first-in and first-out data buffer, a data flow control unit, a set unit, a data classification unit and a memory storage unit which are electrically connected and assembled in the main case. The scanner device executes a program statement set by the set unit in the memory storage unit to get values for building an update shading table. The scanner device utilizes the update shading table to compensate pixel values corresponding to red, green and blue light of each scanned line of an image for doing a luminance compensation of image pixels corresponding to the red, green and blue light of each scanned line of the image so as to complete an image correction of each scanned line of the image.

Abstract: A light-source control device includes a light source including a first light emitter for emitting light and a second light emitter for emitting light due to the light emitted by the first light emitter; a constant current unit configured to maintain a current constant that is input via the light source from a power supply; a switching unit configured to switch the current to be input to the constant current unit at a designated duty ratio and cycle; and a control unit configured to control the current applied to the light source so that a rise transition time and a fall transition time of the current applied to the light source are nearly equal to each other.

Abstract: An imaging device including a base and an enclosed chamber positioned on the base. The enclosed chamber has a scanning surface inclined with respect to the base, a reflecting member positioned opposite to the scanning surface and an imaging member adjacent the scanning surface and oriented towards the reflecting member. The imaging member is illuminated with a red, a green, a blue, and an additional color LED. In one embodiment the additional color is a color other than red, green, and blue. In an alternate embodiment the additional color is Ultraviolet (UV) or Infra-Red (IR).

Abstract: A spectral colorimetric apparatus for detecting a color of an image of a subject, including: an illumination optical system illuminating the subject on a detection surface; a spectral optical system including a spectral element spectrally separating the beam diffused by the subject and a light receiving element array detecting a spectral intensity distribution; and a guiding optical system for guiding a beam diffused by the subject, wherein: the detection surface is parallel to a spectral plane including a principal ray of a beam entering the spectral optical system and a principal ray of a beam spectrally separated; the principal ray of the beam enters the spectral optical system within the spectral plane obliquely to a line joining a center of the light receiving element array with a surface vertex of the spectral element; and a light receiving surface of the light receiving element array is orthogonal to the spectral plane.

Abstract: A plurality of line sensors corresponding to a plualrity of color components receive reflected light passed through an imaging unit and convert the light into a plurality of color component data. A correcting unit performs color misalignment correction based on a reference color component for which resolution performance is lowest among the plurality of color component, on the color component data corresponding to other color components.

Abstract: In a method for document digitization, an apparatus generates a first image of a document sheet by irradiating the document sheet using a first light source and detecting the document sheet irradiated with light from the first light source, which enables detection of ink on the document sheet that defines a marked portion. The apparatus further generates a second image of the document sheet by irradiating the document sheet using a second light source and detecting the document sheet irradiated with light from the second light source, which enables detection of content on the document sheet. The apparatus further obtains a region of the second image that corresponds to the marked portion of the document sheet based on the first image.

Abstract: An image reading apparatus includes a body; a circuit board fixed to the body; a light emitter disposed on a first surface of the circuit board, the light emitter emitting light with which a document is irradiated; a light guide disposed opposite the circuit board with the light emitter therebetween, the light emitted from the light emitter passing through the light guide; an urging unit; a supporting unit fixed to the body; and a pressing unit. The pressing unit includes a first portion and a second portion. The first portion is pressed in a direction from the light emitter toward the light guide as a result of receiving a force from the urging unit. The second portion presses the light guide against the light emitter as a result of receiving a reaction force from the supporting unit when the first portion is pressed.

Abstract: An illuminator, a scanner module and an image scanning apparatus are provided. The scanner module includes an illuminator that includes a light source, a light guide extending in a main scanning direction to change a direction of the light from the light source, a guide holder recessed with a light guide mounting portion in which the light guide is mounted, and at least one supporting protrusion protruding from an entrance of the light guide mounting portion into the light guide mounting portion to support the light guide received in the light guide mounting portion. As the light guide is supported by the supporting protrusion formed at the entrance of the light guide mounting portion, it is possible to reduce deformation of the light guide and/or to prevent the light guide from being falling out of the light guide mounting portion when subjected to, e.g., a shock.

