Abstract: In various embodiments, the present disclosure provides a wall panel blocking bracket including a first base, a first stud side engager connected to and extending upwardly from the first base, a second stud side engager connected to and extending upwardly from the first base, a second base connected to the first stud side engager, a third base connected to the second stud side engager, a first hook extending transversely from the first stud side engager, a second hook extending transversely from the second stud side engager, all configured to partially support a wooden block adjacent to a support beam in any one of a perpendicular orientation, a first position parallel orientation, and a second different position parallel orientation.

Abstract: The present invention relates to a touch technology and provides a capacitive touch panel which has low-visibility metal jumper. The touch panel comprises of a transparent substrate and at least one metal juniper. A mask layer, reflectance of which is lower than that of the metal jumper, is set between the metal jumper and the transparent substrate to block the light reflected by the metal jumper. The mask layer can reduce light reflection of the metal jumper so as to reduce visibility of the metal jumper.

Abstract: An ultrasonic device includes an ultrasonic element group, a first to an Nth driving electrode lines, first and second terminals. The ultrasonic element group includes a plurality of ultrasonic elements forming “N” columns arranged along a second direction intersecting with a first direction with each of the “N” columns including a plurality of the ultrasonic elements arranged along the first direction, “N” being a natural number that is equal to or more than 2. The first to the Nth driving electrode lines are arranged along the first direction. An ith driving electrode line is connected to the ultrasonic elements constituting an ith column among the “N” columns, with “i” being a natural number equal to or less than “N”. The first terminal is connected to one end of the ith driving electrode line, and the second terminal is connected to the other end of the ith driving electrode line.

Abstract: A display device having a plasma display panel may include a plasma display panel which includes a plurality of electrodes and a driver which supplies a driving signal to the plurality of electrodes. The driving signal having a driving waveform may include a resetting section and an addressing section and include a plurality of pulses applied between the resetting section and the addressing section.

Abstract: One or more implementations access a digital image containing one or more bands. Adjacent bands of the one or more bands have a difference in color resulting in a contour between the adjacent bands. The one or more implementations apply an algorithm to at least a portion of the digital image for reducing visibility of a contour. The algorithm is based on a value representing the fraction of pixels in a region of the digital image having a particular color value.

Abstract: Luminous elements of the three colors red, green and blue of video display devices have a different response time. Therefore, a colored edge and trail appear at edges in direction of a moving object. In order to reduce the disturbing character of such colored edges and trails, a horizontal spatial equalization of the response time of luminous elements having a shorter response time by low-pass filtering a component signal of the video component signals for driving luminous elements having a shorter response time dependent on a horizontal speed of changes of the component signal is recommended to reduce phosphor lag artifacts on display devices. The arrangement for processing video component signals of different color comprises a compensation unit which according to a preferred embodiment is realized by a FIR filter and a horizontal speed correction unit supplied with a horizontal and vertical motion estimation signal.

Abstract: A lighting device includes a cold cathode fluorescent tube (CCFT), a chassis housing the CCFT, and a lamp clip. The chassis includes at least three mounting through holes at least one of which is arranged on a first line and a second line. The first line and the second line are separately extending in a direction substantially perpendicular to an axial direction of the CCFT, whereby the mounting through holes are asymmetrically arranged. The lamp clip includes a main body, a lamp gripping portion capable of gripping the CCFT, and at least three mounting portions protruding from the main body. At least one of the mounting portions is each arranged on the first line and the second line, whereby the mounting portions are asymmetrically arranged. The mounting portions on the first and second lines are passed through the mounting through holes on the first and second lines, respectively.

Abstract: A picture quality when reducing the brightness or the contrast of the picture on a plasma panel shall be improved. For this purpose there is provided a driving apparatus including brightness/contrast control means for receiving video input data for modifying the video levels of the video input data in accordance with external adjustment data and for outputting modified video data. First power measurement means measure a power level of the modified video data and supply a first power level. Second power measurement means measure a power level of the video input data and supply a second power level. Generator means generate a third power level comprised between the first power level and the second power level or equal to the larger one to data processing means. The data processing means calculate the maximum number of sustain pulses per frame applicable to the modified video data on the basis of the third power level and control the display of the modified video data on the plasma display panel.

