CN116543690A - Pixel structure of miniature light-emitting device based on induced electric field and driving method - Google Patents

Abstract

The invention provides a pixel structure of a miniature luminescent device based on an induced electric field, each pixel unit in the pixel structure comprises two miniature inductive luminescent devices sharing a line gating line and a data line, the two miniature inductive luminescent devices are respectively in a luminescent state alternately in a positive half period and a negative half period of alternating current driving voltage of a miniature luminescent device power supply, the brightness effect and the brightness stabilizing effect of the pixel structure observed by human eyes are optimized by utilizing the visual persistence characteristic of the human eyes, and the power consumption of a circuit is reduced; in the miniature light-emitting device, a plurality of pixel units form a lattice structure, and pixel units in the same row share the same row of gating lines; the invention can solve the problems of uneven light emission of a single pixel of the miniature light emitting device, too many data lines in a driving circuit, crowded wiring and the like.

Description

A pixel structure and driving method of a micro light-emitting device based on an induced electric field

technical field

The invention relates to the technical field of pixel driving, in particular to a pixel structure of a miniature light-emitting device based on an induced electric field.

Background technique

Micro Light Emitting Diode (Micro-LED) displays use micron-sized (generally less than 50 μm) inorganic LED devices as light-emitting pixels to realize active light-emitting matrix displays. In terms of display technology principles, Micro-LED, Organic light emitting diodes (OLED), and Quantumdot light emitting diodes (.QLED) are all active light emitting display technologies. However, unlike OLED and QLED display technologies, Micro-LED displays use LED light-emitting chips such as inorganic Ga-N, which have excellent luminous performance and long life. The industrialization of Micro-LED is mainly faced with the problems of integration process and related materials.

The simple device structure of non-carrier injection light-emitting diodes is expected to be applied to new micro-display technologies such as Micro-LEDs and nano-pixel light-emitting displays. The coupling between the electrodes is solved, and the problem of precise docking of the electrode chip under the tiny size is solved.

In the field of flat panel display technology, micro light-emitting devices have many advantages, the most notable of which are low power consumption, high brightness, ultra-high definition, high color saturation, faster response speed, longer service life and Higher work efficiency, etc., is a transformative new display technology, which is expected to replace almost all applications of TFT liquid crystal displays in the field of flat panel displays.

Contents of the invention

The invention proposes a pixel structure of a micro-light-emitting device based on an induced electric field, which can solve the problems of uneven light emission of a single pixel of the micro-light-emitting device, too many data lines in a driving circuit, and crowded wiring.

The present invention adopts the following technical solutions.

A pixel structure of a miniature light-emitting device based on an induced electric field, each pixel unit in the pixel structure includes two miniature inductive light-emitting devices sharing a row gate line and a data line, and the two miniature inductive light-emitting devices are respectively connected to The AC driving voltage of the power supply of the micro light-emitting device is in the light-emitting state alternately in the positive half cycle and negative half cycle, using the persistence of human vision to optimize the brightness effect and brightness stabilization effect of the pixel structure observed by the human eye, and reduce the power consumption of the circuit ;

In the micro light emitting device, a plurality of pixel units form a dot matrix structure, and the same row of pixel units share the same row of gate lines.

The miniature inductive light emitting device includes a single-end carrier injection type inductive light emitting device and a non-carrier injection type inductive light emitting device; the miniature inductive light emitting device in the pixel unit is a first miniature inductive light emitting device, a second miniature inductive light emitting device ,

The pixel structure includes a plurality of row gate lines arranged along a first direction, a plurality of data lines arranged along a second direction, and a plurality of pixels periodically arranged along the first direction and the second direction unit, wherein said first direction is different from said second direction;

The light-emitting unit is an LED device, the anode of which is connected to the first electrode, the cathode is connected to the second electrode, the third electrode is connected to the row electrode, and the fourth electrode is connected to the data electrode;

The first electrode is opposed to the third electrode to form a first capacitor, and the second electrode is opposed to the fourth electrode to form a second capacitor;

In a single pixel unit, the row electrodes of two miniature electroluminescent devices are connected to form a common row electrode terminal, and the column electrodes of two miniature electroluminescent devices are connected and externally connected to a data line to form a common data electrode terminal;

The power supply forms an induced electric field by applying an AC driving voltage to the row electrode and the data electrode, and the induced electric field drives the micro light emitting device to emit light.

The first half sub-period of each pixel unit drives the first miniature inductive light-emitting device to emit light, and the second half sub-period drives the second miniature inductive light-emitting device to emit light; that is, the first light-emitting unit of the miniature inductive light-emitting device emits light in the positive half cycle of the AC driving voltage, The second light emitting unit emits light in the negative half cycle of the AC driving voltage.

