RELATED APPLICATION

[0001] This application claims the benefit of priority to Korean Application No. 10-2020- 0025357, filed on February 28, 2020. The above-referenced application is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to an optical lens and a tight emitting module comprising the same. More specifically, the present disclosure relates to an optical lens installed on an LED panel to control a path of emitted tight.

BACKGROUND ART

[0003] In general, a plurality of light emitting modules are arranged in a backlight unit used in a liquid crystal display (LCD). The light emitting module includes a light emitting element and a diffusion lens, and the tight emitting element may use, for example, a light emitting diode (LED, hereinafter referred to as LED). The LED has been widely used as a light source in recent years due to its small size and low power consumption. Since light emitted from the LED has relatively high straightness, a diffusion lens is used to disperse the light emitted from the light emitting element at a wide angle to be emitted. The plurality of light emitting modules may irradiate light to a wide area of the backlight unit through the diffusion lens.

[0004] Types of diffusion lens include a refractive diffusion lens and a reflective diffusion lens. The refractive diffusion lens basically has a structure that refracts light by forming an emission surface of a lens through which light passes into a curved surface.

[0005] In Japanese Patent Registration No. 6,294,635, disclosed is a surface light source device having a surface extending concavely from a central axis to reflect light. However, since the corresponding surface light source device is not provided with a configuration capable of re-reflecting the light reflected on the surface, there is a problem in that it is difficult to implement a sufficient level of light diffusion.

SUMMARY

[0006] Various embodiments of the present disclosure have been made in efforts to improve light diffusivity by increasing an amount of light to be reflected or refracted inside a lens. In addition, various embodiments of the present disclosure have been made in efforts to provide an optical lens and a light emitting module including the same capable of minimizing the occurrence of luminance spots and increasing an amount of light directed in a lateral direction.

[0007] According to an embodiment of the present disclosure, there is provided an optical lens for diffusing light generated from a light source. The optical lens includes light incident part formed concavely upward in a height direction so that light generated from the light source is incident from the center of the lens; a light reflecting part configured to reflect at least some of light passing through the light incident part from an upper side of the light incident part in the height direction; a light emitting part configured to emit the light reflected by the light reflecting part from an outer side of the light reflecting part in a radial direction; and rear surface part disposed around the light incident part at the outer side of the light incident part in the radial direction to form a concave groove upward in the height direction, wherein the light reflecting part may include a first reflecting part configured as a curved surface extending concavely upward in the height direction and a second reflecting part disposed at an outer side of the first reflecting part in a radial direction to extend flatly from the first reflecting part in the radial direction, and a micro pattern may be formed on at least a part of the rear surface part.

[0008] According to an embodiment, at least some of the light reflected by the first reflecting part may be configured to be reflected by the second reflecting part and then emitted to the light emitting part. [0009] According to an embodiment, the rear surface part may include a first rear surface part formed concavely upward in the height direction; and a second rear surface part formed between the first rear surface part and the light incident part and having a peak height lower than that of the first rear surface part.

[0010] According to an embodiment, the light incident part may include a first incident part extending to a point of inflection from the central axis of the light incident part; and a second incident part having a different curvature from the first incident part and extending from the point of inflection in the radial direction.

[0011] According to an embodiment, a micro pattern may be formed on a portion of an edge of the second incident part.

[0012] According to an embodiment, the micro pattern may be formed on the second rear surface part.

[0013] According to an embodiment, the first rear surface part may include a first partial surface formed convexly upward from the bottom surface parallel to the radial direction in the height direction; a second partial surface extending flatly from the first partial surface; and a third partial surface extending from the second partial surface to the bottom surface.

[0014] According to an embodiment, the micro pattern may be formed on the second partial surface.

[0015] According to an embodiment of the present disclosure, a light emitting module may include a printed circuit board; a light emitting element mounted on the printed circuit board; and an optical lens installed on the printed circuit board to be positioned above the light emitting element and controlling the light emitted from the light emitting element.

[0016] According to the embodiments of the present disclosure, it is possible to improve light diffusivity by forming a rear surface part under the optical lens. In addition, it is possible to decrease an amount of light directed upward and increase an amount of light directed toward the side by forming a micro pattern on the light incident part and the rear surface part of the optical lens.

