ES2232148T3 - PICTURE REPRESENTATION DEVICE CONTROLLED BY SUBCONS. - Google Patents

Abstract

Imaging device (1, 2) controlled by the pulse width, especially plasma screen, with means (10-13) for the representation of a sequence of images, in which the time interval that is available for a representation of an image is divided into a predetermined number of partial time intervals (t1, ..., t8), the points of the image are associated with the image representation device (1, 2), respectively, of one of two groups of partial times (TG1, TG2), the means (10) establish from an RGB signal an activation sequence that belongs to each point of the image and, therefore, those partial intervals of time (t1,. .., t8) of the partial time groups (TG1, TG2), during which a point of the image is activated, and the image representation device (1, 2) controlled by the width of the imposter has a detector (6a) for motion detection in the sequence of images, characterized in that the means (9, 10) are made for the modification of the sequence of the partial intervals of time (t1, ..., t8) depending on the signals of the detector (6a) and these means ( 9, 10) control the modification of the sequence of the time intervals (t1, ..., t8) depending on the output signal of the detector (6a).

Description

Imaging device controlled by subframes.

The invention relates to a device of image representation controlled by pulse width, especially a plasma screen, with activation means for the activation of a screen with the characteristics indicated in the preamble of claims 1, 2 and 3. Further, the invention refers to a procedure for the activation of a device of representation of images with the characteristics indicated in the preamble of claims 12, 13 and 14.

Such a procedure and a device for these types are used, for example, in plasma screens in color, which will replace in the future the image tubes in color still currently used in television sets of high quality. In relation to the tubes of the color image, the user of high quality television sets is accustomed since the late 80s to a free representation of oscillations under 100 Hz technology.

It is known from the magazine Radio Fernsehen Elektronik RFE, No. 2, 1997, pages 18-20 a plasma screen, which consists of two glass plates with electrodes arranged in matrix form, among which Find a mixture of noble gas. Image information is not represented on plasma screens by lines, as in cathode ray tubes, but for complete images. Since to through the addressing of the matrix of a plasma screen, the individual points of the image cannot be connected and disconnect individually at discretionary times, you must perform the activation of the points of the image for all the screen in a transition of activation.

The activation of a plasma screen is constituted by several phases: an addressing phase or initialization, a retention or activation phase and a phase of erased.

In the addressing phase or of initialization all cells on the screen are preloaded plasma, which must be activated in the next retention phase or of activation. In the last stage, the erase phase, they are downloaded the preloaded cells again and the information in the image.

The time interval that is available for the representation of a television image is broken down into partial time intervals of different duration, during which is selected, depending on the point clarity value respective image, a default activation sequence. This corresponds to a single or multiple point illumination respective image during the time interval that is available for image representation, being associated a default duration of time to each lighting.

Such known plasma screens are distributed in the market by Fujitsu, for example as 42 '' plasma screen.

The purpose of the invention is to indicate a device and a procedure for activating a device of representation of the image controlled by the width of the impulse, which lead to improved image reproduction.

This task is solved through a device with the characteristics of claims 1, 2, 3 and through a procedure with the characteristics of the claims 12, 13, 14. The advantageous configurations of the invention are indicated in the dependent claims.

The invention is based on the recognition that in the case of presence of images that move slowly or fixed, during its representation on a device representation controlled by the pulse width can be produce oscillations, especially in the 50 Hz zone, although for the representation of a complete image in a range of 20 msec time, the frequency of the partial time interval be 400 Hz, for example in the case of using 8 intervals Partial time. The same also applies to systems in the 60 Hz zone. Otherwise, the invention is described with the aid of a 50 Hz system.

Simulations have confirmed that a swing of this type, which can be seen especially in images that move slowly, can be avoided by varying the sequence of partial time intervals and / or their sequence of activation in a certain way. Such a variation It is intended to minimize the oscillation of images that must be represented on the screen.

