Light source module and backlight unit having the same

A light source module including a circuit board, a first light emitting device mounted on the circuit board by flip-chip bonding or surface mount technology (SMT), a reflective portion disposed on the circuit board and having at least one recess accommodating the first light emitting device, and a bonding member disposed between the circuit board and the reflective portion. The reflective portion has a height greater than a height of the first light emitting device.

BACKGROUND

Field

Exemplary embodiments of the present invention relate to a light source module, and more particularly, to a light source module having a low profile structure while improving an external appearance and luminous efficacy, and a backlight unit including the same.

Background

Generally backlight units are widely used for liquid crystal displays or surface lighting.

Backlight units of liquid crystal displays can be classified into direct type and edge type backlight units according to the locations of the light emitting devices.

The direct type backlight units have been mainly developed along with production of large-size liquid crystal displays having a size of 20 inches or more, and include a plurality of light sources under a diffusive plate to directly emit light towards a front side of a liquid crystal display panel. The direct type backlight units are mainly used in large-screen liquid crystal displays requiring high brightness due to their higher light use efficiency as compared to edge type backlight units.

The edge type backlight units are mainly applied to relatively small liquid crystal displays such as monitors of laptop computers and desktop computers. Such edge type backlight units have good uniformity of light illumination and a long lifespan, and advantageously permit thickness reduction of a liquid crystal display.

An edge type backlight unit structure recently proposed in the art includes a light emitting diode package that advantageously achieves low power consumption and has a low profile structure. The light emitting diode package is mounted on a substrate and disposed inside a backlight unit.

However, an edge type backlight unit including a light emitting diode package has a limit in achieving a low profile structure of the backlight unit. This is due to increased demand for further thickness reduction that makes it difficult to use highly efficient light emitting diode chips due to poor heat dissipation of the light emitting diode package.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form any part of the prior art nor what the prior art may suggest to a person of ordinary skill in the art.

SUMMARY

Exemplary embodiments of the present invention provide a light source module which is advantageous in achieving high efficiency and having a slim structure. In addition, exemplary embodiments of the present invention provide a light source module having a novel structure allowing application of a highly efficient light emitting device while achieving a slim structure.

Exemplary embodiments of the present invention further provide a technology capable of achieving a slim structure of a backlight unit while enhancing external appearance by reducing a non-display area.

An exemplary embodiment of the present invention discloses a light source module including a circuit board, a first light emitting device mounted on the circuit board by flip-chip bonding or surface mount technology (SMT), a reflective portion disposed on the circuit board and having at least one recess accommodating the first light emitting device, and a bonding member disposed between the circuit board and the reflective portion. The reflective portion has a height greater than a height of the first light emitting device.

An exemplary embodiment of the present invention also discloses a backlight unit including a light guide plate and a light source module disposed on at least one side of the light guide plate. The light source module including a circuit board, a first light emitting device mounted on the circuit board by flip-chip bonding or surface mount technology (SMT), a reflective portion disposed on the circuit board and having at least one recess accommodating the first light emitting device, and a bonding member disposed between the circuit board and the reflective portion.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of various exemplary embodiments. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects of the various illustrations may be otherwise combined, separated, interchanged, and/or rearranged without departing from the disclosed exemplary embodiments. Further, in the accompanying figures, the size and relative sizes of layers, films, panels, regions, etc., may be exaggerated for clarity and descriptive purposes. When an exemplary embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements.

FIG. 1is a sectional view of a light source module according to an aspect of the present invention.

Referring toFIG. 1, the light source module100includes a light emitting device110and a circuit board140.

The circuit board140includes substrate pads141a,141belectrically connected to the light emitting device110and bumps150a,150bplaced on the substrate pads141a,141b. The circuit board140may be a metal PCB, which is advantageous in heat dissipation, without being limited thereto. The circuit board140may be a rectangular-shaped board having a major axis and a minor axis.

