TWI819858B - Display device - Google Patents

Abstract

A display device includes a substrate, a circuit layer, a planarization layer, a first absorption layer, a light emitting unit, a wavelength selection film and a filling layer. The circuit layer is disposed on the substrate. The planarization layer is disposed between the first absorption layer and the circuit layer. The light emitting unit is disposed on the first absorption layer and is electrically connected to the circuit layer. The wavelength selection film is disposed between the first absorption layer and the light emitting unit. The filling layer is disposed on the circuit layer and covers the light emitting unit and the wavelength selection film.

Description

display device

The present invention relates to an electronic device, and in particular to a display device.

In a display device, due to the reflectivity of the substrate itself, when ambient light irradiates the substrate, a certain proportion of the ambient light will be reflected by the substrate, which causes the contrast of the display image to be reduced when viewing the display device.

One of the current solutions is to provide a circularly polarizing film on the light-emitting surface of the display device to filter out the influence of ambient light. However, this also causes the brightness of the display light to further decrease due to polarization when the display light emitted by the display device passes through the circularly polarizing film. In addition, in the current development trend of display devices, due to the gradual shrinkage of the size of light-emitting elements (such as display devices using micro-light-emitting diodes as light-emitting units), a greater proportion of light will emit light from the non-light-emitting surface of the light-emitting element (such as side) to emit light, further reducing the light emitting efficiency. How to solve the above problems is a challenge for those skilled in this field.

The present invention provides a display device with high contrast, high external quantum efficiency (External Quantum Efficiency, EQE) and high brightness.

The display device of the present invention includes a substrate, a circuit layer, a flat layer, a first absorption layer, a light emitting unit, a wavelength selective film and a filling layer. The circuit layer is disposed on the substrate, and the flat layer is disposed between the first absorption layer and the circuit layer. The light-emitting unit is disposed on the first absorption layer and electrically connected to the circuit layer. The wavelength selective film is disposed between the first absorption layer and the light emitting unit. The filling layer is arranged on the circuit layer and covers the light-emitting unit and the wavelength selective film.

Based on the above, in the display device of the present invention, the flat layer is disposed between the first absorption layer and the circuit layer. In addition to flattening the first absorption layer and the wavelength selective film on the flat layer to avoid unexpected refraction, reflection and interference to provide ideal optical properties, it can also be used to insulate the circuit layer and the light-emitting unit to avoid electrical influence on each other. On the other hand, since the wavelength-selective film is disposed between the first absorption layer and the light-emitting unit, the wavelength-selective film can selectively reflect the light beam (that is, the display light) emitted by the light-emitting unit, and allow the light beams in the remaining wavelength bands to be absorbed by the first absorbed by the layer. While having minimal impact on the display brightness, it also significantly reduces the reflection of ambient light, improves the light extraction efficiency of the display light, increases the external quantum efficiency, and improves the contrast of the display screen.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings.

10, 10A, 10B, 10C, 10D: display device

100:Substrate

110: Line layer

I20: flat layer

I30: first absorption layer

131, 131A: Second absorption layer

131AS:Side wall

131AT:Top surface

131AB: Bottom surface

140:Light-emitting unit

140T: Top surface of light emitting unit

140B: Bottom surface of light emitting unit

141: Pad

150:Wavelength selective film

150P:Pattern

151, 151’: stacked layer structure

151A: First refractive layer

151B: Second refractive layer

151C: The third refractive layer

160:Filling layer

160T: Top surface of filling layer

160B: Bottom of filling layer

170:Anti-reflective layer

A1: first area

A2: Second area

d1, d2, d3: thickness

DE: drain

G: Groove

GE: gate

H1: first height

H2: second height

IL1: first insulating layer

IL2: Second insulation layer

L1: first side length

L2: Second side length

Le: ambient light

Li, Li1, Li2: display light

M: Semiconductor layer

PE:electrode

SE: Source

TFT: switching element

X, Y, Z: direction

AA’: section line

1A is a partial cross-sectional schematic view of a display device according to the first embodiment of the present invention.

FIG. 1B is a schematic diagram of the reflectivity of the wavelength selective film of FIG. 1A to light beams of various wavelengths.

FIG. 1C is a schematic diagram of the transmittance of the wavelength selective film of FIG. 1A to light beams of various wavelengths.

