Patent ID: 12197071

DESCRIPTION OF SPECIFIC EMBODIMENTS

Configuration and operation according to the present invention are described hereafter in detail with reference to the accompanying drawings. In the following description referring to the accompanying drawings, the same components are given the same reference numerals in the figures and the description is not provided. The terms, ‘first’ and ‘second’ etc., can be used to describe various components, but the components are not limited to the terms. Terms described in the specification is used to discriminate one component from other components.

The present invention has been designed to improve reflectivity and luminance by disposing a reflecting unit having a spaced area under an LED in a lighting apparatus using the LED as a light source. In particular, in the structure of a lighting apparatus of the related art, the present invention provides a structure that makes it possible to improve optical properties by an optical pattern layer for implementing a spaced area by patterning a bonding material (bonding pattern layer) or a spaced module having a spaced layer by patterning a diffusion member or using a specific member, and particularly, to greatly reduce the entire thickness of the lighting apparatus by removing a light guide plate and forming a resin layer instead of the light guide plate and to reduce the number of light sources.

Further, the lighting apparatus according to the present invention is not limited to a backlighting apparatus of the liquid crystal display described above. That is, the present invention can be obviously applied to various lamps that require lighting, such as lamps for vehicles, home lighting devices, and industrial lighting devices. The lamps for vehicles are obviously the headlight, interior and exterior lamps, and rear light.

1. 1. First Embodiment

FIG.3is a conceptual cross-sectional view showing the main parts of a lighting apparatus according to the present invention.

Referring toFIG.3, a lighting apparatus according to the present invention includes a plurality of LEDs130disposed on a printed circuit board110and a reflecting unit120stacked on the printed circuit board110, with the LEDs130through it, on the printed circuit board110. In particular, a spaced area A1is defined inside the reflecting unit120in this configuration. The spaced area A1can maximize luminance by increasing the reflective efficiency of light out of the light sources130.

In particular, the reflecting unit120may include a first reflective member121attached to the surface of the printed circuit board110and a second reflective member122made of a transparent material for forming the spaced area A1and spaced apart from the first reflective member121. The first and second reflective members121and122are stacked on the printed circuit board and the LEDs130protrude outward through holes formed through the reflective members.

The spaced area A1makes it possible to form the first and second reflective members121and122in an integral pressed structure without using a specific adhesive, and as shown in the figure, the first and second reflective members121and122may be spaced apart from each other to define the spaced area A1filled with air, by a spaced member123such as a specific bonding member.

In this structure, the first reflective member121may be a film with a reflective material that reflects light, such as a metal layer made of Ag and the second reflective member122is preferably a film made of a transparent material such that the light from the LEDs travels and reflects again from the surface of the first reflective member122. In particular, the first reflective member121is a reflective structure that reflects light, and particularly, the first reflective member121is preferably made of white PET (white polyethylene terephthalate) in the present invention. That is, the first reflective member may be implemented by a common metal reflective material layer (Ag etc.) in the specific reflective unit according to the present invention, but white PET (white polyethylene terephthalate) may be used to maximally improve the luminance. It is possible to improve the luminance by about 30% in comparison to the related art, when the first reflective member is made of white PET (white polyethylene terephthalate) to implement the reflecting unit.

In particular, it is further preferable to provide a reflective pattern124by printing white on the surface of the second reflective member122such that the luminance can be improved by further diffusing light, in addition to allowing the light emitted from the light sources130to reflect again from the second reflective member after passing through the first reflective member. A reflective pattern130is provided to greatly improve reflectivity of light and may be printed with reflective ink containing any one of TiO2, CaCO3, BaSO4, Al2O3, Silicon, and PS.

In particular, various light sources may be used for the light sources of the lighting apparatus according to the present invention, and preferably, side emission type of LEDs may be used, in which the reflective pattern is preferable formed in the emission direction of the LEDs and particularly, it may be disposed such that the pattern density increases with the increase in distance from the LEDs in the emission direction. Using the side emission type of LEDs makes it possible to considerably reduce the number of light sources.

FIG.4is a view showing an example of a spaced member of a reflecting unit included in the lighting apparatus of the present invention shown inFIG.3.

That is, the spaced member according to the present invention may be a common member that defines an spaced area by spacing the first reflective member and the second reflective member, such as a spacer that simply spacing them or an adhesive spacer, but preferably, the spaced member may be formed by uniformly or randomly patterning a structure patterned in the structure shown inFIG.4in order to increase a bonding efficiency and efficiently arranging the spaced area.

