Abstract: An optical member includes a polarization film configured to polarize light. The optical member may further include a sealing member that overlaps the polarization film. The optical member may further include a retardation film disposed between the polarization film and the sealing member and configured to cause phase retardation. The optical member may further include a lens film disposed between the retardation film and the sealing member and includes a plurality of concave lens units that defines a plurality of air units, which may be sealed by the sealing member.

Abstract: A zoom lens barrel assembly includes a first barrel, a second barrel, a lens barrier, and a transparent member. The first barrel supports at least one lens. The second barrel surrounds at least a portion of an outer surface of the first barrel, and supports the first barrel to protrude along an optical axis direction. The lens barrier is disposed on a front side of the first barrel, and is moved in a direction that intersects an optical axis to expose the at least one lens when the first barrel is protruded. The transparent member is disposed on a front side of the lens barrier, and prevents impurities from entering the first barrel.

Abstract: This invention provides a unit for an image display device in which an optical film laminate and a panel for an image display device are laminated with an adhesive layer therebetween. The optical film laminate contains a polarizer and a polarizer protection functional layer laminated to only one surface of the polarizer. The adhesive layer is laminated to the surface of the polarizer that is opposite to the surface that contacts the polarizer protection functional layer. The panel for an image display device is laminated to the surface of the adhesive layer that is opposite to the surface that contacts the polarizer. A glass transition temperature of the adhesive layer is in a range of from 50° C. to 90° C.

Abstract: An apparatus for inhibiting heating of an enclosure is disclosed. The apparatus comprises a covering configured to shade at least a portion of a surface of the enclosure and includes a plurality of retroreflective elements. The plurality of retroreflective elements are configured to retroreflect electromagnetic beams primarily at wavelength in a range between about 380 nm and about 780 nm or sub-range thereof. The plurality of retroreflective elements receive the electromagnetic beams along beam entry paths and reflect the electromagnetic beams along beam exit paths. The beam entry paths and the beam exit paths have substantially the same elevation angle and may also have substantially the same azimuthal angle. Further, the plurality of retroreflective elements may include retroreflective elements configured to diffusively and/or specularly scatter audible sound wavelengths, RF wavelengths, and/or thermal infrared energy.

Abstract: A diffractive optics element includes a substrate configured of a sapphire substrate and a diffractive optics structure, provided on the substrate, that forms an image when a laser beam is incident thereon. The diffractive optics structure has a diffractive optics portion, and the diffractive optics portion has a base material and a diffractive optics layer disposed on the base material. The thickness of the base material is no greater than 20 ?m.

Abstract: Described herein is a diffraction grating (1) for use in an optical system. The diffraction grating includes a substrate (2) and an array of elongate diffracting elements (3) arranged in a grating profile across the substrate. The grating profile imparts a predefined phase change to optical beams to at least partially correct the beams for optical aberrations present in the optical system.

Abstract: A first layer which has a surface including a diffraction grating part having a plurality of fine concavities and convexities and a second layer which is embedded in the diffraction grating part with no space therebetween are formed on a transparent substrate. A recess part having a fixed width is formed on the outer periphery of the first layer. An outer fence part having a fixed width is formed on the outer periphery of the recess part. The second layer is also embedded in the recess part.

Abstract: The etalon has a first light transmission body which causes a positive change in a light path length with respect to a temperature increase change, a second light transmission body which causes a negative change in a light path length with respect to a temperature increase change, a first reflection film which covers a first outer surface, a first anti-reflection film which covers a first inner surface, a second anti-reflection film which cover a second inner surface, and a second reflection film which covers a second outer surface. The first inner surface and the second inner surface face each other across a gap there between.

Abstract: A near-eye display system includes (a) a near-eye display device, having a display and capable of providing, to a pupil of a user, an image from the display superimposed on an ambient scene, and (b) a fixture for coupling the near-eye display device to a holder mounted to the user, wherein the fixture has a plurality of degrees of freedom for alignment of the display device with respect to the pupil.

Abstract: Method of horizontal widening of angular field of view of collimating optical system using several unified ax symmetric collimating optical systems spaced out horizontally with angular fields of view of rectangular shape with their boundaries oriented horizontally and vertically and their axes are turned horizontally relative to each other so that adjacent vertical boundaries of angular fields of view of neighboring systems coincide and full angular field of view of collimating optical system is sum of angular fields of view of unified optical systems included in it and to display total virtual information collimating optical system is conjugated with two-component combiner and primary image creators e.g. LCDs are located in focal planes of unified optical systems and wide-angle panoramic collimating optical system with horizontal field of view up to 360° can be build also.

