TWI426489B - Image display device and method of controlling a display device - Google Patents

Description

Active matrix image display device and control method thereof

The present invention relates to a display device, a display control circuit, and an image display method.

In particular, the present invention relates to an active matrix image display device comprising: - a plurality of illuminators, forming an array of illuminators distributed in a row and a straight line, each illuminator being periodically addressable with a display signal value, the value representing Display data during image; a current modulator connected in series with each illuminator of the array to form an illuminator/modulator in series, the modulator including a source, a drain, and a gate, the modulator being capable of being The drain current is crossed to supply power to the illuminator because the voltage between one of the drain and the source and the gate is greater than or equal to the trip threshold voltage of the modulator; - a charge storage capacitor, in the image During the period, the control voltage can be maintained at the gate of each modulator; the selection mechanism can select the illuminator of the same course; and the driving mechanism of the illuminator illumination, in each straight line, including the power supply mechanism of the illuminators, The output includes one of the series connected ends of the illuminators/modulators, and at least one motion amplifier for controlling the corresponding modulator, having an inverting input (-), a non-inverting input (+), and Output Modulation coupled thereto while selecting the light emitting device is changed, the output of the amplifier can be connected to this gate of each modulator of the straight pole, so that the pole control voltage applied to the gate.

Video display devices are increasingly used in various applications such as motor vehicles, digital cameras, or mobile phones.

In the known display device, the illuminator is formed according to an organic light-emitting crystal lattice, such as an OLED (Organic Light Emitting Diode) type display device.

In particular, passive matrix OLED displays have been widely used in the market. However, it consumes too much power and has a short life.

Active matrix OLED display devices include integrated electronic components that exhibit many advantages, such as low power consumption, high resolution, compatibility with video rates, and longevity over passive matrix OLED display devices.

Conventionally, such display devices include an active matrix, in particular formed by an array of illuminators. Each illuminator is attached to an element or sub-picture of the image to be displayed, and is addressed by an array of straight-line electrodes and row electrodes via an addressing circuit.

The addressing circuit specifically includes a current modulator capable of driving current through the illuminator, thereby driving the luminosity of each primitive or sub-picture of the display device.

In the active matrix, these modulators are thin film transistor TFTs, which are made of polycrystalline germanium based on an amorphous germanium layer according to low temperature polysilicon (LTPS) technology. However, this technique introduces a local spatial variation in the trip voltage between these transistors. These changes are due to the fact that the combination and dimension (size) of the ruthenium grains cannot be sufficiently controlled in the step of crystallizing amorphous yttrium (Si-a) into poly-Si.

Therefore, a TFT transistor that is powered by the same supply voltage and controlled by a uniform display current or voltage, generates a current of a different intensity. In addition, the trip voltage of the thin film transistor is easily changed in an uneven manner after a lapse of time.

Nowadays, the intensity of the luminescence emitted by the illuminator is directly proportional to the current passing through, and the difference in the jump threshold of these transistors causes uneven brightness of the display device including the transistors. As a result, the photometric levels are different, revealing the user's visual discomfort.

To limit this discomfort, various circuits have been proposed to compensate for the jump threshold voltage.

For example, European Patent No. EP-1 340 019 describes a display device comprising a compensation circuit comprising an operational amplifier having an input coupled to the gate of the modulator and a non-inverting input coupled to the same illuminator. The anode does not involve a modulator associated with the illuminator.

However, this device is extremely complicated, and it is particularly necessary to control a large number of switches.

It is an object of the invention to achieve a relatively simple display device.

To this end, the present invention is directed to an active matrix image display device, characterized in that one of the non-inverting input and the inverting input of the operational amplifier is connected to the output of the power supply mechanism, and thus the gate of the modulator, When connected to the output of the operational amplifier, one of the illuminators is selected to form a feedback loop of the operational amplifier.

Therefore, contrary to the primitive circuit described in the above EP 1340019, the input of the operational amplifier is not connected to the common terminal of the illuminator/modulator series of each primitive, but is one of the ends of the series.

Therefore, the present invention can directly command current, and supply power to the illuminators in each of the straight rows, at least during the addressing of the illuminators, to supply power to the illuminators. An advantage of the present invention is that this current is not required to be measured by executing this command.

Each illuminator is periodically addressed, for each image to be displayed, or for each image, depending on the display method used.

According to a particular embodiment, the device includes one or more of the following characteristics.

One of the ends of each of the illuminator/modulator series connected to the output of the power supply mechanism corresponds to the drain or source of the modulator.

The output of the operational amplifier 35, that is, the transmission control signal Vc, the display signal V _{d a t a 2 2} , V _{d a t a 2 3} , and the jump of the modulator 26 coupled to the selected illuminators 22, 23, 24 It depends on the voltage limit V _{t h} . The control signal Vc can be charged to the capacitor 30.

The operational amplifier is coupled to one of the non-inverting input (+) and the inverting input (-) of the output and is capable of receiving a signal, depending on the value of the displayed signal, the value of which is intended to be addressed to the illuminator selected from the straight line.

According to a first major variant, the power supply mechanism further comprises a drive generator adapted to provide a drive signal to one of the ends of the illuminator/modulator series corresponding to the illuminator, feeding the power in a discontinuous manner to each straight line The illuminator, the drive signal is dependent on the display signal value, the value of which is intended to be addressed to the illuminator selected from the straight line. Therefore, the drive generator supplies power to the illuminators one by one only during its addressing.

