Backlight unit and display device

Abstract

Backlighting unit for a display device (100), the backlighting unit comprising: a printed circuit (202), at least one light-emitting device (203) on the printed circuit (202), a transparent film (300) containing at least one optical pattern (310) arranged on a bottom side of the transparent film (300) facing at least one light-emitting device (203), wherein the at least one optical pattern (310) overlaps with the light-emitting device (203) and is configured to block a portion of the light emitted by the light-emitting device (203) and / or to change the angle of a portion of the light emitted by the light-emitting device (203), and at least one light output pattern (320) on a top side of the transparent film (300).wherein the part of the light with the changed angle passes through the light output pattern (320) to the display field (110) and the light output pattern (320) has a refractive index greater than the refractive index of the transparent film (300), such that the angle of refraction of the part of the light exiting the light output pattern (320) is smaller than the angle of incidence of the part of the light entering the light output pattern (320).

Description

CROSS-REFERENCE TO RELATED REGISTRATION

[0001] This application claims priority over Korean patent applications No. 10-2018-0156352, filed on December 6, 2018, and No. 10-2019-0134430, filed on October 28, 2019. BACKGROUND Area of ​​Disclosure

[0002] Embodiments of the present invention relate to a backlighting unit and a display device. Discussion of the related field

[0003] With the progress of an information-oriented society, the demands on display devices that show an image have increased, and various types of display devices, such as liquid crystal displays and organic light-emitting displays, have been widely used.

[0004] A liquid crystal display device among such display devices includes a display field and a light source device, such as a backlight unit, which supplies light to the display field.

[0005] Therefore, the thickness of the display device can increase due to the backlight unit. Conversely, if the thickness of the backlight unit is reduced, the problem arises that an insufficient optical gap between the light source and the display area is not ensured, and therefore the image quality decreases. SUMMARY

[0006] One object of the present invention is to provide a display device with improved image quality. This object is achieved by the subject matter of the independent claim. Further advantageous embodiments and refinements are described in the respective dependent claims.

[0007] According to embodiments of the present invention, a backlighting unit for a display device is provided, wherein the backlighting unit comprises: a printed circuit, at least one light-emitting device on the printed circuit, and a transparent film containing at least one optical pattern arranged on a bottom side of the transparent film and facing the at least one light-emitting device, wherein the at least one optical pattern overlaps with the light-emitting device and is configured to block a portion of the light emitted by the light-emitting device and / or to change the angle of a portion of the light emitted by the light-emitting device.

[0008] In particular, the optical pattern can be a light-changing pattern and / or can have a predetermined absorption coefficient and / or transmittance coefficient.

[0009] The backlight unit may further comprise: at least one light output pattern on a top side of the transparent film, wherein the part of the light with the modified angle passes through the light output pattern to the display field and the light output pattern has a refractive index greater than a refractive index of the transparent film, such that an angle of refraction of the part of the light exiting the light output pattern is smaller than the angle of incidence of the part of the light entering the light output pattern.

[0010] The backlighting unit may further comprise: a lacquer layer on the transparent film, wherein the lacquer layer has a refractive index lower than the refractive index of the transparent film.

[0011] The optical pattern can be configured to change the angle of a further portion of the light emitted by the light-emitting device. The lacquer layer can then reflect this further portion of the light at the modified angle to the underside of the transparent film.

[0012] The coating layer can overlap with the light output pattern.

[0013] One top surface of the coating layer can be flat.

[0014] A carrier film can be placed between the underside of the transparent film and the optical pattern. The carrier film can have a refractive index that is lower than the refractive index of the optical pattern.

[0015] The refractive index of the base film can be equal to or less than the refractive index of the transparent film.

[0016] Several optical patterns can be arranged in a grid pattern on the underside of the carrier film.

[0017] The light output pattern can have an elliptical or trapezoidal shape.

[0018] The refractive index of the optical pattern can be greater than the refractive index of the transparent film.

[0019] The thickness of a central part of the at least one optical pattern can be greater than the thickness of its peripheral part.

[0020] The backlight unit may further include a light source protection part that is arranged on the at least one light source.

[0021] The backlight unit may further comprise an adhesive layer arranged between the light source protection part and the transparent film. The adhesive layer may be arranged in at least one area that differs from an area in which the at least one optical pattern is arranged.

[0022] One edge of the at least one optical pattern may be spaced away from the adhesive layer. An air gap exists between the at least one optical pattern and the light source protection part.

[0023] The at least one optical pattern can comprise a first optical pattern located in an off-center area of ​​the backlight unit and a second optical pattern located in a central area of ​​the backlight unit. The thickness of the first optical pattern can be less than the thickness of the second optical pattern. The area of ​​the thickest part of the first optical pattern can be smaller than the area of ​​the thickest part of the second optical pattern.

[0024] The backlighting unit may further comprise a reflective film arranged in at least one area distinct from another area in which the at least one light source on the printed circuit board is located, may have a height greater than the height of the light-emitting device, and may be configured to reflect light emitted by the light-emitting device. The backlighting unit may further comprise a cover plate beneath the printed circuit board; and may further comprise adhesive tape bonding the printed circuit board to the cover plate.

[0025] A first plurality of light output patterns can be arranged in an area overlapping with several light-emitting devices, and a second plurality of light output patterns can be arranged in a further area between the multiple light-emitting devices. The first plurality of optical patterns can have a density greater than the density of the second plurality of optical patterns.

[0026] According to a further embodiment of the present invention, a display device may comprise: a display field and a backlight unit as described above.

[0027] In various embodiments of the present invention, a display device comprises a display field and a backlighting unit. The backlighting unit comprises a printed circuit, a light-emitting device on the printed circuit, and a transparent film containing a holographic film on a bottom side of the transparent film facing the printed circuit. The holographic film contains at least one optical pattern that overlaps with the light-emitting device and modifies the angle of a portion of the light emitted by the light-emitting device. The backlighting unit further comprises a light-out pattern on a top side of the transparent film, wherein the portion of the light with the modified angle passes through the light-out pattern to the display field.The light output pattern has a refractive index greater than the refractive index of the transparent film, such that the angle of refraction of the part of the light exiting the light output pattern is smaller than the angle of incidence of the part of the light entering the light output pattern.

[0028] In one embodiment, the display device further comprises a lacquer layer on the transparent film, wherein the lacquer layer has a refractive index that is lower than the refractive index of the transparent film.

[0029] In one embodiment, the optical pattern changes the angle of a further part of the light emitted by the light-emitting device, wherein the lacquer layer reflects the further part of the light at the changed angle to the underside of the transparent film.

[0030] In one embodiment, the lacquer layer overlaps the light output pattern.

[0031] In one embodiment, the part of the light passing through the light output pattern at the changed angle continues to pass through the paint layer.

[0032] In one embodiment, the top surface of the coating layer is flat.

[0033] In one embodiment, the holographic film further comprises a carrier film between the underside of the transparent film and the optical pattern, wherein the carrier film has a refractive index that is smaller than the refractive index of the optical pattern.

[0034] In one embodiment, the multiple optical patterns are arranged in a grid shape on the underside of the carrier film.

[0035] In one embodiment, the refractive index of the carrier film is equal to or less than the refractive index of the transparent film.

[0036] In one embodiment, the optical pattern is a diffraction pattern, wherein the refractive index of the optical pattern is greater than the refractive index of the transparent film.

[0037] In one embodiment, the light output pattern has an elliptical shape. A major semi-axis of the ellipse can be equal to a minor semi-axis of the ellipse. In another embodiment, a major semi-axis of the ellipse is larger than a minor semi-axis of the ellipse.