Abstract: A plastic lens includes a first surface and a second surface. The second surface is opposite to the first surface. At least one of the first surface and the second surface includes an optically effective portion and an outer portion. The outer portion surrounds the optically effective portion. The outer portion includes a rugged region and an abutting region. The rugged region has a plurality of protrusions thereon. The abutting region is disposed farther from a center of the plastic lens than the rugged region.

Abstract: An eyepiece lens includes: a first lens having positive refractive power, the first lens having a convex surface that faces toward an eye point side; and a second lens having positive refractive power, the second lens having a convex surface that faces toward the eye point side. The first and second lenses are arranged in order from the eye point side. Following conditional expressions are satisfied, 3.0>(h×?)1/2/E>1.2??(1) 2.3>(L?E)/h>1.5??(2) where h is a height of the image at a horizontal end, ? is a half angle of view in a horizontal direction, E is a distance from an eye point to the first lens, the distance being an eye relief, and L is a distance from the eye point to the image.

Abstract: In an optical system for projection that is telecentric on a reduction side, a correction lens group substantially consisting of a part of lens groups in the optical system for projection is configured to move in the direction of an optical axis to correct a shift in a focal position caused by a change in temperature, and predetermined conditional formulas are satisfied.

Abstract: A method of fabricating a liquid lens array creates an array of through holes of axisymmetric cross-section through a central plate, forms conductive traces on the side walls of each of the through holes and on a portion of the top and bottom surfaces of the central plate contiguous with each through hole, and bonds the bottom surface of the central plate around each through hole to the top surface of a transparent base plate, forming an array of cavities. The method applies an insulating layer to the side walls of each cavity, portions of the top surface of the base plate lying within each cavity, and portions of the top surface of the transparent central plate surrounding each cavity, introduces a polar liquid and a non-polar liquid into each cavity; and bonds the top surface of the central plate to the bottom surface of a transparent top plate.

Abstract: A lens barrel includes: a lens holder which holds a lens group and includes a cam follower; a rotating cylinder including on a circumferential surface thereof a cam groove; a guide member to which the rotating cylinder is rotatably provided, which guides the lens holder to move in an optical axis direction; and a transmission member which transmits a drive force outputted from a drive source to the rotating cylinder. When the drive force is transmitted and the rotating cylinder rotates, the lens holder is guided in the optical axis direction and the cam groove has contact with the cam follower, and thereby the lens holder moves back and forth in accordance with a rotation posture of the rotating cylinder. The transmission member is provided on a more inner side than one, which is provided on an outermost side, of the lens holder, the guide member, and the rotating member.

Abstract: A photographic wide-angle lens system with internal focusing has a front array (II) of negative refractive power that is rigid within itself and fixed on the object-side, a rear array (III) of positive refractive power that is rigid within itself and fixed on the image side of an aperture diaphragm (A), and a focusing array (II) of positive refractive power having an optical single element (5) that is arranged between the front array (I) and the aperture diaphragm A and is axially movable from a maximum axial position on the object side to a maximum axial position on the image side to vary the focus distance from its maximum to its minimum value. The optical single element of the focusing array (II) has at least one aspheric surface (51, 52) and the image-side end lens (9) of the rear array (III) is configured as a positive, aspheric meniscus lens.

Abstract: A member having an arbitrary shape having a closed curve can be easily subjected to laser processing within a short time. A lens and a laser processing apparatus equipped with the lens are for cutting a material to be cut into a member having an arbitrary shape having a closed curve and include a convex cylindrical lens which is molded to have a closed path so that a line that connects vertices of a cylindrical surface of the convex cylindrical lens has the same form as the arbitrary shape having the closed curve.

Abstract: The distance along the optical axis from the surface of a first lens toward the object side to an image formation plane is 10 mm or less in an imaging lens. The imaging lens is constituted by: the first lens having a positive refractive power and a convex surface toward an object side; a second lens having a negative refractive power; a third lens having a positive refractive power; a fourth lens having a negative refractive power; a fifth lens having a positive refractive power; and a sixth lens having a surface toward an image side which is concave in the vicinity of an optical axis and convex at the peripheral portions thereof. An aperture stop is provided more toward the object side than the surface of the third lens toward the image side.