Abstract: An inputted picture signal is stored in an image memory into which a picture signal for at least one frame period can be written, while rewriting the memory. At a plurality of timings within one frame period, an average brightness calculation unit calculates an average brightness from the picture signal written into the image memory, and a brightness control unit performs brightness control of the picture signal read from the image memory based on the calculated average brightness.

Abstract: Systems and methods for measuring spatial and angular performance of a visual display are disclosed herein. In one particular embodiment, for example, a method for measuring spatial and angular performance of a flat panel visual display includes capturing a plurality of image measurements from a visual display at a plurality of different view angles. The method also includes selecting one or more points of interest on the visual display, and calculating tristimulus values (X, Y, Z) for each point of interest at each of the plurality of view angles. The method further includes generating a view angle performance plot for the one or more selected points of interest.

Abstract: A panel-type television whose colors and image qualities of OSD portions are kept intact and the qualities of images other than the OSD portions are adjusted is provided. The panel-type television includes an image quality adjustment circuit 30a that performs a specified image quality adjustment processing on input image signals; a delay circuit 30b that delays input image signals by the time needed for the image quality adjustment circuit 30a to perform image quality adjustment processing; and a switching 30c that switches between the image quality adjustment circuit 30a and the delay circuit 30b so that image signals are input to either of the circuits according to the control of a microcomputer 60, wherein the microcomputer 60 inputs image signals for OSD display areas to the delay circuit 30c and image signals other than those for OSD display areas to the image quality adjustment circuit 30a.

Abstract: The invention relates to a method for processing video pictures, the video pictures consisting of pixels digitally coded, the digital code word determining the length of the time period during which the corresponding pixel of a display is activated, wherein to each bit of a digital code word a certain activation duration called sub-field is assigned, the sum of the duration of the sub-fields according to a given code word determining the length of the time period during which the corresponding pixel is activated, said method comprising the following steps: detecting the video pictures source mode and the parity between pictures, if the source is in film mode, distributing the total number of sub-fields used for two frame raster in three groups of sub-fields and assigning to a value of a pixel a code word that corresponds to the distribution of the active sub-fields period over the three sub-fields groups, and if the source is in camera mode, distributing the total number of sub-fields used for each frame r

Abstract: A method for generating a video clock and an associated target image frame is disclosed. The method generates an output clock signal for outputting a target image frame to a panel according to a frame pixel number and a vertical synchronization signal (Vsync). The target image frame corresponds to a source image frame. The frame pixel number is the number of total pixels included in a predetermined frame format, and the Vsync signal is an input Vsync signal or an output Vsync signal. The period of the output clock signal is the result of the period of the Vsync divided by the frame pixel number. In this manner, the format of the target image frame can remain substantially fixed, and is substantially equal to the predetermined frame format.

Abstract: The invention deals with the large area flicker effect reduction in display devices like plasma display panels, in which the light output is controlled by small pulses over a whole frame period and the amount of small pulses determine the brightness of the light output. The invention proposes an adaptation of the known principle of sub-field grouping for large area flicker reduction for the specific sub-field coding process called incremental sub-field coding, in which only those sub-field code words are taken for display driving having the characteristic that there is never a sub-field inactivated between two activated sub-fields or never a sub-field is activated between two inactivated sub-fields. For this specific sub-field coding it is proposed to make the sub-field grouping in a simple manner, where all the odd sub-fields are grouped together in one group (G1) and all the even sub-fields are grouped together in a second group (G2).

Abstract: An encoder/decoder uses “self-referencing” frames. For example, a second B-field in a current frame references the first B-field from the current frame in motion compensated prediction. Allowing the first B-field in a frame to act as a reference for the second B-field in the frame allows more accurate prediction of the second B-field, while also preserving the temporal scalability benefits of having B-fields in the current frame.

Abstract: When showing a picture without trimming it while a video signal stored in a frame memory 26 has an aspect ratio different from that of a screen of a plasma display panel 29, with respect to video signals E2a and E2b in areas bordering on blank zones E1 and E3 containing no picture appearing in upper and lower or right and left ends of the screen of the plasma display panel 29, a video signal processor 23 reduces a luminance difference by lowering levels of overshoots 30a and 30b and undershoots 30c and 30d accompanying sharpness processing applied to cope with blurring in edge portions caused by bilinear interpolation, thereby suppresses burn-in of the video signals E2a and E2b in said areas bordering on the blank zones on the plasma display panel 29.