[0038] In one embodiment, the top side of the light output pattern is parallel to the bottom side of the light output pattern. The light output pattern can have a trapezoidal shape.

[0039] In one embodiment, the display device further comprises a cover base under the printed circuit and an adhesive tape that connects the printed circuit to the cover base.

[0040] In one embodiment, the holographic film contains a first plurality of optical patterns in an area overlapping with the light-emitting device and a second plurality of optical patterns in a further area overlapping with a space between light-emitting devices, wherein the first plurality of optical patterns has a density greater than the density of the second plurality of optical patterns.

[0041] In one embodiment, the display device further comprises a reflective film that receives and exposes the light-emitting device, wherein the reflective film has a height greater than the height of the light-emitting device and is configured to reflect light emitted by the light-emitting device.

[0042] In various embodiments, a backlighting unit comprises a printed circuit, a light-emitting device on the printed circuit, and a transparent film containing an optical pattern on an underside of the transparent film facing the at least one light-emitting device, wherein the optical pattern overlaps with the light-emitting device and changes an angle of a portion of the light emitted by the light-emitting device.The backlighting unit further comprises a diffusing film on the transparent film and a light output pattern on a top side of the transparent film and below the diffusing film, wherein the part of the light having the altered angle passes through the light output pattern to the diffusing film and the light output pattern has a refractive index greater than a refractive index of the transparent film, such that an angle of refraction of the part of light exiting the light output pattern is smaller than the angle of incidence of the part of light entering the light output pattern.

[0043] In one embodiment, the backlighting unit further comprises a lacquer layer between the transparent film and the diffusing film, wherein the lacquer layer has a refractive index that is smaller than the refractive index of the transparent film.

[0044] In one embodiment, the backlighting unit further comprises a color conversion film on the diffusing film and one or more optical films on the color conversion film.

[0045] In various embodiments, a backlighting unit comprises multiple light sources arranged on a printed circuit board. The backlighting unit further comprises a reflective film located in at least one area distinct from another area where the multiple light sources are arranged on the printed circuit board. The backlighting unit also includes a light source protection element located on the multiple light sources and the reflective film. Finally, the backlighting unit includes a transparent film located on the light source protection element.The backlighting unit further comprises several light-blocking patterns arranged on the underside of the transparent film at positions corresponding to the multiple light sources, with an air gap between the multiple light-blocking patterns and the light source protection part.

[0046] In one embodiment, the thickness of a central part in at least one of the several light-blocking patterns is greater than the thickness of a decentralized part.

[0047] In one embodiment, the multiple light-blocking patterns comprise a first light-blocking pattern located in a decentralized area of ​​the display field and a second light-blocking pattern located in a central area of ​​the display field, wherein a thickness of the first light-blocking pattern is less than a thickness of the second light-blocking pattern or an area of ​​the first light-blocking pattern is smaller than an area of ​​the second light-blocking pattern.

[0048] In one embodiment, the backlighting unit further comprises an adhesive layer arranged between the light source protection part and the transparent film, wherein the adhesive layer is arranged in at least one area that is distinct from another area in which the multiple light-blocking patterns are arranged, and an edge of each of the multiple light-blocking patterns is spaced away from the adhesive layer.

[0049] In the context of this disclosure, directions may be defined as follows: First, a front of the display field may be a surface of the display field from which the display field can emit light. Thus, a front of a backlight unit may point in the same direction as the front of the display field. A rear or back of the display field may be a surface of the display field opposite the front of the display field. A rear or back of the backlight unit may be defined accordingly. A frontal or vertical direction may be defined as a direction perpendicular to the front of the display field and / or the backlight unit. A horizontal direction, which includes a first and a second direction, may be defined as a direction perpendicular to the frontal direction.Accordingly, a top or upper surface can be a side or face that points in the frontal direction, and a bottom or lower surface can be defined as a side or face that points in a direction opposite to the forward direction. The width or length of an element can be defined with respect to the horizontal direction. The thickness of an element can be defined with respect to the vertical direction. List of characters Fig. Figure 1 is a diagram that schematically illustrates a configuration of a display device according to embodiments of the present invention. Fig. Figure 2 is a diagram illustrating an example of the structure of a backlight unit included in the display device according to the embodiments of the invention. Fig. 3A to Fig. 3E are diagrams that show examples of the backlight unit used in Fig. 2 is illustrated. Fig. Figure 4 is a diagram illustrating an embodiment of a backlighting unit structure according to the embodiments of the invention. Fig. 5A and Fig. 5B are diagrams that show an example of a structure through the positions of a light change pattern that is in the backlight unit that is in Fig. 4 is illustrated, is contained, illustrate. Fig. Figure 6 is a diagram illustrating an embodiment of the structure of the backlighting unit according to the embodiments of the invention. Fig. Figure 7 is a diagram showing an example of the structure of a transparent film in which diffraction patterns and light output patterns are arranged, and which is located in the backlight unit that is in Fig. 6 is illustrated, is included, is illustrated. Fig. Figure 8 is a diagram that shows another example of the structure of the transparent film, in which diffraction patterns and light output patterns are arranged, and which is located in the backlight unit that is in Fig. 6 is illustrated, is included, is illustrated. Fig. Figure 9 is a diagram that shows another example of the structure of the transparent film, in which diffraction patterns and light output patterns are arranged, and which is located in the backlight unit that is in Fig. 6 is shown, contained, illustrated. Fig. 10 is a diagram that shows an example of a structure of light output patterns found in the backlight unit located in Fig. 6 is illustrated, are included, illustrated. Fig. Figure 11 is a diagram that shows an example of an arrangement structure of light output patterns in the backlight unit that is in Fig. 6 is illustrated, are included, illustrated. Fig. Figure 12 is a diagram illustrating an example of the result of a comparison of a simulation image and a light intensity between the backlight units according to the embodiments of the invention. DETAILED DESCRIPTION

[0050] In the following, some embodiments of the present invention are described in detail with reference to the accompanying drawings. When describing the invention with reference to the accompanying drawings, the same elements are designated by the same reference numbers or numerals, regardless of the drawing numbers. If it is determined that a detailed description of known configurations or functions involved in the invention would obscure the main content of the invention, their detailed description will be omitted.

[0051] Terms such as first, second, A, B, (a) and (b) may be used to describe elements of the invention. These terms are used merely to distinguish one element from another, and the nature, order, sequence, number, or the like of the elements are not limited to these terms. When it is mentioned that an element is "linked," "coupled," or "connected" to another element, it is understood that the element may be directly coupled or connected to another element, or that yet another element may be "arranged" between them, or that the elements may be "linked," "coupled," or "connected" to one another, with yet another element arranged between them.

[0052] Fig. 1 is a diagram showing a configuration of a display device 100schematically illustrated according to embodiments of the present invention.

[0053] With reference to Fig. 1 contains the display device 100 according to the embodiments of the invention, a display field 110 , which is an active area A / A and an inactive area N / A and a gate driver circuit 120 , a data driver circuit 130 and a control unit 140 to control the display field 110 contains.

[0054] In the display field 110 are multiple gate lines GL and several data lines DL arranged and subpixels SP are located in areas where the gate lines GL and the data lines DL intersect. At least one subpixel. SP can form a pixel. The display field 110 can comprise multiple pixels, each comprising at least one subpixel.

[0055] The gate driver circuit 120 is controlled by the control unit 140 controlled and controls the targeting times of multiple subpixels SP by sequentially outputting a sampling signal to the multiple gate lines GL , which are in the display field 110 are arranged.

[0056] The gate driver circuit 120 It contains one or more integrated gate driver circuits (GDIC) and, depending on the drive mode, can be located on only one side or on both sides of the display field. 110 condition.