Abstract: An image reading apparatus includes a first reading unit, a second reading unit, and a determination unit. The first reading unit reads an image on a first side of a document conveyed through a document conveyance path. The second reading unit is disposed in the document conveyance path at a reading position that is different from a reading position of the first reading unit and reads an image on a second side that is different from the first side on the document. The determination unit determines whether the document is a color document, according to whether a color image is included in an image in a predetermined region of the first side read by the first reading unit, and in an image in a region that is different from the predetermined region in the first side and read by the second reading unit.

Abstract: An erecting equal-magnification lens array plate includes: first and second lens array plates; first, second and intermediate light shielding member. The first, second and intermediate light shielding member are halved by a splitting plane parallel with the main scanning direction. One of the first light shielding member pieces, one of the second light shielding member pieces, and one of the intermediate light shielding member pieces produced by halving the members are integrated to form a first holder piece. The other of the first light shielding member pieces, the other of the second light shielding member pieces, and the other of the intermediate light shielding member pieces produced by halving the members are integrated to form a second holder piece. The erecting equal-magnification lens array plate is assembled by sandwiching the first lens array plate and the second lens array plate by the first holder piece and the second holder piece.

Abstract: An image sensor unit includes a reflection reading light source that illuminates a bill, a substrate on which the reflection reading light source is mounted, a reflection reading light guide that guides the light emitted by the reflection reading light source to the bill, a rod-lens array that focuses the light from the bill, a light receiving element that receives the light from the rod-lens array, a sensor substrate on which the light receiving element is mounted, and a frame that houses the substrate, the reflection reading light guide, the rod-lens array and the sensor substrate. The sensor substrate has a passage hole and is disposed closer to the bill than the substrate. The frame is disposed with the reflection reading light guide inserted into the passage hole, so that the light from the reflection reading light source reaches the bill through the passage hole.

Abstract: A method for compensating for effects of illumination when comparing soft proofs to hard copy proofs viewed under non-standard illumination comprises adjusting a standard illumination display profile until estimates of device independent colors produced by the display based on the adjusted profile match the colors corresponding to the non-standard illumination within a predefined tolerance.

Abstract: A protruding locking pawl is provided at an end of a light guide which corresponds to a first light input surface. A recessed locking portion is formed in a frame so that the locking pawl can be locked in the locking portion. A light blocking member is slidably loosely inserted into a position where the light blocking member covers a longitudinal end of the light guide which corresponds to a second light input surface. Even if expansion and contraction occurs in the longitudinal direction of the light guide, the design dimensions of a first gap A and a second gap B can be maintained; the first gap A is formed between the first light input surface and a first light source, and the second gap B formed between the second light input surface and a second light source. Therefore, possible leakage current can be prevented.

Abstract: An image processing apparatus includes a calculation to calculate a compression gain that is applied to a low-frequency component of an input image and an amplification gain that is applied to a high-frequency component of the input image, a generation to generate a display image in which a pixel value of a pixel of the input image is corrected based on the compression gain and the amplification gain calculated by the calculation unit, and a display to display the display image.

Abstract: A display apparatus according to this invention performs control so as to reduce the difference between image data input to a display unit and an image which is displayed on a display surface and acquired by an acquisition unit, based on the image data and the image.

Abstract: A projector apparatus includes: a projection unit that projects an image onto a projection surface; a reflectance distribution detection unit that detects a reflectance distribution at the projection surface; a density distribution detection unit that detects a density distribution of a base pattern at the projection surface; a smoothing unit that smooths the reflectance distribution and the density distribution; an input unit that inputs image data; a correction unit that corrects the input image data based upon the smoothed reflectance distribution, the smoothed density distribution and input/output characteristics of the projection unit; and a control unit that controls the projection unit so as to project the image based upon the image data having been corrected.