Abstract: A panel driving method in which a single TV field includes at least one reset period and at least one subfield and each of the at least one subfields includes an address period and a sustain period, includes supplying a variable reset pulse according to the length of a pause period in a previous or present TV field. A variable reset period is supplied according to the length of a pause period in a single TV field, so that a reset operation for preparing the address period is stably performed.

Abstract: In an image display apparatus, a video signal is divided for each field into a plurality of sub-fields, each of which is weighted according to the duration of time or number of pulses. The plurality of sub-fields are temporally superimposed for display, so that a grayscale representation is provided. A video signal for the current field is delayed by one field, and output as a video signal for the previous field. Based on the video signal for the current field and the video signal for the previous field, a luminance gradient of an image is detected. A difference between the video signal for the current field and the video signal for the previous field is calculated. Based on the calculated difference and the detected gradient, the amount of motion of the image is calculated by a detecting circuit. Based on the calculated amount of motion of the image, dynamic false contours are reduced by an image data processing circuit.

Abstract: Conventionally, it was difficult to maintain parallelism between an optical filter and a PDP, and also the weight of the optical filter was put on the PDP. With a PDP 10 and a frame 30 separately fixed to a bracket 20 connecting to a leg member 60, fix an optical filter 80 to the frame 30. As a result, the optical filter 80 is fixed with required parallelism maintained with the PDP 10, and also the optical filter 80 and the PDP 10 will not put their weight on each other, thus eliminating unnecessary loads on the optical filter 80 and the PDP 10. Also, unnecessary flaws and distortions in a casing 40 can be prevented during the product manufacturing.

Abstract: The gradation display device contains gradient detecting circuit (3) for detecting a gradient of gradation values of pixels in an incoming image; time-varying gradation-value detecting circuit (4) for detecting changes in gradation values of the pixels with a passage of time; an image detector for detecting a magnitude and a direction of movement of the incoming image according to outputs from gradient detecting circuit (3) and time-varying gradation-value detecting circuit (4); and gradation correcting circuit (12) for correcting signals of the incoming image according to the detected magnitude and direction of the image and the weight of luminance assigned to each of the sub-fields so as to display proper image.

Abstract: A display apparatus to receive a picture signal containing information of a picture and to process the picture signal using at least an area distinguishing the picture from another picture includes a motion detector to detect whether there is a motion in the area of the picture signal, a hysteresis generator to output hysteresis information on each area according to a detected result of the motion detector from a previous frame up to a current frame, a moving picture detector to detect whether the picture signal is a moving picture signal or a still picture signal in the area on the basis of the hysteresis information, and a gradation level converter to convert the picture signal corresponding to the area into either a group of gradation levels for a moving picture to display the moving picture signal or a group of gradation levels for a still picture to display the still picture signal according to a detecting result of the moving picture detector.

Abstract: The invention relates to a method for processing video pictures for display on a display device having a plurality of luminous elements corresponding to the pixels of a picture wherein the time of a video frame or field is divided into a plurality of N sub-fields during which the luminous elements can be activated for light emission in small pulses corresponding to a sub-field code word of n bits used for coding the p possible video levels lighting a pixel, comprising the steps of: determining if pictures are static pictures or moving pictures, in case of static pictures, processing video pictures using a first sub-field encoding method adapted to pictures when no motion is detected, and in case of moving pictures, processing video pictures using a second encoding method reducing dynamic false contour effect adapted to pictures when motion is detected. The invention applies to plasma display panels.

Abstract: A method and apparatus for reducing flicker when displaying pictures on a plasma display panel, based on an input phase alternation line (PAL) video signal of 50 Hz. Video signal data include successive first and second sub-field groups. When the number of sub-fields in the first sub-field group is more than that of sub-fields in the second sub-field group, the start or end points of the first and second sub-field groups are fixed, based on whether the video signal has a load ratio higher than a threshold value. When the number of sub-fields in the first sub-field group is less than that of sub-fields in the second sub-field group, the start or end points of the first and second sub-field groups are fixed, based on whether the video signal has a load ratio higher than a threshold value.

Abstract: The luminous elements of the three colours red, green and blue of a plasma video display have different time responses. Therefore, a coloured trail/edge appears behind and in front of the edges of a moving object. In order to reduce the disturbing character of such coloured trails/edges, correcting the video data for blue and red phosphor elements to compensate for the different time responses discolor them. Then only a discolored trail/edge appears which is less disturbing.