BRIEF DESCRIPTION OF DRAWINGS

[0017] FIG. 1 is a perspective view illustrating a light emitting module including an array of optical lenses according to an embodiment of the present disclosure.

[0018] FIG. 2 is a perspective view illustrating a configuration of the optical lens according to an embodiment of the present disclosure when viewed from the top.

[0019] FIG. 3 is a perspective view illustrating a configuration of the optical lens illustrated in FIG. 2 when viewed from the bottom.

[0020] FIG. 4 is a cross-sectional view of the optical lens illustrated in FIG. 2 taken along the line I-I.

[0021] FIG. 5 is a diagram for describing an optical path to a light reflecting part of the optical lens illustrated in FIG. 4.

[0022] FIG. 6 is a diagram for describing an optical path to a light incident part of the optical lens illustrated in FIG. 4.

[0023] FIG. 7 is a diagram for describing an optical path to a rear surface part of the optical lens illustrated in FIG. 4.

[0024] FIG. 8 is a partial cross-sectional view for describing a configuration of an optical lens according to another embodiment of the present disclosure.

[0025] FIG. 9 is a perspective view for describing a configuration of an optical lens according to yet another embodiment of the present disclosure. [0026] FIG. 10 is a cross-sectional view of the optical lens illustrated in FIG. 9 taken along the line I-I.

[0027] FIG. 11 is a cross-sectional view of the optical lens illustrated in FIG. 9 taken along the line II-II.

[0028] FIG. 12 is a table illustrating results of a luminance experiment according to a size of the rear surface part illustrated in FIG. 8.

[0029] FIG. 13 is a graph showing the luminance according to a size of the rear surface part illustrated in FIG. 8.

[0030] FIG. 14 is a graph showing relative luminance values according to a size of the rear surface part illustrated in FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Embodiments of the present disclosure are exemplified for the purpose of describing the technical spirit of the present disclosure. The scope according to the present disclosure is not limited to embodiments to be described below or to detailed descriptions of these embodiments.

[0032] All technical and scientific terms used in the present disclosure, unless defined otherwise, have meanings generally understood by those skilled in the art to which the present disclosure pertains. All terms used in the present disclosure are selected for the purpose of more clearly describing the present disclosure and are not selected to limit the scope according to the present disclosure.

[0033] As used in this disclosure, expressions such as “comprising”, “providing”, “having”, etc. will be understood as open-ended terms that imply the possibility of including other embodiments, unless otherwise stated in the phrases or sentences in which the expressions are included. [0034] The expression of singular forms described in the present disclosure may include the meaning of plural forms unless otherwise stated, and this is applies even to the expressions of singular forms described in the appended claims.

[0035] Expressions of “first”, “second”, etc. used in the present disclosure are used to distinguish a plurality of components from each other, and do not limit the order or importance of the corresponding components.

[0036] In the present disclosure, when it is mentioned that a component is “connected” or “accessed” to another component, it should be understood that the component may be directly connected to or accessed to the other component, or may be connected or accessed via new other components.

[0037] Direction indicators such as “upward” and “up” used in the present disclosure are represented based on a direction in which a lens is positioned with respect to a light emitting element in the accompanying drawings, and direction indicators such as “downward” and “down” refer to opposite directions thereto. The lens and the light emitting element illustrated in the accompanying drawings may also be aligned differently, and the direction indicators may be interpreted accordingly.

[0038] A coordinate system shown in the drawings of the present disclosure illustrates an X-axis and a Z-axis. The X-axis direction means a direction parallel to a radial direction of the optical lens, and the Z-axis direction means a direction parallel to a height direction of the optical lens. In addition, the radial direction may mean a direction far away from a central axis direction of the optical lens.

[0039] However, hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the accompanying drawings, the same or corresponding components may designate the same reference numerals. In addition, in the following description of the exemplary embodiments, it may be omitted to repeatedly describe the same or corresponding components. However, even if the description of the component is omitted, it is not intended that such component is not included in any exemplary embodiment.

[0040] FIG. 1 is a perspective view illustrating a light emitting module 1000 including an array of optical lenses according to an embodiment of the present disclosure.

[0041] A backlight unit (not illustrated) is disposed at the rear of a liquid crystal display (not illustrated) to irradiate light toward the front surface of the liquid crystal display, thereby implementing an identifiable image on the display device. The light emitting module 1000 included as a part of the backlight unit (not illustrated) may include an optical lens 100, a light emitting element 10, and a printed circuit board (PCB) 30.

