Matrix Type Display Driving System

Owaki , et al. October 22, 1

Patent Grant 3843959

U.S. patent number 3,843,959 [Application Number 05/372,044] was granted by the patent office on 1974-10-22 for matrix type display driving system. This patent grant is currently assigned to Fujitsu Limited. Invention is credited to Hiroshi Furuta, Norihiko Nakayama, Kenichi Owaki, Toshinori Urade.


United States Patent 3,843,959
Owaki ,   et al. October 22, 1974

MATRIX TYPE DISPLAY DRIVING SYSTEM

Abstract

A driving system for matrix type display apparatus having picture elements arranged in a matrix form, each picture element being made up of a plurality of luminous elements of different brightness levels, in which one frame forming one picture is formed with a plurality of fields. Combinations of the luminous elements of adjacent picture elements are altered at every field, and the respective picture elements are scanned in the same manner as that of scanning in television, thus providing a display.


Inventors: Owaki; Kenichi (Kobe, JA), Nakayama; Norihiko (Kobe, JA), Urade; Toshinori (Kobe, JA), Furuta; Hiroshi (Akashi, JA)
Assignee: Fujitsu Limited (Nakahara-ku, Kawasaki, JA)
Family ID: 13209823
Appl. No.: 05/372,044
Filed: June 21, 1973

Foreign Application Priority Data

Jun 22, 1972 [JA] 47-62766
Current U.S. Class: 348/797; 348/E9.012; 348/803
Current CPC Class: H04N 9/12 (20130101)
Current International Class: H04N 9/12 (20060101); H04n 009/30 ()
Field of Search: ;178/5.4EL,7.5D,7.3D,5.4R ;315/169R ;313/18B,18D ;340/146.3MA,166EL,166C,166R ;358/59

References Cited [Referenced By]

U.S. Patent Documents
3790841 February 1974 Tsui
Primary Examiner: Murray; Richard
Assistant Examiner: Godfrey; R. John
Attorney, Agent or Firm: Staas, Halsey & Gable

Claims



What is claimed is:

1. A display system comprising:

a. display device including a plurality of first and second radiation elements for emitting first and second kinds of radiation respectively, said plurality of radiation elements disposed in a matrix of rows and columns so that said first radiation elements are separated from each other along said columns and rows;

b. energizing means for providing energizing signals to be applied to said radiation elements; and

c. control means for applying first the energizing signals to a first field of picture elements, each comprising at least one first radiation element and one second radiation element, and thereafter applying the energizing signals to a second field of different picture elements, each comprised of said one second radiation element and another first radiation element.

2. The display system as claimed in claim 1, wherein said first radiation elements emit a relatively high intensity radiation and said second radiation elements emit a relatively low intensity radiation.

3. The display system as claimed in claim 1, wherein said first radiation elements emit radiation of a first wavelength and said second radiation elements emit radiation of a second, different wavelength.

4. The display system as claimed in claim 1, wherein said display device includes third and fourth radiation elements, said first and second radiation elements emitting radiation of a first color of a first and a second intensity level, respectively, said third and fourth radiation elements emitting radiation of a second, different color of said first and second intensity levels, respectively.

5. The display system as claimed in claim 4, wherein said control means includes a color control circuit responsive to an input information signal for providing first and second color signals indicative of the first and second colors, respectively; first and second decoder circuits responsive respectively to the first and second color signals for each providing outputs indicative of said first and second intensity levels of its respective color; and first and second memory means, said first memory means responsive to said first output of said first decoder circuit and said second output of said second decoder circuit for storing signals indicative of intensity level and color for at least a portion of the picture elements of a first row, said second memory means responsive to the second output of said first decoder and said first output of said second decoder for storing the energizing signals indicative of the color and intensity level for at least a portion of the picture elements of a second row adjacent to said first row.

6. The display system as claimed in claim 1, wherein said display device includes third and forth radiation elements for emitting, respectively, third and fourth kinds of radiation, said first and second radiation elements being arranged alternately along a first column, said third and fourth radiation elements being arranged alternately along a second column adjacent to said first column, said control means comprising row control means responsive to a first field signal for selectively applying the energizing signals to a first and a second row of said radiation elements comprising a single row of said picture elements, and responsive to a second field signal for applying the energizing signal to said second row of radiation elements and a third row of radiation elements adjacent to said second row.