The light emitting device110includes a light emitting diode chip111, a wavelength conversion layer120covering the light emitting diode chip111, and a reflective layer121covering the wavelength conversion layer120.

The light emitting diode chip111includes a growth substrate112and a semiconductor stack113. The light emitting diode chip111may be directly placed on the circuit board140by flip-chip bonding or may be electrically connected to the circuit board140by surface mount technology (SMT). Here, electrode pads37a,37bexposed on a lower surface of the light emitting diode chip111are electrically connected to the substrate pads141a,141bby the bumps150a,150b, respectively. Since the light source module100does not employ a wire, there is no need for a molding section for protection of the wire or for the partial removal of the wavelength conversion layer120to expose the bonding pads. As such, the present disclosure adopts a flip-chip type light emitting diode chip111, thereby achieving removal of color deviation or brightness spots while simplifying a process of manufacturing the light source module, as compared with a light source module adopting a light emitting diode chip using bonding wires.

The wavelength conversion layer120covers the light emitting diode chip111. The wavelength conversion layer120surrounds upper and side surfaces of the light emitting diode chip111and contains phosphors therein. The phosphors can convert wavelengths of light emitted from the light emitting diode chip111. The wavelength conversion layer120is coated onto the light emitting diode chip111and may cover the upper and side surfaces of the light emitting diode chip111in a predetermined thickness. An area of the wavelength conversion layer120covering the upper surface of the light emitting diode chip111may have the same thickness or a different thickness than the thickness of an area covering the side surfaces of the light emitting diode chip111. In addition, an area of the wavelength conversion layer120covering light exit faces through which light exits the light emitting diode chip may have a different thickness that those of the areas of the wavelength conversion layer which cover the side surfaces and the upper surface of the light emitting diode chip, excluding the light exit faces thereof.

The reflective layer121covers upper and side surfaces of the wavelength conversion layer120excluding three adjacent side surfaces of the light emitting diode chip111, which are defined as the light exit faces EA (only one of which can be seen in the cross-sectional view ofFIG. 1). The reflective layer121serves to reflect light subjected to wavelength conversion by the wavelength conversion layer120towards the light exit faces. That is, the reflective layer121guides light to exit through the three adjacent side surfaces of the light source module100. In the light emitting device110, the reflective layer121is configured to expose the three adjacent side surfaces of the wavelength conversion layer120therethrough. However, it should be understood that the present invention is not limited thereto. In other embodiments, the light emitting device110may further include a structure through which only one side of the wavelength conversion layer120is exposed.

The light source module100includes a reflective portion130formed on the circuit board140and enclosing the light emitting device110.

The reflective portion130has an accommodation recess131which accommodates the light emitting device110, and inner surfaces defined by the accommodation recess131. The accommodation recess131exposes an upper surface of the light emitting device110and the accommodation recess is open at one side thereof to provide a light discharge portion137.

The reflective portion130may be directly formed on the circuit board140by depositing and curing a molding resin on the circuit board. Alternatively, the reflective portion130may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion130serves to reflect light emitted from the light emitting device110towards the light discharge portion137and to protect the light emitting device110. The reflective portion130may have a profile, the height of which varies depending upon the design of the light emitting device110. The reflective portion130may have the same or greater height than the light emitting device110.

As described above, the light source module100includes the light emitting diode chip111mounted on the circuit board140by direct flip-chip bonding or SMT, thereby providing an advantage of realizing high efficiency and small size as compared with general package type light source modules using wires.

In addition, the light source module100is advantageous in terms of thickness reduction as compared with the general package type light source modules.

Further, in the light source module100, the reflective portion130is formed to enclose the light emitting device110on the circuit board140, thereby enabling light emitted from the light emitting device to be focused in one direction of the light source module100.

Referring toFIGS. 2aand 2b, the structure of the light emitting diode chip111will be described in more detail.

FIG. 2ais a plan view of the light emitting device shown inFIG. 1andFIG. 2bis a sectional view of the light emitting device taken along line I-I ofFIG. 2a.