Abstract: Present embodiments provide for a mobile device and an optical imaging lens thereof. The optical imaging lens comprises five lens elements positioned in an order from an object side to an image side. Through controlling the convex or concave shape of the surfaces of the lens elements to allow the thickness of the second lens element and the sum of all air gaps between all five lens elements along the optical axis satisfying the relation: 0.20<T2<0.50 (mm) and 0.27<(T2/Gaa)<0.40, the optical imaging lens shows better optical characteristics and the total length of the optical imaging lens is shortened.

Abstract: A device comprises at least one optics member (O) comprising at least one transparent portion (t) and at least one blocking portion (b). The at least one transparent portion (t) is made of one or more materials substantially transparent for light of at least a specific spectral range, referred to as transparent materials, and the at least one blocking portion (b) is made of one or more materials substantially non-transparent for light of the specific spectral range, referred to as non-transparent materials. The transparent portion (t) comprises at least one passive optical component (L). The at least one passive optical component (L) comprises a transparent element (6) having two opposing approximately flat surfaces substantially perpendicular to a vertical direction in a distance approximately equal to a thickness of the at least one blocking portion (b) measured along the vertical direction, and, attached to the transparent element (6), at least one optical structure (5).

Abstract: A variety of optical arrangements and methods of modifying or enhancing the optical characteristics and functionality of these optical arrangements are provided. The optical arrangements being specifically designed to operate with camera arrays that incorporate an imaging device that is formed of a plurality of imagers that each include a plurality of pixels. The plurality of imagers include a first imager having a first imaging characteristics and a second imager having a second imaging characteristics. The images generated by the plurality of imagers are processed to obtain an enhanced image compared to images captured by the imagers.

Abstract: The imaging lens substantially consists of a first lens group, an aperture stop, a positive second lens group which is a focusing group, and a third lens group in this order from the object side. The first lens group substantially consists of a positive first sub lens group composed of a negative meniscus lens, a positive meniscus lens, and a positive lens; and a second sub lens group including a negative lens and a cemented lens, in this order from the object side. The second lens group substantially consists of a positive single lens or a cemented lens. The third lens group substantially consists of a cemented lens, a positive lens, and a negative lens in this order from the object side.

Abstract: A centering method for holding a lens, which has been molded using a molding die, between a pair of holders of a bell clamp system, and centering the outer circumference of the lens, this method including: a first step of using a planar part of the lens, formed using a molding surface of a molding die, to position the lens with respect to a guidance part of a positioning member configured to enable the positioning of the lens, and a second step of holding the lens between one and the other holders and another holder so that the optical axis of the lens positioned in the first step aligns with the central axis of the one holder. It is possible to prevent the optical surface of the workpiece lens and an antireflective film from being scratched when centering an aspherical lens or a spherical lens as the workpiece lens.

Abstract: A sight includes a cylinder, a first lens, a first lens seat, and at least one first elastic member. The first lens is disposed in the cylinder. The first lens seat carrying the first lens is disposed in the cylinder. The first elastic member is disposed between an outer surface of the first lens seat and an inner periphery of the cylinder, wherein the first lens seat is tightly fitted with the cylinder and light enters the cylinder through the first lens.

Abstract: In a composite molded lens, a press-formed lens body is integral with an injection-molded lens frame. The lens body has a lens portion and a flange portion surrounding the lens portion. Eight projections are radially formed on a top surface of the flange portion. The height of the projection increases toward an outer peripheral edge side of the flange portion. A recess is formed on an outer peripheral edge face of the flange portion and located at a position on a line extending from the projection. The recess increases torsional resilience of a joint surface between the lens body and the lens frame and strengthens bonding force there between.

Abstract: A lead screw device includes a lead screw including a thread portion, and a driven body which engages with the thread portion, and moves in an axis direction of the lead screw along with rotation of the lead screw about an axis, the driven body including a pair of driven members disposed to sandwich the lead screw in a radial direction, wherein the pair of driven members is biased in a direction which sandwiches the lead screw in the radial direction, and a tooth portion provided in each of the driven members engages with the thread portion of the lead screw by a biasing force.