The spaced member123shown inFIG.4has hollow unit spaced members123aand may be implemented in a two- or three-dimensional structure with first spaced portions123bby the hollow structure of the unit spaced members123a. That is, the unit spaced member123amay have various cross-sections such as a polygon, a circle, and an ellipse. The unit spaced members123are arranged in contact with each other in the figures, but may be non-uniformly arranged such that second spaced portions123cwhich are empty are formed between the unit spaced members123a, with the first spaced portions123bof the unit spaced members123aformed.

FIG.5is a view showing a detailed example of the reflecting unit described in detail with reference toFIGS.3and4. The reflecting unit120according to the present invention, as described above, includes the first reflective member attached to the surface of the printed circuit board and the second reflective member122spaced from and opposite the first reflective member. In particular, a film made of a transparent material such as PET, or the like, may be used as the second reflective member122and the spaced member123spacing the first and second reflective members121and122is formed by patterning a bonding material, thereby defining the spaced area.

In particular, in order to maximize the reflectivity the first reflective member121has an optical film126bonded by a metal reflective layer125that is adhesives (primer) T1and T2, in which the optical film126may also be stacked on a release film128through a bonding material (PSA)127.

In the structure shown inFIG.5, unlike the embodiment of the first reflective member, the first reflective member121may be formed by using white PET (white polyethylene terephthalate) in a reflective structure that reflects light.

FIG.6is a table for comparing the degrees of improvement of luminance in a lighting apparatus when the reflecting unit according to the present invention is implemented (CIE X and CIE Y are color coordinates).

(A) in the table shows luminance measured when only one reflective member made of Ag was formed on the printed circuit board in the structure ofFIG.3, (B) shows the resultant value of improvement of luminance, comparing the structure A of the related with the structure of the reflecting unit according to the present invention, that is, when the bonding pattern material was silicon, the pattern ofFIG.4was formed, and the first reflective member was made of Ag.

Further, (C) shows the resultant value of improvement of luminance compared with the structure of (A) of the related art, when the first reflective member was made of white PET (white polyethylene terephthalate), unlike (B).

According to the measured result, when luminance was 6605 nit in (A), luminance was 7468 nit, about 13% improved in the structure of (B), and for (C) in which the reflecting unit contained white PET (white polyethylene terephthalate) according to the present invention, luminance was 8472 nit, increased by 28.6% in comparison to (A). That is, it is possible to achieve a result of maximizing the luminance when the structure (spaced area) formed by patterning a bonding material layer is formed and white PET (white polyethylene terephthalate) is used.

2. 2. Second Embodiment

FIG.7is a view showing another embodiment of a lighting apparatus according to the present invention.

That is, the second embodiment according to the present invention implements a structure in which a resin layer is stacked on the printed circuit board of the first embodiment. The configuration of the resin layer corresponds to replacing a light guide plate that is used in a light device of a liquid crystal display and performs a function of guiding light emitted from a light source forward.

Referring toFIG.7, a lighting apparatus according to the present invention further includes a plurality of LEDs130formed on a printed circuit board110and a resin layer140that diffuses and guides emitted light toward the front.

That is, the resin layer140is stacked to surround the LEDs130and performs a function of diffusing light emitted to sides from the light sources. That is, the function of a light guide plate of the related art can be performed by the resin layer140.

Obviously, the resin layer may be basically made of any material as long as the material can diffuse light. For example, according to an embodiment of the present invention, the main material of the resin layer may be resin of which the main material is urethane acrylate oligomer. For example, a substance made by mixing urethane acrylate oligomer that is composite oligomer with a polymer type that is polyacryl. Obviously, a monomer mixed with IBOA (isobornyl acrylate), HPA (Hydroxylpropyl acrylate, or 2-HEA (2-hydroxyethyl acrylate), which is dilutable reactive monomer and a photoinitiator (for example, 1-hydroxycyclohexyl phenyl-ketone) or an antioxidant may be mixed, as and additive.

Further, the resin layer140may include a light diffuser141to increase diffusion and reflection of light. It is preferable to contains the light diffuser of 0.01˜0.3 wt % of the entire weight of the resin layer. That is, the light emitted to sides from the LED can be diffused and reflected through the resin layer140and the light diffuser141and travel upward.

Therefore, it is possible to further increase the reflection together with the reflecting unit120according to the present invention. Accordingly, as the resin layer is disposed, it is possible to reduce the entire thickness of the product by greatly decreasing the thickness of the light guide plate of the related art and to provide common usability for flexible displays because ductility is provided.

3. 3. Third Embodiment

The structure of a lighting apparatus according to the third embodiment in which an optical pattern layer that promotes light diffusion is formed on the resin layer is described as a structure improved from the structure of the second embodiment.

That is, referring toFIG.8, a lighting apparatus according to the present invention can be implemented in a structure including an optical pattern layer150disposed on the resin layer140and having an optical pattern151in the structure shown inFIG.7.