The power supply mechanism generally includes a continuous generator, and its function is to supply power to the straight-line illuminators outside the addressing stage. These devices require an exchange mechanism suitable for powering the illuminator between the drive generator and the continuation generator. In practice, there are generally two additional switches in each addressing circuit, one for the illuminator/modulator of the circuit to be connected to the address generator in the addressing phase, and the other for the illuminator/modulator in series outside the addressing phase. Connect to the continuous generator.

As previously mentioned, the output of the driver generator is connected to one of the non-inverting input (+) and inverting input (-) of the operational amplifier. This same output is also connected to the end of the corresponding illuminator/modulator in series via the switch that is closed for addressing during the illuminator addressing of the straight line.

The drive generator includes a display voltage generator and a series of resistive elements, and the voltage generator is adapted to generate a voltage, depending on the value of the display signal, the value intended to be addressed to the illuminator selected from the straight line.

This resistor is a resistor inside the voltage generator.

Due to this series resistor, the value of the current flowing in the illuminator during this resistor and during addressing is irrelevant to the trip voltage of the modulator associated with the illuminator. The current value is proportional to the difference between the display signal value and the voltage value applied to the other of the non-inverting input and the inverting input of the operational amplifier, and is inversely proportional to the resistance value of the resistive element.

According to a second preferred main variant, the power supply mechanism comprises a drive generator capable of continuously supplying the same drive signal to one of the illuminator/modulator terminals of the straight line, and continuously supplying power to the entire set of straight-line illuminators, The drive signal is determined by the previous address and the sum of the display signal values of the entire set of illuminators that are currently addressed during the image. This has the advantage that it is not necessary to have an additional continuous generator as in the first major variant described above.

The drive generator includes a display voltage generator and a series of resistive elements, and the voltage generator is adapted to generate a voltage, depending on the sum of the previous address and the display signal value to be addressed to the straight set of illuminators during the image period. .

This resistor can be a resistor inside the voltage generator. Due to this series resistor, the value of the current flowing in this resistor and thus in the illuminator, i.e., the trip threshold voltage of the modulator associated with this illuminator. The current value is proportional to the display signal value and the voltage value applied to one of the non-inverting input and the inverting input of the operational amplifier, and is inversely proportional to the resistance value of the resistive element.

The switching mechanism is not included between the output of the power supply mechanism and the series of illuminators/regulators in series. The addressing circuit of the illuminator is preferably simplified compared to the first major variant, since there is no need to alternate between the different drive generators at the end of the illuminator/modulator series in series, as in the first major variant.

The output of the driver generator is connected to one of the non-inverting input (+) and the inverting input (-) of the operational amplifier on the one hand, and does not need to be exchanged in the other, and is connected in series with the corresponding transmitter/modulator. end.

The voltage generator is coupled to the resistive element to deliver a drive current according to the following equation: Where R is a resistive element; V _{r e f n} is a reference voltage associated with illuminator n; V _{d a d a n} is the display voltage value addressed to illuminator n; P is the total number of in-line illuminators.

The drive mechanism further includes a reference generator capable of transmitting a reference signal to the other of the operational amplifier inverting input (-) and the non-inverting input (+).

Each illuminator exhibits particular electrical and/or optical properties, and each reference signal value depends on the electrical and/or optical performance.

Each illuminator is associated with color illumination, and the reference signal can be modulated as a function of the color assigned to the selected illuminator.

The specified white tones are marked with three color coordinates. Thanks to the invention, the color effect of the device is easily optimized, and the aging difference between the illuminators can be compensated.

The illuminator comprises a plurality of adjacent emitters adapted to emit different colors, and for each complex number, the reference signal is deployed to the plurality of illuminators in such a manner that the illuminators are addressed by the same display signal value. , using the complex number to emit the white hue.

The drive mechanism further includes a data storage mechanism capable of storing the image period during the display signal value of each illuminator for storage.

The object of the present invention is also a method of an active matrix image display device, the display device comprising a plurality of illuminators forming an array of illuminators distributed in a horizontal row and a straight line, each illuminator being capable of being periodically addressed by using a display signal value, the value representing Display data during the image; a current modulator comprising a source, a drain, a gate, one of the drain and the source of each modulator, in series with the illuminator of the array to form an illuminator comprising both ends / modulator in series; a selection mechanism capable of selecting a row of emitters; a charge storage capacitor capable of maintaining a control voltage at the gate or modulators during the image; a drive mechanism for direct illuminator illumination, including at least An operational amplifier having an inverting input, a non-inverting input, and an output; the method comprising the steps of: - transmitting a selection signal (V _{s e l e c t} ) to the horizontal illuminator by using a selection mechanism; The driving signal (I) is one of the series ends of the illuminators/modulators in the straight line; and - the driving signal (Vc) is applied to the gates of the modulators of the selected illuminators by using the driving mechanism The pole is further characterized by the following steps: - selecting a row illuminator, a gate coupled to the modulator of the operational amplifier output, and an op amp non-inverting input coupled to the output of the illuminator supply mechanism And one of the inverting inputs forms a feedback loop of the operational amplifier.

According to a particular embodiment, the method includes the feature that the drive signal is due to a total of display signal values addressed to the straight-line full set of illuminators during the image period.