[0057] Each integrated gate driver circuit (GDIC) can be used in an automatic tape interconnection system (TAB system) or a chip-on-glass system (COG system) with a connecting surface of the display field. 110 can be connected or implemented in a gate-in-field system (GIP system) and displayed in the display field 110can be arranged directly. In some cases, any integrated gate driver circuit (GDIC) can be placed in the display field. 110 integrated and arranged within it. Each integrated gate driver circuit (GDIC) can be implemented in a chip-on-film (COF) system, where it is placed on a film containing the display field. 110 is connected, is mounted.

[0058] The data driver circuit 130 receives image data from the control unit 140 and converts the image data into an analog data voltage. Then the data driver circuit outputs 130 at the time when a sampling signal is sent to the gate lines GL The data voltage is applied to the data lines. DL out, such that the subpixels SP express a brightness that corresponds to the image data.

[0059] The data driver circuit 130may contain one or more integrated source driver circuits (SDICs).

[0060] Each integrated source driver circuit (SDIC) can contain a shift register, a latching circuit, a digital-to-analog converter, and an output buffer.

[0061] Each integrated source driver circuit SDIC can be used in an automatic tape interconnect system (TAB system) or a chip-on-glass system (COG system) with a connecting surface of the display field. 110 can be connected or implemented in a gate-in-field system (GIP system) and displayed in the display field 110 can be arranged directly. In some cases, the integrated source driver circuits (SDICs) can be placed in the display field. 110They can be integrated and arranged within it. Each integrated gate driver circuit (GDIC) can be implemented in a chip-on-film (COF) system. In this case, each integrated source driver circuit (SDIC) can be placed on a film containing the display field. 110 is connected, mounted and with the display panel 110 They are electrically connected via wires on the film.

[0062] The control unit 140 leads to the gate driver circuit 120 and the data driver circuit 130 It sends various control signals and controls the operation of the gate driver circuit. 120 and the data driver circuit 130 .

[0063] The control unit 140 can be mounted on a printed circuit board, a flexible printed circuit board or the like, and connected to the gate driver circuit. 120 and the data driver circuit 130electrically connected by means of the printed circuit board, the flexible printed circuit board or the like.

[0064] The control unit 140 This causes the gate driver circuit to 120 outputs a sampling signal according to a time point realized in each frame, converts image data received from outside into a data signal format that is used in the data driver circuit. 130 is used, implemented, and the implemented image data for the data driver circuit 130 spends.

[0065] The control unit 140 It receives various time signals, including a vertical synchronization signal VSYNC, a horizontal synchronization signal HSYNC, an input data activation signal DE, and a clock signal CLK, in addition to image data from outside (e.g., a host system).

[0066] The control unit 140can generate various control signals using different timing signals received from outside and send the generated control signal to the gate driver circuit 120 and for the data driver circuit 130 spend.

[0067] For example, the control unit 140 various gate control signals GCS , which contain a gate start pulse GSP, a gate switching clock GSC and a gate output activation signal GOE, for the gate driver circuit 120 spend.

[0068] Here, the gate start pulse (GSP) controls the start-up time of one or more integrated gate driver circuits (GDICs) of the gate driver circuit. 120The gate switching clock (GSC) is a clock signal that is usually input to one or more integrated gate driver circuits (GDICs) and controls the switching point of a sampled signal. The gate output activation signal (GOE) sets the timing information for the one or more integrated gate driver circuits (GDICs).

[0069] The control unit 140 It outputs various data control signals DCS, which include a source start pulse SSP, a source sample clock SSC, and a source output activation signal SOE, to control the data driver circuit. 130 to control.

[0070] Here, the source start pulse (SSP) controls the data sampling start time of one or more integrated source driver circuits (SDICs) of the data driver circuit. 130The source sampling clock (SSC) is a clock signal used to control data sampling times in one or more integrated source driver circuits (SDICs). The source output activation signal (SOE) controls an output timing of the data driver circuit. 130 .

[0071] The display device 100 It may also include an integrated power supply management circuit that is connected to the display panel. 110 , the gate driver circuit 120 , the data driver circuit 130 and the like, supplies different voltages or currents, or controls different voltages or currents to be supplied.

[0072] Each subpixel SP is through an intersection of a gate line GL and a data line DL defined and a liquid crystal or a light-emitting element can be used depending on the type of display device 100 be arranged within it.

[0073] For example, when the display device 100 A liquid crystal display device contains the display device 100 a light source device such as a backlight unit that provides light to the display field 110 emits light, and a liquid crystal is present in the subpixels. SP of the display field 110 arranged. By adjusting the orientation of the liquid crystal using an electric field generated by applying a data voltage to the subpixel. SP Once a signal is generated, it is possible to express a brightness that corresponds to image data and to display an image.

[0074] Fig. 2 is a diagram showing an example of the structure of a backlight unit used in the display device 100 illustrated according to the embodiments of the invention.

[0075] With reference to Fig. 2 contains the display device 100 according to the embodiments of the invention, a display field 110 and a backlight unit located below the display panel 110 is arranged and the display field 110 supplies light.

[0076] Different structures can be located between the backlight unit and the display panel. 110 be arranged. For example, the display field 110 using a field guide 400 , a foam cushion 500 and the like, attached to the backlighting unit, however the invention is not limited thereto.

[0077] The backlight unit can have a cover base. 201 It contains optical elements that form the backlighting unit and the like.

[0078] A printed circuit board 202 can be placed on the cover floor 201be arranged and have multiple light sources 203 can be found on the printed circuit board 202 be arranged.

[0079] The printed circuit board 202 can have a circuit board shape or a field shape and a reflective film 204 can occur in at least some areas of the region where the light sources are located. 203 on the printed circuit board 202 are not arranged, be arranged. The reflection film 204 It could be a reflective film.

[0080] A light source protection part, a light source protection film or a light source protection layer 205 can be used on multiple light sources 203 and the reflection film 204 be arranged. The light source protection part 205 can accommodate multiple light sources 203 protect and have a function of scattering light emitted by the light sources 203 Provide the emitted light. This means that the light source protection part205 can the light source 203 touch directly and the light source 203 protect and provide a function of guiding light.

[0081] A transparent film 300 is on the light source protection part 205 arranged and several optical patterns 310 can be found on the underside of the transparent film 300 and / or the top side of the transparent film 300 be arranged. The optical patterns 310 can thus the light source 203 and / or the printed circuit board 202 facing the transparent film 300 be arranged.

[0082] Here, the multiple optical patterns can be seen 310 Light control patterns. And the multiple optical patterns 310 can be arranged in positions that provide access to multiple light sources 203 on the underside of the transparent film 300correspond to them, or are opposite them, or overlap with them. That is, at least a part of each optical pattern. 310 can be arranged in such a way that it is connected to a light source 203 in a direction perpendicular to the front of the display field 110 overlapping. Alternatively, the multiple optical patterns can be used. 310 be arranged in positions that provide access to multiple light sources 203 on the top side of the transparent film 300 correspond. For example, each of the several optical patterns can 310 be arranged in such a way that it consists of holes or depressions that are in the reflective film 204 are formed, consists of, and can be used for multiple light sources. 203 correspond to or are opposite to them. In some cases, an area of ​​optical patterns may 310 like an area of ​​the hole in the reflective film 204 be. The optical patterns 310Image quality of the backlight unit can be affected by scattering, reflecting, or diffracting portions of the light emitted by the light sources. 203 vertically emitted radiation improves it. Furthermore, the optical patterns can 310 parts of the light emitted by the light source 203 is emitted, forwarded. And the optical patterns 310 These can be light control patterns that can direct portions of light.