Abstract: The invention is related to a new kind of plasma display panel control. A known principle for PDP control is based on a combination of sub-field addressing and priming. Within the priming period all the plasma cells of the panel are pre-excited by a strong voltage pulse. This treatment of the cells produces a slight background luminance which is a drawback for picture quality aspects because the achievable contrast is reduced. According to the invention it is proposed to use self-priming sub-fields and refreshing sub-fields instead of this hard priming period. With these concepts it is assured that the cells which ought to be black remain black. Self-priming sub-fields reduce or eliminate the need for priming, thus making dark areas darker, while refreshing sub-fields, can be addressed faster. In practice, the number of refreshing sub-fields in a frame period is higher than the number of the self-priming sub-fields. Therefore, the total addressing time can be reduced with this new technique.

Abstract: The differences between the time responses of phosphor elements of a plasma display panel (17) shall be reduced by signal processing means without a need of a motion estimator. Therefore, the sub-fields for driving the luminous elements are reorganized in at least two groups of sub-fields arranged one after the other within one frame period. Luminous elements with long time responses are driven by the sub-fields of the first group and luminous elements with short time responses are driven by sub-fields of the first and second group. Thus, the phosphor lag effects are reduced.

Abstract: The object of the invention is to provide a method for driving a plasma display panel that provides an improved expression of levels of halftone as well as an improved display quality. In N sub-fields constituting a display period of one field, when a pixel data writing step for setting discharge cells to either one of non-light-emitting cells or light-emitting cells in response to pixel data and a light-emission sustaining step for allowing only the aforementioned light-emitting cells to emit light only during a light-emission period corresponding to weights assigned to the sub-fields respectively are executed, the light-emission period in the light-emission sustaining step of the respective sub-fields is changed field by field or frame by frame. According to another aspect, the invention allows for carrying out selectively a first drive pattern or a second drive pattern.

Abstract: A method for operating a liquid crystal display having a panel with a back light includes applying a first gate signal starting a real data period followed by a second gate signal starting a black data period sequentially to gate lines of the panel, applying actual picture data signals to data lines of the panel during the real data period and reset data signals to the data lines of the panel during the black data period to drive cells of the panel during a frame along a gate line and controlling a ratio of the real data period to the black data period for a subsequent frame.

Abstract: A driving method enables an improvement in emission efficiency and achievement of a higher degree of brightness when employing the address while display driving (AWD) scheme. Taking a 3-bit 8-gradation display as an example, a first H period (one horizontal scan period) of each subfield is divided into 3 regions (first region, second region, and third region in the order of time), and, in each of the lines, an address period (address pulse PA and scan pulse PAY) of the subfield SF1 is set in the first region, an address period of subfield SF2 is set in the second region, and an address period of the subfield SF3 is set in the third region. The regions other than those in which the address period is set are used as the sustain period, and a time length of each sustain pulse Ps is set to ? of the length of the H period. A reset period achieved by a reset pulse PR and a priming period achieved by a priming pulse PP are set in the region where the address period is set.

Abstract: An image display unit (100) displays an image on a display device (406), like a plasma display panel, in a number of sub-fields (204-218). The image display unit can perform motion compensation to reduce motion artifacts. This motion compensation is performed by applying a spatial offset to the sub-fields. The image display unit is designed to perform the operations for motion compensation on operands with various granularity, with the granularity of the operands ranging from one sub-field individually to a group of sub-fields together. An embodiment of the image display unit includes an analyzer (110) for estimating the available capacity of a computing unit (108) in a predetermined period of time, in order to determine the granularity of the operands to perform the operations for motion compensation.

Abstract: A device for subfield coding a large-screen display generates a digital value for a picture element of the display, and determines a first number and a second number of subfields of a predetermined total number of subfields from the digital value, for which determined subfields the picture element emits radiation. In order to improve the dynamic range while maintaining the maximally obtainable brightness, the first number of subfields each have a different on-period during which the picture element emits radiation, and the second number of each have a same on-period during which the picture element emits radiation.

Abstract: Plasma Display Panels (PDP) are becoming more and more interesting for TV technology. Due to the larger size of PDPs, with larger viewing angle the large area flicker effect will become more serious in the future, in particular when handling 50 Hz video standards.

