KR101113611B1 - Lens for a lighting unit - Google Patents

Abstract

Embodiments relate to a lens for a lighting unit used in a lighting device, and more particularly, to a lens for a lighting unit that enables an efficient illuminance distribution in the light irradiation. The lens according to the embodiment includes a circular incident surface perpendicular to the optical axis and including a furrow crossing the surface and a prism surface formed on both sides of the furrow surface; And an emission surface for refraction and exiting light incident through the entrance surface.

Description

Lens for Lighting Unit {LENS FOR A LIGHTING UNIT}

Embodiments relate to a lens for a lighting unit used in a lighting device, and more particularly, to a lens for a lighting unit that enables an efficient illuminance distribution in the light irradiation.

Light Emitting Diodes (LEDs) have low power consumption, long lifespans, and can be operated at low cost. Therefore, they are being applied to light sources such as various electronic components, electronic displays, and lighting devices. In addition, there is a lighting device in the art to additionally provide a lens to achieve the intended light distribution characteristics. Generally, a lens for an illumination device is for diffusing light to have a wide irradiation surface and for concentrating high illumination light on a narrow irradiation surface.

Except for lighting devices having a large light emitting surface, most of the lighting devices have the same characteristics as point sources. In other words, the illuminance distribution on the irradiated surface to which light is irradiated from the illumination device is not uniform, and in most cases is circular. In this case, in order to brighten the space of a specific area, several lighting devices are used. Since the illuminance distribution of the irradiation surface is circular, the light emitted from different lighting devices overlaps each other, which wastes power in brightening the space of a specific area. May result. In order to prevent this phenomenon, when the distance between each lighting device is increased, a blind spot where light does not reach between each circular irradiation surface is generated. Therefore, in making the space of a specific area brighter, the nearer the irradiation surface to which light is irradiated from the lighting device to a square, the more uniform the luminance of the whole irradiation surface is, the more efficient the lighting device becomes.

Accordingly, an object of the present invention is to provide a lens required for an efficient lighting device capable of minimizing power consumption while matching the luminance of an irradiation surface to a target luminance.

The lens according to the embodiment includes a circular incident surface perpendicular to the optical axis and including a furrow crossing the surface and a prism surface formed on both sides of the furrow surface; And an emission surface for refraction and exiting light incident through the entrance surface.

A lens according to an embodiment includes a lens including a circular entrance surface perpendicular to an optical axis and an exit surface for refracting light incident through the entrance surface, the entrance surface comprising: a light diffusion surface for spreading light outwardly; And an illuminance enhancement surface that compensates for illuminance in the center of the irradiation surface and is formed in the longitudinal direction of the light diffusing surface passing through the center of the incident surface.

Lens according to the embodiment, the circular incident surface perpendicular to the optical axis; And an emission surface for refracting and exiting light incident through the incident surface, wherein the irradiation area on the surface illuminated by the light emitted from the lens forms an approximate rectangle, and the length of the long side of the approximate rectangle is the light source. 2.5 times the height from the light source to the irradiation surface, the length of the short side of the approximate rectangle is 1.6 times the height from the light source to the irradiation surface, and the UP / RT is 0.88.

Embodiments can provide a lens for a lighting unit used in a lighting device for minimizing blind spots to which light does not reach the irradiation surface.

Embodiments can provide a lens for a lighting unit for use in a lighting device that can reduce the area where light from each lighting device inevitably overlaps in order to eliminate blind spots even though a sufficiently high illuminance has already been achieved.

The embodiment can provide a lens for a lighting unit used in a lighting device that can match a space of the same area to a target illuminance while consuming less power than a conventional lighting device.

The embodiment can provide a lens for a lighting unit used for a lighting device in which the illuminance distribution on the irradiation surface to which light is irradiated from the lighting device shows a distribution of an approximate rectangle.

The embodiment can provide a lens for a lighting unit used in a lighting device that can illuminate at a desired illuminance distribution without using a separate fixture.