7. The display system as claimed in claim 6, wherein said energizing means is responsive to a video input signal to provide first, second, third and fourth outputs corresponding to the information contained by said video signal for energizing, respectively, said first, second, third and fourth radiation elements, said control means including first and second switch means associated, respectively, with said first and second columns of said display device, said first switch means responsive to first and second timing signals for applying respectively said first and second outputs to said first column, said second switch means responsive to said first and second timing signals for applying said third and fourth outputs, respectively, to said second column.

8. The display system as claimed in claim 1, wherein said display device comprises a plasma display panel including a plurality of X electrodes and a plurality of Y electrodes disposed to intersect each other, and a discharge gas disposed therebetween, whereby a plurality of said radiation emitting elements is formed at the intersecting points of said X and Y electrodes.

9. The display system as claimed in claim 1, wherein said rows of radiation elements are disposed at approximately 45.degree. with respect to said columns of said radiation elements.

10. A method of energizing display apparatus comprised of a plurality of first and second radiation elements for emitting, respectively, first and second kinds of radiation, the plurality of radiation elements disposed in a matrix of rows and columns so that the first and second radiation elements are separated from each other along said columns and rows, said method comprising the steps of:

a. energizing a first field of picture elements, each comprised of one of the first radiation elements and one of the second radiation elements, and

b. energizing a second field of different picture elements, each comprised of the one first element and another of the second radiation elements.

11. The method as claimed in claim 10, wherein in step (a), the one first radiation element and the one second radiation element are disposed respectively upon first and second rows adjacent to each other, and in step (b), the another second radiation element is disposed upon a third row adjacent to the second row, whereby said first and second fields are interlaced with each other.

12. The method as claimed in claim 10, wherein the display apparatus includes first, second, third and fourth radiation elements for emitting different kinds of radiation, the first and second radiation elements arranged alternately in each of the first and third columns of the display apparatus, the third and fourth radiation elements disposed alternately in a second column intermediate to the first and third columns, wherein said step (a) includes forming the first field of at least one picture element comprised of the first, second, third and fourth radiation elements disposed in the first and second columns and rows of the display apparatus, said step (b) includes the forming of the second field of a second, different picture element comprised of the first, second, third and fourth radiation elements disposed in the first and second columns of the second and third rows of the display device, and thereafter forming a third field comprised of at least one third picture element comprising the first, second, third and fourth radiation elements disposed in the second and third columns of the first and second rows, and thereafter forming a fourth field comprised of at least one fourth picture element comprising first, second, third and fourth radiation elements disposed in the second and third rows and columns of the display apparatus.

13. The method as claimed in claim 10, wherein the display apparatus includes third and fourth radiation elements for emitting, respectively, radiation of a second wavelength of first and second low intensity levels, the first and second radiation elements emitting respectively, radiation of a first wavelength of the first and second intensity levels, wherein said step (a) includes the forming of picture elements comprised of the first, second, third and fourth radiation elements with at least one idle row and column formed therebetween; said step (b) includes the forming the second field of picture elements of the first, second, third and fourth radiation elements selected from a row of the first picture element and the adjacent idle row; and further including the steps of energizing the radiation elements to form a third field wherein a third picture element is formed of the first, second, third and fourth radiation elements selected from a column of the first picture element and the adjacent idle column; and energizing the radiation elements selectively to form a fourth field of fourth picture elements comprised of selected first, second, third and fourth radiation elements selected in part from the idle row and column associated with the first picture element.

14. A color picture display system comprising:

a matrix type display apparatus having arrays of picture elements, each array composed of a plurality of luminous elements of different colors and brightness levels; and

means for selectively controlling the energization of each of said plurality of luminous elements of each picture element to "on" and "off" states in accordance with color and luminance signals applied to the picture element, the "on" luminous elements, in combination, providing a display of color picture information of the picture element and the picture elements, in combination, providing a display of a color picture of one frame.