In particular, the optical pattern layer150may include a bonding pattern layer150defining a second air region152surrounding the optical pattern. That is, the bonding pattern layer153defines a separate space (second spaced area) having a uniform pattern on the optical pattern151and an adhesive is applied to the other portions for bonding.

That is, in the structure shown in the figure, for the arrangement relationship of the optical pattern layer150and the bonding pattern layer153, the optical pattern layer150includes a first substrate150A and a second substrate150B which include the optical pattern inside them while the bonding pattern layer153is applied to the portions other than the second spaced area152surrounding the light shield pattern, such that the first substrate150A and the second substrate150B are bonded.

That is, the optical pattern151may be implemented by a light shield pattern formed to inhibit concentration of light emitted from the LED130, and for this configuration, it is necessary to align the optical pattern151with the LEDs130, and an adhesive is applied to ensure a fixing force.

The first substrate150A and the second substrate150B may be made of a material having good light transmissivity, for example PET. In this case, the optical pattern151disposed between the first substrate150A and the second substrate150B basically has a function of inhibiting concentration of light emitted from the LEDs, may be implemented by light shield printing on any one of the first substrate150A or the second substrate150B, and the substrates can be bonded and aligned by applying an adhesive to surround the light shield pattern. That is, the structure that bonds the first substrate150A and the second substrate150B makes it possible to achieve a function of fixing the printed light shield pattern151. Further, the bonding layer may be made of, for example, thermoset PSA, a thermoset adhesive, or a UV-curable PSA type material.

When the bonding pattern layer153is formed and bonded in a pattern structure for forming the second spaced area152, strong hot spot or arm portion generated when the bonding material overlaps the light shield pattern can be inhibited, and uniformity of light can be increased by a spaced layer.

The lighting apparatus having the structure described above, according to the present invention, may include a diffusion member170on the resin layer140, in addition to the configuration described above, and may further include an spaced module160having a third spaced area161between the diffusion member170and the optical pattern layer150. Further, a prism sheet and a protective sheet may be additionally disposed on the diffusion member.

FIGS.9A-9Bare conceptual views showing the configuration of the optical pattern151and the bonding pattern layer153, and the second spaced area152defined by them.

When the bonding pattern layer153is formed in a structure surrounding the optical pattern151printed in a specific pattern on the first substrate by a bonding material, a predetermined separate space is formed and the second substrate150B is bonded, such that the separated space is closed with a spaced layer, which is defined as the second spaced area. The plane shape of the first spaced area152formed by the bonding pattern layer153may be implemented in various shapes, such as a circle, an ellipse, a rectangle, a square, and a polygon. Further, the bonding pattern layer may be made of, for example, thermoset PSA, a thermoset adhesive, or a UV-curable PSA type material.

Further, the optical pattern151is preferably formed in a light shield pattern to achieve a partial light shield effect in order to inhibit deterioration of optical properties or yellowish of yellow light due to excessive intensity of light. That is, it is possible to print a light shield pattern by using light shield ink such that light is not concentrated.

The optical pattern may be implemented to adjust the degree of blocking light or the degree of diffusion of light in one optical pattern, in order not to completely block light, but partially block and diffuse light. Further, more preferably, the optical pattern according to the present invention may be implemented in an overlap printing structure of a composite pattern. The overlap printing structure is a structure implemented by forming one pattern and printing another pattern shape thereon.

For example, the optical pattern151may be implemented in an overlap printing structure of a diffusion pattern formed by light shield ink containing any one or more selected from TiO2, CaCO3, BaSO4, Al2O3, and Silicon on the underside of a macromolecular film in the emission direction of light and a light shied pattern using light shield ink containing Al or a mixture of Al and TiO2. That is, a double structure may be possible to form a diffusion pattern on the surface of a macromolecular film by white printing and then forming a light shield pattern thereon, or in the opposite order. Obviously, the design of the pattern may be changed in various ways in consideration of the efficiency and intensity of light, and the light shield rate. Alternatively, a triple structure may be possible by forming a light shield pattern, which is a metal pattern at the middle layer in a sequentially stacked structure, and forming a diffusion pattern on and under the light shield pattern. It is possible to implement the triple structure by selecting the materials, and a preferred example is to implement one of diffusion patterns by using TiO2having high a high refractive index and implement the other diffusion pattern by using CaCO3and TiO2which has high optical stability and tone, such that it is possible to ensure efficiency and uniformity of light by using the triple structure that implements a light shield pattern by using Al that is easily covered. In particular, CaCO3finally implements white light by reducing exposure of yellow light such that more stable light having high efficiency can be implemented, and inorganic materials having a similar structure, in which the particle size is large, such as BaSO4, Al2O3, and Silicon light diffusers, may be used, other than CaCO3. Further, it is preferable to form the optical pattern by adjusting pattern density such that pattern density decreases as it becomes far from the LED in the emission direction in terms of light efficiency.