Abstract: An adjusting assembly for a lens of a camera has a hollow housing with a mounting portion, at least one driving ring mounted around the lens, at least one turning rod mounted through the mounting portion and engaging with the at least one driving ring, and at least one limiting ring. The at least one limiting ring is embedded in the mounting portion of the housing and prevents the at least one turning rod from dropping out of the housing. The mounting portion is integrally formed on the housing and has an enlarged thickness that allows the at least one turning rod to be stably mounted on the housing. The at least one turning rod is embedded in the housing, such that appearance of the housing is smooth and pleasing.

Abstract: A base member fixed to a vehicle, a housing with a rearview mirror, a motor component to rotate the rearview housing relative to the base, two sets of ramps independent of each other, capable of sliding on corresponding fixed ramps of the base element and first and second resilient elements. The ramps of the first and second sets have different inclinations and the resilient elements have different spring rates from one another, depending on whether the drive housing is manually or motor driven.

Abstract: A method for erecting a solar field includes inserting piles into the ground in a predefined pattern covering an area of the solar field, and deploying rails between the piles. Elements of an array of solar collectors are transported along the rails to respective deployment locations in the solar field. The solar collectors are erected on the piles using the elements at the respective deployment locations.

Abstract: A protective transparent enclosure (such as a glasshouse or a greenhouse) encloses a concentrated solar power system (e.g. a thermal and/or a photovoltaic system). The concentrated solar power system includes one or more solar concentrators and one or more solar receivers. Thermal power is provided to an industrial process, electrical power is provided to an electrical distribution grid, or both. In some embodiments, the solar concentrators are dish-shaped mirrors that are mechanically coupled to a joint that enables rotation at a fixed distance about respective solar collectors that are fixed in position with respect to the protective transparent enclosure. In some embodiments, the solar collectors are suspended from structure of the protective transparent enclosure and the solar concentrators are suspended from the solar collectors. In some embodiments, the greenhouse is a Dutch Venlo style greenhouse.

Abstract: A support system for holding solar mirrors of a solar trough system includes a frame for supporting the mirrors. The system includes a rib attached to the frame. The system includes at least a first roller engaged with the rib along which the rib moves as the frame moves. A method for moving a frame supporting solar mirrors of a solar trough system includes the steps of moving the frame on a roller guided by a rib engaged with the roller and attached to the frame bottom to a first position. There is the step of moving the frame on the roller guided by the rib engaged with the roller and attached to the frame bottom to a second position. A roller for engaging with a rib attached to a frame that holds mirrors of a solar trough system. An apparatus for cleaning solar mirrors on a frame of a solar trough system. A method for cleaning mirrors on a framework of a solar trough system. A rib for a frame that holds solar mirrors of a solar trough system which engages with a roller.

Abstract: A color filter including a substrate, a plurality of single film filter units and a plurality of multi-film filter units is provided. The substrate has a first region and a second region. The single-film filter units are respectively disposed on the substrate and within the first region. The multi-film filter units are respectively disposed on the substrate and within the second region. When a white beam is projected on the color filter, the single-film filter units and the multi-film filter units reflect a plurality of color beams. The multi-film filter units include a plurality of first multi-film filter units. When the white beam is projected on the first multi-film filter units, the first multi-film filter units reflect a first color beam.

Abstract: A head transducer, configured to interact with a magnetic recording medium, includes a first sensor having a temperature coefficient of resistance (TCR) and configured to produce a first sensor signal, and a second sensor having a TCR and configured to produce a second sensor signal. One of the first and second sensors is situated at or near a close point of the head transducer in relation to the magnetic recording medium, and the other of the first and second sensors spaced away from the close point. Circuitry is configured to combine the first and second sensor signals and produce a combined sensor signal indicative of one or both of a change in head-medium spacing and head-medium contact. Each of the sensors may have a TCR with the same sign (positive or negative) or each sensor may have a TCR with a different sign.

Abstract: According to one embodiment, a data decoding control apparatus includes a reading controller and a decoding controller. The reading controller reads the encoded data of a symbol unit bit by bit from a storage medium. The decoding controller computes a log-likelihood ratio (LLR) value of the symbol unit for estimate decoding calculation relative to the encoded data based on the number of bit inversion in a symbol of the encoded data and a correction factor.

Abstract: In one embodiment, a tape drive system includes a soft detector having logic configured to execute a first forward loop of a detection algorithm on a first block of signal samples during a first time interval, execute a first reverse loop of the detection algorithm on the first block of signal samples during a second time interval, execute a second reverse loop of the detection algorithm on the first block of signal samples during a fifth time interval, and execute a second forward loop of the detection algorithm on the first block of signal samples during a fourth time interval using second soft information. Other tape drive systems and computer program products for decoding data are presented in more embodiments.