Referring toFIGS. 2aand 2b, the light emitting diode chip includes the growth substrate112and the semiconductor stack113.

The semiconductor stack113includes a first conductive type semiconductor layer23formed on the growth substrate112and mesas M separated from each other on the first conductive type semiconductor layer23.

Each of the mesas M includes an active layer25and a second conductive type semiconductor layer27. The active layer25is placed between the first conductive type semiconductor layer23and the second conductive type semiconductor layer27. In addition, reflective electrodes30are placed on the M, respectively.

As shown, the mesas M may have an elongated shape extending in one direction to be parallel to each other. Such a shape of the mesas can simplify formation of the mesas M having the same shape in chip areas on the growth substrate112.

The reflective electrodes30may be respectively formed on the mesas M after the mesas M are formed, without being limited thereto. Alternatively, after the second conductive type semiconductor layer27is grown, the reflective electrodes30may be formed on the second conductive type semiconductor layer27before the mesas M are formed. The reflective electrode30covers an upper surface of the mesa M and has substantially the same shape as the shape of the mesa M in top view.

The reflective electrodes30include a reflective layer28and may further include a barrier layer29. The barrier layer29may cover an upper surface and side surfaces of the reflective layer28. For example, a pattern of the reflective layer28is formed and the barrier layer29is formed thereon, whereby the barrier layer29can be formed to cover the upper and side surfaces of the reflective layer28. For example, the reflective layer28may be formed through deposition and patterning of Ag, Ag alloy, Ni/Ag, NiZn/Ag, or TiO/Ag layers. The barrier layer29may be formed of Ni, Cr, Ti, Pt, Rd, Ru, W, Mo, TiW or combinations thereof, and prevents diffusion or contamination of metallic materials of the reflective layer.

After the mesas M are formed, an edge of the first conductive type semiconductor layer23may also be etched. As a result, an upper surface of the growth substrate112can be exposed. The first conductive type semiconductor layer23may have an inclined side surface.

According to various embodiments, the light emitting diode chip111further includes a lower insulation layer31covering the mesas M and the first conductive type semiconductor layer23. The lower insulation layer31has openings formed at predetermined locations thereof, to allow electrical connection to the first conductive type semiconductor layer23and the second conductive type semiconductor layer27therethrough. For example, the lower insulation layer31may have openings through which the first conductive type semiconductor layer23is exposed, and openings through which the reflective electrodes30are exposed.

The openings may be placed between the mesas M and near the edge of the substrate112, and may have an elongated shape extending along the mesas M. In addition, the openings are placed only above the mesas M to be biased towards the same ends of the mesas.

The light emitting diode chip111includes a current spreading layer33formed on the lower insulation layer31. The current spreading layer33covers the plurality of mesas M and the first conductive type semiconductor layer23. In addition, the current spreading layer33is placed within an upper area of each of the mesas (M) and has openings for exposing the reflective electrodes. The current spreading layer33may form an ohmic contact with the first conductive type semiconductor layer23through the openings of the lower insulation layer31. The current spreading layer33is insulated from the plurality of mesas M and the reflective electrodes30by the lower insulation layer31.

Each of the openings of the current spreading layer33has a larger area than the openings of the lower insulation layer31to prevent the current spreading layer33from being connected to the reflective electrodes30.

The current spreading layer33is formed substantially over the entirety of the upper area of the substrate112excluding the openings. This structure allows electric current to easily spread through the current spreading layer33. The current spreading layer33may include a highly reflective metal layer such as an Al layer. The highly reflective metal layer may be formed on a bonding layer such as a Ti, Cr or Ni bonding layer. In addition, a protective layer having a single layer or multilayer structure of Ni, Cr, Au, and the like may be formed on the highly reflective metal layer. The current spreading layer33may have, for example, a multilayer structure of Ti/Al/Ti/Ni/Au.