[0042] The light emitting element 10 may be mounted on the PCB 30, and the PCB 30 may be configured to control the light emitting element 10 and supply power to the light emitting element 10. The light emitting element 10 may be configured by, for example, an LED lamp. In order to control and diffuse light emitted from the light emitting element 10, the optical lens 100 may be installed on the PCB 30 to be positioned above the light emitting element 10

[0043] In FIG. 1 , a plurality of light emitting elements 10 may be mounted in a matrix array on the PCB 30 having an area of a predetermined size so as to have regular intervals from each other. The optical lens 100 may be provided in the number corresponding to the number of the plurality of light emitting elements 10 and may be installed on the PCB 30 to be positioned above each light emitting element 10.

[0044] Abonding part 170 may be formed on a bottom surface 101 of the optical lens 100. The bonding part 170 may be bonded to a position indicating part 20 formed on the PCB 30. Aplurality of bonding parts 170 may be provided on edge regions of the bottom surface 101.

[0045] FIG. 2 is a perspective view illustrating a configuration of the optical lens 100 according to an embodiment of the present disclosure when viewed from the top. FIG. 3 is a perspective view illustrating a configuration of the optical lens 100 illustrated in FIG. 2 when viewed from the bottom. FIG. 4 is a cross-sectional view of the optical lens 100 illustrated in FIG. 2 taken along the line I-I.

[0046] Referring to FIGS. 2 and 3, the optical lens 100 may include a light incident part 110, a light reflecting part 120, a rear surface part 130, and a light emitting part 160. Referring to FIG. 4, the optical lens 100 may have a symmetrical shape with respect to a central axis CL. In addition, the optical lens 100 may have a pillar shape in which a height direction (Z direction) becomes a central axis as a whole. That is, when the optical lens 100 is cut in a plane perpendicular to the Z axis, a cross section having sides composed of four convex curves as a whole may be shown.

[0047] The light incident part 110 may be formed concavely upward in the height direction (Z direction) so that the light emitted from the light emitting element 10 is incident. The light incident part 110 may have a conical shape as a whole. A conical surface forming the conical shape may be configured as a curved surface which is convex downward in the height direction (Z direction). The detailed configuration of the light incident part 110 will be described below.

[0048] The light emitting part 160 may include an emission surface 161 through which the light passing through the light incident part 110 or refracted by the light incident part 110 is emitted to the outside of the optical lens 100. The emission surface 161 may be configured as a curved surface that is substantially convex in a radial direction RD. A flange part 180 may be formed below the light emitting part 160. The flange part 180 does not substantially affect the optical path.

[0049] The light reflecting part 120 formed on the upper side of the optical lens 100 in the height direction (Z direction) is formed concavely downward in the height direction (Z direction) to form first and second reflecting parts 121 and 122 on which some of the light passing through the light incident part 110 is reflected. The fust reflecting part 121 may be configured as a curved surface concavely extending from a position spaced upward from the center position of the light incident part 110 in the height direction (Z direction). The first reflecting part 121 may have a substantially conical shape. That is, the optical lens 100 may have a shape recessed downward from the upper end.

[0050] The first reflecting part 121 may be formed to be tapered in the direction of the central axis CL of the optical lens 100, and the second reflecting part 122 may extend flatly from the first reflecting part 121 so as to be parallel to the radial direction RD. The second reflecting part 122 may be formed as a flat surface (see FIG. 4), but is not necessarily limited thereto, and may be formed as an angled surface (see FIG. 8). Unlike the first reflecting part 121, the second reflecting part 122 has a flat surface to improve brightness in the direction of the central axis in the optical lens 100. On the other hand, it is obvious that the second reflecting part 122 may be formed not only with a flat surface, but also with a predetermined curvature capable of improving brightness in the direction of the central axis CL in the optical lens 100. Some of the light passing through the light incident part 110 may be reflected by the first reflecting part 121 or the second reflecting part 122 to be emitted through the emission surface 161.

