Patent Application
20240063198
The application relates to an electric circuit, a display apparatus, and applications thereof, and more particularly to a pixel unit and a display apparatus applying the same.
Display technology has become ubiquitous in our daily life, which convers widespread applications, such as smartphones, tablets, desktop monitors, TVs, data projectors, and augmented reality/virtual reality devices. Micro-LEDs (μLEDs) and mini-LEDs (mLEDs) have emerged as light-emitting devices for next-generation displays, the former is particularly attractive for transparent displays and high luminance displays, while the latter can serve either as a locally dimmable backlight for high dynamic range (HDR) LCDs or as emissive displays. Both mLEDs and μLEDs offer ultra-miniaturized size and long lifetimes. However, there may still remain challenges on power consumption of mLED/μLED displays, which will definitely affect the efficiency.
One embodiment of the present application is to provide a subpixel unit, wherein the subpixel unit includes a first thin film circuit unit and a first light emitting device. The first thin film circuit unit includes a first driving device having a first terminal, a second terminal, and a control terminal. The first terminal can receive a first signal. The control terminal can receive a second signal to control on/off of the first driving device for allowing the first signal transmitted to the second terminal. The first light emitting device includes a plurality of first light-emitting elements connected in series and connected to the second terminal, wherein a total voltage of the plurality of first light-emitting elements is not less than ⅓ of a saturation voltage of the first driving device.
Another embodiment of the present application is to provide a pixel unit including a subpixel unit including a first thin film circuit unit and a first light emitting device. The first thin film circuit unit includes a first driving device having a first terminal, a second terminal, and a control terminal. The first terminal can receive a first signal. The control terminal can receive a second signal to control on/off of the first driving device for allowing the first signal transmitted to the second terminal. The first light emitting device includes a plurality of first light-emitting elements connected in series and connected to the second terminal, wherein a total voltage of the plurality of first light-emitting elements is not less than ⅓ of a saturation voltage of the first driving device.
According to the above embodiments, a pixel unit and a display apparatus applying the same are provided, wherein the pixel unit includes a first thin film circuit unit and a first light emitting device connected to a driving device of the first thin film circuit unit, a plurality of first light-emitting elements are connected in series to serve as the first light emitting device, and a total voltage of the plurality of first light-emitting elements is limited not less than ⅓ of a saturation voltage of the driving device for turn on the first light emitting device.
The above and other aspects of the application will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment(s). The following description is made with reference to the accompanying drawings. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
The present application provides a pixel unit and a display apparatus applying the same for driving mLED/μLED displays more efficiently to achieve the effective luminance. The above and other aspects of the application will become better understood by the following detailed description of the preferred but non-limiting embodiment(s). The following description is made with reference to the accompanying drawings:
Several embodiments of the present application are disclosed below with reference to accompanying drawings. However, the structure and contents disclosed in the embodiments are for exemplary and explanatory purposes only, and the scope of protection of the present application is not limited to the embodiments. It should be noted that the present application does not illustrate all possible embodiments, and anyone skilled in the technology field of the application will be able to make suitable modifications or changes based on the specification disclosed below to meet actual needs without breaching the spirit of the application. The present application is applicable to other implementations not disclosed in the specification.
Typically, an LED display includes a plurality of LED subpixel units each including an LED driven or controlled by a thin-film-transistor (TFT), all together arranged to form a pixel array. The LED may be a mini LED (mLED) or a micro LED (μLED). The LED display may be a mLED display or a μLED display. For example,
Each of the switching TFT (TS) and the driving TFT (TD) includes a gate electrode, a source electrode, and a drain electrode. The driving TFT (TD) can be implemented as an NMOS thin-film transistor, while the switching TFT (TS) can be implemented as a PMOS thin-film transistor. It is, however, to be noted that the technical idea of the present application is not limited thereto. For example, the switching TFT (TS) can be implemented as an NMOS thin-film transistor, while the driving TFT (TD) can be implemented as a PMOS thin-film transistor.