According to various embodiments, the light emitting diode chip has an upper insulation layer35formed on the current spreading layer33. The upper insulation layer35has an opening through which the current spreading layer33is exposed and openings through which the reflective electrodes30are exposed.

The upper insulation layer35may be formed of an oxide insulation layer, a nitride insulation layer, a combination layer or alternating layers of these insulation layers, or may be formed using polymers such as polyimides, Teflon, Parylene, and the like.

A first electrode pad37aand a second electrode pad37bare formed on the upper insulation layer35. The first electrode pad37ais connected to the current spreading layer33through the opening of the upper insulation layer35, and the second electrode pad37bis connected to the reflective electrodes30through the openings of the upper insulation layer35. The first and second electrode pads37a,37bmay be used as pads for connection of bumps or for SMT in order to mount the light emitting diode on the circuit board.

The first and second electrode pads37a,37bmay be formed together by the same process, for example, by photolithography and etching or by a lift-off process. The first and second electrode pads37a,37bmay include, for example, a bonding layer such as Ti, Cr or Ni, and a highly conductive metal layer such as Al, Cu, Ag or Au. Each of the first and second electrode pads37a,37bmay be formed to have both ends thereof placed on the same plane, whereby the light emitting diode chip may be flip-chip bonded to a conductive pattern, which is formed to the same height on the circuit board.

Then, the growth substrate112is divided into individual light emitting diode chip units, thereby completing fabrication of light emitting diode chips. The growth substrate112may be removed from the light emitting diode chips before or after being divided into the individual light emitting diode chip units.

As described above, the light emitting diode chip111mounted on the circuit board by direct flip-chip bonding can realize high efficiency and a small structure, as compared with a general package type light emitting device.

FIG. 3is an exploded perspective view of a display including a small backlight unit,FIG. 4is a sectional view of the display taken along line ofFIG. 3, andFIG. 5is a perspective view of a light source module ofFIG. 3.

As shown inFIG. 3toFIG. 5, the display includes a display panel (DP) on which images are displayed, a backlight unit (BLU) disposed at a rear side of the display panel (DP) and emitting light, and a light shielding tape (ST) bonding the display panel (DP) to the backlight unit (BLU) while preventing light leakage at an edge of the display.

The display panel (DP) includes a color filter substrate and a thin film transistor substrate assembled to each other to maintain a uniform cell gap therebetween while facing each other. According to type, the display panel (DP) may further include a liquid crystal layer between the color filter substrate and the thin film transistor substrate. The display panel (DP) may be provided at one side thereof with a drive interface (DI) for driving the panel.

Although not shown in detail in the drawings, the thin film transistor substrate includes a plurality of gate lines and data lines crossing each other to define pixels therebetween, and a thin film transistor placed in each of crossing areas between the gate lines and the data lines to be connected to a pixel electrode disposed in each of the pixels in one-on-one correspondence. The color filter substrate includes RGB color filters corresponding to the respective pixels, a black matrix disposed along the periphery of the substrate and shielding the gate lines, data lines and thin film transistors, and a common electrode covering all of these components. Here, the common electrode may be formed on the thin film transistor substrate.

The backlight unit (BLU) supplying light to the display panel (DP) includes a light guide plate160that converts point light into surface light, a light source module100disposed on at least one side of the light guide plate160, optical sheets150placed on the light guide plate160, and a reflective sheet170placed under the light guide plate160.

The light source module100includes a circuit board140, a light emitting device110, and a reflective portion130.

The light emitting device110is mounted on the circuit board140to be separated a constant distance from other light emitting devices. The light emitting device110emits light through three side surfaces thereof adjoining the reflective layer121(seeFIG. 1).

The reflective portion130is placed on the circuit board140and includes an accommodation recess131that accommodates the light emitting device110therein. The reflective portion130exposes an upper surface of the light emitting device110through the accommodation recess131, which has a light discharge portion137open at one side thereof. Here, the light discharge portion137corresponds to one open side of the accommodation recess131and is defined as a region through which light is discharged outside.