15. A color picture display system according to claim 14, in which said matrix type display apparatus is a plasma display panel having first and second sets of electrodes disposed in intersecting relationship and defining discharge cells at the said intersections of said electrodes said discharge cells serving as said luminous elements, each picture element being composed of nine discharge cells defined by the intersections of three adjacent electrodes of each of said first and second sets, and

said energizing means comprises means for applying different electric signals to said electrodes of said first set of each picture element to cause the discharge cells associated with a given electrode of said first set to discharge at a frequency different from said cells associated with the other electrodes of said first set, thereby to cause the three discharge cells associated with each electrode of said first set to emit respectively different colors.

16. A color picture display system according to claim 15, wherein said first and second sets of electrodes are disposed in inclined relationship with respect to each other.
Description



BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a system for driving a display apparatus having luminous elements arranged in a matrix form, and more particularly to a scanning system for such an apparatus which provides for enhanced resolution in an image display.

2. Description of the Prior Art

An existing display apparatus of the type having luminous elements arranged in a matrix form is such, for example, as a plasma display panel in which first and second sets of electrodes are arranged to cross each other in adjacent but spaced relation to each other, whereby discharge cells formed at the intersecting points of the electrodes serve as luminous elements. In such a plasma display panel, in order to obtain a display with half tones, picture elements are each formed with a plurality of discharge cells and the brightnesses of the discharge cells making up each picture element are selected different from each other. For exammple, in the case of forming one picture element with four discharge cells, if their brightness levels are selected to be 1, 2, 4 and 8, a display with 16 tone gradations can be achieved. The arrangement of these discharge cells is such, for example, as depicted in FIG. 1, in which discharge cells having a brightness level of 1 are formed at the intersecting points of electrodes Y11, Y21, . . . Ym1 with those X11, X21, . . . Xn1; discharge cells having a brightness level of 2 are formed at the intersecting points of electrodes Y12, Y22, . . . Ym2 with those X11, X21, . . . Xn1; and discharge cells having brightness levels of 4 and 8 are formed in a similar manner. An alternating sustain voltage is always impressed to the electrodes X and Y, and a write or erase voltage is impressed to selected ones of the electrodes to display a character, a figure or the like. The brightness levels of the discharge cells can be set at 1, 2, 4 and 8 or other desired values as by providing, in front of the discharge cells, filters of different transmission factors, selecting the numbers of discharging of the cells within a unit time to be different from one another or coating phosphor on the cells and making the coated areas or their luminous efficiency to be different from one another.

Writing of a display content can be achieved by scanning the electrodes in a manner similar to that of scanning in television and, in this case, the interlace system can be employed. Namely, interlaced scanning of lines of picture elements is effected: for example, lines of the picture elements A'-1, A'-2, . . . are scanned in a first field and those B'-1, B'-2, . . . are scanned in a second field as indicated at the left-hand side of FIG. 1. With the arrangement of FIG. 1, however, the number of the electrodes Y necessary for displaying a TV picture by such scanning is 1,024 to provide 512 scanning lines.

SUMMARY OF THE INVENTION

This invention is to provide a novel driving system for matrix type display apparatus in which a gradation display or a color gradation display is achieved and combinations of luminous elements making up individual picture elements are sequentially changed at every field to provide a display with high resolution.

The driving system for matrix type display apparatus in which picture elements are each formed with a plurality of luminous elements of different brightness levels and/or colors emitted therefrom and are arranged in a matrix form, is characterized in that one frame constituting one picture is formed with a plurality of fields; and some of the luminous elements of adjacent picture elements are selectively combined into individual picture elements at every field.

Other objects, features and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram, for the comparison of one example of a conventional driving system for a plasma display panel having picture elements each formed with four discharge cells and one example of this invention system for such a plasma display panel;

FIG. 2 is a circuit diagram of the principal part of one example of this invention;

FIGS. 3A and B, 4, 5A and 5B, inclusive, are diagrams for explaining the operation of other examples of this invention;

FIG. 6 is a diagram, for explaining the discharge cell arrangement for a color gradation display;

FIG. 7 shows a series of impression voltage waveforms in case of a gradation display by changing the numbers of discharging of discharge cells within a unit time; FIG. 8 is a diagram, for explaining erasing and writing operations;

FIG. 9 is a block diagram showing another example of this invention as being applied to a TV picture display;

FIG. 10 is a diagram, for explaining the electrode arrangement in another example of this invention; and

FIG. 11 is a diagram, for explaining electrode connections.