Further, the inhibit invention may further include an spaced module disposed between the optical pattern layer150and the diffusion member170.

FIGS.10A-10Dare views showing an example of forming the spaced module disposed between the optical pattern layer150and the diffusion member170shown inFIG.8.

That is, according to the configuration of the lighting apparatus according to the present invention, it is possible to add a structure having a spaced layer (third spaced area160) between the optical pattern layer150and the diffusion member170and to achieve an effect that diffuses light emitted from the light source and improve uniformity of the light by using the third spaced area160. Further, it is preferable to make the third spaced area1600.01˜2 mm thick in order to minimize a difference of the light passing through the resin layer140and the optical pattern layer150.

The third spaced area160may be formed by a structure in which a spaced layer can be formed under the diffusion member and it is determined as an “air gap module”, including the third spaced area implemented by the structure.

The spaced module includes both a method of implementing a spaced area (spaced layer) by machining the diffusion member and a configuration of forming a spaced area by forming a specific structure under the diffusion member.

That is, as shown inFIG.10A, the third spaced area160may be implemented by forming a spacer171under the diffusion member170, or as shown inFIG.10B, the third spaced area160may be implemented in the structure of a bridge172by patterning the lower portion of the diffusion member and attaching it to the lower layer.

The integral structure may be modified in various ways in accordance with the patterned shape, that is, the pattern of forming the spaced area, and accordingly the shape of the bridge may be modified in various ways, which is also included in the spirit of the present invention. Further, as in the structure shown inFIG.10C, it may be implemented in a structure of forming the spaced area160by using a specific structure, other than the method of patterning the underside of the diffusion member. Obviously, the structure is a structure of forming the bridge174with a spacer member and the spirit of the present invention includes this method, such that various modified examples that can implement a spaced layer under the diffusion member also correspond to the spirit of the present invention.

As shown inFIG.10D, similar to the configuration ofFIG.10Bthat patterns the diffusion member or the configuration ofFIG.10Cthat uses a specific structure, it may be possible to form the spaced areas160and161in a plurality of layers by using the structures175and176that can implement independent spaced layers.

The lighting apparatus according to the present invention can be applied to an LCD by the following configuration and operation. In the lighting apparatus according to the present invention, the LEDs130may be side emission type of LEDs.

Referring toFIG.8, light is emitted to sides from the side emission type of LED130, the emitted light is reflected and diffused by the resin layer140formed instead of a light guide plate of the related art, the light is inhibited from being concentrated by the optical pattern layer150, and a difference of flight can be minimized by the third spaced area formed under the diffusion member. In particular, the reflectivity can be further improved by the reflecting unit120according to the present invention which is disposed between the resin layer140and the printed circuit board110, such that efficiency of light can be maximized and luminance can be improved. In particular, in the reflecting unit120according to the present unit, it is possible to adjust the reflectivity by varying the design for implementing the spaced areas by patterning the bonding material layer while it is possible to implement different reflectivity and colors in accordance with the type. Further, it is possible to adjust the reflectivity in accordance with the optical property and thickness of the second reflective member122.

Consequently, the reflective efficiency of the light from the reflecting unit120and the reflective pattern124according to the present invention increases, such that it is possible to guide the light forward. The light passing through the resin layer140, as described above, is diffused or blocked by the optical pattern151formed on the optical pattern layer150and the optical property of the refined light is refined again through the spaced module formed under the diffusion member, such that the uniformity can be increased, and the light travels into the LCD panel in white light through the optical sheets, such as the additional prism sheet180and the DBEF190.

As described above, it is possible to maximize the reflective efficiency by the structure having the spaced areas of the reflecting unit in the lighting apparatus according to the present invention, and to reduce the thickness and the number of light sources by removing the structure of a light guide plate, applying side emission type of LEDs for the light sources, and guiding light to be diffused and reflected by the resin layer. Meanwhile, it is possible to improve optical properties by making it possible to control reduction of luminance and uniformity due to the decrease of the light sources by using the reflective pattern, the light shield pattern, and the spaced areas of the spaced module.

The detailed embodiments of the present invention were described above. However, it is possible to modify the present invention in various ways without departing from the scope of the present invention. The scope of the present invention should not be construed as being limited to the embodiments described above, but determined by equivalents to claims, in addition to claims.

INDUSTRIALLY AVAILABILITY

The present invention according to the present invention can be applied to various lamps that require lighting, such as lamps for vehicles, home lighting devices, and industrial lighting devices. The lamps for vehicles are obviously the headlight, interior and exterior lamps, and rear light.