1. Technical Field
The present invention relates to an electro-optical device including an organic EL (electro luminescent) element, a liquid crystal a method for driving thereof, and electronic apparatus.
2. Related Art
In the past, an electro-optical device including organic EL elements as an electric optical element has been provided. The electro-optical device is provided with various drive circuits for supplying a predetermined current or voltage to the organic EL elements or the like. Such a drive circuit, for example, often includes capacitative elements connected in parallel with the organic EL elements. In this case, a data potential is supplied to the anode of the organic EL element and one electrode of the capacitative element, and a reference potential is supplied to the cathode of the organic EL element and the other electrode of the capacitative element. With this configuration, a current based on accumulated electric charges in the capacitative element, that is, data potential, can be performed to the organic EL element, so that stable drive or the like of the organic EL element can be performed.
As such an electro-optical device, a device disclosed in JP-A-2000-122608, for example, is known.
Meanwhile, the following problems exist in the above-described electro-optical device. Specifically, to make a light emission amount (a time integral value of light emission brightness) of the organic EL element become a sufficient value, a charge amount accumulated in the capacitative element needs to be increased. Therefore, it is necessary to make the capacitance of the capacitative element become a very large value. However, because a physical area allowed for each drive circuit is limited, it is difficult ever to realize such a large capacitance value.
Accordingly, in order to solve the problem, a technique is disclosed in U.S. Patent Application Publication No. 2009/0195534. In the technique, capacitative elements, each included in respective drive circuit (unit circuit), are used for driving one organic EL element. In a simple example, in the case where drive circuits are arranged in one line and the number of the circuits is N (therefore, the number of the capacitative elements and the number of the organic EL elements are both N), in driving one organic EL element, firstly, charging in response to data potential corresponding to the organic EL element is performed simultaneously to N-pieces of capacitative elements included in all drive circuits, and secondly, simultaneous discharging (more specifically, current supply) of the N-pieces of capacitative elements is performed to the organic EL element.
With this configuration, the above-mentioned inconvenience becomes negligible.
However, there is still a room for improvement in such a technique. Specifically, according to the above-mentioned example, simultaneous charging and simultaneous discharging to all of N-pieces of capacitative elements are performed to drive one organic EL element, and at each point of charging and discharging, an extremely large current may be generated instantaneously. Such a problem could be more serious as the number of capacitative elements or the number of drive circuits becomes larger. Therefore, if such large current may be generated, a problem occurs that noise associated with the current is generated, and as a result, properly controlled operation for all drive circuits becomes difficult, or adverse effect or the like to peripheral equipment due to the noise radiation will be concerned.
An advantage of some aspects of the invention is to provide an electro-optical device, a driving method thereof and electronic apparatus capable of solving at least a part of the above-described problems.
Further, another advantage of some aspects of the invention is to provide an electro-optical device, a driving method thereof and electronic apparatus capable of solving problems related to the electro-optical device, the driving method thereof or the electronic apparatus in the above aspects.
The electro-optical device according to a first aspect of the invention, to solve the above-described problems, is equipped with a plurality of unit circuits arranged corresponding to crossings between a plurality of scanning lines and a plurality of data lines, a plurality of wirings that constitutes each of the plurality of scanning lines, a scanning line drive circuit that sequentially selects one of the scanning lines while sequentially selecting one of the wirings included in the scanning line, at every driving period within each unit circuit, and a data line drive circuit that, at every period within the each unit period which is a writing period before the drive period is started, outputs a data potential in response to the gradation data of the unit circuit, which corresponds to the wiring selected in the driving period within the unit period, to a data line corresponding to the unit circuit out of the each data line, in which each of the plurality of unit circuits includes an electric optical element that displays gradation in response to the data potential, a capacitative element having a first electrode connected to a capacitance line and a second electrode connected to the data line, and a switching element that is disposed between the second electrode and the electric optical element and, by being electrically conducted in selecting one of the wirings by the scanning line drive circuit, allows the second electrode and the electric optical element to be electrically conducted.