For the achievement of a representation the most possible free of oscillations, it has been revealed that it is advantageous distribute the activation of partial time intervals of an essentially uniform way.

A generation of different scales is achieved of grays by means of an appropriate selection of the intervals partial time activated.

In the case of the presence of moving images quickly, the sequence of the partial intervals is selected of time and / or its activation sequence so that a representation of the artifacts free image of the movement.

In practical applications it has been shown now that it is advantageous to fix the relationship between the duration of the shorter activation and the longest activation duration in 1: 12. The number of partial time intervals is fixed at 8. Partial time intervals are divided into two groups of part time.

In a preferred embodiment of the invention, a time interval of 20 msec is provided. for the representation of a complete image and, therefore, the sequence of the partial time intervals is 400 Hz.

The corresponding tasks of the control of planned deviation in the tube television sets of the image are performed on the device representing the image controlled by the pulse width such that the activation means for screen activation have a time control facility, which processes synchronized signals vertical and horizontal and that activates the control of the times of the pulse width modulator as well as an installation of horizontal excitation of the plasma screen.

It is described below and explained in detail the invention with the help of the embodiments represented in the figures. In this case:

Figure 1 shows a block diagram of a television receiver with a screen representation of Plasma controlled by pulse width.

Figure 2 shows a representation of a First pattern of partial intervals of time.

Figure 3 shows a diagram, which belongs to pattern of partial time intervals of figure 2 for the illustration of the 50 Hz oscillation.

Figure 4 shows a diagram for the illustration of the distribution of clarity over a period of full image for a special level of the input signal, in the that there are strong oscillations of 50 Hz.

Figure 5 shows an optimized pattern of partial time intervals, in which the 50 Hz oscillation.

Figure 6 shows a diagram, which belongs to pattern of partial time intervals of Figure 5, for the illustration of the reduced oscillation of 50 Hz.

Figure 7 shows a diagram for the illustration of the operation type switching, depending on of the motion detector, for example with two states of functioning.

Figure 1 shows a block diagram of a television receiver with a plasma screen representation controlled by pulse width. The television receiver 1, 2 presents a processing part 1 of television signals and an image processing part 2. The processing part 1 of television signals presents a first input 17, to which the signals of an antenna installation 19 are fed. signals from input 17 are transmitted to a unit of 4 high frequency and intermediate frequency processing as well as to an audio signal processing unit 3. In the output of the high frequency processing unit 4 and of intermediate frequency is an FBAS signal, which is fed to an analog / digital converter. The feeding of a signal External FBAS is possible through a second signal input 20. The output signal of the analog / digital converter 5 is then led to a so-called benefit box 6. The benefits box 6 performs certain functions such as demodulation of the FBAS signal, still image, Zoom, adaptation of the format, image sharpness optimization, image - in - image, etc. The digital components Y, U, V that are obtained from this way a signal from image 21 is transmitted to a digital matrix unit 8 of the processing part of the image 2. The benefits box 6 also serves to conversion of the line skip signal into a signal free from line break and for the necessary adaptation of the signal to the screen 14 through the interpolation of lines. This leads to out with the help of synchronization signals 23, 24 for the vertical and horizontal synchronization.

The digital matrix unit 8 presents, in addition, a connection 27 for feeding a VGA signal fed through an external signal input 18, which is converted by means of an analog / digital converter 25 into a digital signal At the output of the digital matrix unit 8, finds an RGB signal 22, with which controller 10 is activated, 13. Controller 10, 13 generates the activation signals 26 for an address excitation circuit 11. For this generation of signals a memory 9 is coupled with controller 10, 13. The controller 10, 13 presents an interval association unit partial time, which is used to set the sequence and the duration of partial time intervals.

The excitation installation of columns 11 activates the individual columns of the plasma screen 14. The Corresponding time control is done with the help of controller 10, 13, which sets the beginning of the intervals Partial times and times for the addressing phase and of activation. The control installation of the lines of the partial intervals of time that is contained in The control of the times. The controller 10, 13 is connected to a horizontal excitation circuit 12. This excitation circuit horizontal 12 is active during the activation phases. The voltage supply is done with the help of a source of feeding 7.