The electrodes of the first miniature inductive light emitting device are positively connected, the electrodes of the second miniature inductive light emitting device are connected in reverse, the anode of the first miniature inductive light emitting device is connected to the cathode of the second miniature inductive light emitting device, and the cathode of the first miniature inductive light emitting device is connected to the anode of the second miniature inductive light emitting device .

When the pixel structure is driven, among two adjacent pixel units, the first miniature inductive light-emitting device of the first pixel unit is controlled by the first row gate line in the first direction and the gate line in the second direction. The first data line is controlled, and the second miniature inductive light-emitting device is controlled by the first row gate line in the first direction and the first data line in the second direction; in the second pixel unit, the first The micro light emitting device is composed of the first row gate line in the first direction and the second data line in the second direction, and the second micro inductive light emitting device is composed of the first row gate line in the first direction and the second data line control of the second direction.

The power supply of the light-emitting device drives the first miniature inductive light-emitting device and the second miniature inductive light-emitting device to emit light according to a preset cycle through the positive and negative cycles of the driving waveform of the AC driving voltage in a time-sharing driving manner, using the integral of the human eye and the human body The persistent effect of eye vision makes the luminance of the first miniature inductive light-emitting device and the second miniature inductive light-emitting device superimpose in human vision to increase the brightness of the pixel unit.

The driving waveform includes a sine wave, a triangle wave, a square wave, a pulse wave or a combination of the above waveforms.

The light emitting color of the light emitting device includes red, green, blue or white.

At least one of the upper electrode and the lower electrode of the light-emitting device is a transparent electrode; the material of the transparent electrode includes graphene, indium tin oxide, carbon nanotubes, silver nanowires, copper nanowires or a combination of the above materials; the non-transparent electrode The materials used include gold, silver, aluminum, copper or a combination of the above materials.

The single cycle response cycle of the light emitting device is less than 0.01 second.

The invention provides a novel pixel structure aimed at non-electrical contact and no external carrier micro-light-emitting devices, which can solve the problems of uneven light emission of a single pixel, too many data lines in a driving circuit, crowded wiring, and the like.

In the present invention, two miniature inductive light-emitting devices connected positively and negatively are placed in a unit pixel, and according to the unique time-domain light-emitting characteristics of the inductive light-emitting device, the two micro-light-emitting devices in a single pixel are realized to emit light sequentially, increasing the brightness of the device and improving the display. As a result, in the same unit pixel, two miniature inductive light-emitting devices share the same row gate line and data line, and row gate lines are shared between the same row of pixel units in the array. , using an induced electric field to drive light emission can simplify the line connection of the display device and avoid a mass transfer process and a complicated bonding process.

The present invention can improve display brightness and reduce energy consumption by connecting two miniature inductive light-emitting devices in a single pixel unit forward and reversely, and the devices are lit through electromagnetic coupling, thereby prolonging the life of the light-emitting device and greatly reducing the size of the chip. Realize Micro-LED level display.

In the present invention, two light-emitting miniature inductance light-emitting devices in a single pixel share the row gate line and the data line, and the same row gate line is shared by the same row of pixel units in the dot matrix, which reduces the use of data lines or row gate lines. The driving method periodically drives the two light-emitting devices in the pixel in sequence, using the persistence of human vision to reduce the power consumption of the circuit. The half-period time-domain luminescence characteristics enhance the display effect and reduce the AC driving frequency.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

Accompanying drawing 1 is a schematic diagram of an exemplary pixel structure of an embodiment of the present invention;

Accompanying drawing 2 is a schematic diagram of an exemplary device structure of an embodiment of the present invention;

Accompanying drawing 3 is the luminescence time-domain characteristic diagram under a kind of sinusoidal driving waveform of the embodiment of the present invention;

Fig. 4 is a time-domain characteristic diagram of light emission under a square wave driving waveform according to an embodiment of the present invention.

Detailed ways

As shown in the figure, a pixel structure of a miniature light-emitting device based on an induced electric field, each pixel unit in the pixel structure includes two miniature inductive light-emitting devices sharing a row gate line and a data line, and two miniature inductive light-emitting devices The inductive light-emitting device is in the light-emitting state alternately in the positive half-cycle and negative half-cycle of the AC driving voltage of the power supply of the micro-light-emitting device, and the brightness effect and brightness stabilization effect of the pixel structure observed by the human eye are optimized by using the persistence of vision of the human eye, and Reduce circuit power consumption;

In the micro light emitting device, a plurality of pixel units form a dot matrix structure, and the same row of pixel units share the same row of gate lines.