The accommodation recess131includes inner surfaces133,135, which adjoin the light discharge portion137and have a coplanar structure with side surfaces of the light emitting device110. That is, the inner surfaces133,135are coplanar with the corresponding side surfaces of the light emitting device110and serve to reflect light emitted from the side surfaces of the light emitting device110towards the light discharge portion137.

The reflective portion130may be directly formed on the circuit board140by depositing and curing a molding resin, without being limited thereto. Alternatively, the reflective portion130may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion130may have a profile, the height of which varies depending upon the design of the light emitting device110. The reflective portion130may have the same or greater height than the light emitting device110.

As such, the present disclosure has an advantageous effect in that light emitted from the light emitting device110is reflected towards the light guide plate160by the reflective portion130formed on the circuit board140, thereby minimizing light loss while allowing light to be focused in a desired direction.

In addition, the present disclosure can omit a separate structure such as a reflective housing for focusing light on the light guide plate160by the structure of the reflective portion130integrally formed with the circuit board140, thereby improving assembly efficiency while advantageously enabling reduction in thickness of the light source module100and a slim structure of the backlight unit (BLU) together with the light emitting device110that has a decreased thickness.

FIG. 6is a plan view of a light source module200according to an aspect of the present invention, andFIG. 7is a plan view of a light source module according to an aspect of the present invention.

Referring toFIGS. 6 and 7, light source modules200,300have the same structure as that of the light source module100except for reflective portions230,330. Thus, the similar components will be denoted by the same reference numerals and detailed descriptions thereof will be omitted.

In the light source module200, the reflective portion230is placed on a circuit board140and includes an accommodation recess231that accommodates a light emitting device110. The reflective portion230exposes an upper surface of the light emitting device110through the accommodation recess231, which has a light discharge portion237open at one side thereof. Here, the light discharge portion237corresponds to one open side of the accommodation recess231and is defined as a region through which light is discharged outside.

The accommodation recess231includes inner surfaces233,235, which adjoin the light discharge portion237and have inclined structures that are symmetrical to each other. That is, the inner surfaces233,235are configured to be gradually apart from each other in a direction of approaching the light discharge portion237. The inner surfaces233,235serve to reflect light emitted from the side surfaces of the light emitting device110towards the light discharge portion237.

The reflective portion230may be directly formed on the circuit board140by depositing and curing a molding resin, without being limited thereto. Alternatively, the reflective portion230may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion230may have a profile, the height of which varies depending upon the design of the light emitting device110. The reflective portion230may have the same or greater height than the light emitting device110.

In the light source module300, the reflective portion330is placed on the circuit board140and includes an accommodation recess331that accommodates the light emitting device110. The reflective portion330exposes an upper surface of the light emitting device110through the accommodation recess331, which has a light discharge portion337open at one side thereof. Here, the light discharge portion337corresponds to one open side of the accommodation recess331and is defined as a region through which light is discharged outside.

The accommodation recess331includes inner surfaces333,335, which adjoin the light discharge portion337and have curved structures. That is, the inner surfaces333,335are configured to be apart from each other in a direction of approaching the light discharge portion337. The inner surfaces333,335serve to reflect light emitted from the side surfaces of the light emitting device110towards the light discharge portion337.

The reflective portion330may be directly formed on the circuit board140by depositing and curing a molding resin, without being limited thereto. Alternatively, the reflective portion330may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion330may have a profile, the height of which varies depending upon the design of the light emitting device110. The reflective portion130may have the same or greater height than the light emitting device110.

FIG. 8is a perspective view of a light emitting device410according to an aspect of the present invention andFIG. 9is a plan view of a light source module500including the light emitting device ofFIG. 8.

Referring toFIGS. 8 and 9, the light source module500includes a light emitting device410, which includes at least two light emitting diode chips410a,410b.