Abstract: The invention relates to a method and a device for improving the grey scale resolution of a pulse width modulated image display device. The time interval available for representing an image is divided into successive weighted partial time intervals comprising partial time intervals having low weighting and partial time intervals having high weighting. If the evaluation of the luminosity of the image to be represented causes a dark image to be detected, partial time intervals having high weighting are not required and the number of partial time intervals having low weightings is increased by using additional partial time intervals having low weightings. The weightings of the additional partial time intervals are different to the weightings of the first partial time intervals having low weightings. The grey scale resolution is thereby improved for dark images.

Abstract: A method and apparatus for removing false contours in a pulse number modulation (PNM) digital display device having a plasma display panel (PDP). The method involves a) comparing the input data with the comparison data and calculating a plurality of possible output data in consideration of an index error between the input data and error-diffused input data so that the false contours can be removed, the error-diffused input data being obtained by diffusing a quantization error that has occurred in pixels adjacent to the input data in the current frame; b) detecting an index error between the input data and the error-diffused input data; and c) selecting one from among the plurality of possible output data obtained in step a) in consideration of the index error detected in step b).

Abstract: The object of the invention is to provide a system for encoding grey levels which makes it possible to reduce the problems of contouring by increasing the number of subscans using subscans common to several rows, thereby remedying the error due to the difference between the grey levels of simultaneously scanned cells. The invention provides a method and a device which make row groupings dynamically according to the content of the image.

Abstract: The invention relates to a method for processing data of video pictures for displaying the pictures on a display device like a Plasma Display Panel. The existing false contour effect compensation methods which make a false contour compensation based on shifting sub-field code word entries along the direction of the motion vector of a current pixel, produce an artifact in the pictures, in case of object crossings. In the appearing area there is a lack of light generation.

Abstract: Since the phosphor lag effect results from the slowness of the green and red phosphors and since it is not possible to make these phosphors faster, the blue one has to be made slower in order to reduce the color trail effect. Therefore, a part of the blue component is artificially delayed. Only a certain percentage of the blue component of the actual frame is transmitted during the actual frame, whereas the rest of the blue component will be transmitted during the next frames. The dynamic false contour effect introduced by this video processing may be compensated by subfield shifting.

Abstract: In a method of driving a subfield-driven display (PDP), for a position in a subfield it is examined (E) whether a motion vector for the position differs from a motion vector for a neighboring position to determine whether uncovering or covering is present. If uncovering or covering is present, a size of an area of covering and uncovering is calculated (C), and the area of covering and uncovering is filled (F) in.

Abstract: A plasma-addressed liquid crystal display device capable of high-speed drive and improved viewing characteristic is composed of a liquid crystal cell structure and plasma cell structure stacked with each other. The liquid crystal cell structure is formed by sandwiching a liquid crystal having a spontaneous polarization between a first transparent substrate having therein transparent electrode stripes and an alignment film covering the electrode stripes, and a dielectric sheet having thereon an alignment film. The plasma cell structure is formed of a second transparent substrate having thereon cathode stripes and anode stripes disposed alternately with a spacing therebetween, stacked via stripe-shaped partitions disposed along the anode stripes onto the dielectric sheet so as to form plasma channels between the partitions filled with an ionizable gas sealed up therein.

Abstract: The invention is related two a new kind of plasma display panel control. A known principle for PDP control is based on a combination of sub-field addressing and priming. Within the priming period all the plasma cells of the panel are pre-excited by a strong voltage pulse. This treatment of the cells produces a slight background luminance which is a drawback for picture quality aspects because the achievable contrast is reduced. According to the invention it is proposed to use self-priming sub-fields (SPSF) and refreshing sub-fields (RSF) instead of this hard priming period. With these concept it is assured that the cells which ought to be black remain black. Self-priming sub-fields (SPSF) reduce or eliminate the need for priming, thus making dark areas darker, while refreshing sub-fields (RSF), can be addressed faster. In practice, the number of refreshing sub-fields (RSF) in a frame period is higher than the number of the self-priming sub-fields (SPSF).

Abstract: An image display unit (100) displays an image on a display device (406) like a plasma display panel in a number of sub-fields (204-218). The image display unit can perform motion compensation to reduce motion artifacts. This motion compensation is performed by applying a spatial offset to the sub-fields. The image display unit is designed to perform the operations for motion compensation on operands with various granularity, with the granularity of the operands ranging from one sub-field individually to a group of sub-fields together. An embodiment of the image display unit comprises an analyzer (110) to estimate the available capacity of computing means (108) in a predetermined period of time, in order to determine the granularity of the operands to perform the operations for motion compensation.