The miniature inductive light emitting device includes a single-end carrier injection type inductive light emitting device and a non-carrier injection type inductive light emitting device; the miniature inductive light emitting device in the pixel unit is a first miniature inductive light emitting device, a second miniature inductive light emitting device ,

The pixel structure includes a plurality of row gate lines arranged along a first direction, a plurality of data lines arranged along a second direction, and a plurality of pixels periodically arranged along the first direction and the second direction unit, wherein said first direction is different from said second direction;

The light-emitting unit is an LED device, the anode of which is connected to the first electrode, the cathode is connected to the second electrode, the third electrode is connected to the row electrode, and the fourth electrode is connected to the data electrode;

The first electrode is opposed to the third electrode to form a first capacitor, and the second electrode is opposed to the fourth electrode to form a second capacitor;

In a single pixel unit, the row electrodes of two miniature electroluminescent devices are connected to form a common row electrode terminal, and the column electrodes of two miniature electroluminescent devices are connected and externally connected to a data line to form a common data electrode terminal;

The power supply forms an induced electric field by applying an AC driving voltage to the row electrode and the data electrode, and the induced electric field drives the micro light emitting device to emit light.

The first half sub-period of each pixel unit drives the first miniature inductive light-emitting device to emit light, and the second half sub-period drives the second miniature inductive light-emitting device to emit light; that is, the first light-emitting unit of the miniature inductive light-emitting device emits light in the positive half cycle of the AC driving voltage, The second light emitting unit emits light in the negative half cycle of the AC driving voltage.

The electrodes of the first miniature inductive light emitting device are positively connected, the electrodes of the second miniature inductive light emitting device are connected in reverse, the anode of the first miniature inductive light emitting device is connected to the cathode of the second miniature inductive light emitting device, and the cathode of the first miniature inductive light emitting device is connected to the anode of the second miniature inductive light emitting device .

When the pixel structure is driven, among two adjacent pixel units, the first miniature inductive light-emitting device of the first pixel unit is controlled by the first row gate line in the first direction and the gate line in the second direction. The first data line is controlled, and the second miniature inductive light-emitting device is controlled by the first row gate line in the first direction and the first data line in the second direction; in the second pixel unit, the first The micro light emitting device is composed of the first row gate line in the first direction and the second data line in the second direction, and the second micro inductive light emitting device is composed of the first row gate line in the first direction and the second data line control of the second direction.

The power supply of the light-emitting device drives the first miniature inductive light-emitting device and the second miniature inductive light-emitting device to emit light according to a preset cycle through the positive and negative cycles of the driving waveform of the AC driving voltage in a time-sharing driving manner, using the integral of the human eye and the human body The persistent effect of eye vision makes the luminance of the first miniature inductive light-emitting device and the second miniature inductive light-emitting device superimpose in human vision to increase the brightness of the pixel unit.

The driving waveform includes a sine wave, a triangle wave, a square wave, a pulse wave or a combination of the above waveforms.

The light emitting color of the light emitting device includes red, green, blue or white.

At least one of the upper electrode and the lower electrode of the light-emitting device is a transparent electrode; the material of the transparent electrode includes graphene, indium tin oxide, carbon nanotubes, silver nanowires, copper nanowires or a combination of the above materials; the non-transparent electrode The materials used include gold, silver, aluminum, copper or a combination of the above materials.

The single cycle response cycle of the light emitting device is less than 0.01 second.

Example:

Please refer to FIG. 1 , which is a schematic diagram illustrating a pixel structure of an embodiment. The pixel structure includes a row gate line, two data lines and two pixel units. The row gate lines are arranged along the first direction R1, the two data lines are arranged along the second direction R2, and two adjacent pixel units are arranged along the first direction. The first direction R1 is different from the second direction R2.

As shown in FIG. 1 , the first pixel unit includes a first miniature inductive light emitting device and a second miniature inductive light emitting device, and the second pixel unit includes a third miniature inductive light emitting device and a fourth miniature inductive light emitting device.

In Fig. 1, in the first pixel unit, the first miniature inductive light emitting device is positively connected, and the second miniature inductive light emitting device is reversely connected; in the second pixel unit, the third miniature inductive light emitting device is positively connected, and the fourth miniature inductive light emitting device catch.

The first micro-inductor light-emitting device is respectively driven by the first row gate line and the first data line, and is used to drive the first micro-inductor according to the data signal of the first data line under the control of the first row gate line Light emitting devices.