[0083] That is, by arranging the optical patterns 310 in an area where the intensity of the light emitted by the light sources 203 When the light emitted is at its highest, it is possible to detect a luminance deviation or the like between an area where the light sources are located. 203 are arranged (an area where the light intensity is high), and an area between the light sources 203 (an area where the light intensity is low) to reduce.

[0084] A scattering film 206 , which scatters the light that enters from below, can be seen on the transparent film 300 be arranged. The scattering film 206 It could be a scattering film.

[0085] A color conversion film 207 and / or one or more optical films 208 can on the scattering film 206 be arranged.

[0086] Fig. 3A to Fig. 3E are diagrams that show examples of a specific backlight unit structure found in Fig. 2 is illustrated.

[0087] With reference to Fig. 3A are multiple light sources 203 on the printed circuit board 202 arranged.

[0088] Each light source 203 This could be, for example, a light-emitting diode (LED), a miniature light-emitting diode (mind-LED), or a micro-light-emitting diode (µLED). Accordingly, the light sources can be... 203in the form of chips on the printed circuit board 202 It can be mounted and arranged, thereby reducing the thickness of the backlight unit. Furthermore, the light source can be... 203 be of a flip-chip type.

[0089] Each light source 203 can emit light of a white wavelength band or can emit light of a specific wavelength band (e.g. a blue wavelength band).

[0090] With reference to Fig. 3B can be a reflective film 204 in at least some areas other than the areas where the light sources are located 203 on the printed circuit board 202 are arranged, be arranged.

[0091] This reflective film 204 is formed in such a way that it includes areas that are adjacent to the light sources. 203 correspond, includes those that are open, and on the printed circuit board 202It can be laid out and arranged there. The reflection film 204 reflected light from the light sources 203 The light is projected towards the front of the backlight unit to increase the backlight unit's light efficiency. In other words, the reflective film includes 204 Holes that allow light sources to pass through 203 are equivalent to.

[0092] When the light sources 203 arranged in the form of chips, the size of each light source 203 small, and therefore the height of the reflective film can be adjusted. 204 greater than the height of the light sources 203 be.

[0093] Therefore, light emitted by light sources can 203 is emitted laterally through the side surface of the reflective film. 204are reflected and radiated towards the front of the backlight unit, which can further increase the luminous efficiency of the backlight unit.

[0094] In some cases, a coated reflective film can be applied to the printed circuit board. 202 be arranged.

[0095] That is, the front (which faces the display field) 110 (facing) the printed circuit 202 or an area other than the areas where the light sources are located 203 Arranged, they can be coated with a reflective film to increase light efficiency.

[0096] In this case, the reflective film used for the printed circuit board can 202 is coated, as the reflective film 204 serve or can be used together with the reflection film 204 It may be appropriate to provide a reflection function.

[0097] With reference to Fig. 3C can be a light source protection part 205 on multiple light sources 203 and a reflection film 204 be arranged.

[0098] The light source protection part 205 It may contain, for example, a resin.

[0099] If the light source protection part 205 a resin contains the light source protection part 205 by arranging partitions outside the printed circuit board 202 or in a decentralized area of ​​the area where the multiple light sources are located 203 are arranged, and an arrangement of resin in the partition walls is formed.

[0100] The light source protection part 205 performs a function of protecting multiple light sources 203 , which are on the printed circuit board 202 are arranged, through and can serve to reflect light from the light sources. 203 is emitted, to disperse and provide a function of light guidance.

[0101] That is, the light source protection part 205 allows light emitted by the light sources to 203 The light is emitted more evenly towards the top of the light source protection part. 205 spreads.

[0102] In the embodiments of the inventions, it is possible to arrange optical patterns 310 , the optical properties at positions that are close to the light sources 203 correspond to the light source protection part 205 It is possible to reduce the thickness of the backlight unit and further improve the uniformity of an image.

[0103] With reference to Fig. 3D can be a transparent film 300 on the light source protection part 205 be arranged and contain several optical patterns 310 can be found on the underside of the transparent film 300 be arranged. And furthermore, the multiple optical patterns can 310on the top side of the transparent film 300 be arranged. The transparent film 300 can be applied to the light source protection part 205 be glued, with the adhesive layer 209 is positioned in between. The adhesive layer 209 It can be an optically transparent adhesive (OCA). The transparent film 300 It may contain, for example, PET, but embodiments of the invention are not limited to this.

[0104] The multiple optical patterns 310 , which are on the underside of the transparent film 300 are arranged, can be the multiple light sources 203 , which are on the printed circuit board 202 are arranged, correspond.

[0105] That means at least part of each optical pattern 310 can be arranged in such a way that it provides the appropriate light source 203 overlaps, and every optical pattern 310can be arranged in such a way that it overlaps an area which contains the area in which the corresponding light source is located. 203 arranged taking into account the scattering properties of light. That is, at least part of each optical pattern. 310 can be arranged in such a way that it is connected to a light source 203 in a direction perpendicular to the display field 110 overlaps.

[0106] These optical patterns 310 They possess a certain reflectivity. And optical patterns. 310 can parts of the light emitted by the light sources 203 is emitted, scattered, reflected, bent or transmitted.

[0107] For example, any optical pattern 310 Light that shines vertically (or approximately vertically) from the corresponding light source 203The light is emitted, scattered, and emitted in the vertical and oblique directions. Alternatively, the optical patterns can be... 310 allow light to reach the areas between the light sources. 203 is emitted by the light emitted from the light sources 203 when output vertically, reflect and the reflection film 204 to allow the light to be reflected again.

[0108] In this way, it is possible to adjust the direction of light emission from the light sources. 203 is emitted vertically, using the optical patterns 310 It is possible to improve the image quality of the backlight unit. This means that the luminance uniformity of the backlight unit can be improved, since light emitted from the light source 203 is emitted through the optical patterns 310The light is scattered, reflected, diffracted, or transmitted. This can improve the image quality of the display device.

[0109] With reference to Fig. 3E can be a scattering film 206 on the transparent film 300 be arranged and include a color conversion film 207 can be on the scattering film 206 be arranged. One or more optical films 208 can be done on the color conversion film 207 be arranged.

[0110] Here you can find the positions where the scattering film 206 and the color conversion film 207 are arranged, will be exchanged.

[0111] The scattering film 206 scatters light that passes through the transparent film 300 is emitted.

[0112] The color conversion film 207 It can emit light of a specific wavelength band in response to light falling upon it.

[0113] For example, the color conversion film 207 then, when the light sources 203 emit light of a first wavelength band (e.g. blue light), and in response to light incident upon them, emit light of a second wavelength band (e.g. green light) and light of a third wavelength band (e.g. red light).

[0114] The color conversion film 207 In some cases, it may only be possible in certain areas of the scattering film. 206 be arranged.

[0115] For example, the color conversion film 207 then, when the light sources 203 emit light of a blue wavelength band, only in areas outside the display area. 110 , which correspond to areas where blue subpixels SP are arranged, be arranged. That is, light that does not pass through the color-conversion film. 207 The path can be designed in such a way that it contains blue subpixels. SP of the display field 110 reached.

[0116] Depending on the light sources 203 The color conversion film must 207 not necessarily intended.

[0117] For example, the color conversion film must 207 not be provided if the light sources 203 emit light of a white wavelength band or a radiating surface of the light source 203 , which emits light of a blue wavelength band, is coated with a color conversion film that emits light of a green wavelength band and light of a red wavelength band.

[0118] In this way, in the embodiments of the invention, it is possible to enable the backlighting unit to illuminate the transparent film. 300 , which the optical patterns 310 includes those arranged at the positions corresponding to the light sources 203and various optical elements, includes reducing the thickness of the backlight unit and improving the image quality of the backlight unit.