According to an aspect of the invention, the following operation can be realized, for example.
Specifically, firstly, in writing period, charging to the capacitative element in the unit circuit as described above, which is connected to a predetermined data line is performed. Herein, a capacitative element being a subject to be charged is limited to an element included in “the unit circuit corresponding to the wiring selected in a driving period”. Secondly, in a driving period after the writing period, discharging of the capacitative element that became the subject to be charged first is performed to an electric optical element included in a unit circuit corresponding to one selected wiring.
In such an operation, the number of unit circuits involved in charging to the capacitative element and discharging from it becomes smaller compared to the number of all unit circuits. In short, according to an aspect of the invention, during a period when the above-mentioned first and second operations are performed once, capacitative elements in all unit circuits are not necessarily involved in such charging and discharging.
As described above, according to an aspect of the invention, the number of capacitative elements that become the subject of charging or discharging becomes smaller at least compared to the total number of capacitative elements, so that a risk that an extremely large current is instantaneously generated is really reduced. Therefore, according to an aspect of the invention, generation of noise can be suppressed, and generation of various inconvenience associated with the noise can be suppressed.
Meanwhile, according to an aspect of the invention, “the scanning line drive circuit” “sequentially selects one scanning line while sequentially selecting one wiring included in the scanning line” has the following meaning. That is to say, assuming that numbers 1, 2, 3, . . . are applied to scanning lines, α-1, α-2, . . . , α-β (herein, α is the number of the above-mentioned scanning line, β is an integer of 2 or more) are applied to β-pieces of wirings included in each of the scanning lines, the “sequentially selecting” means selecting each wiring in the order of 1-1, 1-2, . . . , 1-β, 2-1, 2-2, . . . , 2-β, 3-1, 3-2, . . . , 3-β, . . . .
Further, the electro-optical device according to a second aspect of the invention, to solve the above-described problems, is equipped with a plurality of unit circuits arranged corresponding to crossings between a plurality of scanning lines and a plurality of data lines; a plurality of wirings that constitutes each of the plurality of scanning lines; a scanning line drive circuit that sequentially selects one of the scanning lines while sequentially selecting one of the wirings included in the scanning line, at every driving period within each unit circuit; a data line drive circuit that, at every period within the each unit period which is a writing period before the drive period is started, outputs a data potential in response to the gradation data of the unit circuit, which corresponds to the wiring selected in the driving period within the unit period, to a data line corresponding to the unit circuit out of the each data line; and a plurality of first switching elements disposed between each of the plurality of data lines and the data line drive circuit, in which each of the plurality of unit circuits includes: an electric optical element that displays gradation in response to the data potential; and a second switching element that is disposed between the data line and the electric optical element and, by being electrically conducted in selecting one of the wirings by the scanning line drive circuit, allows the data line and the electric optical element to be electrically conducted, and when the data line drive circuit outputs the data potential to the data line, the first switching element corresponding to the data line enters an electrically conducting state in the writing period, to electrically conduct the data line with the data line drive circuit, by which charge in response to the data potential is accumulated in the capacitance attached to data line, and enters a non-conducting state in the driving period, to prevent the data line from being electrically conducted with the data line drive circuit.
According to an aspect of the invention, operational effect similar to the operational effect exerted by the above-described electro-optical device according to the first aspect of the invention is exerted.
However, according to an aspect of the invention, the subject to be charged is the “capacitance attached to the data line”, and therefore, the subject to be discharged is also the “capacitance”. Meanwhile, the discharging, based on the above-described provision, is realized by making the data line and data line drive circuit enter a non-conducting state in the driving period while the data line and the electric optical element enter an electrically conducting state.
Herein, the “capacitance attached to the data line” includes a parasitic capacitance in the data line itself (furthermore specifically, a parasitic capacitance or the like between the data line and one electrode that constitutes the electric optical element), for example. Further, the “capacitance attached to data line” also includes the “capacitative element” that constitutes the electro-optical device according to the first aspect of the invention mentioned above (therefore, in this regard, it can be concluded that the electro-optical device according to the second aspect has a wider capture range than the electro-optical device according to the first aspect).