Abstract: A component imaging method includes: an imaging preparation step of obtaining, for each of the plurality of components, an optimum lighting intensity; a component imaging step of using a line sensor and a lighting device, to integrally move the components relative to this line sensor, with the components being aligned in a main scanning direction of the line sensor, and to acquire images of the components while switching a lighting intensity of the lighting device sequentially to the optimum lighting intensity of each of the components for each imaging line; and an image processing step of compensating a line image, which is imaged at a lighting intensity other than the optimum lighting intensities, on the basis of a ratio of the lighting intensity at which the line image is obtained and the optimum lighting intensity of each of the components of the obtained component images, for the component image.

Abstract: An illumination system for a scanner according to one example embodiment includes an array of visible light emitting diodes including a red, a blue and a green light emitting diode and an ultraviolet light emitting device configured to emit light predominantly in the ultraviolet region of the electromagnetic spectrum. During a scan sequence of the red, blue and green light emitting diodes, at least one of the visible light emitting diodes and the ultraviolet light emitting device are positioned to simultaneously illuminate an object being scanned. In one form, during the sequence, the blue light emitting diode and the ultraviolet light emitting device are simultaneously illuminated while in another the red light emitting diode and the ultraviolet light emitting device are simultaneously illuminated.

Abstract: Systems and methods systems and methods for calibrating field uniformity are disclosed. An exemplary method includes scanning the imaging area including a first media to obtain optical data for a specular reflectance map. The method also includes scanning the imaging area including a second media to obtain optical data for a diffuse reflective map. The method also includes storing the specular reflectance map and the diffuse reflective map for adjusting actual pixel values during an imaging operation.

Abstract: The image reading apparatus includes an LED, a light guiding body, and a photoelectric conversion element. The light guiding body has a plurality of prisms for diffusing light. The plurality of prisms includes: at least one first prism that is disposed on an incident surface side in the main scanning direction; and at least one second prism that is disposed on an opposite end side to the incident surface side in the main scanning direction. In the first prism, an angle of a prism incident plane with respect to the main scanning direction is greater than an angle of a prism anti-incident plane with respect to the main scanning direction. In the second prism, an angle of a prism incident plane with respect to the main scanning direction is smaller than an angle of a prism anti-incident plane with respect to the main scanning direction.

Abstract: An image reader is provided, which includes a light-emitting-timing setting unit configured to divide a non-light-emitting time during which none of light sources emits light in a predetermined reading period into a plurality of segmental non-light-emitting times and set a light-emitting moment separately for each light source as a moment to emit the light in the predetermined reading period, such that the segmental non-light-emitting times are arranged in a dispersed manner in the predetermined reading period, and a controller configured to control each light source to emit the light during a light-emitting time determined separately for each light source at the light-emitting moment set by the light-emitting-timing setting unit.

Abstract: A light projection unit includes a substrate, a plurality of light emitting elements arrayed on the substrate in a main scanning direction and including light emitting surfaces, a light guide facing the light emitting surfaces to direct light projected from the light emitting elements onto an illumination target and including a first positioning portion, and a holder including a second positioning portion that engages the first positioning portion of the light guide to position the light guide on the holder. The first positioning portion of the light guide is positioned between centers of light emission of adjacent light emitting elements in the main scanning direction of the substrate when the first positioning portion engages the second positioning portion of the holder.

Abstract: An image sensor unit includes: a light guide reflecting light rays entering through a first light entering surface and a second light entering surface provided at both ends thereof, by a reflection surface to make the light rays exit through a light exiting surface and illuminates an original; a first light source provided near the first light entering surface; a second light source provided near the second light entering surface and different in wavelength from the first light source; and a first reflection part and a second reflection part provided on the reflection surface and composed of dot patterns constituted of two kinds of dots different in spectral reflectance.

Abstract: A reading device includes a first illuminating section that illuminates a reading area with first illumination light of a first direction; a second illuminating section that illuminates the reading area with second illumination light of a second direction; a light-receiving section that receives reflection light of the first illumination light and reflection light of the second illumination light reflected from the reading area, the first illumination light being applied from the first illuminating section and the second illumination light being applied from the second illuminating section; and reflecting members that are disposed side by side in the reading area in a widthwise direction thereof, and that have first and second reflecting surfaces.