[0119] Specific examples of optical patterns 310 , which are on the transparent film 300 The various forms and embodiments of the invention are described below.

[0120] Fig. Figure 4 is a diagram illustrating an embodiment of a backlighting unit structure according to the embodiments of the invention.

[0121] With reference to Fig. 4 is a printed circuit board 202 on a covering floor 201 arranged. The printed circuit board 202 can be done with adhesive tape 210 , which is between the cover floor 201 and the printed circuit board 202 It is arranged, it is glued.

[0122] Multiple light sources203 are on the printed circuit board 202 arranged and a reflection film 204 is present in at least some areas except those where the light sources are located. 203 are arranged.

[0123] Any light source can be used here 203 e.g., a light-emitting diode (LED) and a light-emitting part 203a , which contains an n-type semiconductor layer, an active layer and a p-type semiconductor layer, and an electrode part 203b contain.

[0124] A light source protection part, a light source protection film or a light source protection layer 205 is on the multiple light sources 203 and the reflection film 204 arranged.

[0125] A transparent film 300 , in the optical pattern 310 in positions that are close to the light sources 203 They correspond to, are arranged, is on the light source protection part 205arranged. Here the optical patterns can be 310 , which are on the underside of the transparent film 300 are arranged, light change patterns 311 be.

[0126] A scattering film 206 , a color conversion film 207 , an optical film 208 and the like can appear on the transparent film 300 be arranged.

[0127] The light change patterns 311 can be found on the underside of the transparent film 300 They can be arranged and can be achieved by printing a material that has light-blocking properties onto the transparent film. 300 to be realized and the light change patterns 311 This can be achieved, for example, by using a method for printing TiO2 ink onto the transparent film. 300 be arranged. If the light change pattern 311 TiO2 is used, then, if the light change pattern 311is arranged in a layer that determines the reflectivity of the light change pattern 311 in the range of 60 to 70%. Furthermore, the absorption / transmittance of the light change pattern can also be a factor. 311 in the range of 30 to 40%.

[0128] The light change patterns 311 , which are on the underside of the transparent film 300 They can be arranged in a single layer or in a multi-layered structure. For example, the light-changing pattern 311 be arranged in two layers. And when the light change pattern 311 When arranged in two layers, the reflectance of the light change pattern can be adjusted. 311 in the range of 70 to 80%. Furthermore, the absorption / transmittance of the light change pattern can be... 311 in the range of 20 to 30%. However, the reflectance of the light change pattern 311not limited to the examples mentioned above; if the content of TiO2, which is in the light change pattern 311 is contained, increases, or the layer thickness of the light change pattern 311 As the reflection rate of the light change pattern increases, so does the reflection rate of the light change pattern. 311 increase and the transmittance of the light change pattern 311 can lose weight.

[0129] That is, as in Fig. As illustrated in section 4, any light change pattern can be used. 311 , which is on the underside of the transparent film 300 It is arranged and contains three layers.

[0130] Such light change patterns 311 can be achieved, for example, by using a method three times to print a light-changing material onto the transparent film. 300This can be achieved, and the area or width of the light-changing material being printed can be gradually reduced. By turning the transparent film upside down. 300 , in which the light change patterns 311 are arranged, and arranging the inverted transparent film 300 on the light source protection part 205 can the light change patterns 311 on the light sources 203 be ordered.

[0131] Accordingly, the area or width of each light change pattern can be 311 downwards in the transparent film 300 decrease and the thickness of a central part of the light change pattern 311 can be greater than the thickness of its decentralized part.

[0132] This means that the intensity of the light emitted by each light source 203 When emitted vertically, the highest point can be the central part of any light change pattern. 311have a greater thickness.

[0133] In this way, it is possible to arrange the light change pattern. 311 on the light sources 203 It is possible to have light that comes from any light source. 203 vertically emitted light, to change or block it, and to prevent the occurrence of a hotspot phenomenon in the areas where the light sources are located. 203 are ordered to prevent or mitigate.

[0134] The transparent film 300 , on which the light change patterns 311 are arranged, can be arranged using an adhesive layer 209 on the light source protection part 205 be glued.

[0135] Here the adhesive layer can 209 in at least some areas of the underside of the transparent film 300 be arranged, with no light change patterns 311 on the underside of the transparent film 300 are arranged.

[0136] Accordingly, the adhesive layer 209 not located in the areas where the light change patterns 311 are arranged, and an air gap can be present between the light change patterns. 311 and the light source protection part 205 are available.

[0137] Furthermore, a side panel of each light-changing pattern can 311 and the adhesive layer 209 They can be separated from each other or spaced apart. That is, an air gap can accommodate any of the light-changing patterns. 311 surrounded in a lateral direction or a horizontal direction and in a vertical direction. That is, the air gap can be between each of the light change patterns. 311 and the adhesive layer 209 and the light source protection part 205 be arranged.

[0138] Because there is an air gap between the light change patterns 311 , the adhesive layer 209 and / or the light source protection part205 This means that light, which can be altered by any light pattern, is present. 311 The radiation emitted laterally is reflected through the air gap.

[0139] That is, light that varies from one light-changing pattern to another. 311 Light emitted laterally can be radiated at a large angle of refraction through a layer of air with a low refractive index, or it can be reflected by the air layer. The light reflected by the air layer passes through the reflective film. 204 reflected again and then emitted, and it is possible to increase the luminous efficiency, while a light-changing function or light-blocking function of the light-changing pattern 311 is supported.

[0140] In this way, it is possible to use a structure in which a light change pattern is created. 311 and an air gap at the position that each light source 203By arranging them in a way that is appropriate, it is possible to prevent a hotspot phenomenon and increase the luminous efficiency of the backlighting unit.

[0141] At this point, the light change patterns can be observed. 311 , which are on the underside of the transparent film 300 Depending on their positions, they may be arranged with different structures.

[0142] Fig. 5A and Fig. 5B are diagrams that show an example of a structure through the positions of the light change patterns in the backlight unit that is in Fig. 4 is illustrated, are included, illustrate.

[0143] Fig. Figure 5A illustrates an example of luminance shown by the backlight unit, depending on the structure of the light change patterns. 311 , where <ex1>This is an example of luminance measured when the light change patterns 311 are arranged in a constant structure, and <ex2>An example of luminance is illustrated, which is measured when the light change patterns 311 are arranged in different structures according to their positions.

[0144] As in <ex1>from Fig. As illustrated in 5A, this can then be seen when the light change patterns 311a , which are arranged in a decentralized area of ​​the backlight unit, and the light change patterns 311d , which are arranged in their central area (which is surrounded by the decentralized area), have the same structure, the luminance of the decentralized area of ​​the backlight unit will be lower.

[0145] That is, since the number of light sources 203 , which supply light to the decentralized area of ​​the backlighting unit, compared to the number of light sources 203 , which supply light to the central area, is relatively small, the luminance may be lower than that in the central area of ​​the backlight unit if the light change patterns 311 , which have the same light-changing or light-blocking properties, are arranged in both areas.

[0146] Accordingly, it is as in <ex2>from Fig. 5A illustrates this by arranging the light change patterns 311a and the light change patterns 311 d with different structures in the decentralized area and in the central area of ​​the backlighting unit, to prevent or minimize a decrease in luminance in the decentralized area of ​​the backlighting unit and to make the overall luminance more uniform.

[0147] For example, the light change patterns 311 be arranged in such a way that the thickness T1 the light change patterns 311a , which are located in the off-center area of ​​the backlight unit, less than the thickness T2 the light change patterns 311d , which are arranged in their central area.