The second micro-inductor light-emitting device is respectively driven by the first row gate line and the first data line, and is used to drive the second micro-inductor according to the data signal of the first data line under the control of the first row gate line Light emitting devices.

The third micro-inductor light-emitting device is respectively driven by the first row gate line and the first data line, and is used to drive the third micro-inductor according to the data signal of the second data line under the control of the first row gate line Light emitting devices.

The fourth micro-inductor light-emitting device is respectively driven by the first row gate line and the first data line, and is used to drive the fourth micro-inductor according to the data signal of the second data line under the control of the first row gate line Light emitting devices.

Optionally, the first to fourth miniature electroluminescent devices may be double-terminal carrier injection micro LEDs, single-terminal non-carrier injection micro LEDs or non-carrier injection micro LEDs.

Fig. 2 is a structural diagram of the miniature inductive light-emitting device, the anode of the first light-emitting unit LED is connected to the first electrode, the cathode is connected to the second electrode, the third electrode is connected to the row electrode, and the fourth electrode is connected to the data electrode.

As shown in FIG. 2 , the first electrode is opposite to the third electrode to form a first capacitor, and the second electrode is opposite to the fourth electrode to form a second capacitor. By applying an AC driving voltage to the row electrode and the data electrode, the micro-device emits light under the induced electric field.

Figure 3 is the time-domain luminescence characteristic diagram of the micro-inductive light-emitting device. The dotted line represents the driving waveform added by the driving circuit. When the AC driving circuit is a sine wave, the micro-inductive light-emitting device only emits light in the positive half cycle. The relationship between the luminous intensity of the device and time, the luminous intensity gradually increases in the positive half cycle of the sine wave.

It can be seen that in FIG. 3 , the miniature electroluminescent device emits light only in the positive half cycle of the sine wave, and does not emit light in the negative half cycle of the sine wave.

Figure 4 is the time-domain luminescence characteristic diagram of the micro-inductive light-emitting device. The dotted line represents the driving waveform added by the driving circuit. When the AC driving circuit is a square wave, the micro-inductive light-emitting device only emits light in the positive half cycle. The relationship between the luminous intensity of the device and time, the luminous intensity gradually increases in the positive half cycle of the square wave.

According to the emission time-domain characteristics of the micro-inductor light-emitting device, in a single waveform driving cycle, in the positive half cycle, the positively connected micro-inductor light-emitting device emits light, and the reverse-connected micro-inductor light-emitting device in the same unit pixel does not emit light, and in the negative half cycle Inside, the reversely connected miniature inductive light-emitting device emits light, and the positively connected miniature inductive light-emitting device in the same pixel does not emit light.

The miniature inductive light-emitting device of the present invention is driven by an external AC voltage, without external carrier injection, and radiates and emits light by recombination of carriers inside the device, and the driving electrode of the light-emitting device has no direct ohmic contact with an external circuit.

The response speed of the miniature electroluminescent device is very fast, and the period of the required AC driving waveform is particularly small, less than 0.01 second.

In the present invention, the brightness of the overall display is changed by controlling the frequency of different miniature inductive light-emitting devices in the same pixel.

In the invention, each pixel unit is always emitting light stably during the light emitting period, which can make up for the shortcomings of a single miniature inductive light emitting device that is unstable in light emission and uneven in display brightness.

The present invention adopts a time-sharing driving method according to the persistent visual effect of human eyes. When the human eye watches, the image is formed on the object, and it is input to feel the image of the object. But when the object is removed, the impression of the optic nerve on the object will not disappear immediately, but will last for 0.1 second. The phenomenon of persistence of vision (Persistence of vision) is that the vision produced by light on the retina remains after the light stops acting. Therefore, in the pixel driving circuit, the size of the cycle of the driving circuit is adjusted, and the size of the entire cycle is adjusted to be less than 0.1 second, so that the effect of continuous light emission of the micro light emitting devices in the array can be obtained.

In summary, the present invention can reduce the use of data lines by changing the pixel structure of the light-emitting device, by adjusting the circuit drive waveforms of rows and columns, and utilizing the persistence of human vision to reduce energy consumption. The time domain characteristic of luminescence improves the brightness stability and improves the display effect. By controlling the driving frequency and time, the contrast is adjusted and the display gray level is improved.

The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent transformations made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in related technical fields, are all included in the same principle. Within the scope of patent protection of the present invention.