As described above, according to an aspect of the invention, in addition to the operational effect exerted by the electro-optical device according to the first aspect, installation of the above-mentioned “capacitative element” is not an imperative factor, so that cost reduction required for installing the capacitative element can be achieved. Further, due to the same reason, size reduction of the unit circuit can be realized, higher definition is also made possible.
Meanwhile, meaning of “selection of scanning line” is the same as the above-described one.
The electro-optical device according to the first or second aspects of the invention may be constituted that the unit period for one unit circuit corresponding to one wiring included in the scanning line of one circuit out of the plurality of unit circuits overlaps at least a part of the unit period for another unit circuit corresponding to another wiring included in the scanning line.
According to this aspect, because unit time for one unit circuit partially overlaps unit time for another unit circuit, in a predetermined given time, it becomes possible to efficiently drive electric optical elements in all unit circuits.
Meanwhile, in this aspect, the “unit period according to unit circuit” means such period in a case where the output of the data potential and the selection of the scanning line which are performed in the above-mentioned writing period and driving period are executed for the unit circuit such that the electric optical element in the unit circuit reaches predetermined gradation.
Further, the electro-optical device according to the first or second aspects of the invention, the data line drive circuit may be constituted so as to include a switching section that determines to which data line out of the data lines the data potential should be supplied.
According to this aspect, since the data line drive circuit includes the switching section, to supply of data potential to each data line or the like is preferably performed, and as a result, the effect according to the invention mentioned above can be enjoyed more effectively.
Further, regarding this aspect, more specifically, if one scanning line includes “two” wirings, for example, two data lines that correspond to two unit circuits corresponding to each of the two wirings could be a data line to be switched by the switching section. Then, by this arrangement, during a writing period for one unit circuit out of the two, a data potential is supplied to one data line corresponding to it, and during a writing period for the other unit circuit, a data potential is supplied to the other data line corresponding to it. In this case, since the one data line is open in a way particularly during the latter writing period, the period can be applied to charge discharging from the capacitance attached to data line, more specifically, to a driving period for the one unit circuit. This means that, at least a part of “the driving period” and “the writing period” for each of the both unit circuits can be overlapped.
Consequently, according to this aspect, the effect according to the invention mentioned above is exerted more effectively.
Further, the electro-optical device according to the first or second aspect of the invention may be constituted that the data line drive circuit includes a plurality of data potential generating sections that generates the data potential corresponding to each of the plurality of data lines independently to each other.
According to this aspect, since the data line drive circuit includes an independent constitution that is a plurality of data potential generating sections corresponding to each data line, output of a data potential for one data line and output of a data potential for another data line can be performed in parallel, for example. This means that at least a part of “the writing period” for both unit circuits corresponding to the both data lines can be overlapped.
Meanwhile, in this aspect as well, overlapping at least a part of “the driving period” and “the writing period” for each of the both unit circuits, as described in a preceding aspect, can be similarly realized.
Consequently, according to this aspect, the effect according to the invention mentioned above is exerted more effectively.
Further, in the electro-optical device according to the first or second aspect of the invention, it further includes an auxiliary capacitative element whose one electrode is connected to the data line other than the capacitative element in the each unit circuit or capacitance attached to the data line, may be constituted.
According to this aspect, even in a case where total capacitance of each capacitative element connected to a data line corresponding to the unit circuit or capacitance attached to the data line is small, comparing to capacitance necessary to make a light emission amount of an electric optical element in a selected unit circuit corresponding to a wiring included in the scanning line, shortage can be compensated by the capacitance of an auxiliary capacitative element.