FIG. 1D is a schematic cross-sectional view of each stacked layer structure of the wavelength selective film of FIG. 1A.

1E is a schematic cross-sectional view of each stacked layer structure of a modified embodiment of the wavelength selective film of FIG. 1A.

FIG. 2 is a partial cross-sectional schematic view of a display device according to the second embodiment of the present invention.

Figure 3 is a partial cross-sectional schematic view of a display device according to the third embodiment of the present invention.

4A is a partial cross-sectional schematic view of a display device according to the fourth embodiment of the present invention.

FIG. 4B is a partial top view of a display device according to the fourth embodiment of the present invention.

FIG. 5 is a partial cross-sectional schematic diagram of a display device according to the fifth embodiment of the present invention.

As used herein, "about," "approximately," "substantially," or "substantially" includes the stated value and an average within an acceptable range of deviations from a particular value as determined by one of ordinary skill in the art, taking into account that Discuss the specific quantities of measurements and errors associated with the measurements (i.e., limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or within ±30%, ±20%, ±15%, ±10%, ±5%, for example. Furthermore, the terms "approximately", "approximately", "substantially" or "substantially" used in this article can be used to select a more acceptable deviation range or standard deviation based on the measurement properties, cutting properties or other properties, and can Not one standard deviation applies to all properties.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. It will be understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or Intermediate elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical and/or electrical connections. Furthermore, "electrical connection" can be the presence of other components between the two components.

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers are used in the drawings and descriptions to refer to the same or similar parts.

1A is a partial cross-sectional schematic view of a display device according to the first embodiment of the present invention. For convenience of presentation, the number of the light-emitting units 140 may be multiple, and only one is schematically illustrated here. The present invention does not limit the number of the light-emitting units 140 .

Referring to FIG. 1A , the display device 10 includes a substrate 100 , a circuit layer 110 , a flat layer 120 , a first absorption layer 130 , a light emitting unit 140 , a wavelength selective film 150 and a filling layer 160 . The circuit layer 110 is provided on the substrate 100 , and the flat layer 120 is provided between the first absorption layer 130 and the circuit layer 110 . The light emitting unit 140 is disposed on the first absorption layer 130 and is electrically connected to the circuit layer 110 . The wavelength selective film 150 is provided between the first absorption layer 130 and the light emitting unit 140. The filling layer 160 is disposed on the circuit layer 110 and covers the light emitting unit 140 and the wavelength selective film 150 .

In this embodiment, the substrate 100 is, for example, a glass substrate or a quartz substrate, or a silicon wafer material suitable for disposing a complementary metal oxide semiconductor (Complementary Metal Oxide Semiconductor, CMOS) driving substrate. However, the present invention does not Not limited to this. In other embodiments, the substrate 100 may also be a printed circuit board (PCB).

The circuit layer 110 may include various signal lines, such as data lines, scan lines and power lines (not shown). And the circuit layer 110 may also include a first insulating layer IL1, a second insulating layer IL2, a switching element TFT, and an electrode PE, wherein the switching element TFT further includes a source electrode SE, a drain electrode DE, a semiconductor layer M, and a gate electrode GE. The first insulating layer IL1 can, for example, be used as the gate insulating layer of the gate GE, and the second insulating layer IL2 can enable the switching element TFT and the electrode PE to be disposed on opposite sides of the second insulating layer IL2. In addition, the drain electrode DE and the electrode PE can be electrically connected through the through hole between the second insulating layer IL2, so that the electrical signal transmitted by the circuit layer 110 can be transmitted sequentially through the source electrode SE, the semiconductor layer M, and the drain electrode DE. to electrode PE. The present invention is not limited thereto.

The flat layer 120 can be made of various insulating materials, such as silicon nitride (SiNx), Or other photoresist materials that are cured by ultraviolet light or heat. The flat layer 120 can not only flatten the first absorption layer 130 and the wavelength selective film 150 above it (for example, in the direction Z of FIG. 1A, that is, the normal direction of the substrate 100), so that the first absorption layer 130 and the wavelength selective film In addition to providing ideal optical properties by avoiding unexpected refraction, reflection, and interference, the selection film 150 can also be used to insulate the circuit layer 110 and the light-emitting unit 140 to prevent electrical interference from each other. The flatness of the flat layer 120 can be achieved by depositing the material forming the flat layer 120 and then flattening it through additional methods, such as chemical-mechanical planarization (CMP). The invention is not limited thereto.