[0051] The rear surface part 130 is formed at the outer side of the light incident part 110 in the radial direction RD, and may be configured to change the path of light passing through the light incident part 110 or the path of light reflected by the light reflecting part 120. The rear surface part 130 may form a groove that is concave upward in the height direction (Z direction) from the outer side of the light incident part 110 in the radial direction. The rear surface part 130 may include a fust rear surface part 140 and a second rear surface part 150. The second rear surface part 150 may be formed between the first rear surface part 140 and the light incident part 110 and may have a peak height lower than that of the first rear surface part 140.

[0052] Referring to FIG. 4, when viewing a cross section of the optical lens 100, the first rear surface part 140 and the second rear surface part 150 may have a substantially triangular or rhombus cross-section. The first rear surface part 140 may include a first partial surface 141 formed convexly upward from the bottom surface 101 parallel to the radial direction RD in the height direction (Z direction), a second partial surface 142 extending flatly from the first partial surface 141, and a third partial surface 143 extending downward from the second partial surface 142 to the bottom surface 101 in the height direction (Z direction). The first partial surface 141 may be formed to be connected to the second rear surface part 150.

[0053] FIG. 5 is a diagram for describing an optical path to the light reflecting part 120 of the optical lens 100 illustrated in FIG. 4.

[0054] Light LI represents light which is reflected by the first reflecting part 121 and then emitted through the emission surface 161. In general, the light LI may be light having an angle of approximately 45° or less with respect to the central axis CL. Since the light LI is directed upward in the height direction (Z direction) while passing through the emission surface 161, the structure of the second reflecting part 122 may be provided to further increase light diffusivity.

[0055] Light L2 is some of the light reflected by the first reflecting part 121 and is configured to be reflected by the second reflecting part 122 and then emitted to the light emitting part. The light L2 may be configured by light having an angle of approximately 45° or more with respect to the central axis CL. Since the light L2 is reflected by the second reflecting part 122 and then directed downward in the height direction (Z direction), the light diffusivity may be further improved.

[0056] FIG. 6 is a diagram for describing an optical path to the light reflecting part 110 of the optical lens 100 illustrated in FIG. 4. Lights L3, L4, and L5 illustrated in FIG. 6 represent the same light as lights L3, L4, and L5 illustrated in FIG. 5.

[0057] The light incident part 110 may include a first incident part 111 extending to a point of inflection PI from the central axis CL and a second incident part 112 having a different curvature from the first incident part 111 and extending from the point of inflection PI in the radial direction RD. A micro pattern may be formed on a portion 113 of an edge of the second incident part 112.

[0058] The light L3 represents light which is reflected by the second incident part 112 and directed downward in the height direction (Z direction). If the light emitted from the light emitting element 10 is directed toward the first incident part 111, the light may pass through the first incident part 111 rather than being reflected because the incident angle is smaller than a total reflection angle.

[0059] The light L4 represents light passing through the portion 113 of the edge on which the micro pattern is formed. Since the micro pattern is formed on the portion 113 of the edge , an amount of the light L4 passing through the portion 113 of the edge may be greater than that of the light L4 reflected to the portion 113 of the edge, and the light may be refracted at various angles to be spread. Accordingly, light diffusivity may be improved due to such a micro pattern.

[0060] The light L5 represents light which is reflected on the second rear surface part 150 and directed downward in the height direction (Z direction). The light L5 passes through the light incident part 110 to be directed to the second rear surface part 150. Since the incident angle of the light L5 corresponds to an angle substantially totally reflected on the second rear surface part 150, the light L5 may be reflected on the second rear surface part 150 rather than passing through the second rear surface part 150. Meanwhile, a micro pattern may be formed on the second rear surface part 150. In this case, since the angle of the light L5 that is reflected on the second rear surface part 150 and then directed downward in the height direction (Z direction) may be more variously spread, light diffusivity may be improved.

[0061] FIG. 7 is a diagram for describing an optical path to the rear surface part 130 of the optical lens 100 illustrated in FIG. 4. FIG. 7 mainly describes the optical path to the first rear surface part 140.