Further, in the electro-optical device according to the first or second aspect of the invention may be constituted that a unit circuit corresponding to one wiring out of the plurality of wirings included in one of the scanning lines and a unit circuit that is adjacent to the unit circuit along the extending direction of the scanning line and corresponds to another wiring out of the plurality of wirings constitute one unit circuit group, and the unit circuit group is repeatedly arrayed along the extending direction of the scanning line,
According to this aspect, as a simple example, on the premise that the scanning line includes two wirings of the first and second wirings, when attention is paid to one scanning line, repetitive array along with the line that a unit circuit corresponding to a first wiring, a unit circuit corresponding to a second wiring, a unit circuit corresponding to the first wiring, and so on is performed.
In such a case, since unit circuits being the subject of writing and driving are distributed for the array of all unit circuits with good balance, image display or the like can be performed more preferably.
Meanwhile, it goes without saying that this aspect is not limited to a case where the scanning line includes two wirings as in the same manner of the invention in general.
Further, electronic apparatus of the invention, to solve the problems, is equipped with the above-described various electro-optical devices.
Since the electronic apparatus of the invention is equipped with the above-described various electro-optical devices, generation of large current is avoided in simultaneous charging to capacitative element or capacitance attached to the wiring or simultaneous discharging from it, and as a result, it becomes possible to display a higher-quality image.
On the other hand, the driving method of an electro-optical device according to the first aspect of the invention, to solve the problems, is a driving method of an electro-optical device that includes an electric optical element, which is equipped with a plurality of wirings that constitute a scanning line and a plurality of unit circuits corresponding to each of the wirings, and reaches predetermined gradation by charge discharging from a capacitative element in the unit circuit, in which the method includes: a first process for supplying a first data potential only to a data line that corresponds to the unit circuit corresponding to one wiring out of the each wiring to accumulate charge in response to the first data potential in the capacitative element connected to the data line; a second process for making a switching element between the capacitative element and the electric optical element in the unit circuit corresponding to the one wiring enter an electrically conducting state by selecting the one wiring; a third process for supplying the second data potential only to a data line corresponding to the unit circuit that corresponds to another wiring out of the each wiring to accumulate charge in response to the second data potential in the capacitative element connected to the data line; and a fourth process for making a switching element between the capacitative element and the electric optical element in the unit circuit corresponding to the another wiring enter an electrically conducting state by selecting the another wiring.
According to an aspect of the invention, in the first and second processes, the capacitative element involved in charging to capacitative element and discharging from it is limited to an element connected to “a data line corresponding to the unit circuit that corresponds to one wiring”. In short, since the invention is on the premise that a capacitative element included in “a unit circuit corresponding to another wiring” exists, all capacitative elements are not involved in such charging and discharging. The same applies to the third and fourth processes related to “another wiring”.
As described above, according to an aspect of the invention, since the number of capacitative elements being a subject of charging or discharging becomes smaller than at least the total number of capacitative elements, a risk that extremely large current is instantaneously generated is really reduced. Therefore, according to an aspect of the invention, noise generation can be suppressed, and generation of various inconveniences associated with it can be suppressed.
Further, as it is obvious from according to an aspect of the invention, it becomes possible to preferably drive an electro-optical device according to the above-described invention.
Note that, in the invention, there may be a plurality of capacitative elements in the case where “capacitative element connected to data line”.
Further, the driving method of an electro-optical device according to the second aspect of the invention, to solve the above-described problems, is a driving method of an electro-optical device equipped with a plurality of wirings that constitute scanning lines and a plurality of unit circuits corresponding to each of the wirings, and including an electric optical element that reaches predetermined gradation by charge discharging from capacitance attached to a data line extending so as to cross the scanning line, in which the method includes: a first process for supplying a first data potential only to the data line corresponding to the unit circuit corresponding to one wiring out of the each wiring to accumulate charge in response to the first data potential in the capacitance attached to the data line; a second process for making a switching element between the electric optical element and the data line in the unit circuit corresponding to the one wiring enter an electrically conducting state by selecting the one wiring; a third process for supplying a second data potential only to a data line corresponding to the unit circuit that corresponds to another wiring out of the each wiring to accumulate charge in response to the second data potential in the capacitance attached to the data line; and a fourth process for making a switching element between the electric optical element and the data line in the unit circuit corresponding to the another wiring enter an electrically conducting state by selecting the another wiring.