A wavelength conversion layer420covers the at least two light emitting diode chips410a,410band a reflective layer421covers an upper surface and one side surface of the wavelength conversion layer420.

Herein, the light emitting device410is illustrated as including two light emitting diode chips410a,410b. However, it should be understood that the present invention is not limited thereto, and the number of light emitting diode chips410a,410bmay be changed.

In the light source module500, the light emitting device410including the at least two light emitting diode chips410a,410b, and a reflective portion530are placed on a circuit board140.

The reflective portion530includes an accommodation recess531that accommodates the light emitting device410therein. The reflective portion530exposes an upper surface of the light emitting device410through the accommodation recess531, which has a light discharge portion537open at one side thereof. Here, the light discharge portion537corresponds to one open side of the accommodation recess531and is defined as a region through which light is discharged outside.

The accommodation recess531includes inner surfaces533,535, which adjoin the light discharge portion537and have inclined structures. That is, the inner surfaces533,535are configured to be spaced apart from each other in a direction of approaching the light discharge portion537. The inner surfaces533,535serve to reflect light emitted from the side surfaces of the light emitting device410towards the light discharge portion537.

The reflective portion530may be directly formed on the circuit board140by depositing and curing a molding resin, without being limited thereto. Alternatively, the reflective portion530may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion530may have a profile, the height of which varies depending upon the design of the light emitting device410. The reflective portion530may have the same or greater height than the height of the light emitting device410.

In the light source module500, the reflective portion530is formed to enclose the light emitting device410on the circuit board140, thereby allowing light to be focused towards one side of the light source module500.

FIG. 10is a perspective view of a light source module600according to an aspect of the present invention andFIG. 11is a sectional view of a display including the light source module ofFIG. 10.

Referring toFIGS. 10 and 11, light source module600includes a circuit board140, a light emitting device610, a reflection cover690, and a reflective portion130.

The light source module600according to this aspect has the same structure as that of the light source module100(seeFIG. 5) except for the light emitting device610and the reflection cover690. Thus, the similar components as those of the first embodiment will be denoted by the same reference numerals and detailed descriptions thereof will be omitted.

At least one light emitting device610is mounted on the circuit board140to be separated a constant distance from other light emitting devices. The light emitting device610emits light through an upper surface and three side surfaces thereof adjoining the reflective layer621. That is, the reflective layer621is placed at one side of the light emitting device610.

The reflection cover690and the reflective portion130serve to reflect light emitted from the light emitting device610. The reflection cover690is placed on the reflective portion130. More specifically, the reflection cover690covers the reflective portion130which accommodates the light emitting device610. Namely, the reflection cover690can reflect light emitted through the upper surface of the light emitting device610.

The reflective portion130may be directly formed on the circuit board140by depositing and curing a molding resin, without being limited thereto. Alternatively, the reflective portion130may be placed on the circuit board140via a separate bonding member (not shown). The reflective portion130may have a profile, the height of which varies depending upon the design of the light emitting device610. The reflective portion130may have the same or greater height than the light emitting device610.

The display including the light source module600includes a display panel (DP) and a backlight unit (BLU).

The backlight unit (BLU) includes a light guide plate660which converts point light into surface light, a light source module600disposed on at least one side of the light guide plate660, optical sheets150placed on the light guide plate660, and a reflective sheet170placed under the light guide plate660.

The light guide plate660has a structure, one side of which adjacent the light emitting device610is thicker than a light exit area thereof. Specifically, the light guide plate660has an upper surface of a stepped structure. The stepped structure includes an inclined surface between a light incident area and the light exit area. The stepped structure of the light guide plate660is advantageous in providing a slim structure.

The light source module600is disposed on at least one side of the light guide plate660to be parallel thereto. The light source module600has a structure in which the circuit board140contacts an upper surface of the reflective sheet170.

The reflection cover690covers the reflective portion130and may extend to an upper surface of the light incident area. Although the reflection cover690is illustrated as covering the reflective portion130while extending to the upper surface of the light incident area, it should be understood that the present invention is not limited thereto and the reflection cover690may also extend to the inclined surface of the light guide plate660.