In an embodiment, the switching TFT (TS) is implemented as an NMOS thin-film transistor, while the driving TFT (TD) is implemented as a PMOS thin-film transistor. The source electrode of the switching TFT (TS) is connected to a data voltage line (Vdata). The drain electrode of the switching TFT (TS) is connected to the gate of the driving TFT (TD) to control the on/off of the driving TFT (TD). The source electrode of the driving TFT (TD) is connected to a power source line (VDD). The drain electrode of the driving TFT (TD) is connected to the LED. The driving TFT (TD) can regulate the current flowing to the LED through regulating the gate electrode of the driving TFT (TD) by the data voltage line (Vdata). The mLED/μLED can emit light when the driving TFT (TD) is turn on by the data voltage (Vdata) to allow current (I) flowing to the mLED/μLED under a voltage (VDS). One end of the capacitor CS is connected to the power source line (VDD) and another end of the capacitor CS is connected to a node between the drain electrode of the switching TFT (TS) and the gate electrode of the driving TFT (TD). The switching TFT (TS) performs switching operation in response to a scan signal supplied through SCAN so that the data voltage supplied through the data voltage line (Vdata) is stored in the capacitor (CS) and a signal is supplied to the gate electrode of the driving TFT (TD). The gate electrode of the driving TFT (TD) is connected to the drain electrode of the switching TFT (TS). The driving TFT (TD) includes a source electrode connected to the power source (VDD) and a drain electrode connected to the mLED/μLED. The drain electrode of the driving TFT (TD) is connected to a positive terminal of the mLED/μLED and a negative terminal of the mLED/μLED is connected to the ground voltage.
In an amorphous silicon (a-Si) TFT array, the voltage drop on the power source line (VDD) is about 12V. VF is the mLED/μLED forward voltage. I is the current through the driving TFT (TD) and mLED/μLED. It is well known that, in operation, the driving TFT (TD) generally consumes more power (VDS×I) than that of the mLED/μLED (VF×I). As the LED size shrinks, the luminance of each subpixel may reduce. It may require to increase the luminance of the mLED/μLED. The mLED/μLED typically has a forward voltage (VF) of 2 V to 4 V. The mLED/μLED cannot be connected directly to the voltage sources. Therefore, the mLED/μLED is connected in series with some additional devices (such as resistors) to reduce the drain-to-source voltage (VDS) of the driving TFT (TD) for balancing the power consumption ratio between the TFT and LED (VDS/VF) for the purpose of driving the pixel array of the mLED/μLED displays more efficiently. Therefore, a considerable part of the operating voltage is dropped across the series resistor. This leads to a low efficiency since the part of the operating voltage which is dropped across the series resistor is not utilized for generating radiation.
The first thin film circuit unit 201 further includes a data line 204, a scan line 205, a power source (VDD) 206, a switching device 207, and a capacitor 208. The power source (VDD) 206 is connected to the terminal 203a to provide the signal S11. The data line 204 is connected to the control terminal 203c through the switching device 207 to provide the second signal S12. The switching device 207 includes a gate terminal 207c. The scan line 205 is connected to the gate terminal 207c of the switching device 207 for controlling whether the second signal S12 can pass through the switching device 207 and reach to the control terminal 203c of the driving device 203.
One end of the first light emitting device 202 (the plurality of first light-emitting elements 202a, 202b, and 202c is connected in series) is connected to the terminal 203b of the driving device 203, the other end of the first light emitting device 202 is grounded. One end of the capacitor 208 is connected to the power source (VDD) 206, and the other end of the capacitor 208 is connected to the control terminal 203c of the driving device 203 and the switching device 207 through a node therebetween.
In some embodiments of the present application, the driving device 203 is a thin film transistor (TFT), and the first light emitting device 202 is a p-LED device with a size (length or width in the top view) ranging from 100 μm to 10 μm and having a plurality of p-LED elements (serving as the first light-emitting elements 202a, 202b, and 202c) formed on a substrate (not shown). In another embodiment of the present application, the first light emitting device 202 is a mini-LED (mLED) device with a size (length or width in the top view) ranging from 200 μm to 100 μm and having a plurality of mini-LED elements (serving as the first light-emitting elements 202a, 202b, and 202c) formed on a substrate (not shown).