The invention will be more apparent from the following description of the embodiments.

Fig. 1 shows an image display device of the present invention comprising an active matrix 1 using a control mechanism 2.

In a known manner, the active matrix 1 comprises complex addressing circuits 3, 4, 5, 6, each associated with an illuminator (not shown), arranged in rows and straight rows.

The control mechanism 2 of the active matrix includes a control system 7, a selection control circuit 8, and an address control circuit 10.

The control system 7 is capable of receiving image display signals, processing (e.g., decoding and decomposing), and transmitting synchronization signals to the selection control circuit 8, and display signals to the address control circuit 10.

The selection control circuit 8 is coupled to the plurality of course electrodes 14, 15, each associated with a row of illuminators. When receiving the synchronization signal, the circuit 8 is adapted to successively generate the selected pulse wave V _{s e l e c t} at each of the row electrodes 14, first selecting the entire group of addressing circuits of the course by the scanning frequency corresponding to the image period. 3, 6. Select pulse wave V _{s e l e c t to} select the logic data for the illuminator.

The address control circuit 10 is coupled to a plurality of straight-line electrodes 16, 17 and a plurality of drive electrodes 18, 19, each associated with a straight-line illuminator 21A, 21B. A plurality of addressable drive units 20A, 20B, each of the straight-line electrodes 16, 17 and the drive electrodes 18, 19 are addressed and addressed to the addressing circuits 3, 4, 5, 6 of the straight-line illuminators 21A, 21B.

The row electrodes 14, 15, the straight electrodes 16, 17 and the drive electrodes 18, 19 can be individually selected, addressed and powered to a particular addressing circuit in the circuit set 3, 4, 5, 6 of the display device.

Therefore, by selecting the row electrode 14 of the display device, actuating the driving unit 20A, and transmitting the control voltage Vc to the electrode 16, and driving the current I to the electrode of the straight line 21A, the electrode in the course and the straight-line illuminator can be activated. The electrodes 16, 18 of 21A cross the circuit 3, and none of the other circuits 4...5 that are also straight ahead are activated.

Figure 2 shows illuminators 22, 23, 24, each associated with a set of primitives 3, 4, 5 for a row of illuminators 21A, and an address driven unit 20A for the illuminator 21A, and addressing Circuits 3, 4, 5, 6 are used to select control circuit 8.

The illuminators 22, 23, and 24 of the display device are organic light emitting diodes. Includes anode and cathode. The structure of these diodes is "conventional", meaning that the anode is the lower layer on the side of the substrate and the cathode is on the upper layer.

The intensity of the light emitted by these illuminators is directly proportional to the current passing through it. Each illuminator constitutes a basic primitive. These basic elements are in the same color (same color), and in color, they are red, green and blue.

Within the architecture of the present invention, the straight illuminator groups 22, 23, 24 are associated with sub-primitives of the same color. Three adjacent straight illuminators are associated with red, green, and blue. Having the illuminators 22, 23, 24 over the same bias voltage as the function of the current/voltage characteristics of the illuminator as a function of the current/voltage characteristics of the illuminators, in particular the associated sub-pictures of the respective illuminators 22, 23, 24 Color is a function.

Since the addressing circuits 3, 4, 5 of the active matrix 1 are identical, only the circuit 3 will be described in detail.

This circuit 3 includes a circuit modulator 26, a switch 28 formed of a transistor, a storage capacitor 29 and a supply electrode 30.

The current modulator 26 and the switch 28 are thin film transistors according to the technique of depositing polycrystalline silicon (Poly-Si), amorphous germanium (a-Si) or single crystal germanium (μc-Si) on a glass substrate. . These components consist of three electrodes: a drain, a source through which a modulated current called a drain current is passed, and a gate to which a control voltage Vc is applied.

The source of the modulator 26 is coupled to the anode of the illuminator 22 in a manner such as coupled to the modulator 26 and the illuminator 22 in series. One end 31 of the series is here the drain of the modulator 26 and is coupled to the drive electrode 18. The gate of the modulator 26 is coupled on the one hand to the first terminal of the capacitor 29 and, in addition, to the energized electrode (drain or source) of the switch 28 via the electrical line 33. Another energized electrode (drain or source) of switch 28 is coupled to straight electrode 16. The gate of switch 28 is coupled to row electrode 14. The second terminal of each of the capacitors 29 of the circuit groups 3, 4, 5 of the straight line 21A is connected to the power supply electrode 30. Finally, the other end 32 of each modulator/illuminator in series, here the cathode of the illuminator 22, is coupled to the supply electrode 34. The two power supply electrodes 30, 34 can be connected to the same potential together using conductors (not shown).

The modulator 26 shown in Fig. 2 is of the n-type, so that during operation, its drain current flows between its drain and source. It should be noted that such devices can also be used to drive p-type TFTs, still having diodes of conventional construction, as shown in FIG.

The capacitor 29 disposed between the gate and the source of the modulator 26 is adapted to substantially maintain a certain control pressure at the gate of the modulator 26, which is equivalent to the image period T1, T2, so as to maintain the illumination during this period. The brightness of the device.

The supply electrode 30 can be at the necessary voltage to bias to the desired potential of one of the capacitor terminals, as described in the prior art.