DESCRIPTION OF PREFERRED EMBODIMENTS

With reference to FIG. 1, one example of this invention for a gradation display will be described. With the interlace system in which one frame consists of two fields, in the first field, electrodes are sequentially scanned in pairs without leaving any space for the second field, as indicated by A-1, A-2, . . . at the right-hand side of FIG. 1; and, in the second field, adjacent ones of the electrodes scanned in the first field are sequentially scanned in pairs as indicated by B-1, B-2. Accordingly, in the first field, write scanning of the picture elements surrounded by dash-dot-dash lines is effected and, in the second field, write scanning of the picture elements surrounded by dotted lines is achieved. If the number of horizontal scanning lines is 512, the number of the electrodes necessary for such scanning system is 513, which is about one-half of that required in the conventional system.

FIG. 2 illustrates the principal part of a circuit for performing such scanning as described above. A horizontal synchronizing signal HS is applied to an 8-bit counter 1 and its counted content is decoded by a decoder 2. A video signal having its brightness level converted into a 4-bit signal is applied to a shift register 3 which stores therein those signals of one horizontal line period. In FIG. 2, only the shift register 3 for one picture element is illustrated. A vertical synchronizing signal is applied to a flip-flop circuit (not shown) to provide field signals F1 and F2 corresponding to the first and second fields respectively. The field signals F1 and F2 are supplied to an AND gate group G1 together with the output from the decoder 2 and the AND gate group G1 is further supplied with timing pulses t1 and t2. Reference characters G2 and G4 designate OR gate groups, DV.sub.x and DV.sub.y drivers, G3 an AND gate group, and Q1 and Q2 transistors, which supply a sustain voltage Vs to the electrodes through a diode matrix.

For example, in the first field, the field signal F1 is applied to the AND gate group G1 and when an output 1 of the decoder 2 designating a first scanning line has become 1 and the timing pulse t1 has also become 1, a voltage is impressed to the electrode Y11 from the driver DV.sub.y. At this time, where the contents of the shift register 3 is 1, 4 and 8, upon application of the timing pulse t1 to the AND gate group G1 simultaneously with the application of a write timing pulse tw to the AND gate group G3, a voltage is impressed to the electrodes X11 and X12 from the drivers DV.sub.x to effect writing in the discharge cells at brightness levels of 1 and 4. Then, when the timing pulse t2 is applied, a voltage is impressed to the electrode Y12 and if the contents of the shift register 3 are such as mentioned above, a voltage is impressed to the electrode X12 to effect writing in the discharge cells at the brightness level of 8. Thus, each picture element is at a brightness level of 11.

Next, when an output (2) of the decoder 2 designating a second scanning field has become 1, voltages are impressed to the electrodes Y21 and Y22 in accordance with the timing pulses t1 and t2 in the same manner as described above. At that time, since the shift register 3 has stored therein the 4-bit video signal for the next horizontal scanning line period, writing is achieved in accordance with the stored contents.

In the second field, the field signal F2 is applied to the AND gate group G1, so that once the output (1) of the decoder 2 has become 1, a voltage is impressed to the electrode Y21 upon application of the timing pulse t1 and to the electrode Y12 upon application of the timing pulse t2. Where the output (2) of the decoder 2 is 1, a voltage is supplied to the electrode Y31 (not shown) upon application of the timing pulse t1 and to the electrode Y22 upon application of the timing pulse t2.

Consequently, in the first field, pairs of electrodes Ym1 and Ym2 (m = 1, 2, 3, . . . ) are sequentially scanned as indicated by A-1, A-2, . . . and, in the second field, pairs of electrodes Ym2 and Y(m + 1) are sequentially scanned as indicated by B-1, B-2, . . . . In the case of writing by such scanning, it is a matter of course to erase a previous state by inserting an erasing pulse before scanning. When the scanning is stopped, the image at that time is displayed in a stationary condition. Namely, the plasma display panel has a memory function, so that if the scanning is stopped when a required image is being displayed, the image can be continuously displayed in a stationary condition without providing any external buffer memory.