The first absorption layer 130 may be a black matrix (Black Matrix, BM). Its material includes photoresist, and its light absorption value (optical density) can be greater than 1. Of course, the present invention is not limited to this. The first absorption layer 130 has high absorption rate for the entire visible light band (eg, 400 nm to 700 nm). In addition, the first absorption layer 130 may be provided with a black matrix photoresist formed by spin coating or other methods to meet this requirement. In other embodiments, other patterned absorbing layers may also be added above the first absorbing layer 130 to achieve a better effect in reducing ambient light Le reflection (described later). Therefore, the first absorbing layer 130 may also be made of materials that are suitable for being disposed in an exposure and development process, but the present invention is not limited thereto.

The light emitting unit 140 is suitable for emitting a light beam (such as the display light Li in FIG. 1A ) with at least one wavelength range, which may be a monochromatic light emitting element (such as a blue light emitting diode), and the present invention is not limited thereto. Specifically, the light-emitting unit 140 may be a white LED with a quantum dot structure (Quantum Dot, QD) or a phosphor material, which is suitable for The wavelength range of the emitted light beam may include wavelength bands of 450 nanometers (nm) to 470 nm and 510 nm to 540 nm. In some embodiments, the wavelength range of the light beam emitted by the light-emitting unit 140 further includes a first wavelength range, a second wavelength range, and a third wavelength range. The first wavelength range is, for example, between 450 nanometers (nm) and 470 nm, the second wavelength range, for example, is between 510 nm and 540 nm, and the third wavelength range, for example, is between 610 nm and 630 nm. It is worth mentioning that the first wavelength range, the second wavelength range and the third wavelength range here refer to, for example, that the half-maximum width of the main wavelength of the light beam emitted by the light-emitting unit 140 is within this range. For example, the light beam emitted by the light-emitting unit 140 includes a main wavelength of 400 nm to 500 nm, and the first wavelength range refers to the half-maximum width of the main wavelength between 450 nm and 470 nm; the light beam emitted by the light-emitting unit 140 may also include a main wavelength of 500 nm. to the main wavelength of 600nm, and the second wavelength range refers to the half-maximum width of this main wavelength between 510nm and 540nm; and the light beam emitted by the light-emitting unit 140 also includes the main wavelength between 600nm and 700nm, and the third wavelength The range refers to the half-maximum width of this main band between 610nm and 630nm. Of course, the present invention is not limited to this. In some embodiments, the light-emitting unit 140 may further include a first light-emitting element, a second light-emitting element and a third light-emitting element (not shown), wherein the first light-emitting element may be used to emit blue light in the first wavelength range. The polar body (LED) and the second light-emitting element may be a green LED for emitting a second wavelength range, and the third light-emitting element may be a red LED for emitting a third wavelength range. The present invention is not limited to this.

In addition, the light-emitting unit 140 is, for example, a micro light emitting diode (micro LED) or a sub-millimeter light emitting diode (mini light emitting diode). diode (mini LED), organic light emitting diode (organic light emitting diode (OLED)) or other sized light emitting diodes, the present invention is not limited thereto. Preferably, this embodiment uses micro light-emitting diodes. On the other hand, the light-emitting unit 140 of this embodiment is a flip-chip type light-emitting diode and has two pads 141 located on the bottom surface 140B of the light-emitting unit. For example, in this embodiment, through the pads 141 located on the same side of the light-emitting unit 140, through holes are formed on the flat layer 120, the first absorption layer 130 and the wavelength selective film 150, so that the pads 141 can communicate with the circuit layer 110 The corresponding electrodes PE are aligned with each other and bonded to each other using surface-mount technology (SMT) to achieve electrical connection between the light-emitting unit 140 and the circuit layer 110 .

In some other embodiments, the light-emitting unit 140 can also use a vertical light-emitting diode or a formal light-emitting diode, and the electrical connection between the light-emitting unit 140 and the circuit layer 110 is implemented in other ways (such as wire bonding design). The present invention is not limited thereto. The shape of the light-emitting unit 140 may be a trapezoid. For example, the angle between the bottom surface 140B of the light-emitting unit 140 and the side surface of the light-emitting unit 140 may be 110 degrees. In other embodiments, the light-emitting unit 140 may also be rectangular. In some embodiments, the top surface of the light-emitting unit 140T may also include a patterned sapphire substrate (PSS) structure to further improve the light extraction rate of the light-emitting unit 140. The present invention is not limited thereto.