Abstract: A plasma display is provided with a plasma display panel, data drivers which apply data pulse to data electrodes of the plasma display panel, a control circuit which t controls an operation of the data drivers based on a video signal, and a protection signal output circuit. The protection signal output circuit outputs a protection signal to the control circuit when sum of currents supplied from the data drivers to the data electrodes within a time equal to one sub-field or more to less than one frame exceeds a previously set first specified current value. The protection signal restrains the operation of the data drivers.

Abstract: In the liquid crystal display, a first backlight and a second backlight are provided and lightened simultaneously. Among all the lamps constituting the backlight, those lamps outputting oscillation waves in one phase are made equal or nearly equal in number to those lamps outputting oscillation waves in the phase opposite to the phase mentioned above.

Abstract: An infrared remote control device used for a plasma display device in which a light-reception signal is obtained by reception of infrared rays, the light-reception signal is demodulated, a signal component during an emission sustaining period is removed from the modulated output signal by a gate circuit, the output signal is output, the output signal of the gate circuit is delayed by a delaying circuit in the field, the logical sum of the output signal of the gate circuit and the output signal of the delaying circuit is calculated, and the contents of the remote control signal that controls the operation of the plasma display device are judged in accordance with a signal obtained by the calculation of the logical sum.

Abstract: A method of driving a plasma display panel which prevents a burning phenomenon when a still image is displayed. A plasma display device includes a plurality of row electrodes formed in pairs corresponding to each display line, a plurality of column electrodes arranged to cross the row electrodes to form a discharge cell corresponding to one pixel at each intersection with a pair of the row electrodes, and a driving controller for controlling driving of the row electrodes and the column electrodes. A gradation display of input pixel data is performed by dividing one field display period into a plurality of subfields. The driving controller, when one field of input pixel data is displayed, changes the number of reset discharges for initializing all discharge cells depending on whether an image to be displayed is a still image or a moving image.

Abstract: A tone display method for displaying a tone of an image in a display system which divides a time width of a field of an image signal into a plurality of weighted subfields and controls operation of the subfields.

Abstract: LC display device based on “plane switching”, in which the switching speed is increased by overdriving the pixels upon a change of the voltage across these pixels while taking, for example, the hydrodynamical properties of the LC material into account. The correction means may also correct for changes of ambient or liquid temperature.

Abstract: A method for displaying an image with gradation and a high brightness with a plasma display panel is provided. In this method, one field is divided into eight subfields, and each subfield is divided into an addressing period and sustaining period. In the upper four bits b4, b5, b6, and b7, in which the sustaining period is long, all of the scanning electrodes are scanned sequentially. In the lower four bits b0, b1, b2 and b3, in which the sustaining period is short, the scanning electrodes are scanned alternately by interlace scanning.

Abstract: A intra-field time division tone display method for dividing the time width in a field of a TV signal into a plurality of subfields in the pixel storing time direction and displaying the TV image by controlling the presence or absence of light emission of the subfields and an apparatus therefor, wherein there are at least two subfields (most significant subfields) whose luminant time widths are longest and almost equal and when it is assumed that the tones are displayed in the ascending order starting from the lowest level of tone in light emission of the subfields, the tone of a TV image signal is displayed under a rule that two or more light emissions are not started from the aforementioned at least two most significant subfields at the same time, accordingly the dynamic false contour noise of a moving image followed by movement of the viewing point can be reduced remarkably and a moving image of high image quality and high quality can be obtained.

Abstract: A method and an apparatus for control a timing in a flat panel display system are disclosed. In an alternating current plasma display system for respectively driving a plurality of subfields at every field in three steps such as a) entering and for eliminating a whole pixel for a first predetermined time, b) entering data for a second predetermined time and c) maintaining a discharge at every subfield for times which are different from one another, a first clock generator generates a first clock signal having a high frequency. A second clock generator generates a second clock signal having a low frequency. A first counter counts the second clock signal in response to a vertical synchronizing signal, and generates both a first pulse signal which sets the first and second predetermined times respectively in steps a) and b) in the respective subfield sections and a second pulse signal which sets times in step c) in the respective subfield sections which are different from one another.