While the operating mode and the structure of the processing part 1 of the signals of television essentially correspond to those of a receiver of Conventional television with image tube, the structure of the Image processing part 2 is basically different. The main reason for this lies primarily in the fact that the installation of plasma representation 14 presents a digital relationship between the magnitude of the input and the density of light. Thus, There are only two states: connected or disconnected. Without However, in order to achieve a wide range of gray scales different intermediates, it is used in the processing part of the image 2 represented in figure 1 for the representation of the image a digital multiple access procedure by division of weather. In this procedure, the RGB 22 signals are broken down into several partial time intervals of different duration. This is carried out with the help of controller 10, 13 as well as by of other units, such as a memory 9. Due to the inertia of the eye human, no longer appear in the plasma rendering facility 14 individual image changes, but a gray value, which It depends on the average duration of activation. If this duration is weighted at partial time intervals, then you can represent with few partial intervals of time many scales of gray. In the case of a binary weighting 1, 2, 4, 8, ... they can represent two gray scales enhanced with a number of partial intervals of time. To be able to represent in greater possible number of gray scales, it is desirable, therefore, use as many partial intervals as possible, which is not possible, however, under the conditions technological marginals. The controller 10, 13 determines through an association, which depends on its level of the input signal, the sequence and activation of partial time intervals individual. In the case of a binary weighting, this association appears in such a way that it is assigned to the most weighted digital bit significant the longest partial time interval, and to bit weighted as the second most significant the partial interval of Second longest time and so on.

The image rendering device controlled by the pulse width presents a digital matrix (8), which is intended for the processing of a digital signal of the image (21, 27) and which provides the signal as output signal RGB fed to the pulse width modulator (10) of the activation means (10-13).

Simulations and subjective considerations have shown that despite a frequency of intervals partial time of 400 Hz, may appear with the effect of interference oscillating artifacts of 50 Hz, especially from of medium densities of light. The incidence of the swing of 50 Hz varies in this case with the density of the light to represent and depends on the level of light density of the partial interval of time activated in each case as well as the sequence of the partial time intervals within the 20-frame period msec

The image rendering device controlled by the pulse width presents a digital matrix (8), which is intended for the processing of a digital signal of the image (21, 27) and which provides the signal as output signal RGB fed to the pulse width modulator (10) of the activation means (10-13).

For this reason, controller 10, 13 is activated of the device for representing image 2 in such a way that the sequence of the partial intervals of time and its activation sequence depending on the content of the movement of The signal of the image. In a working state, when they are present fast movements, a representation is carried out correct movement of the signals represented on the screen and in a state of operation with slow movements it leads to Make a representation of the image free of oscillations.

Figure 2 shows a representation of a diagram of a pattern of partial intervals of time, in which the images represented are represented in a correct way As for the movement. In this case, the letter L is identified The input level of the RGB signal light density designated in figure 1 with reference number 22. The groups of partial times TG1 and TG2 are characteristic for a Image representation The elements of the image of the Plasma screen are associated with one of two groups of partial times TG1 or TG2. Image formation is done in each case in several partial intervals of time t1 to t8 consecutive in time. The light density signal L, which is associated to a respective point of the image, you get to from the analog value of clarity through the scheme of activation, according to figure 2 and from the sequence of activation that results from it. The relationship between the duration plus short activation and longer activation duration is in a ratio of 1 to 12. The number of durations of the activation generated at partial time intervals t1 to t8 it is 12 in the embodiment shown in figure 2. The number of partial time intervals t1 to t8 is 8. The duration of activation of the partial time groups TG1 and TG2 is identical.

The length of time of the partial intervals of time t1 to t8 that different, which is expressed in figure 2 by means of the "weighting factors" 12, 8, 4, 2 and 1 indicated on the bottom side of the diagram.