According to an aspect of the invention, operational effect similar to the operational effect exerted by the driving method of an electro-optical device according to the first aspect of the above-described invention is exerted. Note that, meaning of “capacitance attached to data line” mentioned in the invention is the same as the above-described one.
The driving method of an electro-optical device according to the first or second aspects of the invention may be constituted that the first process is performed in parallel with at least one process of the third and fourth processes, or the third process is performed in parallel with at least one process of the first and second processes.
According to this aspect, for example, implementation of the first process and the fourth process partially overlaps with each other, it becomes possible to efficiently drive electric optical elements in all unit circuits in a predetermined given time.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
In the following, a first embodiment according to an aspect of the invention will be explained referring to
In
As shown in
Of the constitutions above, m-pieces of the scanning lines 3 severally include one set of two wirings 3_O and 3_E as shown in
The scanning line drive circuit 200 shown in
The data line drive circuit 300 shown in
In this case, because each scanning line 3 includes two wirings 3_O and 3_E as mentioned above, each of the data potentials VD[1] to VD[n] is also supplied in response to selection or non-selection of the two wirings 3_O or 3_E. Specifically, for example, in response to selection of the wiring 3_O that constitutes the scanning line 3 on the first row, data potentials VD[1], VD[3], . . . , VD[2k−1], . . . (k is an appropriate integer, but 2k−1≦n) for unit circuits P1 that are positioned on odd-numbered columns are output to each data line 6. In response to selection of the wiring 3_E, data potentials VD[2], VD[4], . . . , VD[2k], . . . for unit circuits P1 that are positioned on even-numbered columns are output to each data line 6, and so on (refer to
The data line drive circuit 300, to realize the above described, as shown in
Of these parts, the data potential generating sections 301 are provided such that one section supports every two data lines 6. Each of the data potential generating sections 301 generates a data potential in response to on which column in the pixel array section 100 two data lines 6 corresponding to the section are positioned. For example, the data potential generating section 301 shown on the far left side in
Further, control signals SEL_O and SEL_E are output to the wiring for SW 303_O and 303_E respectively. The control signals SEL_O and SEL_E transit between the active state and non-active state similarly while appropriately synchronizing with transition of the scan signals G[1]_O to G[m]_E between each active state and non-active state.
Each of the first and second switching transistors 302_O and 302_E is an N-channel type, and enters the electrically conducting state when the control signals SEL_O and SEL_E enter the active state. Then, in response to the transition of each transistor (302_O, 302_E) between the electrically conducting and non-conducting states, a data potential VD[j−1] is output to the data line 6 of the (j−1)th column in some cases, and a data potential VD[j] is output to the data line 6 of the (j)th column in other cases.
Each unit circuit P1, as shown in
The electric optical element 8 is an OLED (Organic Light Emitting Diode) element where a light-emitting layer of an organic EL material is interposed between an anode and a cathode, as shown in
The capacitative element C1 is an element for holding the data potential VD[j] supplied from the data line 6. As shown in
Meanwhile, the capacitance line 30 to which a fixed potential is supplied is commonly connected to each unit circuit P1. Further, grounding potential is supplied to a constant potential line. For example, a negative potential is supplied to the constant potential line, and data potential VD[n] showing the highest brightness, out of the data potential VD[j], may be a positive potential and the data potential VD[1] showing the lowest brightness, out of the data potential VD[j], may be a negative potential. More specifically, grounding potential may exist between the data potential VD[n] and the data potential VD[1]. With this arrangement, amplitude of the data potential VD[j] to the grounding potential can be reduced, and lower power consumption can be achieved.