The driving unit 20A is adapted to compensate for the tripping threshold voltage V _{t h of} each of the addressing circuits 3, 4, and 5 of the addressing circuit group 3, 4, 5 of the straight line 21A, and to supply the illuminators 22 for the illuminator 21A to go straight. , 23, 24.

For this purpose, an operational amplifier 35 is included having an inverting input (-), a non-inverting input (+), and an output. The output of this amplifier 35 is connected to the straight-line electrode 16, and its non-inverting input (+) is coupled to the drive electrode 18, ensuring that the straight-line illuminator is powered via the associated modulator. Thus, this non-inverting input (+) is simultaneously coupled to the anode of each of the illuminators 22, 23, 24 of the straight line 21A via the associated modulator 26.

Therefore, whenever the switch 28 of the addressing circuits 3, 4, 5 of the straight-line illuminator 21A is closed, the feedback loop of the amplifier 35 is driven by the drive electrode 18, the end 31 of the modulator/illuminator series, the modulator 26, Line 33, and straight electrode 16 are formed. It is to be noted that the end 31 of the series of modulators/illuminators forming the feedback loop, in the specific example shown in Figures 2 and 10, corresponds to one of the diodes or sources of the series modulator.

The amplifier 35 is capable of operating in feedback, thereby compensating for the tripping threshold voltage V _{t h} of each of the modulators 26 of the addressing circuits 3, 4, 5 of the linear illuminators 21A, as will be described later.

Further, the drive unit 20A can address and supply power to the illuminators 22, 23, 24 of the straight line 21A using the drive current I. This current I depends on the display voltages V _{d a t a 2 2} , V _{d a t a 2 3} , V _{d a t a 2 4} of the illuminators 22, 23, 24 addressed to the straight line 21A.

For this purpose, a drive current generator 36 and a reference voltage generator 38 are coupled to the non-inverting input (+) and the inverting input (-) of the amplifier, respectively.

Current generator 36 is formed by a variable voltage generator 39 connected in series with resistor 40, and drive electrode 18 is coupled to the output of resistor 40 so that node 42 forms the output of current generator 36.

The generator 39 is a variable voltage generator whose voltage varies as a function of the display signal values V _{d a t a 2 2} , V _{d a t a 2 3} intended to be addressed to the illuminators 22, 23, as will be described later.

The generator 38 is a generator adapted to carry a reference voltage and is fixed at the time of setting of the display device, and is dedicated to straight travel. As a variant, a variable voltage generator can also be used; the change in the reference voltage is a function of the straight-line illuminator 21A addressed thereto.

The output of generator 38 can optionally be coupled via resistor 44 to the reflected input (-) of amplifier 35. This resistor 44 is not absolutely necessary for the operation of the drive unit 20A. Only the balance between the two inputs of the operational amplifier 35 has a beneficial function.

Capacitor 46 is also coupled between the inverting input (-) of amplifier 35, as needed, to the output of this amplifier. Resistor 44 and capacitor 46 form a compensation array that can advantageously improve accuracy and circuit stability.

Drive unit 20A also includes data storage mechanism 48, and control modules 50 of generators 38 and 39.

The storage mechanism 48 includes a database 52 adapted to store the display signal values V _{d a t a 2 2} , V _{d a t} of the illuminators 22, 23, 24 addressed to the straight line 21A during the previous image period T1. _{a 2 3} , another aspect stores the illuminators 22, 23 whose values are addressed to identify or locate the data.

These storage mechanisms 48 also include a directory 54 adapted to store reference voltage values that would be associated with the straight line 21A illuminator group. This value is determined by the red, green, and blue associated with the illuminators 22, 23 of the straight line 21A.

Illuminators associated with different colors show different current/voltage characteristics, as shown in Figure 12. Therefore, for the red illuminator terminal and the blue illuminator terminal, different voltages must be applied in order to obtain the same luminosity and the same current value through the illuminators.

The reference voltage values for each of the straight-line directories 54 are fixed here as a function of the illuminator color of the straight line 21A. This operation is performed in the factory at the time of setting the display device before use. These reference values are established to compensate for changes in current/voltage electrical characteristics and/or illuminating characteristics of various illuminators within the device, as detailed.

In general, since these characteristics mainly depend on the illuminating color of the illuminator, there are three different reference voltage values, the first value V _{r e f . R} is shared by the first straight red illuminator, and the second The value V _{r e f . G} is shared by the second straight green illuminator group, and the third value V _{r e f . B} is shared by the third straight blue illuminator group. According to more complex variations, these reference voltage values are dedicated to each straight line of the illuminator for compensating for changes in the current/voltage electrical characteristics and/or the luminosity characteristics of the straight illuminators (even with the same illuminating color).

Only when the display signal V _{d a t a} addressed to the illuminator is greater than the associated reference voltage V _{r e f} will the current flow through the illuminator. In order to avoid having to use the display signal of too high value, it is advisable to establish the reference voltage of the lowest possible value while the display device is set, and still obtain the required compensation.

The control module 50 is coupled to the storage mechanism 48 for searching and recording information within the organization.

In addition, module 50 is capable of receiving display signals transmitted by system 7 and controlling generators 38 and 39 as a function of the signals and information stored in storage mechanism 48.

In operation, circuits 8 and 10 are capable of successively addressing, powering, and selecting illuminator groups 22, 23, 24 of matrix 1.