Abstract: A system and method for suppressing jitter in a digital data signal in a signal processor system. The digital data signal has spaced apart byte allocation units wherein such spacing is increased such that unallocated bytes can be identified and removed from the digital data signal. The byte allocation units of the digital data signal are suppressed with a digital data signal being outputted from the signal processor system having suppressed byte allocation units to suppress the occurrence of jitter.

Abstract: In one embodiment, a system includes a robotic accessor for transporting media between multiple storage slots and one or more data storage drives; a controller for controlling the robotic accessor; a memory in communication with and/or integrated with the controller for storing information about the media and the storage slots, the information including data corresponding to a physical distribution of the media in the storage slots; and logic integrated with and/or executable by the controller, the logic being adapted to: position the robotic accessor at a computed optimal position during an idle period of the robotic accessor, the computed optimal position being based at least in part on the physical distribution of the media in the storage slots.

Abstract: Various embodiments concern a dual stage actuation flexure. The dual stage actuation flexure comprises a flexure having a gimbal. The gimbal comprising a pair of spring arms, a tongue between the spring arms, and a pair of linkages respectively connecting the pair of spring arms to the tongue. The dual stage actuation flexure further comprises a pair of motors mounted on the gimbal and a pair of stiffeners respectively mounted on the motors. The dual stage actuation flexure further comprises a slider mounting. Electrical activation of the motors bends the pair of linkages to move the slider mounting about a tracking axis while the stiffeners limit the degree of bending of the motors during the electrical activation.

Abstract: Embodiments of the invention relate to electrostatic discharge (ESD) protection. One embodiment includes a first dissipative adhesive (DA) connected to at least a portion of multiple leads in a first plane of a flexible cable in a coverage area for providing ESD protection to at least one element of an electronic device. A common bus bar is connected to the leads in a second plane of the flexible cable. Conductivity of the common bus bar is greater than conductivity of the first DA and the first plane and the second plane are different planes of the flexible cable.

Abstract: In a power converter, a driver that drives, according to a control signal, a switching element of a switch circuit for converting input power to output power. The control signal represents how to drive the switching element. A controller outputs the control signal to the driver for controlling the driver. A measuring unit measures a value of input power input to the switch circuit. A protection determining unit determines, based on the measured value of the input power, whether there is a need to protect the power converter. The protection determining unit outputs a stop control signal to at least one of the driver and the controller based on a result of the determination of whether there is a need to protect the power converter. The stop control signal represents whether to forcibly stop drive of the switching element.

Abstract: A self-testing fault detector having a line side and a load side and a conductive path there between is provided. The self-testing fault detector includes an auto-monitoring circuit electrically coupled to a fault detection circuit and an interrupting device and it continuously monitors one or more signals to determine an operating state of the fault detector. At least one of the monitored signals includes a fault detection signal, wherein if said automonitoring circuit determines that the fault detection circuit is not properly driving the interrupting device, the automonitoring device converts an input-output port receiving the fault detection signal from an input to an output and drives the interrupting device into a tripped condition using the input-output port.

Abstract: The electric-vehicular charge and discharge device of the present invention includes a power converter, a grounding unit, a ground fault detector, and a switcher. The power converter is interposed between an external circuit and a pair of power terminals of a secondary battery unit of an electric vehicle, and is configured to convert power between the external circuit and the secondary battery unit. The grounding unit connects at least one of the pair of power terminals of the secondary battery unit to a grounding point to be connected to the power converter. The ground fault detector determines whether a ground fault has occurred in a power supply path between the power converter and the secondary battery unit. The switcher separates the secondary battery unit from the power supply path when the ground fault detector determines that a ground fault has occurred in the power supply path.

Abstract: For protecting a photovoltaic generator comprising photovoltaic modules, having an open circuit voltage higher than an insulation design voltage of its photovoltaic modules and being connected to an AC power grid via an inverter against a surge voltage relative to ground resulting from a ground fault and exceeding the insulation design voltage, the photovoltaic generator is surveyed for the occurrence of the ground fault or the surge voltage. Upon the actual occurrence of the ground fault or the surge voltage, at first, the photovoltaic generator is separated from an input-side intermediate link capacitance of the inverter, and the inverter is separated from the AC power grid. Then, the intermediate link capacitance is discharged via a resistor, prior to permanently closing semiconductor switches of an inverter bridge of the inverter and to reconnecting the photovoltaic generator to the input-side intermediate link capacitance of the inverter to short circuit the photovoltaic generator.