As such, the present invention has an advantageous effect in that light emitted from the light emitting device610is reflected towards the light guide plate660by the reflective portion130formed on the circuit board140and the reflection cover690placed on the reflective portion130, thereby minimizing light loss while allowing light to be focused in a desired direction.

In addition, the present invention can omit components such as a reflective housing and the like by providing a simplified structure, which includes the reflective portion130integrally formed on the circuit board140and the reflection cover690placed on the reflective portion130, thereby improving assembly efficiency while advantageously enabling reduction in thickness of the light source module and a slim structure of the backlight unit (BLU) together with the light emitting device610which has a decreased thickness.

FIG. 12is a plan view of a light source module according to an aspect of the present invention.

As shown inFIG. 12, the display has the same configuration as that of the display according toFIG. 11except for a light source module. Thus, the similar components as those ofFIG. 11will be denoted by the same reference numerals and detailed descriptions thereof will be omitted.

In the light source module, a circuit board140is directed towards a display panel (DP) and an upper surface of a reflective portion130contacts a reflective sheet170. The circuit board140is provided at one side thereof with the reflective portion130and a light emitting device610, and provided at the other side thereof with a reflection cover790.

The reflection cover790may cover the circuit board140while extending to the upper surface of the light incident area of the light guide plate660. Although the reflection cover790is illustrated as covering the circuit board140while extending to the upper surface of the light incident area, it should be understood that the present invention is not limited thereto and the reflection cover790may also extend to the inclined surface of the light guide plate660.

As such, the present invention has an advantageous effect in that light emitted from the light emitting device610is reflected towards the light guide plate660by the reflection cover790formed on the circuit board140, thereby minimizing light loss while allowing light to be focused in a desired direction.

In addition, the present invention can omit components of a typical backlight unit, such as a reflective housing and the like, by providing a simplified structure, which includes the reflective portion130integrally formed with one side of the circuit board140and the reflection cover790placed on the other side of the circuit board140, thereby improving assembly efficiency while advantageously enabling reduction in thickness of the light source module and a slim structure of the backlight unit (BLU) together with the light emitting device610which has a decreased thickness.

FIG. 13andFIG. 14are exploded perspective views of a display including a backlight unit according to an aspect of the present invention.

Referring toFIGS. 13 and 14, the display devices include the same components asFIG. 11except for a reflector890,990and a reflective sheet870. Thus, the similar components will be denoted by the same reference numerals, and detailed descriptions thereof will be omitted except for the reflector890,990.

One side surface of the light emitting device610faces a light in a light incident face of the light guide plate660. Here, the light incident face may be defined as one side surface of the light guide plate660, through which light emitted from the light emitting device610enters the light guide plate660.

The reflector890,990is disposed on the light emitting device610and the circuit board140. The reflector890,990comprises a curved structure or in an inclined structure. The reflector890,990includes one side surface to contact a portion of the upper surface of the circuit board140and the other side surface to contact a portion of the side surface of light guide plate660. That is, the first reflector may have the one side surface facing the portion of the upper surface of the circuit board140, the other side surface facing the portion of the side surface of light guide plate660. The reflector890,990may be prepared by coating a reflective material onto a surface of a base layer, or may be formed of a base layer composed of a reflective material. In addition, the reflector890,990may further include an adhesive material formed on the surface of the base layer. The reflective sheet870is disposed under the light guide plate660.

According to various embodiments, light emitted from the light emitting device610can be incident on the light guide plate660without loss due to the reflector890,990enclosing the portion of the other surface of the circuit board140and the one side surface of the light emitting device610.

Although some exemplary embodiments have been described herein, it should be understood that the present invention is not limited to certain embodiments. In addition, some features of a certain embodiment may also be applied to other embodiments in the same or similar ways without departing from the spirit and scope of the present invention as set forth in the claims.