If you present, for example, the input level of the density of light L, which is associated with a point in the image of the plasma screen 14, the value 44, then this point of the image lights up during partial time intervals t1, t2, t3, t7 and t8 of the partial time group TG1 and during the partial time intervals t1, t2, t6, t7 and t8 of the second group of partial times TG2 and darkens during intervals partial time t4, t5 and t6 of the first time group partial TG1 and during partial time intervals t3, t4 and t5 of the second group of partial times TG2.

Figure 3 shows a diagram, which belongs to pattern of partial intervals of time in Figure 2, for the illustration of a 50 Hz oscillation as a function of clarity H and of the level of the input signal L. The development of the curve characteristic F, which identifies the 50 Hz oscillation, shows especially at levels of the input signal L> 30 a 50 Hz oscillation that appears amplified. You can verify a maximum under this simulation result with an amplitude of the input signal of 44 as the value of the oscillation Fm.

Figure 4 shows the average clarity curve Hm for a special level of the amplitude of the input signal of 44 as a function of time t. From this clarity curve Hv sinusoidal or cosenoidal can be recognized Clearly the interference of the 50 Hz oscillation.

Figure 5 shows an interval pattern Optimized time partials in relation to the oscillation of 50 Hz. In this case, the reference signs already indicated are used in relation to figure 2. The pattern of partial intervals of time represented in figure 5 presents, as opposed to the pattern represented in figure 2, a modified sequence of partial time intervals t1 to t8. In this way, in the exemplary embodiment depicted in figure 5, the sequence of the weights is 12, 4, 8, 1, 2, 12, 4, 8, while the sequence of the weights in the partial interval pattern of time represented in Figure 2 is 12, 8, 4, 2, 1, 4, 8, 12. The corresponding sequence of partial time intervals in figure 5 it is t1, t3, t2, t5, t4, t8, t6, t7, while the sequence of partial time intervals in figure 2 is t1, t2, t3, t4, t5, t6, t7, t8.

Figure 6 shows the simulation result for the pattern of partial intervals of time represented in t5. In this case, the reference signs already used with relation to figure 3. The simulation shows that the pattern of partial intervals of time represented in figure 5 leads to a clearly reduced 50 Hz oscillation, especially at levels high of the input signal.

Since the 50 Hz oscillation mentioned only appears with interference effect on contents of still images or moving slowly, only used according to the invention the pattern of partial time intervals according to Figure 5 in still image contents or image contents They move slowly. On the other hand, in the case of contents of images that move quickly, the pattern of partial time intervals according to figure 2, in which they appear reduced artifacts of movement.

To this end, the television receiver represented in figure 1 presents as a component of the box performance 6 a motion detector 6a, whose signals of output are fed to controller 10, 13. This controller default in a first operating state, in the case of that there are still images or that move slowly, the sequence of the partial intervals of time and / or the sequence of activation, so that the oscillation of the images represented in representation 14. In addition, predetermined, for example, in a second operating state, in the case of the presence of images that move quickly, the sequence of partial time intervals and / or the sequence of activation of the partial time groups in such a way that minimize motion artifacts in images represented in representation 14.

For the realization of these states of operation, controller 10, 13 accesses data sets that are associated with the content of the respective movement, which they are memorized in different areas of memory 9.

This is illustrated in Figure 7. Figure 7 shows shows that memory 9 has, for example, two memory areas 9a and 9b different. In each of these areas of memory are memorized data, corresponding to the respective pattern of the partial intervals of time. According to the content of the image movement, which is detected by the detector movement 6a, an address of one of the two is carried out memory areas, to read the data belonging to the pattern of partial intervals of time.

An advantageous development of the invention consists of in anticipation, in addition to the two operating states already mentioned, other operating states, where each of these other operating states correspond to a content determined movement. In this case, memory 9 presents other areas of memory, which contain data sets for These other operating states.

In an advantageous configuration of the invention, the controller 10, 13 is realized by means of a modulator of the pulse width 10 and by a time control facility 13.