In the on state, during the step 60 shown in FIG. 3, at the beginning of the first image frame T1, the driving unit 20A and the circuit 8 control the illumination of the first illuminator 22 of the straight line 21A. This step 60 includes steps 62 through 69.

During the step 62, the circuit 8 generates a selected pulse wave V _{s e l e c t 2 2} at the row electrode 14. This pulse wave can close the switch as shown in Fig. 4.

Parallel to the process in step 64, module 50 queries list 54 to determine the reference voltage associated with the straight line of illuminator 22. This reference voltage is particularly dependent on the color of the sub-picture associated with the straight illuminators 22, 23, 24.

In step 66, the module 50 controls the generator 38, so that the latter supplies the reference voltage V _{r e f 2 1 A} for the illuminator of the straight line 21A, the value of which is equal to and equal to V _{r e f a} .

Parallelly during the step 68, the module 50 receives from the control system 7 the value V _a of the display voltage V _{d a t a 2 2} to be addressed to the illuminator 22, and the identification or location of the addressed illuminator 22 associated with this value. . Module 50 then records this value V _a in database 52 and the identification of the illuminator to which this value is to be addressed.

At the same time, during the step 69, the module 50 controls the generator 39 so that the latter generates _a value V _a of the display voltage V _{d a t a 2 2} to be addressed to the illuminator 22.

Thus, generator 38 provides _a reference voltage _{Vr e f 2 1 A} equal to V _{r e f a} to the inverting input (-) of amplifier 35. At the same time, the generator 39 applies _a voltage V _{d a t a 2 2} equal to V _a to the resistor 40 as shown in FIG. This voltage V _a generates a drive current I=I _{2 2} via the drive electrode 18 and is directed to the drain of the modulator 26. The drive current I=I _{2 2 is} as shown in Fig. 7, and the following relationship is defined: Where V _a is the value of the display voltage V _{d a t a 2 2} generated by the generator 39, V _{r e f a} is the reference voltage value generated by the generator 38, and R is the value of the resistor 40. It is to be understood that the resistor 44 does not participate in the calculation of the current as needed, since no significant current flows through the resistor, at least compared to the drive current value of I _{2 2} .

The modulator 26, which takes into account the circuit 3 connected in series with the first illuminator 22, operates in its saturation mode (V _{g s} - V _{t h} <V _{d s} ), and the drain current through it is equal to the drive current I, maintaining the following relationship : Where I _{2 2} is the drain current through the modulator 26, V _{g s} is the voltage between the gate and the source of the modulator 26, k is a constant, depending on the inherent characteristics of the modulator 26, V _{t h} For the trip voltage of the modulator 26, V _{d s} is the voltage between the drain and the source of the modulator 26.

Due to the feedback loop of the present invention, the potential difference between the inverting input (-) and the non-inverting input (+) of the amplifier 35 disappears. The voltage at node 42 is then equal to V _{r e f a} . Therefore, the amplifier 35 automatically adjusts the control voltage Vc to the gate of the modulator 26 to a value such that the modulator 26 and the illuminator 22 connected in series are crossed by the current I = (V _a - V _{r e f a} ) / R Therefore, it is independent of the trip threshold voltage V _{t h of the} modulator 26. Thus, the illuminator 22 of the device can be directly compensated for tripping the threshold voltage without involving measuring the current through the illuminator.

The value V _{g s} is automatically derived from the control voltage value Vc.

The control voltage value Vc depends not only on the illuminator V _{d a t a 2 2} display signal, but also on the reference voltage V _{r e f a} associated with the illuminator, and because of the trip voltage V _{t h of the} modulator 26 And set.

Since the value V _{a of the} display voltage V _{d a t a 2 2} is given by the generator 39, the voltage V _{r e f a} is given by the generator 38, and the trip threshold voltage V _{t h} is an inherent characteristic of the configuration of the modulator 26, The control voltage Vc applied to the gate of the modulator 26 is adapted and modified by the amplifier 35 to compensate for the trip threshold voltage V _{t h of the} modulator.

Therefore, the control voltage Vc outputted from the amplifier 35, that is, the value V _{a of the} display voltage V _{d a t a 2 2} , is correctly adjusted to the voltage necessary for addressing the illuminator 22 without detaining the jump limit of the variator 26. What is the voltage V _{t h} value, even if the voltage changes with time.

For the remainder of the image period, capacitor 29 is used to maintain the control voltage Vc at the gate of modulator 26, while switch 28 of circuit 3 is turned back on, as is known in the art.

During the step 70, the second illuminator 23 of the straight line 21A is illuminated. Step 70 includes steps 72 through 79.

During the step 72, the circuit 8 delivers the selected pulse wave V _{s e l e c t 2 3} (as shown in Fig. 5) to the row electrode 15.

During the process of step 74, the module 50 determines the reference voltage V _{r e f 2 1 A} associated with the straight line of the illuminator 23 by querying the storage mechanism 48. Since the illuminator 23 and the illuminator 22 are in the same straight line, the illuminators are associated with the same color, the value of the reference voltage V _{r e f 2 1 A} V _{r e f a} , ie during the addressing of the first illuminator 22 The value V _{r e f a of the} reference voltage V _{r e f 2 2} occurring coincides.

During the step 76, the module 50 controls the reference generator 38 so that the latter occurs at the voltage V _{r e f a} determined during the step 74.