The wavelength selective film 150 is adapted to selectively reflect the light beam emitted by the light emitting unit 140 (for example, the display light Li), and allows the light beam outside the display light Li wavelength band to pass through the wavelength selective film 150 and be further disposed on the wavelength selective film 150 and the flat layer 120 absorbed by the first absorbing layer 130 in between.

For example, FIG. 1B is a schematic diagram of the reflectivity of the wavelength selective film of FIG. 1A to light beams of various wavelengths, and FIG. 1C is a schematic diagram of the transmittance of the wavelength selective film of FIG. 1A to light beams of various wavelengths. Please refer to FIG. 1B and FIG. 1C at the same time. It is shown that the light Li has at least one wavelength range in the visible light band, such as the aforementioned first wavelength range (between 450nm and 470nm), or the aforementioned second wavelength range (between 510nm and 470nm). 540nm), of course, it can also be the aforementioned third wavelength range (between 610nm and 630nm), or a combination of the first wavelength range, the second wavelength range, and the third wavelength range. The wavelength selective film 150 has a first reflectivity and a first transmittance for the light beam within the above wavelength range, and has a second reflectivity and a second transmittance for the light beam falling outside the above wavelength range, wherein the first reflectance is greater than The second reflectivity and the first transmittance are smaller than the second transmittance.

Specifically, as can be seen from FIG. 1B , since the wavelength segment of the display light Li emitted by the light-emitting unit 140 falls within the above-mentioned first wavelength range, the second wavelength range, and the third wavelength range, the wavelength selective film 150 is sensitive to the wavelength range within the above-mentioned wavelength range. The first reflectivity of the light beam is, for example, 99%, and the second reflectivity of the light beam falling outside the above wavelength range is, for example, 1%. Therefore, the wavelength selective film 150 has extremely high reflectivity for the wavelength band of the display light Li, allowing the display light Li to be reflected by the wavelength selective film 150 and then transmitted to the user with minimal energy loss, thereby increasing the light output of the light-emitting unit 140 efficiency and external quantum efficiency, so that the display screen has sufficient brightness.

Following the above, it can be seen from FIG. 1C that since most of the wavelength bands of the ambient light Le fall outside the first wavelength range, the second wavelength range, and the third wavelength range, the wavelength selective film 150 does not detect light beams within the above wavelength ranges. The first transmittance is, for example, 1%, and the second transmittance for light beams falling outside the above wavelength range is, for example, 99%. therefore, The display light Li will hardly penetrate the wavelength selective film 150 , while most of the light beams in the ambient light Le will pass through the wavelength selective film 150 and illuminate below the wavelength selective film 150 (for example, the opposite direction of the direction Z in FIG. 1A ) of the first absorption layer 130 and is further absorbed by the first absorption layer 130 . Therefore, most of the ambient light Le cannot be reflected to the user, so that glare interference caused by reflection of the ambient light Le can be reduced. And since almost all of the display light Li is reflected by the wavelength selective film 150, the display screen of the display device 10 can still achieve good contrast even in an environment where the ambient light Le is too bright.

FIG. 1D is a schematic cross-sectional view of each stacked layer structure of the wavelength selective film of FIG. 1A. Referring to FIG. 1D , the aforementioned wavelength selective film 150 can be implemented through the following method. Specifically, the wavelength selective film 150 may further include a plurality of stacked layer structures 151, and each stacked layer structure 151 includes a first refractive layer 151A and a second refractive layer 151B, wherein the first refractive layer 151A has a first refractive index. , the second refractive layer 151B has a second refractive index, and the first refractive index and the second refractive index are different.