In addition, the first light-emitting elements 202a, 202b, and 202c involved in the first light emitting device 202 may be identical to or different from each other in terms of size, materials and so on. In some embodiments, the plurality of first light-emitting elements 202a, 202b, and 202c all emit lights with substantially the same wavelength. For example, in one embodiment, the first light-emitting elements 202a, 202b, and 202call emit blue light with wavelength ranging from 400 nm to 500 nm, red light with wavelength ranging from 620 nm to 750 nm, or green light with wavelength ranging from 495 nm to 570 nm. In yet another embodiment, the first light-emitting elements 202a, 202band 202c all emit invisible light, such as Ultraviolet (UV) with wavelength ranging from 100 nm to 400 nm.
According to exemplary embodiments, all of red (R), green (G), and blue (B) light can be produced by using multiple mLEDs/μLEDs producing blue light. Red light is provided by disposing red phosphor on one of the multiple mLEDs/μLEDs and green light is provided by disposing green phosphor on another of the multiple mLEDs/μLEDs. With the mLEDs/μLEDs implemented based on blue light having a similar driving voltage, the driver circuit can be simplified.
Although the first light emitting device 202 as depicted in
From the circuit illustrated in
Power=PLED+PTFT=(VF+VDS)×I
I is the current flowing through the first light emitting device 202 and the driving device 203, VF is the forward voltage of the first light emitting device 202, and VDS is the drain to source voltage of the driving device 203. In operation, the first light emitting device 202 is a constant current driving device, and the driving device 203 serves as a current source. The gate-to-source voltage (VGS) of the driving device 203 controls the current I, and the current I determines the emittance of the first light emitting device 202. As the forward voltage of the light emitting device 202 is increased, less power is consumed on the driving device 203 and more power is consumed on the first light emitting device 202.
In some embodiment, the light emitting device 302 can be applied to the first light emitting device 202 in the subpixel unit 200 as depicted in
For example, the first light-emitting element 302aincludes a first n-type semiconductor layer 3021a, a first active layer 3022a, and a first p-type semiconductor layer 3023a stacked in sequence along a vertical direction (Z direction) on the substrate 310.
The second light-emitting element 302b includes a second n-type semiconductor layer 3021b, a second active layer 3022b, and a second p-type semiconductor layer 3023b stacked in sequence along the vertical direction (Z direction) on the first light-emitting element 302a.
The third light-emitting element 302c includes a third n-type semiconductor layer 3021c, a third active layer 3022c, and a third p-type semiconductor layer 3023c stacked in sequence along the vertical direction (Z direction) on the second light-emitting element 302b.
A first tunnel junction 302t1 may be formed between the first light-emitting element 302a and the second light-emitting element 302b by means of a p-type semiconductor layer and an n-type semiconductor layer. A second tunnel junction 302t2 may be formed between the second light-emitting element 302b and the third light-emitting element 302c by means of a p-type semiconductor layer and an n-type semiconductor layer.
In the present embodiment, the contact layers 314 and 319 are formed at the opposite sides of the stack structure of the light emitting device 302. The contact layer 314 is electrically connected to the first n-type semiconductor layer 3021a of the first light-emitting element 302a through the substrate 310, and the contact layer 319 is electrically contact to the third p-type semiconductor layer 3023c of the third light-emitting element 302c.
The contact layers 314 and 319 may include Cu, W, Al, Ti, Ta, or the arbitrary combinations thereof. The tunnel junctions 302t1, 302t2 can be formed by stacking the p-type semiconductor layer and the n-type semiconductor layer through a metal-organic chemical vapor deposition (MOCVD) technology. Each of the tunnel junctions 302t1, 302t2 includes a heavily doped p-type semiconductor layer and a heavily doped n-type semiconductor layer. Alternatively, the tunnel junction 302t1 or 302t2 can be a layer constituted by transparent conductive material (such as ITO) formed by glue bonding or CVD technology.
The substrate 310 comprises a conductive substrate. The substrate 310 comprises a thickness within a range between 50 μm˜250 μm, between 80 μm˜200 μm in another embodiment, or between 100 μm˜150 μm in a further embodiment.
In an embodiment of the present application, the metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HYPE), physical vapor deposition (PVD), or ion plating method is performed to form the light-emitting elements 302a, 302b, and 302c with photoelectrical characteristics on the substrate 310, wherein the physical vapor deposition method comprises sputtering or evaporation. The light-emitting elements 302a, 302b, and 302ceach includes a thickness larger than 3 μm and less than 6 μm, or larger than 4 μm and less than 5 μm.