Abstract: Protection device structures and related fabrication methods are provided. An exemplary semiconductor protection device includes a first base region of semiconductor material having a first conductivity type, a second base region of semiconductor material having the first conductivity type and a dopant concentration that is less than the first base region, a third base region of semiconductor material having the first conductivity type and a dopant concentration that is greater than the second base region, an emitter region of semiconductor material having a second conductivity type opposite the first conductivity type within the first base region, and a collector region of semiconductor material having the second conductivity type. At least a portion of the second base region resides between the third base region and the first base region and at least a portion of the first base region resides between the emitter region and the collector region.

Abstract: An over-voltage protection device includes a substrate, an insulation layer having a depression over the substrate, a conductor layer having a first electrode and a second electrode over the insulation layer, wherein the first electrode and the second electrode form a discharge path, and the depression is under the discharge path. A method for preparing the over-voltage protection device includes the steps of forming an insulation layer over a substrate; forming a depression in the insulation layer; forming a photoresist pattern filling the depression and protruding the insulation layer; forming a conductor layer over the insulation layer; and removing the photoresist pattern, wherein the photoresist pattern divides the conductor layer into a first electrode and a second electrode that form a discharge path, and the depression is under the discharge path after the removal of the photoresist pattern.

Abstract: Provided is a circuit protection device including a plurality of sheets selectively formed with at least one coil pattern, at least one withdrawal electrode, at least one hole filled with a conductive material, and at least one capacitor electrode and at least two inductors and at least two capacitors, in which the at least one coil pattern forms one inductor and a capacitor is formed between the capacitor electrode and the coil pattern.

Abstract: An overcurrent protection circuit that protects a load from an overcurrent includes: a load current cutoff condition defining unit configured to set two or more load current cutoff conditions in each of which passage of a load current larger than or equal to a specified current for a specified time or longer is set as a condition for cutting off the load current; a detection unit configured to detect passage of the load current larger than or equal to the specified current for the specified time or longer in at least one of the two or more load current cutoff conditions; and a load current cutoff unit configured to cut off the load current when the detection unit detects that at least one of the load current cutoff conditions is satisfied.

Abstract: A battery protection circuit includes a control module, a first switch, and a loading module. The control module includes a second switch. A base terminal of the second switch is connected to a positive terminal of a battery, and an emitter terminal of the second switch is grounded. The first switch includes a gate terminal, a source terminal, and a drain terminal. The gate terminal is connected to the control module and further connected to a collector terminal of the second switch, and the source terminal is grounded. The drain terminal is connected to a first capacitor, and the first capacitor is grounded. The loading module is connected to the battery. When the loading module is abnormal, the gate terminal receives a control signal to switch off the first switch.

Abstract: The present invention pertains to a package module of a battery protection circuit, and the package module of the battery protection circuit according to the present invention comprises: a first internal connection terminal area and a second internal connection terminal area, which are respectively disposed at both edge parts thereof, and in which first and second internal connection terminals connected to a battery can provided with a bare cell are respectively disposed; an external connection terminal area, which is adjacent to the first internal connection terminal area, and in which a plurality of external connection terminals are disposed; and a protection circuit area comprising a device area in which a plurality of passive devices forming the battery protection circuit are disposed and a chip area, which is adjacent to the device area, and in which a protection IC and a dual FET chip forming the battery protection circuit are disposed, are disposed between the external connection terminal area and the

Abstract: To prevent damage on an element even when a voltage high enough to break the element is input. A semiconductor device of the invention operates with a first voltage and includes a protection circuit which changes the value of the first voltage when the absolute value of the first voltage is higher than a reference value. The protection circuit includes: a control signal generation circuit generating a second voltage based on the first voltage and outputting the generated second voltage; and a voltage control circuit. The voltage control circuit includes a transistor which has a source, a drain, and a gate, and which is turned on or off depending on the second voltage input to the gate and thus controls whether the value of the first voltage is changed based on the amount of current flowing between the source and the drain. The transistor also includes an oxide semiconductor layer.