In the parallel process step 77, addressing module 50 to be addressed lighting system 7 receives the light emitter 23 is shown in a voltage value V _{d a t a 2 3} of V _b, as shown in FIG. 6, and from the value associated with this The identification and location of the device 23 is recorded in the database 52.

In the process step display 78, the module 50 is added to the same previously addressed straight light emitter 22 of the voltage V _{d a t a 2 2} The value V _a, and is intended addressed to a light emitting display 23 times the voltage V _{d a} The value of _{t a 2 3} is V _b .

Then, during a step 79, the module 50 controls the generator 39 to cause the latter to deliver a display voltage equal to the voltage value calculated in step 78.

Therefore, the new drive current becomes I=I _{2 3} +I _{2 2} , as shown in Fig. 9, flows through the resistor R and the drive electrode 18, which are connected in common to the non-inverting input (+) of the amplifier 35, The following relationship is defined:

The illuminator 22 illuminates the current I _{2 2} = (V _{d a t a 2 2} - V _{r e f a} ) / R necessary to continue to supply power to the modulator 26. In particular, the capacitor 29 is used instead of the amplifier 35, and the gate of the modulator 26 of the first circuit 3 maintains the same control voltage Vc because the switch 28 of the circuit 3 is now turned on. This voltage Vc commands the current intensity of the power supply illuminator 22 such that the intensity is equal to the programmed intensity during the step 60.

The residual current I _{2 3} =I-I _{2 2} =V _{d a t a 2 3} /R on the drive electrode 18 is supplied to the modulator 26 of the second circuit 4. Since the switch 28 of the circuit 4 has been closed during the step 72, the straight line electrode 16, the amplifier 35, the drive electrode 18, the end 31 of the modulator/illuminator series, the modulator 26 of the second circuit 4, and the second circuit Line 34 of 4 forms a new feedback loop for amplifier 35. Therefore, the control voltage Vc leaving the amplifier 35 compensates for the trip threshold voltage V _{t h} of the modulator 26 of the second circuit 4 as previously described.

The display device addressing method of the present invention continues to perform the same group of illuminators 22, 23, 24 of the straight line 21A during the same first image frame period of the period T1, and implements the addressing circuits 3, 4, 5 of the straight line 21A. The steps are similar to steps 72 to 79. In particular, the database 52 contains the display voltage p value V _{d a t a . n of} the illuminators addressed to the straight line 21A during the first image frame process, and the module 50 controls the generator 39 to cause the latter to deliver the display voltage. V= V _data.n . The drive current I through the drive electrode 18 is defined by the following general relationship: Wherein I is driven by the driving unit 20A and flows through the driving electrode 18; I _n is a current flowing through the illuminator n; V _{d a t a . n} is an image display voltage value addressed to the illuminator n ; V _{r e f 2 1 A} is the reference voltage value associated with the illuminator of the straight line 21A; p is the number of illuminators in the straight line 21A.

After the image period T1, the full set of illuminators 22, 23, 24 of the straight line 21A are illuminated as a function of the display voltage representing the image data to be displayed by the illuminators, and during the step 80, the circuit 3 is addressed for the second time. . This step 80 includes steps 82 through 89.

Steps 82, 84, 86, 87, 88, 89 are identical to steps 62, 64, 66, 68, 69, respectively, and will be described later. This second addressing of the circuit 3, the steps are modified such that the module 50: - received from the database 52 during the previous image frame, the display voltage V _{d a d a} previously addressed to the illuminator 22. The value of _{2 2} V _a , and receives from the system 7 _a new value V' _a of the display voltage V' _{d a t a 2 2} to be addressed to the illuminator 22, instead of the old value V _a , and recorded in the database 52; Total V _data.n minus the old value V _a , plus the new value V' _a .

The module 50 controls the generator 39 to cause the latter to deliver the display voltage, which is equal to the total The new value calculated by V _data.n.

The second addressing of circuit 4 is performed in the same manner. After the image period T2, the full set of illuminators 22, 23, 24 of the straight line 21A are illuminated as a function of the display voltage of the new image data to be displayed by the illuminators.

The other image frames follow the previous one, like the image frame T2, followed by the image frame T1.

In the specific example of the present invention, as shown in FIG. 6, it is equal to V._{r e f a} Reference voltage V_{r e f 2 2} The value has been applied to the inverting input (-) of amplifier 35, which is equal to V._a Display voltage V_{d a t a 2 2} The value has been addressed to the illuminator 22 during the image period T1. This voltage value V_a The addressing continues during the T2 process during the new image.

Therefore, total V _data.n is not modified during the second image period T2, and the charge stored by the capacitor 29 of the circuit 3 is not modified during the previous image period T1.

Similarly, in the second step of the illumination light emitter 23 (not shown on FIG. 3) which, addressed to show the voltage of the light emitting device 23, (FIG. 6) is equal to V _b during the first image and the previous period T3, However, it is zero during T4 during the next image period.

Therefore, total V _data-n simply reduces the V _{d a t a} value, so that the charge accumulated on the capacitor 29 of the circuit 4 is completely eliminated, and the latter exhibits a zero potential, which is characteristic of the unbright diode.

This has the advantage that the display device and display method can be seen, and the setup phase can be avoided before the programming of the addressing circuits 3, 4, 5 is planned.