The transistor Tr is an N-channel type, and is a switching element that electrically conducts a second electrode E2 of the capacitative element C1 with the electric optical element 8 by being electrically conducted in selecting a scanning line 3. As shown in
Then, the gate of the transistor Tr is connected to the scanning line 3. Herein, in the case where the gate of the transistor Tr is connected to the scanning line 3, the first embodiment has the following characteristics. Specifically, as shown in
Thus, as the scan signal G[i]_O transits to the active state, transistors Tr that belong to the odd-numbered column enter an On state, and the second electrode E2 and the electric optical element 8 are electrically conducted. On the other hand, as the scan signal G[i]_O transits to a non-active state, transistors Tr enter an Off state, and the second electrode E2 and the electric optical element 8 enter a non-conducting state. The same applies to the scan signal G[i]_E.
Next, the operation and action of the electro-optical device 10 according to the first embodiment will be explained referring to each drawing of
The electro-optical device 10 has basic operations i and ii below.
i. Writing Operation
This writing operation is an operation to allow a capacitative element C1 in a unit circuit P1 that belongs to a column including an electric optical element 8, which is included in each unit circuit P1 corresponding to a wiring 3_O or 3_E, to hold the data potential VD[j] corresponding to the light emission gradation of the electric optical element 8. For example, the data potential VD[3] of a electro-optical device 8 that corresponds to the wiring 3_E included in the scanning line 3 of the second row and positioned on the third column (refer to
ii. Light-Emitting Operation (Driving of Electric Optical Element)
This light-emitting operation is an operation to allow the electric optical element 8 to perform light emission based on the data potential VD[j] held by the capacitative elements C1 in i. This operation includes supplying an active scan signal G[i]_O or G[i]_E to the wiring 3_O or corresponding to the unit circuit P1 including the electric optical element 8 and making the transistor Tr in the unit circuit P1 enter the electrically conducting state. Thus, the electric optical element 8 is supplied with a current in response to charge accumulated in the capacitative elements C1, and emits light.
The electro-optical device 10 of the first embodiment is basically operated based on an appropriate combination of the above-described i and ii, and more details on these points are as follows.
Firstly, in a writing period Pw shown on the far left side in
As described above, the i. writing operation for the electric optical element 8 in each unit circuit P1 that is positioned on the first row and the odd-numbered column is ended. Therefore, in this writing period Pw, only half the capacitative element C1 of all the capacitative elements C1 in the pixel array section 100 are involved in charging, and a plurality of the capacitative elements C1 that severally belong to each of the first column, third column, . . . , (2k−1)th column, . . . accumulate charge in response to the data potentials VD[1], VD[3], . . . , VD[2k−1], . . . .
Subsequently, in a driving period Pd adjacent to the writing period Pw, the scanning line drive circuit 200 supplies an active-state scan signal G[1]_O to the wiring 3_O included in the scanning line 3 on the first row. Thus, the electric optical element 8 corresponding to the wiring 3_O simultaneously emits light (the ii. light-emitting operation). In this case, a current that flows in the electric optical element 8 corresponds to a charge amount accumulated in the above-mentioned plurality of the capacitative elements C1. The above ends one unit period 1T (refer to top areas of
Further, in the first embodiment, i. writing operation for the electric optical element 8 in each unit circuit P1 positioned on the first row and the even-numbered column is performed in parallel with this. Although the essence of an operation in this case is not different from the case of the above-mentioned writing operation, contrary to the above-described case, the control signal SEL_O becomes non-active and the control signal SEL_E becomes active, the first switching transistor 302_O enters the Off state and the second switching transistor 302_E enters the On state. Further, data potential generating section 301 creates potential VD[2], VD[4], . . . , VD[2k], . . . , and supplies it to each data line 6 positioned on a corresponding even-numbered column (in
In
On the other hand, in
After this, the above-described operation is performed repeatedly. Specifically, at any given point, a writing operation for the capacitative element C1 that belongs to an odd-numbered column and a light-emitting operation of the electric optical element 8 that belongs to an even-numbered column are performed. At another point, the electric optical element 8 being a subject of light emission will shift sequentially downward while the opposite operation is performed in
Meanwhile, a period IV shown in
The electro-optical device 10 of the first embodiment, which has such a constitution and performs operation, gives the following effect.