Specifically, the thickness d1 of the first refractive layer 151A and the thickness d2 of the second refractive layer 151B may be between 10 nanometers and 300 nanometers. The first refractive layer 151A and the second refractive layer 151B can be made of dielectric materials commonly used in the semiconductor field such as silicon nitride (SiN _x ), silicon oxide (SiO _x ) or titanium dioxide (TiO ₂ ). The absolute value of the difference between the first refractive index and the second refractive index may be greater than 0.3. The first refractive layer 151A and the second refractive layer 151B can be arranged by depositing and forming the first absorption layer 130 and then sequentially and alternately depositing the materials of the first refractive layer 151A and the second refractive layer 151B to complete each stacked layer. The stacking of the structures 151 (that is, the arrangement of the wavelength selective film 150 is completed). For convenience of presentation, FIG. 1D only schematically depicts a pair of stacked layer structures 151 . Of course, the number of stacked layer structures 151 may be multiple, and the present invention does not limit the number of stacked layer structures 151 .

In some embodiments, in order to further optimize the wavelength selection effect of the wavelength selective film 150, the absolute value of the difference between the first refractive index of the first refractive layer 151A located in the outermost layer of the wavelength selective film 150 and the refractive index of the filling layer 160 , which can be between 0 and 1. In some embodiments, the outermost layer of the wavelength selective film 150 may also be the second refractive layer 151B, and the absolute value of the difference between the second refractive index of the second refractive layer 151B and the refractive index of the filling layer 160 may be Between 0 and 1.

1E is a schematic cross-sectional view of each stacked layer structure of a modified embodiment of the wavelength selective film of FIG. 1A. Referring to FIG. 1E , the aforementioned wavelength selective film 150 can also be implemented through the following method. Specifically, the wavelength selective film 150 may further include a plurality of stacked layer structures 151', and each stacked layer structure 151' respectively includes a first refractive layer 151A, a second refractive layer 151B and a third refractive layer 151C, wherein the first The refractive layer 151A has a first refractive index n1, the second refractive layer 151B has a second refractive index, and the third refractive layer 151C has a third refractive index. The first refractive index, the second refractive index, and the third refractive index are all different. The properties, formation methods and material selection of the first refractive layer 151A, the second refractive layer 151B and the third refractive layer 151C can be referred to the above and will not be described again here.

Please refer to Figure 1A. On the other hand, the filling layer 160 can be used to fix, isolate and protect the light-emitting unit 140 to prevent the light-emitting unit 140 from being oxidized or corroded by moisture and oxygen, and the filling layer 160 can provide adequate protection when the display device 10 is subjected to external force. Decent buffering. Therefore, the filling layer 160 is preferably selected from a material with stable and insulating properties. In addition, the filling layer 160 is also beneficial to the flattening of the entire display device 10 . On the other hand, the optical properties of the filling layer 160 are preferably materials with high transmittance to prevent the filling layer 160 from affecting the light extraction efficiency of the light emitting unit 140 . In some embodiments, optical clear adhesive (Optical Clear Adhesive, OCA), optical clear resin (Optical Clear Resin, OCR), or other suitable optical grade adhesive materials and a glass cover (not shown) may be further disposed on the filling layer 160. (shown) to further enhance the protection effect of the display device 10.

Other embodiments will be enumerated below to describe the present invention in detail, in which the same components will be marked with the same symbols, and descriptions of the same technical content will be omitted. Please refer to the previous embodiments for the omitted parts, which will not be described again.

FIG. 2 is a partial cross-sectional schematic view of a display device according to the second embodiment of the present invention. Please refer to FIG. 2 . The display device 10A of this embodiment is similar to the display device 10 of FIG. 1A . The difference lies in that an anti-reflective layer 170 is further provided on the top surface 160T of the filling layer. The filling layer 160 is positioned between the light emitting unit 140 and the anti-reflective layer 170 .

The anti-reflective layer 170 is formed, for example, by performing plasma surface treatment on the top surface 160T of the filling layer. Of course, another anti-reflective material may also be provided to form the anti-reflective layer 170. The present invention is not limited thereto. The anti-reflective layer 170 can reduce the reflection of the ambient light Le between the external medium (such as air) and the filling layer 160 to further reduce the glare problem caused by the ambient light Le. And as mentioned above, when the ambient light Le from the outside penetrates into the interior of the display device 10A, it can then pass through the wavelength selective film. The interaction between 150 and the first absorbing layer 130 further suppresses the reflection of ambient light Le on the display device 10A.

Figure 3 is a partial cross-sectional schematic view of a display device according to the third embodiment of the present invention. Please refer to Figure 3. The display device 10B of this embodiment is similar to the display device 10A of Figure 2. The difference is that the display device 10B further includes a second absorption layer 131, which is disposed on the wavelength selective film 150, and the second absorption layer 131 is provided around the light emitting unit 140.