In the foregoing example, the picture elements are each formed with four discharge cells and interlaced scanning of the horizontal electrodes is carried out, but interlaced scanning of the vertical electrodes is also possible. Namely, dot interlaced scanning is effected and FIG. 3 is a diagram for explaining it. FIG. 3A shows picture elements in the case where one frame consists of four fields, and FIG. 3B shows the order of scanning of the picture elements on the transmitting side, numerals in brackets indicating picture element numbers. A video signal for transmission is produced by scanning picture elements of such numbers whose tenth and unit digits are both odd, that is, (11), (13), (15), . . . (31), (33), . . . , in the first field, those of such numbers whose tenth and unit digits are even and odd respectively in the second field, those of such numbers whose tenth and unit digits are odd and even respectively in the third field, and those of such numbers whose tenth and unit digits are both even in the fourth field.

Upon reception of such a video signal transmitted, in the first and second fields, the picture elements are scanned without leaving any interlaced one as in the foregoing example. Namely, in the first field, the picture elements (11), (13), (15), . . . (31), (33), (35), . . . are scanned as shown in the first field in FIG. 3A and, in the second field, the picture elements (21), (23), (25), . . . (41), (43), (45), . . . are scanned as depicted in the second field in FIG. 3A. In the next third and fourth fields, picture elements are each composed of two pairs of horizontally adjoining discharge cells of the picture elements in the first and second fields, i.e. in the third field, picture elements (12), (16), . . . (32), (34), (36), . . . are scanned and, in the fourth field, those (22), (24), (26), . . . (42), (44), (46), . . . are scanned. Thus, one frame is completed.

In the case where the scannning procedures on the transmitting side cannot be altered as depicted in FIG. 3B, that is, for example, in an existing television transmission, it is possible to achieve such scanning as described above by selecting the timing for reading out the content of the shift register on the receiving side. With such dot interlaced scanning, it is possible to further enhance resolution even with less electrodes.

FIG. 4 is a diagram for explaining an embodiment of this invention applied to a color gradation display. This is the case where each picture element is composed of red, blue and green discharge cell R, B, and G having brightness levels 1, 2 and 4 respectively. Reference characters R1, R2, R4, B1, B2, B4, G1, G2 and G4 designate red, blue and green discharge cells having the brightness levels corresponding to their respective numerals. In such a plasma display panel, scanning by the conventional sequential scanning system requires 1,536 horizontal electrodes for 512 scanning lines but, in the case of one frame consisting of three fields in accordance with the present invention, the number of electrodes required can be reduced down to the same as that of scanning lines forming one frame. Namely, in the first field, triads of horizontal electrodes are sequentially scanned; in the second field, triads of horizontal electrodes excepting the uppermost one are sequentially scanned; and, in the third field, triads of horizontal electrodes excepting the two upper ones are sequentially scanned, as clearly shown in FIG. 4. In this manner, scanning for one frame is achieved.

By the application of such divisional scanning to the vertical electrodes, too, one frame is composed of nine fields, which enables enhancement of resolution with a small number of electrodes.

In FIGS. 5A and 5B, there is illustrated a modification of the above-described one-frame-with-nine-fields scanning system, in which one frame consists of four fields. FIG. 5A shows that, in the first and second fields, the electrodes are scanned in such a form that one electrode corresponding to picture elements surrounded by blocks 101 and 102 is inserted as an idle electrode between adjacent picture elements surrounded by blocks 100 and 200. FIG. 5B shows that, in the third and fourth fields, the electrodes are scanned in such form that one electrode is inserted as an idle electrode between adjacent picture elements surrounded by blocks 300 and 400 in the same manner as described above. In this example, the number of the electrodes is two-thirds of that used in the conventional sequential scanning system and the brightness equivalent centers of gravity of the respective picture elements are arranged at regular intervals.