Specifically, according to the electro-optical device 10 of the first embodiment, each scanning line 3 includes two wirings 3_O and 3_E, and each of the wiring 3_O and 3_E is connected to unit circuits P1 positioned on the odd-numbered column and even-numbered column, so that the number of the capacitative elements C1 involved in simultaneous charging or simultaneous discharging in order to drive one electric optical element 8 is half the all capacitative elements C1, and a risk that extremely large current is instantaneously generated is extremely reduced even in each point of charging and discharging.
This is grasped more clearly by comparison between the first embodiment and
In
With such a constitution in
Then, in
As it is obvious from the comparison above, according to the first embodiment, fear that the large current is generated extremely low. Therefore, in the first embodiment, various risks such as the one that noise associated with the current is generated, a risk that properly controlled operation regarding all unit circuits P1 becomes difficult due to the noise, or fear that adverse effect or the like to peripheral apparatus due to radiation of the noise is extremely reduced.
Second Embodiment
In the following, the second embodiment according to an aspect of the invention will be explained referring to
In the second embodiment, firstly, as shown in
Further, in the second embodiment, the gate of the transistor Tr included in each unit circuit P1 is connected as follows. Firstly, the gate of the transistor Tr, which is included in a unit circuit P1 positioned on the first column, fourth column, . . . , (1+3z)th column, . . . , is connected to the wiring 3_F that constitutes the scanning line 3. Secondly, the gate of the transistor Tr, which is included in a unit circuit P1 positioned on the second column, fifth column, . . . , (2+3z)th column, . . . , is connected to the wiring 3_S that constitutes the scanning line 3. Thirdly, the gate of the transistor Tr, which is included in a unit circuit P1 positioned on the third column, sixth column, . . . , (3+3z)th column, . . . is connected to the wiring 3_T that constitutes the scanning line 3 (in the above, z=0, 1, 2, . . . . However, z satisfies 3+3z≦m). Meanwhile, in the following, the three types of unit circuits P1 above may be referred to as a unit circuit P1 of a first group, a unit circuit P1 of a second group, and a unit circuit P1 of a third group.
On the other hand, in the second embodiment, as shown in
Note that, the data potential generating section 304 falls under one specific example of the “data potential generating section” in the invention. Further, this Specification uses the reference numeral “304” as a reference numeral that collectively calls the reference numerals “304_F”, “304_S” and “304_T”.
The electro-optical device according to the second embodiment equipped with such a constitution operates or acts as follows. Firstly, in the writing period Pw shown on the far left side of
Subsequently, in the second embodiment, in the writing period Pw, the writing operation for the electric optical element 8 in a unit circuit P1 positioned on the first row and a unit circuit P1 of the second group is also performed in parallel. Specifically, as shown in
The reason why such an operation is possible is that the data potential generating sections 304_F and 304_S are provided individually for each data line 6.
Consequently, the data potential VD[1] corresponding to the electric optical element 8 of the first row and first column, for example, is held by the capacitative elements C1 in all unit circuits P1 included in the first column. On the other hand, the data potential VD[2] corresponding to the electric optical element 8 of the first row and second column is held by the capacitative elements C1 in all unit circuits P1 included in the second column.
Subsequently, in a driving period Pd adjacent to the above-mentioned writing period Pw for the unit circuit P1 of the first row and first group, the scanning line drive circuit 200 supplies an active-state scan signal G[1]_F to the wiring 3_F included in the scanning line 3 on the first row. Thus, electric optical elements 8 that belong to the unit circuit P1 positioned on the first row and the unit circuit P1 of the first group emit light simultaneously (ii. light-emitting operation). In this case, a current flowing in the electric optical elements 8 corresponds to a charge amount accumulated in the capacitative elements C1 that belong to the above-mentioned first column. Consequently, one unit period 1T ends (refer to top areas of
Meanwhile, in this case, the above-mentioned writing period Pw for the first row and second groups still continues. In short, the light-emitting operation for the first group and the writing operation for the second group are performed in parallel.