[0062] The first rear surface part 140 may include a first partial surface 141 formed convexly upward from the bottom surface 101 parallel to the radial direction RD in the height direction (Z direction), a second partial surface 142 extending substantially flatly from the first partial surface 141, and a third partial surface 143 extending from the second partial surface 142 to the bottom surface 101. Meanwhile, the second partial surface 142 may be formed to be inclined at a predetermined angle with the bottom surface 101. A micro pattern may be formed on the second partial surface 142. [0063] The light L6 represents light that is refracted while passing through the first rear surface part 140. The light L6 may be first refracted while passing through the first partial surface 141, and then refracted while passing through the third partial surface 143. If the micro pattern is not formed on the portion 113 of the edge of the light incident part 110, the light L6 may be reflected on the bottom surface 101, and light diffusivity may be weakened. Accordingly, when the micro pattern is formed on the portion 113 of the edge of the light incident part 110, the light L6 passing through the first partial surface 141 may be generated, and the fight diffiisivity may be improved.

[0064] The light L7 represents light that is refracted while passing through the first rear surface part 140. The light L7 may have a smaller angle with the central axis CL than that of the fight L6. The light L7 may first pass through the first partial surface 141, and then be reflected on the second partial surface 142. Next, the light L4 may be reflected on the third partial surface 143 and then directed downward in the height direction (Z direction). Accordingly, since the light L7 may become fight directed toward the light emitting element 10 again, the light dilfusivity may be improved. If the micro pattern is formed on the second partial surface 142, since the angle at which the light L7 spreads to the second partial surface 142 may vary, the light diffusivity may be improved.

[0065] FIG. 8 is a partial cross-sectional view for describing a configuration of an optical lens 100 according to another embodiment of the present disclosure. Aduplicated description of the configuration described in the above-described embodiment will be omitted. Part A represents an enlarged upper edge portion of the optical lens 100, and part B represents an enlarged lower edge portion of the optical lens 100.

[0066] The second reflecting part 123 may be configured with at least one inclined surface forming a predetermined angle with the radial direction RD. In this case, the second reflecting part 123 may form a pattern in which the inclmed surfaces are repeated. If light is reflected by the second reflecting part 123 having the pattern, since an angle after being reflected by the second reflecting part 123 may be dispersed, the light diffusivity may be improved. Meanwhile, the second reflecting part 123 may also be configured as a flat surface as the shape illustrated in FIG. 4.

[0067] The radial direction RD may form a predetermined angle a with an average line AL formed by the second reflecting part 123. The predetermined angle a may be, for example, between 1° and 5°. In this case, since the amount of light directed downward in the height direction (Z direction) may be increased, the light diffusivity may be improved.

[0068] A stepped surface 162 may be formed between the emission surface 161 and the flange part 180. The formation of the stepped surface 162 may be configured to have a curvature different from that of the emission surface 161. Accordingly, since the refraction degree of the light passing through the emission surface 161 is different from the refraction degree of the light passing through the stepped surface 162, the light diffusivity may be improved.

[0069] FIG. 9 is a perspective view for describing a configuration of an optical lens 200 according to yet another embodiment of the present disclosure. FIG. 10 is a cross-sectional view of the optical lens 200 illustrated in FIG. 9 taken along the line I-I. FIG. 11 is a cross- sectional view of the optical lens 200 illustrated in FIG. 9 taken along the line II-II. A duplicated description of the configuration described in the above-described embodiment will be omitted.

[0070] The optical lens 200 may include a light incident part 210, a light reflecting part 220, a rear surface part 230, and a light emitting part 260. The light reflecting part 210 may include a first reflecting part 221 and a second reflecting part 222. When viewed from the top, the light reflecting part 210 may have a rectangular shape having a curved corner. In addition, the first reflecting part 221 may have a circular shape, and the second reflecting part 221 may be configured by four partial surfaces by removing the circular shape from the rectangular shape. Each partial surface may have a curved side (i .e., a plurality of arc lines).

[0071] Compared with the light reflecting part 120 illustrated in FIG. 2, a diameter of the first reflecting part 221 illustrated in FIG. 9 was formed larger than a diameter of the first reflecting part 121 illustrated in FIG. 2. Accordingly, edges of the first reflecting part 221 may be almost in contact with the edges of the light reflecting part 210. Therefore, an area of the second reflecting part 222 illustrated in FIG. 9 is considerably smaller than the area of the second reflecting part 122 illustrated in FIG. 2.