Specifically, the second absorption layer 131 is disposed around the light-emitting unit 140 in the plane direction of the substrate 100 (for example, the XY plane composed of the direction X and the direction Y in FIG. 3 ) without overlapping the light-emitting unit 140 . To put it another way, when viewed from a top view of the substrate 100 (for example, viewed through the reverse direction Z in FIG. 3 ), the light-emitting unit 140 is surrounded by the second absorption layer 131 .

The second absorption layer 131 also has high absorption rate for the entire visible light band. Therefore, the second absorption layer 131 can be formed of the same material as the first absorption layer 130 by spin coating or depositing on the wavelength selective film 150 and then using a patterning process (such as lithography, etching, etc.). After the patterning process of the second absorption layer 131 is completed, through holes are formed on the flat layer 120, the first absorption layer 130 and the wavelength selective film 150, so that the light-emitting unit 140 can pass through the electrode PE and the circuit via the pad 141. Layer 110 is electrically connected. Of course, the present invention is not limited to this.

Through the above design, when the display light Li2 emitted by the light-emitting unit 140 has an excessive light emission angle, it can be absorbed by the second absorption layer 131 around the light-emitting unit 140 . The display light Li1 with a smaller light emission angle can be reflected by the wavelength selective film 150. The light beam emitted by the light-emitting unit 140 is effectively emitted toward the front (for example, direction Z in FIG. 3 ), thereby avoiding the crosstalk problem that may be caused by the light-emitting unit 140 being too close to other light-emitting units (not shown). Similarly, because the second absorption layer 131 has a high absorption rate for the entire visible light band. It can effectively absorb all the bands of ambient light Le, thus further reducing the impact of ambient light Le on the display screen, and also effectively improving the contrast of the display screen.

4A is a partial cross-sectional schematic view of a display device according to the fourth embodiment of the present invention. FIG. 4B is a partial top view of a display device according to the fourth embodiment of the present invention. The partial cross-sectional view of Figure 4A is drawn along the section line AA' in Figure 4B. Please refer to FIGS. 4A and 4B at the same time. The display device 10C of this embodiment is similar to the display device 10A of FIG. 2 . The difference lies in that the wavelength selective film 150 of the display device 10B is separated into a plurality of patterns 150P, and the light-emitting unit 140 includes A plurality of light-emitting elements 140. The light-emitting elements 140 are correspondingly arranged on the patterns 150P, and the filling layer 160 located between the patterns 150P contacts the first absorption layer 130 . Any pattern 150P has a first area A1, any light emitting element 140 has a second area A2, and the first area A1 is larger than the second area A2.

Specifically, the pattern 150P of the display device 10C is further formed by a patterning process through the wavelength selective film 150 as mentioned above. This allows the filling layer 160 to be located between adjacent patterns 150P (that is, in the direction X and direction Y, the filling layer 160 is located between adjacent patterns 150P), and the bottom surface 160B of the filling layer contacts the first absorbing layer 130 . The so-called first area A1 refers to the projected area of any pattern 150P in the normal direction of the substrate 100 (for example, the direction Z in FIG. 4B). Similarly, the so-called second The area A2 refers to the projected area of any light-emitting element 140 in the normal direction of the substrate 100 (for example, the direction Z in FIG. 4B ). The first side length L1 of the first area A1 (that is, the width of the pattern 150P) is, for example, 25 microns (μm), and the second side length L2 (that is, the length of the pattern 150P) is, for example, 40 μm. The width of the light-emitting unit 140 may be 15 μm, and the length may be, for example, 30 μm. Of course, the present invention is not limited to this. As long as the first area A1 of any pattern 150P is larger than the second area A2 of any light emitting element 140, and the second area A2 completely overlaps the first area A1.