It is beneficial to use one of the inputs applied to the amplifier 35 and to focus on the reference voltages of the illuminators in straight lines (or groups of straight lines, such as different color groups), thereby reducing the power consumption of the display device. In particular, if the reference voltage value is selected, not only can the electrical and/or photometric characteristics of the straight-line illuminators be compensated, but also the lowest possible average value of each straight-line reference voltage can be obtained, and the display signal value V _{d a t a} can be correspondingly Moving and lowering, thereby reducing the power generated by the power generator 39.

In the OLED display device having the conventional structure shown in Fig. 2, the anodes of the illuminators 22, 23 form an active matrix interface (a diode having a "conventional" structure): the 调 of the modulator 26 The pole (in the case of the n-type) or the source (in the p-type) is connected to the drive electrode 18, while the cathode of the illuminators 22, 23 is connected to the electrode 34. Drive electrode 18 is reconnected to node 42, one of the output of power supply 36, and the non-inverting input (+) of amplifier 35 converge there.

However, as shown in Fig. 11, the present invention is also applicable to a display device having a so-called inverted structure in which an illuminator cathode forms an interface for an active matrix: a drain of the modulator 26 (in terms of p type) The source or source (in the case of the n-type) is connected to the drive electrode 18, and the anode of the illuminators 22, 23 is connected to the electrode 34. Drive electrode 18 is coupled to node 42, and one of the outputs of power supply mechanism 36 is now concentrated with the inverting input (-) of amplifier 35. This circuit is more stable than described for the diode of the conventional structure, with the advantage that resistor 44 or any balancing and/or compensation capacitor 46 is not necessary today. The display signal is equivalent to a negative voltage, and the current of the diode is "pulled out" from the power supply electrode 34.

In a variant, the reference voltage is associated with the straight line of the illuminator. In this case, the storage mechanism 48 includes a database capable of storing reference voltage values to be applied to the straight rows of the illuminators. The drive unit 50 is adapted to pass through the database to look up the reference voltage value applied to the inverting input (-) of the amplifier 35 as a function of the identification or position of the illuminator.

In accordance with the present invention, it is desirable to establish a difference (V _{r e f x} - V _{r e f y} ) in the settings prior to use of the device in order to compensate for differences in the electrical and/or photometric characteristics of the straight rows of the illuminators.

1. . . Active matrix

2. . . Control mechanism

3,4,5,6. . . Addressing circuit

7. . . Control System

8. . . Selection control circuit

10. . . Address control circuit

14,15. . . Horizontal electrode

16,17. . . Straight electrode

18,19. . . Drive electrode

20A, 20B. . . Drive unit

21A, 21B. . . Straight line illuminator

22,23,24. . . Illuminator

26. . . Current modulator

28. . . switch

29. . . Capacitor

30,34. . . Power electrode

31. . . One end of the modulator/illuminator series

32. . . The other end of the modulator/illuminator series

33. . . Electrical circuit

35. . . Operational Amplifier

36. . . Drive current generator

38. . . Reference voltage generator

39. . . Variable voltage generator

40. . . Resistor

42. . . node

44. . . Resistor

46. . . Capacitor

48. . . Data storage organization

50. . . Control module

52. . . database

54. . . Directory

I. . . Drive current

Vc. . . Control voltage

V _{s e l e c t} . . . Pulse wave selection

T1, T2, T3, T4. . . Image period

V _{t h} . . . Jump off threshold voltage

V _{d a t a 2 2} , V _{d a t a 2 3} , V _{d a t a 2 4} . . . Display voltage

V _{r e f} . . . Reference voltage

V _{d a t a} . . . Display signal

V _a , V _b . . . Display voltage value

1 is a schematic view of a display device of the present invention; FIG. 2 is a partial schematic view of a display device shown in FIG. 1; FIG. 3 is a schematic view showing some steps of a control method of the present invention; A time-characteristic graph of the selection voltage of the first addressing circuit selection electrode of the display device; FIG. 5 is a time-morphological graph of the selection voltage of the selection electrode of the second addressing circuit of the display device of the present invention; FIG. 6 is a display of the present invention The addressing circuit of the same straight line device, especially the first and second circuits, the time-formed graph of the display voltage generated by the drive generator for the subsequent addressing; FIG. 7 is the 流 of the modulator flowing through the first addressing circuit. FIG. 8 is a graph showing the time history of the drain current flowing through the second address circuit modulator of the display device of the present invention; FIG. 9 is a graph showing the time shape of the driving current generated by the driving unit of the display device of the present invention. Figure 10 is a schematic diagram showing a first variation of the portion of the display device shown in Figure 2; and Figure 11 is a schematic diagram showing a second variation of the portion of the display device shown in Figure 2; Figure 12 All the current flowing through the light emitting device of the present invention is displayed to the voltage applied thereto is connected to the end of the graph of a function.