The driving method for the color gray scale display will hereinbelow be described more in detail with reference to FIG. 6 and others subsequent thereto. FIG. 6 illustrates the construction of picture elements of a plasma display panel which employs matrix electrodes in combination with the dot arrangement of FIG. 4. In FIG. 6, reference characters XA1, XB1, XC1, XA2, . . . and YA1, YB1, YC1 YA2, . . . designate electrodes; R1, R2 and R4 red discharge cells having a brightness ratio of, for example, 1:2:4; and B1, B2, B4, G1, G2 G4 blue and green discharge cells also having a similar brightness ratio. Each broken-line block represents one picture element. The colors can be obtained by coating color emissive phosphors or providing filters, and the brightness ratio can be obtained by selecting the numbers of times of radiation of the cells within a unit time different from one another or providing filters of different transmission factors. The brightnesses can also be made different from one another by other means, for example, making the areas, thicknesses or luminous efficiencies of the phosphors coated different from one another. In the case of selecting the numbers of times of radiation different from one another, as depicted in FIG. 7, by applying voltages VA, VB, VC and VY to the electrodes XA1, XA2, . . . , XB1, XB2, . . . , XC1 XC2, . . . and YA1, YB1, YC1, YA2 respectively, the discharge cells R1, B1 and G1 radiate once within a unit time T, the discharge cells G2, R2 and B2 radiate twice and the discharge cells B4, G4 and R4 radiate four times, thus providing the brightness ratio of 1:2:4. Accordingly, if one picture element is made up of these nine discharge cells, a color display of eight gradations can be provided by selective combinations of the discharge cells. Each discharge cell serves as one dot of one picture element. If the kinds of colors of the dots is taken as n and if the number of gradations is taken as m, one picture element is formed with an assembly of (m + n)'s dots. If the brightness ratio is selected to be, for example, 1:2:4:8 . . . , the content of one picture element is the combination of 2.sup.mn kinds. Usually, three kinds of colors: red R, Green G and blue B, are the most effective and if the number of dots of the same color is three, eight gradations can be obtained as described above.

In TV pictures or the like, the number of gradations m is reguired to be about 5 or 6, in which case, it is sufficient only to increase the number of dots making up one picture element. However, only an increase in the number of dots lowers resolution, so that it is necessary to reduce the pitch of the discharge cells, that is, the pitch of the electrodes.

FIG. 8 is a diagram, for explaining a write operation in the plasma display panel of the construction shown in FIG. 6. In FIG. 8, reference character VXA, VXB and VXC identify voltages for the impression to the electrodes XA1, XA2, . . . , XB1, XB2, . . . and XC1, XC2, . . . respectively; VYA, VYB and VYC voltages for the impression to the electrodes YA1, YA2, . . . YB1, YB2, . . . and YC1, YC2, . . . respectively; PE an erasing pulse; and PW a write pulse. The erasing pulse PE is simultaneously applied to all of the discharge cells of one picture element to effect erasing at one time, but selective erasing of each discharge cell or every three discharge cell is also possible. However, this results in prolongation of the erasing time. Then, by simultaneous impression of the write pulse PW to the electrodes YA1 and XA1, the discharge cell R1 is selected. Further, the impression of the write pulse PW to the electrodes YB1 and XB1 leads to the selection of the discharge cell R2. Next, the impression of the write pulse PW to the electrodes YC1, XB1 and XC1 results in the selection of the electrodes B2 and R4. As a result of this, the discharge cells R1, R2, R4 and B2 of the picture element radiate in blue-red (purple) light. The above writing method is a parallel one, but it is also possible to effect writing in each discharge cell. Further, by coating a dielectric layer on the electrodes to provide a memory function as in the plasma display panel, the discharge radiation by the cells is continued until the next selective erasing is achieved.