Abstract: An image reading apparatus irradiates a document with light, and reads the document image based on the reflected light and includes a light source which includes a plurality of LEDs, and irradiates the document with light. The apparatus also includes an LED current adjusting unit which sets the amount of current to be supplied to each LED by changing the current amounts from the end portion to the central portion in the main scanning direction of document reading, and a driving circuit which drives the LEDs by the current amounts set by the LED current adjusting unit in correspondence with the LEDs.

Abstract: In an image reading apparatus, an image reading unit performs a reading operation to generate image data defined by the reading region. The reading region includes a first region and a second region. The image data includes first data and second data. The first data corresponds to the first region. The second data corresponds to by the second region. The original document passes through the first region and not passes through the second region. A displacing unit displaces the opposing member farther away from the image reading unit when the original document is present in the reading region than a position of the opposing member when the original document is not present in the reading region. A controller determines that an edge reaches the reading position when the second data satisfies a prescribed condition.

Abstract: The image reading device includes a light emitting portion, stick-like light guiding member, holding member and case member. An end portion the light guiding member is disposed to face the light emitting portion. The holding member holds the light emitting portion and the light guiding member. The holding member has first and second positioned portions. The first and second positioned portions are formed at one end part and another end part of the holding member in a main scanning direction, respectively. The holding member is attached to the case member. The case member has first and second positioning portions. The first and second positioning portions are formed integrally with the case member. The first and second positioning portions are configured to restrict the inserted first and second positioned portions from moving in a direction transverse to the main scanning direction, respectively.

Abstract: An image reading device has a light emitting unit. The light emitting unit has a light emitting portion, a light guiding member, a holding member and a case member. The light guiding member is disposed along a main scanning direction, and an end portion of the light guiding member faces the light emitting portion. The light guiding member has a light irradiating portion which emits light to an outside. The holding member holds the light emitting portion and the light guiding member. In addition, the holding member has a first holding portion that directly or indirectly positions and holds the light emitting portion, and a second holding portion that positions and holds one end or both ends of the light guiding member. The case member houses the holding member that is in a state of being positioned.

Abstract: An image reading apparatus includes a light guide arranged between a light source and a document. The light guide has a light incident surface at a side of the light source, light from the light source, is incident, a first light emitting surface at a side of the document, a second light emitting surface different from the first light emitting surface, a first reflecting surface between the first and second light emitting surfaces, a second reflecting surface between the light incident surface and the second light emitting surface, and a third reflecting surface facing the second reflecting surface. The first reflecting surface reflects light toward the first light emitting surface. The second reflecting surface reflects light toward one of the second light emitting surface and the first and third reflecting surfaces. The third reflecting surface reflects light toward the second light emitting surface or the first reflecting surface.

Abstract: Disclosed are an illuminator and an image forming apparatus employing an illuminator. The illuminator includes a light guide to guide light generated from a light source to an object to be illuminated. The light guide includes at least one incidence face facing the light source and an emission face configured to emit the light to the target object. A diffusion pattern may be formed on the emission face to extend from one longitudinal end to the other longitudinal end of the emission face. The emission face may have a constant cross section or a varying cross section along a longitudinal direction thereof. The illuminator may be part of an image reading device to uniformly or near uniformly irradiate light to a document. The illuminator may also be incorporated in an image forming apparatus to irradiate light to a photosensitive body for elimination or reduction of electric potential from the photosensitive body.

Abstract: In an image-reader, the first counter is configured to count a first count value based on a first clock. The second counter is configured to count a second count value based on a second clock. The first reading unit is configured to read a first surface of a document sheet based on the first count value. The second reading unit is configured to read a second surface of the document sheet based on the second count value. The second surface is opposite surface of the first surface. When the first count value reaches a prescribed first value, both the first counter value and the second count value are reset.

Abstract: A document reading apparatus includes a white LED including an LED and a fluorescent material and configured to illuminate a document reading position with light, a reading unit having a color line sensor and a monochrome line sensor and configured to read an image of a document illuminated with the light emitted from the white LED, and a filter arranged on an optical path between the monochrome line sensor and the document, and wherein the filter is configured to suppress transmission of light at a peak wavelength of the LED so that, regarding an intensity of light to be received on the monochrome line sensor, the intensity of the light at the peak wavelength of the LED is smaller than the intensity of the light at the peak wavelength of the fluorescent material when the light emitted from the LED is received.