Claims (14)

1. Image representation device (1, 2) controlled by the pulse width, especially plasma screen, with means (10-13) for the representation of an image sequence, in which the time interval is available for a representation of an image is divided into a predetermined number of partial time intervals (t1, ..., t8), the points of the image are associated with the image representation device (1, 2), respectively, of one of two groups of partial times (TG1, TG2), the means (10) establish from an RGB signal an activation sequence that belongs to each point of the image and, therefore, those partial intervals of time (t1 , ..., t8) of the partial time groups (TG1, TG2), during which a point of the image is activated, and the image representation device (1, 2) controlled by the width of the imposition presents a detector (6a) for motion detection in the sequence of images, characterized in that the means (9, 10) are made for the modification of the sequence of the partial intervals of time (t1, ..., t8) based on signals from the detector (6a) and these means (9, 10) control the modification of the sequence of the time intervals (t1, ..., t8) depending on the output signal of the detector (6a). 2. Image representation device (1, 2) controlled by the pulse width, especially plasma screen, with means (10-13) for the representation of an image sequence, in which the time interval is available for a representation of an image is divided into a predetermined number of partial time intervals (t1, ..., t8), the points of the image are associated with the image representation device (1, 2), respectively, of one of two groups of partial times (TG1, TG2), the means (10) establish from an RGB signal an activation sequence that belongs to each point of the image and, therefore, those partial intervals of time (t1 , ..., t8) of the partial time groups (TG1, TG2), during which a point of the image is activated, and the image representation device (1, 2) controlled by the width of the imposition presents a detector (6a) for motion detection in the sequence of images, characterized in that the means (9, 10) are made for the modification of the sequence of activation of the image points according to the signals of the detector (6a) and these means (9, 10) control the modification of the sequence of activation of the points of the image depending on the output signal of the detector (6a). 3. Image representation device (1, 2) controlled by the pulse width, especially plasma screen, with means (10-13) for the representation of an image sequence, in which the time interval is available for a representation of an image is divided into a predetermined number of partial time intervals (t1, ..., t8), the points of the image are associated with the image representation device (1, 2), respectively, of one of two groups of partial times (TG1, TG2), the means (10) establish from an RGB signal an activation sequence that belongs to each point of the image and, therefore, those partial intervals of time (t1 , ..., t8) of the partial time groups (TG1, TG2), during which a point of the image is activated, and the image representation device (1, 2) controlled by the width of the imposition presents a detector (6a) for motion detection in the sequence of images, characterized in that the means (9, 10) are made for the modification of the sequence of the partial intervals of time (t1, ..., t8) and for the modification of the sequence of activation of the points of the image as a function of detector signals (6a) and the means (9, 10) control the modification of the sequence of the time intervals (t1, ..., t8) as a function of the detector signals (6a) and control the modification of the sequence of activation of the image points according to the detector output signal (6a). 4. Image representation device (1, 2) controlled by the pulse width, according to claim 1 or 3, characterized in that the means (10-13) actuate the image representation device (1, 2) controlled by the width of the pulse in several operating states, being predetermined in a first operating state, in the case of the presence of still images or moving slowly, the sequence of partial time intervals (t1, ..., t8 ) in such a way that the scintillation of images represented on a screen (14) is minimized, and being predetermined in a second operating state, in the case of the presence of rapidly moving images, the sequence of partial intervals of time (t1, ..., t8) in such a way that motion artifacts in images represented on the screen (14) are minimized. 5. Image representation device (1, 2) controlled by the pulse width, according to one of claims 2 or 3, characterized in that the means (10-13) actuate the image representation device (1, 2 ) controlled by the pulse width in several operating states, being predetermined in a first operating state, in the case of the presence of still images or moving slowly, the activation sequence in such a way that scintillation is minimized of images represented on a screen (14), and being predetermined in a second operating state, in the case of the presence of rapidly moving images, the activation sequence in such a way that the movement artifacts in the movement are minimized images represented on the screen (14). 