Through the above design, each light-emitting element 140 can be surrounded by the first absorption layer 130 when viewed from a top view of the display device 10C. The large-angle display light (for example, display light Li2) emitted by the light-emitting unit 140 can be absorbed by the first absorption layer 130 around the light-emitting unit 140. Since the first area A1 is larger than the second area A2 and the second area A2 completely overlaps the first area A1, the display light Li1 with a smaller light emission angle emitted by the light-emitting element 140 can be captured by the pattern 150P of the wavelength selective film 150. reflection. Then, the light beam emitted by the light-emitting unit 140 is effectively emitted toward the front (for example, direction Z in FIG. 3 ). Likewise, since the first absorption layer 130 has a high absorption rate for the entire visible light band. It can effectively absorb all the bands of ambient light Le, thus further reducing the impact of ambient light Le on the display screen, and also effectively improving the contrast of the display screen. In other words, even if the display device 10C of this embodiment is not further provided with the patterned second absorption layer 131, it can still achieve similar effects to the aforementioned display device 10B.

FIG. 5 is a partial cross-sectional schematic diagram of a display device according to the fifth embodiment of the present invention. Please refer to Figure 5. The display device 10D of this embodiment is the same as the display device of Figure 2. The display device 10A is similar to the display device 10A, but the difference is that the second absorption layer 131A of the display device 10D is disposed on the first absorption layer 130 and contacts a part of the first absorption layer 130, and the second absorption layer 131A surrounds the light-emitting unit 140 to form Groove G, the wavelength selective film 150 covers the first absorption layer 130 and the sidewall 131AS of the groove G, the second absorption layer 131A has a first height H1 in the normal direction of the substrate 100 (for example, the Z direction in FIG. 5), The light emitting unit 140 has a second height H2 in the normal direction of the substrate, and the first height H1 is greater than or equal to the second height H2.

The first height H1 here may refer to the vertical distance from the top surface 131AT of the second absorption layer 131A to the bottom surface 131AB of the second absorption layer 131A. The second height H2 may refer to the vertical distance from the top surface 140T of the light-emitting unit 140 to the bottom surface 131AB of the second absorption layer 131A. In other words, the light-emitting unit 140 of this embodiment is further located in the groove G formed by the second absorption layer 131A. Here, the first height H1 of the second absorption layer 131A in FIG. 5 is shown to be greater than the second height H2 of the light emitting unit 140 . In other embodiments, the first height H1 of the second absorption layer 131A may also be equal to the second height H2 of the light-emitting unit 140 . The present invention is not limited thereto.

The second absorption layer 131A may be made of the same material as the first absorption layer 130 . In addition, the second absorption layer 131A may be formed by using a similar method to form the second absorption layer 131A to a predetermined first height H1 after the first absorption layer 130 is formed by the aforementioned spin coating method or deposition method. And cooperate with the exposure and development process or the etching process to form the groove G as shown in Figure 5. Next, after the deposition of the wavelength selective film 150 is completed, through holes are formed in the flat layer 120, the first absorbing layer 130 and the wavelength selective film 150 located at the bottom projection of the groove G to complete the transposition of the light emitting unit 140 and realize the emission. Electrical connection between the optical unit 140 and the circuit layer 110 . For relevant methods, please refer to the previous paragraphs and will not be repeated here.

Through the above design, since the wavelength selective film 150 covers the sidewall 131AS of the groove G, the light emitted from the light emitting unit 140 at a large angle (such as the display light Li) can also be forward reflected by the wavelength selective film 150 with almost no energy loss. to the user, so as to facilitate the light emitting unit 140 to emit light in the forward direction. As mentioned above, most of the wavelength bands of the ambient light Le will pass through the wavelength selective film 150 and be absorbed by the first absorption layer 130 below the wavelength selective film 150 . In addition, the top surface 131AT of the second absorption layer 131A may not be covered by the wavelength selective film 150, so the ambient light Le irradiating the top surface 131AT may be absorbed by the second absorption layer 131A to further reduce the influence of the ambient light Le. The contrast of the display device 10D is increased.

To sum up, in the display device of the present invention, the flat layer is disposed between the first absorption layer and the circuit layer. In addition to flattening the first absorption layer and the wavelength selective film on the flat layer to avoid unexpected refraction, reflection and interference to provide ideal optical properties, it can also be used to insulate the circuit layer and the light-emitting unit to avoid electrical influence on each other. On the other hand, since the wavelength-selective film is disposed between the first absorption layer and the light-emitting unit, the wavelength-selective film can selectively reflect the light beam (that is, the display light) emitted by the light-emitting unit, and allow the light beams in the remaining wavelength bands to be absorbed by the first absorbed by the layer. While having minimal impact on display brightness, it also significantly reduces ambient light reflection, improves the light extraction efficiency of display light, increases external quantum efficiency, and improves the contrast of the display screen.