Abstract: An image forming apparatus that forms an image includes: a photosensitive element; an optical scanning device that includes a light source, and scans a surface of the photosensitive element in a main scanning direction with light emitted from the light source to form a latent image; a developing unit that develops the latent image; a photosensitive element period detecting sensor that detects a rotation period of the photosensitive element; a density sensor that detects a density variation of an image developed by the developing unit, in a sub scanning direction; and a processing device that corrects a driving signal of the light source according to the image information, based on an output signal of the density sensor and an output signal of the photosensitive element period detecting sensor.

Abstract: Color management in which a spectral gamut is determined for spectral gamut mapping by constructing subdivisions of a set of samples spanning the spectral gamut. The samples are designated by specifying device values and are subdivided based on their lightness, chroma and hue under a reference illuminant such that the number of samples in each subdivision is limited by a predetermined number. A color value to be spectrally gamut mapped is accepted, and converted into a colorimetric value under the reference illuminant. The converted colorimetric value includes a lightness, a chroma and a hue. Subdivisions within a tolerance of the converted colorimetric value are identified using its lightness, chroma and hue. Samples within the identified subdivisions are searched to find a sample that matches acceptably to the color value relative to an objective function.

Abstract: Methods of image enhancement are disclosed. In one aspect, the method of image enhancement is for use with an image capture device, such as a security document reader, for the attenuation, separation or reduction of reflections from objects, such as security documents.

Abstract: The present invention discloses an image sensor, specifically a full spectrum recognition image sensor capable of reading and recognition image information for all of ultraviolet light, visible light and infrared light, which comprises a sensor substrate, photosensitive parts set on the sensor substrate and arranged in a straight line, a lens set on an upper portion of the sensor substrate, a light source set beside the lens, and a framework capable of accommodating said sensor substrate, said lens and said light source.

Abstract: An erecting equal-magnification lens array plate comprises first and second lens array plates stacked on one another, a fourth surface light-shielding wall, and an intermediate light-shielding wall. An intermediate through hole formed in the intermediate light-shielding wall is formed such that the hole diameter is progressively smaller in a tapered fashion away from the first lens array plate toward the second lens array plate. An angle of inclination ? of an interior wall surface of the intermediate through hole with respect to a optical axis is given by ??tan?1(D4/(Gap+L2+H4))/2 where Gap denotes a gap between the lens array plates, L2 denotes a thickness of the second lens array plate, H4 denotes a height of the fourth surface light-shielding wall, and D4 denotes a diameter of the opening of the fourth surface through hole formed in the fourth surface light-shielding wall facing the image plane.

Abstract: An apparatus and a method for controlling a light source used for image reading according to a user activity are provided. The light source controller being coupled to a light source and configured to change the power of the light source from an OFF state to an ON state when a user activity signal having a first state is output, the user activity signal having the first state being assumed to be output when a user activity, other than an instruction to begin scanning, that is assumed to ultimately cause output of the image reading start signal has been performed on the image reading apparatus.

Abstract: This disclosure describes techniques and apparatuses for reducing color fringes. In some embodiments, inaccuracies from color-insensitive sensors are corrected. Inaccuracies can be corrected in part by shortening a first illumination made temporally proximate a second illumination. By so doing, a center of the image captured for a first illumination is moved toward the image captured for a second illumination, which reduces a color fringe.

Abstract: An image display device includes: an external light measurement unit measuring the illuminance of an external light a plurality of times, and generating a measurement value indicating the illuminance; a storage unit storing history data which shows the measurement values, and color mode data which shows a correspondence between the illuminance and a color mode; a determination unit, based on the history data, determining whether or not it is a changed condition wherein the illuminance changes upward or downward, or the illuminance fluctuates; and an adjustment unit, in the event that it is not the changed condition, determining the color mode to be applied based on the measurement values and the color mode data, and adjusting the color or brightness of an image in accordance with the color mode, and in the event that it is the changed condition, continuing the adjustment currently being applied as the image adjustment.