6. Image representation device (1, 2) controlled by the pulse width, according to one of the preceding claims, characterized in that the image representation device (1, 2) controlled by the pulse width has a memory (9) with several memory areas, each memory area being provided for memorizing activation sequences, corresponding to one of the operating states. 7. Image representation device (1, 2) controlled by the pulse width, according to one of the preceding claims, characterized in that the means (10-13) have a controller (10, 13), which is composed of a pulse width modulator (10) and a time control facility (13). 8. Image representation device (1, 2) controlled by the pulse width, according to one of the preceding claims, characterized in that the image representation device (1, 2) controlled by the pulse width has a matrix digital (8), which is intended for the processing of a digital image signal (21, 27) and provides as output signal the RGB signal fed to the pulse width modulator (10) of the activation means (10- 13). 9. Image representation device (1, 2) controlled by the pulse width, according to one of the preceding claims, characterized in that the means (10-13) have a time control installation (13), to which vertical and horizontal signals (23, 24) are fed and it is connected on the output side with the pulse width modulator (10) and with a horizontal excitation circuit (12). 10. Image representation device (1, 2) controlled by the pulse width, according to one of claims 1 or 3 or 5 to 9, characterized in that in the first operating state the sequence of the partial intervals of time in each case in such a way that one of the relations is applied for the duration of the activation of the partial intervals of time t1: t2: t3: t4: t5: t6: t7: t8 = 12: 4: 8: 1: 2: 12: 4: 8 or t1: t2: t3: t4: t5: t6: t7: t8 = 12: 4: 8: 1: 2: 12: 4: 8 11. Image representation device (1, 2) controlled by the pulse width, according to one of claims 1 or 3 or 4 or 6 to 10, characterized in that the sequence of the intervals is selected in the second operating state partial time in each case in such a way that the following relation is applied for the duration of the activation of the partial intervals of time t1: t2: t3: t4: t5: t6: t7: t8 = 12: 8: 4: 2: 1: 4: 8: 12 12. Procedure for the activation of an image representation device (1, 2) controlled by the pulse width for the representation of an image sequence, in which the time interval that is available for a representation of an image it is divided into several partial time intervals (t1, ..., t8) consecutive in time and the image points of the image representation device (1, 2) controlled by the pulse width are divided into two groups of partial times (TG1, TG2), the clarity signal associated to a point of the image being generated from an RGB signal through an activation scheme and from an activation sequence derived from it, indicating during which Partial time intervals (t1, ..., t8) the image point is activated, characterized in that the sequence of partial time intervals (t1, ..., t8) is modified depending on the content of the movement of the image. sequel of images to represent. 13. Procedure for the activation of an image representation device (1, 2) controlled by the pulse width for the representation of an image sequence, in which the time interval that is available for a representation of an image it is divided into several partial time intervals (t1, ..., t8) consecutive in time and the image points of the image representation device (1, 2) controlled by the pulse width are divided into two groups of partial times (TG1, TG2), the clarity signal associated to a point of the image being generated from an RGB signal through an activation scheme and from an activation sequence derived from it, indicating during which Partial time intervals (t1, ..., t8) the image point is activated, characterized in that the activation sequence is modified according to the content of the movement of the sequence of images to be represented. 14. Procedure for the activation of an image representation device (1, 2) controlled by the pulse width for the representation of an image sequence, in which the time interval that is available for a representation of an image it is divided into several partial time intervals (t1, ..., t8) consecutive in time and the image points of the image representation device (1, 2) controlled by the pulse width are divided into two groups of partial times (TG1, TG2), the clarity signal associated to a point of the image being generated from an RGB signal through an activation scheme and from an activation sequence derived from it, indicating during which Partial time intervals (t1, ..., t8) the image point is activated, characterized in that the sequence of the partial time intervals (t1, ..., t8) and the activation sequence are modified depending on the content or of the movement of the sequence of images to represent.