[0148] Alternatively, the light change patterns can be 311 be arranged in such a way that the area W1 of the thickest part of the light change patterns 311b , which is located adjacent to the perimeter of the backlight unit, smaller than the area W2 of the thickest part of the light change patterns 311d This means the area of ​​the part that exhibits significant light-changing or light-blocking properties in the light-changing patterns. 311a or 311b The size of the lights located in the off-center area of ​​the backlight unit or the area adjacent to the off-center area can be set smaller.

[0149] The light change patterns 311 can be arranged in such a way that the thickness of the light change patterns 311 gradually decreases or the area of ​​the thickest part of the light change patterns 311 gradually decreasing from the central area to the decentralized area of ​​the backlight unit.

[0150] In some cases, the light change patterns can 311 be arranged differently, such that the number of light sources 203 or the gap between the light sources 203 They differ in the central area and in the peripheral area of ​​the backlight unit.

[0151] Another example of the structure in which the light change patterns 311 on the underside of the transparent film 300 are ordered, with reference to Fig. 5B described.

[0152] Here, the gap between the light sources can be... 203 , which are arranged in the perimeter area of ​​the backlight unit, smaller than the gap between the light sources 203 , which are located in the central area of ​​the backlight unit. That is to say, the light sources 203 They can be arranged more densely in the central area of ​​the backlight unit, such that the luminance in the central area and in the decentralized area of ​​the backlight unit is more uniform or constant.

[0153] Since the light change patterns 311 , which are on the underside of the transparent film 300 are arranged in such a way that they are positioned in relation to the light sources 203 The gap between the light change patterns can correspond to this. 311 , which are located in the decentralized area of ​​the backlight unit, from the gap between the light change patterns 311 , which are arranged in the central area, may be different.

[0154] For example, the gap D1 in a first direction between the light change patterns 311 , which are arranged in the off-center area between the backlight unit, smaller than the gap D2 in the first direction between the light change patterns 311 , which are arranged in the central area. The gap D3 in a second direction between the light change patterns 311 , which are located in the off-center area of ​​the backlight unit, can be smaller than the gap D4 in the second direction between the light change patterns 311 , which are located in the central area.

[0155] Here, the size, thickness, and other characteristics of the light-changing patterns can be determined. 311 , which are located in the decentralized area of ​​the backlight unit, of the size, thickness and the like of the light change patterns 311 , which are located in the central area of ​​the backlight unit, may differ.

[0156] For example, as in Fig. 5B illustrates the sizes S1 the light change patterns 311e and 311f , which are located in the off-center area of ​​the backlight unit, smaller than the size S2 the light change patterns 311g , which are located in the central area of ​​the backlight unit.

[0157] Alternatively, the light change patterns can be 311 exhibit a multilayered structure, as described above. In this case, the thickness of the light-changing patterns can vary. 311e and 311f , which are located in the off-center area of ​​the backlight unit or in the area of ​​its thickest part, smaller than the thickness of the light change patterns 311g , which are located in the central area of ​​the backlight unit or in the area of ​​its thickest part.

[0158] That is, by reducing the size of the light change patterns 311 e and 311f, which are located in the decentralized area of ​​the backlight unit, can arrange the light change patterns in such a way that they correspond to the light sources. 203 , which correspond to those arranged with a small gap. Accordingly, it is possible to observe the occurrence of a hotspot at the positions corresponding to the light sources. 203 in the decentralized area of ​​the backlight unit, to prevent or minimize.

[0159] By lowering a level, with the light emitted by the light sources 203 By changing or blocking the emitted light in the decentralized area of ​​the backlight unit, it is possible to increase the emitted light intensity, prevent or minimize a decrease in luminance in the decentralized area of ​​the backlight unit, and design the entire area of ​​the backlight unit to have a more uniform luminance.

[0160] In this way, it is possible to arrange the light change patterns. 311 Depending on the areas of the backlight unit in different structures, it is possible to prevent or minimize a decrease in luminance in the decentralized area of ​​the backlight unit and to increase luminance uniformity.

[0161] It is possible to prevent or minimize a hotspot in the backlight unit and to achieve luminance uniformity by adjusting the structures in which the light change patterns occur. 311 to be ordered to increase.

[0162] In the embodiments of the invention, it is possible to create a means that improves the image quality of the backlighting unit and the luminous efficiency by diffracting light emitted from the light sources. 203 which is radiated vertically, can increase.

[0163] Fig. Figure 6 is a diagram illustrating an embodiment of the structure of the backlighting unit according to the embodiments of the invention.

[0164] With reference to Fig. 6 is a printed circuit board 202 , which have a cover base 201 through an adhesive tape 210 is connected, arranged on that and has several light sources 203 are on the printed circuit board 202 arranged. A reflective film 204 is in at least some areas except areas where the light sources 203 are arranged on the printed circuit board 202 arranged.

[0165] A light source protection part 205 is on the multiple light sources 203 arranged and the reflection film 204 and a transparent film 300 , in the optical pattern 310 in positions that are close to the light sources 203 They correspond to, are arranged, is on the light source protection part 205 arranged.

[0166] The transparent film 300 and the light source protection part 205 can be achieved through an adhesive layer 209 be connected. A scattering film 206 , a color conversion film 207 , an optical film 208 and the like can appear on the transparent film 300 be arranged.

[0167] Here the optical patterns can be 310 , which are on the underside of the transparent film 300 are arranged, diffraction patterns 312 be. The diffraction patterns 312 can have a refractive index that is higher than the refractive index of the transparent film 300 is.

[0168] Accordingly, light emitted by any light source can 203 vertically radiated, through the corresponding diffraction pattern 312 be bent and onto the transparent film 300 incident with a large angle of refraction (e.g., a non-vertical angle of refraction).

[0169] That is, since light passing through the diffraction pattern 312 runs, onto the transparent film 300 Light falling at an angle of refraction at which total internal reflection can occur can be reflected off the transparent film. 300 falls, experience total reflection and find oneself in the transparent film 300 spread.

[0170] Multiple light output patterns 320 , which have a refractive index higher than the refractive index of the transparent film 300 is, can be seen on the transparent film 300 be arranged.

[0171] Accordingly, when light passes through the transparent film 300 Total internal reflection occurs on the underside of each light output pattern. 320 When the angle of refraction is smaller than the angle of incidence, light can pass through the light output pattern. 320 be radiated outwards.

[0172] In this way, since light from every light source 203 is projected vertically onto the transparent film 300 in a state where its optical path passes through the diffraction patterns 312 When adjusted, light loss is reduced or minimized.

[0173] Because light passing through the transparent film 300 a total internal reflection occurs from the positions where the light output patterns 320 The area or direction in which light is emitted can be determined by the arrangement of the light and the direction in which it hits the transparent film. 300 is emitted based on the positions where the light output patterns 320 are arranged, will be set.

[0174] Accordingly, it is possible to detect a loss of light from the light sources. 203 to reduce or minimize the emitted light, improve the image quality of the backlight unit, increase light efficiency by controlling the positions from which light is emitted, and reduce the power consumption of the backlight unit.

[0175] Fig. Figure 7 is a diagram that shows an example of the structure of transparent film. 300 , in the diffraction pattern 312 and light output patterns 320 are arranged and are located in the backlight unit, which is in Fig. 6 is illustrated, is included, is illustrated.

[0176] With reference to Fig. 7 are multiple diffraction patterns 312 in positions that are close to the light sources 203 correspond to the underside of the transparent film 300 arranged. Several light output patterns 320 are on the top side of the transparent film 300 arranged.