After this, although there is a difference in wirings or data potential generating sections to be involved such as the wiring 3_F, 3_S and 3_T and the data potential generating sections 304_F, 304_S and 304_T, the same operation as the one described above will be performed repeatedly (refer to
It is evident that an operational effect that is not substantially different from the operational effect exerted by the first embodiment is exerted by the above-described second embodiment.
Moreover, according to the second embodiment, since the data potential generating section 304 for each data line is equipped, the writing operation for the capacitative elements C1 that belong to the unit circuits P1 of the first and second, the second and third, or the first and third groups can be performed in parallel as described the above. Specifically, comparing this operation with the fact that the writing operation for an odd-numbered column and a light-emitting operation for an even-numbered column (or its opposite) can be performed in parallel in the first embodiment, time usage is more efficient in the second embodiment. Actually in
As described, according to the second embodiment, an operational effect better than the operational effect exerted by the first embodiment could be exerted.
Further, in the second embodiment, as comparison between
The embodiments according to the invention have been explained above, the electro-optical device and pixel circuit according to the invention are not limited to the above-described embodiments, but various modifications can be made.
1. In the first and second embodiments, a subject to be charged in i. writing operation mentioned above is the capacitative element C1 included in the unit circuit P1, but the invention is not limited to such.
For example, as shown in
In such, in the writing period Pw in each unit period 1T shown in
According to such, even if a total capacitance value of the capacitative elements C1 connected to a data line 6 corresponding to one electric optical elements 8 is insufficient to make a light emission amount of the electric optical element 8 be a sufficient value, the shortage can be compensated by using a capacitance of the auxiliary capacitative element Cs.
2. In the first and second embodiment, where the capacitative element C1 is included in the unit circuit P1 is explained, but the invention is not limited to such.
For example, as shown in
According to such, cost reduction required for installing the above-mentioned capacitative element C1 can be achieved. Further, due to the same reason, size reduction of the unit circuit P11 can be also realized, so that higher definition is made possible.
Meanwhile, an aspect where the auxiliary capacitative element Cs, which was explained referring to
3 . In the second embodiment, an aspect where one scanning line 3 includes the three wiring 3_F, 3_S and 3_T, and the data potential generating section 304 corresponding to each data line 6 is equipped is explained, these two matters are independent to each other. In short, if the first embodiment is used as a reference, an aspect where the data potential generating section 304 corresponding to each data line 6 is merely added instead of a data potential generating section 301 or the like that constitutes the aspect is naturally within the scope of the invention. Further, an aspect where additional three or more of wirings are merely added to each scanning line 3 of the first embodiment is within the scope of the invention.
4. In each embodiment, one each of the data line 6 is provided for each column of unit circuit P1, the invention is not limited to such an aspect. For example, in each embodiment, as one scanning line 3 has a plurality of wirings, the data line 6 may also have a plurality of wirings. Then, in this case, for example, an aspect where a unit circuit P1 positioned on an odd-numbered row is connected to one wiring out of the plurality of wirings and a unit circuit P1 positioned on an even-numbered row is connected to another wiring is possible as a variation of a specific mode of the invention. With this variation, in one opportunity, a capacitative element C1 being a subject of charging or discharging is a capacitative element C1 that belongs to a unit circuit P1 of the first group and is included in a unit circuit P1 positioned on an odd-numbered row, for example, the above-mentioned effect of preventing the generation of a large current may be achieved better.
Application
Next, electronic apparatus to which the electro-optical device 10 according to the embodiment is applied will be explained.
As electronic apparatus to which the electro-optical device according to an aspect of the invention is applied, other than the ones shown in
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