The wavelength of the light emitted from the light-emitting elements 302a, 302b, or 302c is adjusted by changing the physical and chemical composition of the active layers 3022a, 3022b, or 3022c. The material of the active layers 3022a, 3022b, or 3022c comprises III-V group semiconductor materials, such as AlxInyGa(1−x−y)N, AlxGa(1−x)As, or AlxInyGa(1−x−y)P, wherein 0≤x, y≤1; (x+y)≤1. When the material of the active layer 3022a, 3022b, or 3022c comprises AlGaAs or AlInGaP series material, the red light having a wavelength between 610 nm and 650 nm or the green light having a wavelength between 530 nm and 570 nm can be emitted. When the material of the active layer 3022a, 3022b, or 3022c comprises InGaN series material, the blue or the deep blue light having a wavelength between 400 nm and 490 nm or the green light having a wavelength between 490 nm and 550 nm can be emitted. When the material of the active layer 3022a, 3022b, or 3022c comprises AlGaN series or AlInGaN series material, the ultraviolet light having a wavelength between 250 nm and 400 nm can be emitted. The electrons and the holes combine in the active layers 3022a, 3022b, and 3022c under a current driving to convert the electrical energy into the light energy and then the light is emitted from the active layer 3022a, 3022b, or 3022c. The active layer 3022a, 3022b, and 3022c can be a single heterostructure (SH), a double heterostructure (DH), a double-side double heterostructure (DDH), or a multi-quantum well structure (MQW). The material of the active layers 3022a, 3022b, or 3022c can be i-type, p-type, or n-type semiconductor.
Each of the n-type semiconductor layers 3021a, 3021b, and 3021c, the p-type semiconductor layers 3023a, 3023b, and 3023c, or the active layers 3022a, 3022b, and 3022c can be a single layer or a structure comprising a plurality of layers. Although, the light emitting device 302 as depicted in
The light emitting device 402 is a p-LED device or a mini-LED device having a stack structure composed of a plurality of light-emitting elements (such as a first light-emitting element 402a, a second light-emitting element 402b, and a third light-emitting element 402c) stacked along a vertical direction (Z direction) and connected in series to form a multi-junction structure. Each of the light-emitting elements 402a, 402b, and 402c may include an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. A tunnel junction 402t1 or 402t2 may be formed between adjacent two of the light-emitting elements 402a, 402b, and 402c by means of a p-type semiconductor layer and an n-type semiconductor layer. The tunnel junction serves as an electrical connection between the adjacent two of the light-emitting elements 402a, 402b, and 402c. In some embodiments, the light emitting device 402 can be applied to the light emitting device 202 in the subpixel unit 200 as depicted in
For example, the first light-emitting element 402a includes a first n-type semiconductor layer 4021a, a first active layer 4022a, and a first p-type semiconductor layer 4023a stacked in sequence along a vertical direction (Z direction).
The second light-emitting element 402b includes a second n-type semiconductor layer 4021b, a second active layer 4022b, and a second p-type semiconductor layer 4023b stacked in sequence along a vertical direction (Z direction) on the first light-emitting element 402a.
The third light-emitting element 402c includes a third n-type semiconductor layer 4021c, a third active layer 4022c, and a third p-type semiconductor layer 4023c stacked in sequence along a vertical direction (Z direction) on the second light-emitting element 402b.
A first tunnel junction 402t1 may be formed between the first light-emitting element 402a and the second light-emitting element 402b by means of a p-type semiconductor layer and an n-type semiconductor layer. A second tunnel junction 402t2 may be formed between the second light-emitting element 402b and the third light-emitting element 402c by means of a p-type semiconductor layer and an n-type semiconductor layer.
In the present embodiment, the contact layers 414 and 419 are formed at the same side of the stack structure of the light emitting device 402. The contact layer 414 is electrically connected to the first n-type semiconductor layer 4021a of the first light-emitting element 402a and the contact layer 419 is electrically contact to the third p-type semiconductor layer 4023c of the third light-emitting element 402c.