[0072] Since FIG. 10 is a cross-sectional view of the optical lens 200 illustrated in FIG. 9 taken along the line I -I, the second reflecting part 222 is not illustrated in FIG. 10. On the contrary, since FIG. 11 is a cross-sectional view of the optical lens 200 illustrated in FIG. 9 taken along the line II-II, the second reflecting part 222 is illustrated in FIG. 11. The second reflecting part 222 may extend flatly from the first reflecting part 221. The second reflecting part 222 may be configured as a flat surface, but is not necessarily limited thereto, and may be configured as an angled surface (see FIG. 8).

[0073] FIG. 12 is a table illustrating results of a luminance experiment according to a size of the rear surface part 130 illustrated in FIG. 8. FIG. 13 is a graph showing the luminance according to a size of the rear surface part 130 illustrated in FIG. 8. FIG. 14 is a graph showing relative luminance values according to a size of the rear surface part 130 illustrated in FIG. 8. In FIG. 10, an X-axis represents positions of the optical lens 100 in the radial direction RD, and a Y-axis represents different luminance values at the corresponding positions. In addition, the X-axis represents positions of the optical lens 100 in the radial direction RD, and the Y-axis represents a ratio (%) obtained by dividing the luminance value corresponding to each position by a peak luminance value.

[0074] Referring to FIG. 8, a height H of the optical lens 100 may be defined as a shortest distance between the second reflecting part 123 and the bottom surface 101. In addition, a thickness T of the first rear surface part 140 may be defined as a shortest distance between a peak point of the first rear surface part 140 and the second reflecting part 123. That is, as the thickness T increases, the peak point of the first rear surface part 140 is low, and as the thickness T decreases, the peak point of the first rear surface part 140 is high.

[0075] Referring to FIG. 12, results of luminance experiments according to Experimental Examples 1 to 11 are described. During the experiments, a height H was fixed to 2.95 mm. A first column represents the number (No.) of Experimental Examples. A second column represents Experimental Examples distinguished from Experimental Examples 1 to 11. A third column represents the thickness T value. A fourth column represents a ratio T/H of the thickness T to the height H as % unit. A fifth column represents a peak luminance Lv at a position of the central axis CL according to each thickness T. A sixth column represents a judgment result according to experiment results of each of Experimental Examples. The unit of the peak luminance Lv may be expressed as Nit. Here, it may be judged that as the peak luminance Lv is lower, light diffusivity is good, and it may be judged that as the peak luminance Lv is higher, the light diffusivity is low.

[0076] Experimental Examples 1 and 2 were judged as NG, which was meant to be unsuitable for implementation. In Experimental Example 1, the luminance uniformity was not good, and an area where the light was concentrated was shown wide. In addition, in Experimental Example 2, a large amount of emitted light that was totally reflected was shown, but it was found that the amount of light directed toward the central axis CL of the optical lens 100 was large.

[0077] Experimental Examples 10 and 11 were judged as NG, which was meant to be unsuitable for implementation. In Experimental Example 10, a small amount of emitted light that was totally reflected was shown, but it was found that the amount of light directed toward the central axis CL of the optical lens 100 was small In addition, in Experimental Example 11, it was confirmed that the light diffusivity and the light efficiency were deteriorated.

[0078] Experimental Examples 3 to 9 were judged as OK, which was meant to be suitable for implementation. Experimental Example 3 represents UPPER LIMIT, and Experimental Example 9 represents LOWER LIMIT. Accordingly, all of Experimental Examples 3 to 9 were judged as OK. Therefore, it is preferable to implement the thickness T of the optical lens 100 between 1.10 mm and 2.30 mm. Among these Experimental Examples, Experimental Example judged to be the most preferable is Experimental Example 6, in which the thickness T is 1.7 mm. In this case, the peak luminance Lv was measured to be 11,984 Nit. [0079] Referring to FIG. 13, graphs indicated between two straight lines parallel to the X- axis represent Experimental Examples 3 to 9. Referring to FIGS. 13 and 14, it can be seen that in Experimental Examples 3 to 9, the light diffusivity is better implemented than that of the remaining Experimental Examples.

[0080] While the technical idea of the present disclosure has been described with reference to some embodiments and examples illustrated in the accompanying drawings above, it will be appreciated that various substitutions, modifications and changes may be made without departing from the technical idea and scope of the present disclosure that can be understood by those of ordinary skill in the art to which the present disclosure belongs. In addition, it will be appreciated that such substitutions, modifications and changes are to be considered as falling within the scope of the appended claims.