3,4,5. . . Addressing circuit

7. . . Control System

8. . . Selection control circuit

14,15. . . Horizontal electrode

16. . . Straight electrode

18. . . Drive electrode

20A. . . Drive unit

21A. . . Straight line illuminator

22,23,24. . . Illuminator

26. . . Current modulator

28. . . switch

29. . . Capacitor

30,34. . . Power electrode

31. . . One end of the modulator/illuminator series

32. . . The other end of the modulator/illuminator series

33. . . Electrical circuit

35. . . Operational Amplifier

36. . . Drive current generator

38. . . Reference voltage generator

39. . . Variable voltage generator

40. . . Resistor

42. . . node

44. . . Resistor

46. . . Capacitor

48. . . Data storage organization

50. . . Control module

52. . . database

54. . . Directory

I. . . Drive current

Vc. . . Control voltage

Claims (13)

An active matrix image display device comprising: a plurality of illuminators forming an array of illuminators distributed in a horizontal row and a straight line, each illuminator being periodically addressable with a display signal value, the value representing display data during the image period; current adjustment a transducer connected in series with each of the illuminators of the array to form an illuminator/modulator in series, the modulator comprising a source, a drain, and a gate, the modulator being capable of being bypassed by a drain current to supply power The illuminator, because the voltage between one of the drain and the source and the gate is greater than or equal to the trip threshold voltage of the modulator; the charge storage capacitor can maintain the control voltage for each modulation during the image period a gate of the device; a selection mechanism capable of selecting an illuminator of the same course; and a driving mechanism for illuminating the illumination, in each straight line, including an adjustable power supply mechanism for supplying the illuminator, the output of which is connected to the direct illumination One of the series end of the modulator/modulator, and at least one operational amplifier for controlling the corresponding modulator, having an inverting input, a non-inverting input and an output, and selectively coupling to the modulator In the case of an optical device, the amplifier output can be connected to the gate of each of the straight modulators to apply the control voltage to the gate; and is characterized by one of a non-inverting input and an inverting input of the operational amplifier, Connected to the output of the adjustable power supply mechanism to be coupled to the gate of the modulator, coupled to the output of the operational amplifier, forming a feedback loop of the operational amplifier when one of the illuminators is selected, and the adjustable power supply mechanism includes The variable voltage generator continuously supplies power to the full set of illuminators in the straight line during the image period, and the voltage of the variable voltage generator changes according to the value of the display signal. The device of claim 1, wherein one of the ends of the straight illuminators/modulators connected in series is connected to an output of the power supply mechanism, corresponding to a drain or a source of the modulator. The apparatus of claim 1 or 2, wherein one of the non-inverting input and the inverting input of the operational amplifier is connected to the output, and is capable of receiving a signal, depending on the value of the display signal, the value is intended to be addressed from the The illuminator selected directly. The device of claim 1, wherein the variable voltage occurs Providing the same driving signal by one of the terminals of the illuminators/modulators connected in series with one of the straight lines, continuously supplying power to the full set of illuminators in a straight line, the driving signals being previously addressed and during the image period At present, the total value of the display signal values of the full set of illuminators to be located in the straight line is determined. The device of claim 4, wherein the drive generator comprises a display voltage generator and a series of resistive elements, wherein the voltage generator is adapted to generate a voltage, depending on the previous address and is currently addressed in a straight line during the image period. The total display signal value of the full set of illuminators depends on the total. A device as claimed in claim 5, wherein there is no switching mechanism between the output of the power supply mechanism and the respective ends of the series of illuminators/modulators in a straight line. The device of claim 5, wherein the voltage generator is coupled to the resistive element to deliver a drive current based on the following relationship: Where R is a resistive element, V _{ref n} is a reference voltage associated with illuminator n, V _{data n} is the display voltage value addressed to illuminator n, and p is the total number of in-line illuminators. The device of claim 1, wherein the driving mechanism further comprises a reference generator capable of transmitting a reference signal to the other of the inverting input and the non-inverting input of the operational amplifier. A device as claimed in claim 8 wherein each illuminator exhibits particular electrical and/or optical properties, wherein each reference signal value depends on the electrical and/or optical properties. A device of claim 8 wherein each illuminator is associated with illumination of a color, and wherein the reference signal is modulatable as a function of a color assigned to the selected illuminator. The device of claim 8, wherein the illuminator comprises a plurality of adjacent illuminators adapted to emit different colors of light, and for each complex number, the ginseng The test signal is deployed in the plurality of illuminators in such a manner that the illuminators are addressed by the same display signal value, and the plurality of white tones can be realized. The device of claim 1, wherein the driving mechanism further comprises a data storage mechanism capable of storing the value of the display signal and addressing the illuminators during the image period. A method for controlling an active matrix image display device, the display device comprising a plurality of illuminators, forming an array of illuminators distributed in a horizontal row and a straight line, each illuminator being capable of being periodically addressed by using a display signal value, the value representing during the image period Display data; the current modulator includes a source, a drain, a gate, one of the drain or source of each modulator, and is connected in series with the illuminator of the array to form an illuminator/modulator including both ends in series a selection mechanism capable of selecting a row of emitters; a charge storage capacitor capable of maintaining a control voltage at the gate or modulators during the image; a drive mechanism for the straight-line illuminator illumination, including at least one operational amplifier, having Inverting input, non-inverting input and output; the method comprises the steps of: transmitting a selection signal to the horizontal illuminator by using a selection mechanism; and driving the driving signal to one of the series end of each illuminator/modulator in a straight line by using a driving mechanism Using a driving mechanism, applying a control signal to a gate coupled to each of the modulators of the selected illuminator; characterized in that it further comprises the following steps: a column illuminator, coupled to a gate of the modulator coupled to the output of the operational amplifier, and coupled to one of the non-inverting input and the inverting input of the operational amplifier output of the illuminator supply mechanism to form a feedback loop of the operational amplifier The drive signal depends on the total display signal value of the full set of illuminators that are addressed during the image period.