[0177] Here is a carrier film 330 between the transparent film 300 and the diffraction pattern 312 arranged. The carrier film 330 and the diffraction patterns 312 They can be collectively described as a holographic film.

[0178] That is, the diffraction patterns 312 can be found on the underside of the transparent film 300 be arranged and the carrier film 330 can be distinguished between the transparent film 300 and the diffraction patterns 312 be arranged to form an arrangement of the diffraction patterns 312 to facilitate or prevent total internal reflection of light in the transparent film 300 to improve.

[0179] The refractive index of the carrier film 330 can be lower than the refractive index of the diffraction pattern 312 Accordingly, light passing through the diffraction patterns can be 312 on the carrier film 330 incident at an angle of total reflection.

[0180] The refractive index of the carrier film 330 can be equal to or approximately close to the refractive index of the transparent film 300 This is possible if the refractive index of the carrier film is 330 from the refractive index of the transparent film 300 The different thing is to prevent excessive total reflection of light hitting the transparent film. 300 No light from the light output patterns falls upon it. 320 is emitted by ensuring that the refractive index of the transparent film is at least slightly greater than the refractive index of the base film. 330 is set.

[0181] The diffraction patterns 312 can be arranged in a form in which a specific structure is located on the underside of the carrier film. 330 The diffraction patterns are repeated and can, for example, be arranged in a lattice structure. 312 They can be arranged in various shapes that can bend light.

[0182] That is, the shape of the diffraction patterns 312 is not limited to a specific shape and light emitted by the light sources 203 is emitted and through the diffraction patterns 312 The process unfolds as revealed in the transparent film. 300 total internal reflection due to the diffraction patterns 312 and the difference between the carrier film 330 and the transparent film 300 .

[0183] Light that produces light output patterns 320 reached, which is on the transparent film 300 are arranged and have a refractive index higher than the refractive index of the transparent film 300 is determined via the light output patterns 320 radiated outwards.

[0184] For example, when light striking the transparent film at an angle of θ1 300 falls, the light output patterns 320 , which have a refractive index greater than the refractive index of the transparent film 300 Once this point is reached, the light enters at an angle of θ2, which is smaller than θ1, and can therefore reach the outside of the light output pattern. 320 be emitted.

[0185] In this way, by setting a beam path of light that falls onto the transparent film 300 comes to mind, using the light output patterns 320 It is possible to increase the light efficiency and the overall uniformity of luminance without any loss of light.

[0186] Additionally, a layer can be applied to the transparent film to improve total reflection. 300 be arranged.

[0187] Fig. Figure 8 is a diagram that provides another example of the structure of transparent film. 300 , in the diffraction pattern 312 and light output patterns 320 are arranged and are located in the backlight unit, which is in Fig. 6 is illustrated, is included, is illustrated.

[0188] With reference to Fig. 8 can be a holographic film that contains the carrier film 330 and the diffraction patterns 312 includes, in positions that are close to the light sources 203 correspond to the underside of the transparent film 300 be arranged.

[0189] The light output patterns 320 can be seen on the transparent film 300 be arranged.

[0190] A coat of paint can be applied here 340 in at least some areas except areas where the light output patterns 320 are arranged on the transparent film 300 be arranged. Some parts of the light can pass through the paint layer. 340 are refracted and further parts of the light can pass through the paint layer. 340 are reflected. The refractive index of the paint layer 340 can be smaller than the refractive index of the transparent film 300 be.

[0191] That is, if light causes total internal reflection in the transparent film 300 learns the paint layer 340 , which has a refractive index lower than the refractive index of the transparent film 300 Once reached, the light cannot reach the outside of the transparent film. 300 are emitted and therefore it is possible to achieve total internal reflection of light in the transparent film. 300 to increase.

[0192] When light causes total internal reflection in the transparent film 300 learns the light output patterns 320 Once achieved, the light can be distributed via the light output patterns. 320 be radiated outwards.

[0193] Accordingly, areas where light falls on the transparent film can 300 The amount of radiation emitted can be controlled more precisely by adjusting the paint layer. 340 and the light output patterns 320 be ordered.

[0194] The paint layer 340 can also be applied to the outer surfaces of the light output patterns 320 be ordered.

[0195] Fig. Figure 9 is a diagram that provides another example of the structure of transparent film. 300 , in the diffraction pattern 312 and light output patterns 320 are arranged and are located in the backlight unit, which is in Fig. 6 is shown, contained, illustrated.

[0196] With reference to Fig. 9. A holographic film can be used in positions that are close to the light sources. 203 correspond to the underside of the transparent film 300 be arranged and the light output patterns 320 can be seen on the transparent film 300 be arranged.

[0197] The paint layer 340 , which has a refractive index that is smaller than the refractive index of the transparent film 300 is, can be seen on the transparent film 300 be arranged and the paint layer 340 can also be found on the light output patterns 320 be arranged.

[0198] That is, since the light that falls on the light output pattern 320 If light falls at an increased angle of incidence, it can pass through the light output patterns. 320 blasted outwards, even if the paint layer 340 , which has a low refractive index, on the light output patterns 320 is arranged accordingly. 340 a function of improving the light guiding function of the transparent film 300 in areas where the light output patterns 320 are not ordered, and the protection of the light output patterns 320 carry out.

[0199] The paint layer 340 can be applied at a constant height on the transparent film 300 and the light output patterns 320 be arranged in such a way that a top surface of the paint layer 340 (above the light output patterns) 320 ) flat or parallel to the transparent film 300 is.

[0200] Accordingly, the scattering film can 206 or the like, easily on the transparent film 300 , in which the light output patterns 320 are arranged, will be arranged.

[0201] Fig. Figure 10 is a diagram that shows an example of the structure of the light output patterns. 320 , which are in the backlight unit, which are in Fig. 6 is illustrated, are included, illustrated.

[0202] With reference to Fig. 10 can display the light output patterns 320 , which are on the transparent film 300 They are arranged in various forms, taking into account the properties of the emitted light.

[0203] For example, any light output pattern 320 They have a hemispherical shape in which the horizontal and vertical radii are equal. A typical viewing angle can be determined using the light output pattern. 320 , which has a hemispherical shape in which a horizontal radius and a vertical radius are equal, can be realized.

[0204] Alternatively, any light output pattern can be used. 320 They have an elliptical shape in which one semi-major axis is larger than one semi-minor axis. For example, the semi-minor axis can be 60% of the semi-major axis. Wide viewing angle characteristics can be achieved using the light output patterns. 320 , which have an elliptical shape in which a major semi-axis is larger than a minor semi-axis, are realized.

[0205] Alternatively, any light output pattern can be used. 320 possess a shape in which one top side is flat and the top side is narrower than one bottom side. A cross-section of such a light output pattern. 320 It can have a trapezoidal shape. That is, narrow viewing angle properties can be achieved using the light output pattern. 320 , in which the top surface is flat (e.g. parallel to the bottom surface), and the front surface luminance can be increased using such a structure.

[0206] Such a structure of light output patterns 320 may depend on the characteristics of the display device 100 They can be implemented in various forms. In some cases, light output patterns can be used. 320 , which possess structures that exhibit different viewing angle properties, are mixed and arranged.

[0207] The positions, densities, and the like, with which the light output patterns are defined 320 They can be arranged depending on the positions of the light sources. 203 be determined.

[0208] Fig. 11 is a diagram that shows an example of an arrangement structure of the light output patterns 320 , which are in the backlight unit, which are in Fig. 6 is illustrated, are included, illustrated.

[0209] With reference to Fig. 11 are the diffraction patterns 312 the light sources 203 arranged accordingly or overlapping with them, and the transparent film 300 is based on the diffraction patterns 312 arranged. The light output patterns 320 are on the transparent film 300 arranged.