The contact layers 414 and 419 may include Cu, W, Al, Ti, Ta, or the arbitrary combinations thereof. The tunnel junction 402t1 or 402t2 can be formed by stacking the p-type semiconductor layer and the n-type semiconductor layer through a metal-organic chemical vapor deposition (MOCVD) technology. The tunnel junctions 402t1, 402t2 include heavily doped p-type semiconductor layer and a heavily doped n-type semiconductor layer Alternatively, the tunnel junction 402t1 or 402t2 can be a layer constituted by transparent conductive material (such as ITO) formed by glue bonding or CVD technology.
In an embodiment, the light emitting device 402 comprises a substrate (not shown) comprising an insulating substrate. The substrate (not shown) can be a growth substrate for the epitaxial growth of the light-emitting elements 402a, 402b, and 402c. The substrate (not shown) comprises gallium arsenide (GaAs) wafer for epitaxially growing aluminum gallium indium phosphide (AlGaInP), or silicon (Si) wafer, sapphire (Al2O3) wafer, gallium nitride (GaN) wafer, silicon carbide (SiC) wafer, or aluminum nitride (AlN) wafer for epitaxially growing gallium nitride series materials, such as gallium nitride (GaN), indium gallium nitride (InGaN), aluminum indium gallium nitride (AlInGaN), or aluminum gallium nitride (AlGaN). The substrate (not shown) comprises a thickness within a range between 50 μm˜250 μm, between 80 μm˜200 μm in another embodiment, or between 100 μm˜150 μm in a further embodiment. In another embodiment, the light emitting device 402 does not comprises the growth substrate because the growth substrate for the epitaxial growth of the light-emitting elements 402a, 402b, and 402c is removed.
In an embodiment of the present application, the metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HYPE), physical vapor deposition (PVD), or ion plating method is performed to form the light-emitting elements 402a, 402b, and 402c with photoelectrical characteristics on the substrate (not shown), wherein the physical vapor deposition method comprises sputtering or evaporation.
The wavelength of the light emitted from the light-emitting elements 402a, 402b, and 402c is adjusted by changing the physical and chemical composition of the active layer 4022a, 4022b, or 4022c. The material of the active layer 4022a, 4022b, or 4022ccomprises III-V group semiconductor materials, such as AlGaAs or AlInGaP series material. The AlGaAs or AlInGaP series material includes AlxInyGa(1−x−y)N, AlxGa(1−x)As or AlxInyGa(1−x−y)P, wherein 0≤x, y≤1; (x+y)≤1. When the material of the active layer 4022a, 4022b, or 4022c comprises AlGaAs or AlInGaP series material, the red light having a wavelength between 610 nm and 650 nm or the green light having a wavelength between 530 nm and 570 nm can be emitted. When the material of the active layer 4022a, 4022b, or 4022c comprises InGaN series material, the blue or the deep blue light having a wavelength between 400 nm and 490 nm or the green light having a wavelength between 490 nm and 550 nm can be emitted. When the material of the active layer 4022a, 4022b, or 4022c comprises AlGaN series or AlInGaN series material, the ultraviolet light having a wavelength between 250 nm and 400 nm can be emitted. The electrons and the holes combine in the active layers 4022a, 4022b, and 4022c under a current driving to convert the electrical energy into the light energy and then the light is emitted from the active layer 4022a, 4022b, or 4022c. The active layers 4022a, 4022b, and 4022c can be a single heterostructure (SH), a double heterostructure (DH), a double-side double heterostructure (DDH), or a multi-quantum well structure (MQW). The material of the active layer 4022a, 4022b, or 4022c can be i-type, p-type, or n-type semiconductor.
Each of the n-type semiconductor layer 4021a, 4021b, and 4021c, the p-type semiconductor layer 4023a, 4023b, and 4023c, or the active layer 4022a, 4022b, and 4022c can be a single layer or a structure comprising a plurality of layers. Although the light emitting device 402 as depicted in
In addition, the first light-emitting element 402a, the second light-emitting element 402b and the third light-emitting element 402c may be subjected to a passivation treatment to form an insulating layer PSU covering there on. In an embodiment of the present application, the sidewalls of the light-emitting elements 402a, 402b, and 402c can be covered by the insulating layer PSU including SiOx or SiNx. In another embodiment of the present application, the insulating layer PSU can be a Distributed Bragg Reflector (DBR) structure that can selectively reflect light of a specific wavelength. The Distributed Bragg Reflector (DBR) can be formed by stacking layers such as SiO2/TiO2 or SiO2/Nb2O5.