Although the present invention has been disclosed above through embodiments, it is not intended to limit the scope of the present invention. Any person with ordinary knowledge in the technical field may make slight changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of protection of the invention shall be deemed to be defined by the appended patent application scope. Accurate.

10:Display device

100:Substrate

110: Line layer

120:Flat layer

130: First absorption layer

140:Light-emitting unit

140T: Top surface of light emitting unit

140B: Bottom surface of light emitting unit

141: Pad

150:Wavelength selective film

160:Filling layer

DE: drain

GE: gate

IL1: first insulating layer

IL2: Second insulation layer

Le: ambient light

Li: display light

M: Semiconductor layer

PE:electrode

SE: Source

TFT: switching element

X, Y, Z: direction

Claims (12)

A display device, including: a substrate; a circuit layer provided on the substrate; a flat layer provided on the circuit layer; a first absorption layer provided on the flat layer, wherein the flat layer is provided on the first absorption layer and the circuit layer; a light-emitting unit, disposed on the first absorption layer and electrically connected to the circuit layer; a wavelength selective film, disposed between the first absorption layer and the light-emitting unit; a filling layer, disposed on the circuit layer and covering the light-emitting unit and the wavelength selective film. The display device of claim 1, wherein the light beam emitted by the light-emitting unit has at least one wavelength range in the visible light band, and the wavelength selective film has a first reflectivity and a first transmittance for the light beam in at least one wavelength range. , the light beam outside the at least one wavelength range has a second reflectivity and a second transmittance, the first reflectivity is greater than the second reflectivity, the first transmittance is less than the second transmittance, wherein the The first absorbing layer is adapted to absorb the light beam in the visible light band. The display device of claim 2, wherein the at least one wavelength range further includes a first wavelength range, a second wavelength range, and a third wavelength range. The display device of claim 2, wherein the light-emitting unit further includes a first light-emitting element, a second light-emitting element, and a third light-emitting element, and the at least one wavelength range further includes a first wavelength range, a second wavelength range, and a third light-emitting element. Wavelength range range, wherein the first light-emitting element is suitable for emitting a beam of light in the first wavelength range, the second light-emitting element is suitable for emitting a light beam of the second wavelength range, and the third light-emitting element is suitable for emitting a light beam of the third wavelength range. . The display device of claim 1, wherein the wavelength selective film further includes: a plurality of stacked layer structures, wherein each of the stacked layer structures includes a first refractive layer and a second refractive layer, wherein The first refractive layer has a first refractive index, the second refractive layer has a second refractive index, and the first refractive index and the second refractive index are different. The display device of claim 5, wherein the thickness of the first refractive layer and the thickness of the second refractive layer are between 10 nanometers and 300 nanometers. The display device of claim 5, wherein the absolute value of the difference between the first refractive index and the second refractive index is greater than 0.3. The display device of claim 5, wherein the absolute value of the difference between the first refractive index of the first refractive layer located in the outermost layer of the wavelength selective film and the refractive index of the filling layer is between 0 and between 1. The display device of claim 5, wherein the absolute value of the difference between the second refractive index of the second refractive layer located in the outermost layer of the wavelength selective film and the refractive index of the filling layer is between 0 and between 1. The display device according to claim 1, further comprising: a second absorption layer disposed on the wavelength selective film, and the second absorption layer is disposed around the light-emitting unit. The display device of claim 1, wherein the wavelength selective film is separated into a plurality of patterns, the light-emitting unit includes a plurality of light-emitting elements, the light-emitting elements are correspondingly arranged on the patterns, and the light-emitting elements between the patterns The filling layer contacts the first absorption layer, any one of the patterns has a first area, any one of the light-emitting elements has a second area, and the first area is larger than the second area. The display device of claim 1, further comprising: a second absorption layer disposed on the first absorption layer and contacting a portion of the first absorption layer, the second absorption layer surrounding the light-emitting unit to form a Groove, the wavelength selective film covers the first absorption layer and the sidewall of the groove, the second absorption layer has a first height in the normal direction of the substrate, and the light-emitting unit has a height in the normal direction of the substrate The second height, the first height is greater than or equal to the second height.

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