[0210] Here, the density with which the light output patterns are displayed can be adjusted. 320 in an area adjacent to a light source 203 (e.g. overlapping) adjacent, are arranged, smaller than the density with which they are arranged in an area adjacent to a space between (e.g. non-overlapping) the light sources. 203 adjacent, are arranged, is.

[0211] That is, the number of light output patterns 320 , which in a first area is connected to a light source 203 adjacent, arranged, can be smaller than the number of light output patterns. 320 , which is in a second area Area2, which is located in a space between the light sources 203 adjacent to and possessing the same area as the first area, are arranged.

[0212] For example, the density with which the light output patterns are 320 are arranged in the central area of ​​the backlight unit, larger than the density with which the light output patterns 320 are located in the off-center area of ​​the backlight unit. Accordingly, it is possible to prevent or minimize a reduction in the luminance of the off-center area of ​​the backlight unit, which has a relatively low light intensity (compared to the light intensity of the central area).

[0213] In this way, it is possible to adjust the positions at which the light output patterns 320 on the transparent film 300 Depending on the positions of the light sources, it is possible to arrange an optical path for the light emitted from the light sources. 203 to effectively control the emitted light and improve the luminance uniformity and image quality of the backlight unit as a whole.

[0214] Fig. Figure 12 is a diagram illustrating an example of the result of a comparison of a simulation image and luminous efficiency between the backlighting units according to the embodiments of the invention.

[0215] With reference to Fig. 12 presents CASE #1 a case in which the optical patterns 310 , which are arranged in positions that are close to the light sources 203 in the backlight unit correspond to light change patterns 311 are, and CASE #2 represents a case in which the optical patterns 310 , which are arranged in the backlight unit, diffraction pattern 312 are.

[0216] As in Fig. As shown in 12, it can be seen that by arranging the optical patterns 310 such as the light change pattern 311 or the diffraction pattern 312 at the positions that are near the light sources 203 This ensures that a hotspot is prevented and the luminance uniformity is improved.

[0217] If the diffraction patterns 312 arranged, a loss of light due to the optical patterns will occur. 310 reduced, and therefore it can be seen that the luminous efficiency is further increased.

[0218] According to the embodiments of the invention, it is possible to prevent a hotspot in the backlight unit and to ensure luminance uniformity by arranging the optical patterns. 310 , which scatter, reflect or bend light, onto the light sources 203 to increase the backlight unit.

[0219] Accordingly, it is possible to reduce the thickness of the backlight unit and provide high image quality.

[0220] By arranging the diffraction patterns 312 , which have a refractive index higher than the refractive index of the transparent film 300 is on the underside of the transparent film 300 light that passes through the diffraction patterns 312 The process is called total reflection in transparent film. 300 and therefore there is a loss of light from the light sources 203 is prevented or minimized.

[0221] By controlling a light emission path using the light output patterns 320 , which are on the transparent film 300 are arranged and have a refractive index higher than the refractive index of the transparent film 300 If this is the case, it is possible to improve the image quality of the backlight unit and increase the light efficiency in order to reduce power consumption. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] KR 1020180156352

[0001] KR 1020190134430

[0001]

Claims

[1] Backlight unit for a display device (100), the backlight unit comprising: a printed circuit (202), at least one light-emitting device (203) on the printed circuit board (202), a transparent film (300) containing at least one optical pattern (310) arranged on a bottom side of the transparent film (300) and facing at least one light-emitting device (203), wherein the at least one optical pattern (310) overlaps with the light-emitting device (203) and is configured to block part of the light emitted by the light-emitting device (203) and / or to change the angle of part of the light emitted by the light-emitting device (203). [2] Backlighting unit according to claim 1, further comprising: at least one light output pattern (320) on a top side of the transparent film (300), wherein the part of the light passes through the light output pattern (320) to the display field (110) at the modified angle and the light output pattern (320) has a refractive index greater than the refractive index of the transparent film (300) such that the angle of refraction of the part of the light exiting the light output pattern (320) is smaller than the angle of incidence of the part of the light entering the light output pattern (320). [3] Backlighting unit according to claim 2, further comprising: a lacquer layer (340) on the transparent film (300), wherein the lacquer layer (340) has a refractive index lower than the refractive index of the transparent film (300). [4] Backlighting unit according to claim 3, wherein the optical pattern (310) is configured to change the angle of a further part of the light emitted by the light-emitting device (203) and the lacquer layer (340) reflects the further part of the light at the changed angle to the underside of the transparent film (300). [5] Backlighting unit according to claim 3 or 4, wherein the lacquer layer (340) overlaps the light output pattern (320). [6] Backlighting unit according to any one of claims 3 to 5, wherein a top surface of the paint layer (340) is flat. [7] Backlighting unit according to one of the preceding claims, wherein a carrier film (330) is arranged between the underside of the transparent film (300) and the optical pattern (310) and the carrier film (330) has a refractive index that is smaller than a refractive index of the optical pattern (310). [8] Backlighting unit according to claim 7, wherein the refractive index of the carrier film (330) is equal to or less than the refractive index of the transparent film (300). [9] Backlighting unit according to claim 7 or 8, wherein several optical patterns (310) are arranged in a grid shape on a bottom side of the carrier film (330). [10] Backlighting unit according to any one of claims 2 to 9, wherein the light output pattern (320) has an elliptical shape or a trapezoidal shape. [11] Backlighting unit according to any of the preceding claims, wherein the refractive index of the optical pattern (310) is greater than the refractive index of the transparent film (300). [12] Backlighting unit according to one of the preceding claims, wherein a thickness of a central part of the at least one optical pattern (310) is greater than a thickness of its edge part. [13] Backlighting unit according to one of the preceding claims, further comprising a light source protection part (205) arranged on the at least one light source (203). [14] Backlighting unit according to claim 12, further comprising an adhesive layer (209) arranged between the light source protection part (205) and the transparent film (300), wherein the adhesive layer (209) is arranged in at least one area which is different from an area in which the at least one optical pattern (310) is arranged. [15] Backlight unit according to claim 13 or 14, wherein one edge of the at least one optical pattern (310) is spaced away from the adhesive layer (209) and / or an air gap exists between the at least one optical pattern (310) and the light source protection part (205). [16] Backlight unit according to any of the preceding claims, wherein comprising at least one optical pattern (310) comprising a first optical pattern (310) arranged in a decentralized area of ​​the backlighting unit and a second optical pattern (310) arranged in a central area of ​​the backlighting unit and a thickness of the first optical pattern (310) is smaller than a thickness of the second optical pattern (310) and / or an area of ​​the thickest part of the first optical pattern (310) is smaller than an area of ​​the thickest part of the second optical pattern (310). [17] Backlighting unit according to any of the preceding claims, further comprising: a reflective film (204) which is arranged in at least one area which is different from another area in which the at least one light source (203) is arranged on the printed circuit board (202), has a height which is greater than a height of the light-emitting device (203), and is configured to reflect light emitted by the light-emitting device (203). [18] Backlighting unit according to any of the preceding claims, further comprising: a cover base (201) under the printed circuit board (202) and an adhesive tape (210) that connects the printed circuit (202) to the cover base (201). [19] Backlighting unit according to one of the preceding claims, wherein a first plurality of light output patterns (320) is arranged in an area overlapping with several light-emitting devices (203), a second plurality of light output patterns (320) is arranged in a further area between the several light-emitting devices (203), and the first plurality of optical patterns (310) has a density greater than the density of the second plurality of optical patterns (310). [20] Display device (100) comprising the following: a display field (110) and a backlighting unit according to one of the preceding claims.