The dashed black line 505 delineate the border between the linear region 506 (the left) and the saturation region 507 (the right) of the driving device 203 under different VGS. In the saturation region, the current (I) hardly changes with the drain-to-source voltages (VDS). VDD depicted in
The second thin film circuit unit 601 further includes a data line 604, a driving device 603, a switching device 607, and a capacitor 608. The driving device 603 has a terminal 603a (such as a source terminal), a terminal 603b (such as a drain terminal) and a control terminal 603c. The control terminal 603c of the driving device 603 is connected to the data line 604 through the switching device 607. The terminal 603a is connected to the power source (VDD) 606. The terminal 603b is connected to the second light emitting device 602.
The second light emitting device 602 includes a plurality of second light-emitting elements 602a, 602b, and 602c connected in series and connected to the terminal 603b of the driving device 603. One end of the capacitor 608 is connected to the power source 606 (VDD), and the other end of the capacitor 608 is connected to the control terminal 603c of the driving device 603 and the switching device 607 through a node therebetween.
In some embodiments of the present application, the first light emitting device 202 connected to the first thin film circuit unit 201 and the second light emitting device 602 connected to the second thin film circuit unit 601 emits lights with two different wavelengths. For example, in one embodiment, the first light emitting device 202 emits a blue light and the second light emitting device 602 emits a red light or a green light. In some other embodiments of the present application, the first light emitting device 202 is identical to the second light emitting device 602 such that the first light emitting device 202 and the second light emitting device 602 emit lights with substantially the same wavelength.
It should be appreciated that, although merely two thin film circuit units (the first thin film circuit unit 201 and the second thin film circuit unit 601) are depicted in
The process for forming the pixel unit 600 includes the following steps. Firstly, a plurality of mLED/μLED chips 702 is provided from a semiconductor wafer 701 to form a mLED/μLED chip array 702R. Each of the mLED/μLED chips 702 includes one of the light emitting device 302 and 402 as mentioned above. After a wafer dicing process (not shown), the separated mLED/μLED chips 702 are then transferred on and electrically connected to a TFT circuit 704 to form the pixel unit 600 as mentioned above. A device substrate 703 including integrated circuit or micro electromechanical system can be provided on the TFT circuit 704 to form a backplane 71 built in a display apparatus 70.
In an embodiment of the present application, the mLED/μLED chips 702 includes a first chip for emitting red light, a second chip for emitting green light, and a third chip for emitting blue light.
In some embodiments of the present application, each of the mLED/μLED chips 702 may emit blue light (referred to as a blue chip) or UV (referred to as a UV chip 702U). A color filter 72 is required to assemble with the backplane 71 to form the display apparatus 70 with a plurality of color pixels. In an embodiment, each pixel of the display apparatus 70 includes a UV chip 702U assembled with a blue quantum dot (QD) filter element 723, a UV chip 702U assembled with a red quantum dot (QD) filter element 721, and a UV chip 702U assembled with a green quantum dot (QD) filter element 722.
In another embodiment, each pixel of the display apparatus 70 include a blue chip assembled with a red quantum dot (QD) filter element 721, a blue chip assembled with a green quantum dot (QD) filter element 722, and a blue chip.
According to the above embodiments, the pixel unit 600 and the display apparatus 70 applying the same are provided, wherein the pixel unit 600 includes the subpixel unit including the first thin film circuit unit 201 and the first light emitting device 202 connected to the driving device 203. The plurality of light-emitting elements 202a, 202b, and 202c is connected in series to serve the first light emitting device 202, and a total voltage of the plurality of light-emitting elements 202a, 202b, and 202c is limited not less than ⅓ of a saturation voltage of the driving device 203 for turn on the first light emitting device 202. By these approach, additional device for balancing the power consumption ratio between the driving device 203 and LED (VDS/VF) may be no longer required as the amount of the light-emitting elements is increased, meanwhile the luminance of the first light emitting device 202 in the subpixel unit can also be increased when the light emitting device 202 size shrinks.
While the disclosure has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the disclosure is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
This application claims the right of priority based on U.S. Provisional Application Ser. No. 63/398,971, filed on Aug. 18, 2022, and the content of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63398971 | Aug 2022 | US |