FIG. 9 is a block diagram showing another example of this invention as being applied to a color television. The output from an intermediate-frequency amplifier 10 is detected by a detector circuit 11, a Y signal derived therefrom is amplified by an amplifier 12 and applied to a matrix circuit 17. A signal amplified by a carrier chrominance signal band amplifier 13 is demodulated by a demodulator circuit 15 into I and Q signals. In this case, a burst signal is separated and amplified by a burst separator-amplifier 14 to control a subcarrier phase control oscillator 16, the output from which is applied to the demodulator circuit 15 to achieve the demodulating operation. The matrix circuit 17 reproduces red G, green G and blue B signals from the Y, I and Q signals fed thereto, and the red, green and blue signals R, G and B are applied to decoders 18A, 18B and 18C respectively to provide decoded outputs of the brightness levels 1, 2 and 4 for each color. A shift register 19A is supplied with the outputs (1), (2) and (4) derived from the decoders 18A, 18B and 18C respectively; a shift register 19B is supplied with the outputs (2), (4) and (1) from the decoders 18A, 18B and 18C respectively; and a shift register 19C is supplied with the outputs (4), (1) and (2) from the decoders 18A, 18B and 18C respectively, thus storing a signal corresponding to one scanning line. During the horizontal blanking period, the contents of the shift registers 19A, 19B and 19C are transferred to hold registers 20A, 20B and 20C respectively. In accordance with the content of the hold register 20A, writing is effected by a gate signal g.sub.1 in the electrodes XA1, XB1, XC1, XA2, . . . and, in this case, a write pulse is impressed by the gate signal g.sub.1 to the electrode YA1. Since one scanning line corresponds to a triad of the electrodes YA1, YB1 and YC1, information one-third that of one scanning line is written in parallel. Then, gate signals g.sub.2 and g.sub.3 are sequentially applied to achieve writing as described above and writing for one scanning line is completed by effecting the writing operation three times. Erasing is carried out before such writing and since the shift registers 19A, 19B and 19C are inoperative during the horizontal blanking period, it is also possible to dispense with the hold registers. For storing information of one scanning line, the capacity of each shift register becomes inevitably large but the capacity of the shift register can be reduced by dividing one scanning line into a plurality of segments and writing the information of each segment immediately after it is stored in the shift register, that is, by writing the information a plurality of times for one scanning line. Further, various systems can be considered for the interlaced scanning and color television can be realized.

In the example of FIG. 6, dots of higher brightness are arranged in a vertical direction, so that streaks sometimes become noticeable in the vertical direction. This can be avoided by disposing the vertical electrodes XA1, XB1, XC1, XA2, . . . inclined at 45.degree. to the horizontal ones YA1, YB1, YC1, YA2, . . . , as depicted in FIG. 10. In this case, since the electrodes except one on the diagonal are divided into two groups, they are interconnected as shown in FIG. 11 and these connections may be formed on the panel simultaneously with the formation of the electrodes or may be formed at projecting portions of the electrodes from the panel.

In the present example, the electrode lead-out position is shifted one by one at every three writing operations for red, green and blue colors, so that the content of each register is shifted to the right at every writing.

As described above, in this example, a gradation color display can easily be achieved, so that characters, figures, TV pictures and so on can be displayed. Further an image display with high resolution can be achieved by making up one frame with a plurality of fields and altering the combinations of discharge cells of adjacent picture elements at every scanning of each field, as described previously.

Although this invention has been described in connection with the case where discharge cells are employed as luminous elements, the invention is applicable to the case where luminous elements such as luminescent diodes or the like are arranged in a matrix form. Further, by transmitting the brightness levels as PCM signals in the form of picture element signal arrangement from the transmitting side for interlaced or dot interlaced scanning, an image display on the display apparatus can be achieved with much ease and a gradation display with high resolution can be produced by the use of a small number of electrodes. In the case of conventional transmission signals, the scanning system of each of the foregoing examples can be practised by selecting the timing for reading out memories on the receiving side.

With the present invention, as described in the foregoing, in the case of achieving a gradation display and a color gradation display by the employment of the scanning system, one frame is formed with a plurality of fields and some of luminous elements of adjacent picture elements are selectively combined together and scanned as one picture element for each field, so that the number of electrodes used can be reduced. Therefore, the display apparatus can be made small in size and the picture element pitch can also be reduced, and hence resolution can be enhanced.

This invention is not limited specifically to the foregoing examples but may be variously modified and varied within the scope of the concepts defined in the appended claims.

* * * * *


uspto.report is an independent third-party trademark research tool that is not affiliated, endorsed, or sponsored by the United States Patent and Trademark Office (USPTO) or any other governmental organization. The information provided by uspto.report is based on publicly available data at the time of writing and is intended for informational purposes only.

While we strive to provide accurate and up-to-date information, we do not guarantee the accuracy, completeness, reliability, or suitability of the information displayed on this site. The use of this site is at your own risk. Any reliance you place on such information is therefore strictly at your own risk.

All official trademark data, including owner information, should be verified by visiting the official USPTO website at www.uspto.gov. This site is not intended to replace professional legal advice and should not be used as a substitute for consulting with a legal professional who is knowledgeable about trademark law.

© 2024 USPTO.report | Privacy Policy | Resources | RSS Feed of Trademarks | Trademark Filings Twitter Feed