Claims (10)

1. A pixel structure based on a miniature light-emitting device of an induced electric field, characterized in that: each pixel unit in the pixel structure contains two miniature inductive light-emitting devices sharing row gate lines and data lines, two The micro-inductive light-emitting device is in the light-emitting state alternately in the positive half cycle and negative half cycle of the AC driving voltage of the power supply of the micro light-emitting device, and the brightness effect and brightness stabilization effect of the pixel structure observed by the human eye are optimized by using the persistence of vision of the human eye. And reduce circuit power consumption; In the micro light emitting device, a plurality of pixel units form a dot matrix structure, and the same row of pixel units share the same row of gate lines. 2. The pixel structure of a miniature light-emitting device based on an induced electric field according to claim 1, wherein the miniature inductive light-emitting device includes a single-terminal carrier injection inductive light-emitting device, a non-carrier injection type inductive light emitting device; the miniature inductive light emitting device in the pixel unit is a first miniature inductive light emitting device and a second miniature inductive light emitting device, The pixel structure includes a plurality of row gate lines arranged along a first direction, a plurality of data lines arranged along a second direction, and a plurality of pixels periodically arranged along the first direction and the second direction unit, wherein said first direction is different from said second direction; The light-emitting unit is an LED device, the anode of which is connected to the first electrode, the cathode is connected to the second electrode, the third electrode is connected to the row electrode, and the fourth electrode is connected to the data electrode; The first electrode is opposed to the third electrode to form a first capacitor, and the second electrode is opposed to the fourth electrode to form a second capacitor; In a single pixel unit, the row electrodes of two miniature electroluminescent devices are connected to form a common row electrode terminal, and the column electrodes of two miniature electroluminescent devices are connected and externally connected to a data line to form a common data electrode terminal; The power supply forms an induced electric field by applying an AC driving voltage to the row electrode and the data electrode, and the induced electric field drives the micro light emitting device to emit light. 3. The pixel structure of a micro-light-emitting device based on an induced electric field according to claim 2, wherein the first half sub-period of each pixel unit drives the first micro-inductor light-emitting device to emit light, and the second half sub-period drives The second miniature inductive light-emitting device emits light; that is, the first light-emitting unit of the miniature inductive light-emitting device emits light in the positive half cycle of the AC driving voltage, and the second light-emitting unit emits light in the negative half cycle of the AC driving voltage. 4. The pixel structure of a miniature light-emitting device based on an induced electric field according to claim 3, characterized in that: the electrode of the first miniature inductive light-emitting device is positively connected, the electrode of the second miniature inductive light-emitting device is reversely connected, and the first miniature inductor The anode of the light-emitting device is connected to the cathode of the second miniature inductive light-emitting device, and the cathode of the first miniature inductive light-emitting device is connected to the anode of the second miniature inductive light-emitting device. 5. The pixel structure of a micro light-emitting device based on an induced electric field according to claim 2, characterized in that: when the pixel structure is driven, among two adjacent pixel units, the first pixel unit The first miniature inductive light emitting device is controlled by the first row gate line in the first direction and the first data line in the second direction, and the second miniature inductive light emitting device is controlled by the first row gate line in the first direction row gate line and the first data line in the second direction; in the second pixel unit, the first micro light emitting device is controlled by the first row gate line in the first direction and the second direction The second data line of the second miniature inductive light emitting device is controlled by the first row gate line in the first direction and the second data line in the second direction. 6. The pixel structure of a micro light-emitting device based on an induced electric field according to claim 2, characterized in that: the power supply of the light-emitting device uses the positive and negative cycles of the driving waveform of the AC driving voltage to drive in a time-sharing manner , driving the first miniature inductive light emitting device and the second miniature inductive light emitting device to emit light in a preset period, using the integral of the human eye and the persistence of vision effect of the human eye to make the luminous brightness of the first miniature inductive light emitting device and the second miniature inductive light emitting device Superimposed in human vision to increase the brightness of the pixel unit. 7 . The pixel structure of a micro light emitting device based on an induced electric field according to claim 1 , wherein the driving waveform comprises a sine wave, a triangle wave, a square wave, a pulse wave or a combination of the above waveforms. 8 . The pixel structure of a micro light emitting device based on an induced electric field according to claim 1 , wherein the light emitting color of the light emitting device includes red, green, blue or white. 9. The pixel structure of a micro light-emitting device based on an induced electric field according to claim 1, wherein at least one of the upper electrode and the lower electrode of the light-emitting device is a transparent electrode; the material of the transparent electrode includes Graphene, indium tin oxide, carbon nanotubes, silver nanowires, copper nanowires or a combination of the above materials; materials for the non-transparent electrodes include gold, silver, aluminum, copper or a combination of the above materials. 10 . The pixel structure of a micro light-emitting device based on an induced electric field according to claim 1 , wherein a single cycle response period of the light-emitting device is less than 0.01 second. 11 .