The embodiment can improve the light distribution and illuminance distribution of an outdoor lamp such as a street lamp or an outdoor lamp, and can provide a lens for a lighting unit used for a lighting device having an illuminance distribution considering a distance between the street lamp and an outdoor lamp. .

1 is a side sectional view showing a lighting unit according to a first embodiment;
FIG. 2 is a side cross-sectional view of the light emitting part of FIG. 1. FIG.
3 is a plan view of the light emitting unit of FIG. 1;
4 is another example of the light emitting part of FIG. 1;
5 is another example of the light emitting part of FIG. 1;
6 is another example of the light emitting part of FIG. 1;
7 is a side cross-sectional view showing the gap member of FIG.
8 is a perspective view of the gap member of FIG.
9 is a plan view of the gap member of FIG.
10 is a bottom view of the gap member of FIG. 1.
11 is a perspective view of another example of the gap member of FIG.
12 is a plan view of another example of the gap member of FIG. 1;
13 is a bottom view of another example of the gap member of FIG.
14 is a diagram showing an irradiation surface when the illuminance distribution is circular;
15 is a diagram showing an irradiation surface when the illuminance distribution is a square;
Fig. 16 is a side cross-sectional view of a lens in which the incidence surface is composed only of the prism surface and the emission surface is flat;
FIG. 17 is a view showing spatial light distribution by an illumination unit including the lens of FIG. 16; FIG.
Fig. 18 is a side sectional view of the lens in which the incidence surface is composed of only the prism face and the exit face is in the shape of a spherical lens;
FIG. 19 shows spatial light distribution by an illumination unit including the lens of FIG. 18; FIG.
20 is a diagram showing the illuminance distribution by the illumination unit including the lens of FIG. 18.
Fig. 21 is a perspective view of a lens in which the incidence surface is composed of a prism face and a furrow face, and the exit face is in the shape of a spherical lens.
Fig. 22 is a plan view of a lens in which the incidence surface is composed of a prism face and a furrow face, and the exit face is in the shape of a spherical lens.
Fig. 23 is a side cross-sectional view of a lens in which the incidence surface is composed of a prism face and a furrow face, and the exit face is in the shape of a spherical lens.
24 shows an optical path of light emitted from the LED of the lighting unit of FIG. 1.
FIG. 25 is a view showing spatial light distribution by an illumination unit using the lens of FIG. 21; FIG.
FIG. 26 shows illuminance distribution by the illumination unit using the lens of FIG. 21; FIG.
Fig. 27 is a diagram showing the roughness distribution of the irradiated surface according to the FTE Calculator.
FIG. 28 is a view showing spatial light distribution by an illumination unit using the lens of Experimental Example 5. FIG.
29 is a diagram showing the illuminance distribution on the illumination unit using the lens of Experimental Example 5. FIG.
30 is a side sectional view showing a lighting unit according to a second embodiment;
31 is a side sectional view showing a lighting unit according to a third embodiment;
32 is a side sectional view showing a lighting unit according to a fourth embodiment;

In the description of the embodiments, the reference for the top or bottom of each layer is assumed to be above the side with the lens 140, the side with the light emitting portion 101, unless otherwise noted. When a coordinate axis indicating a space is shown in the drawing, the description will be made based on the coordinate axis. In the drawings, the thickness or size of each layer is exaggerated, omitted, or schematically illustrated for convenience and clarity of description. In addition, the size of each component does not necessarily reflect the actual size. Hereinafter, with reference to the accompanying drawings as follows.

1 is a side cross-sectional view showing a lighting unit 100 according to the first embodiment, FIG. 2 is a side cross-sectional view of the light emitting unit 101 of FIG. 1, FIG. 3 is a plan view of the light emitting unit 101 of FIG. 4 is another example of the light emitting unit 101 of FIG. 1, FIG. 5 is another example of the light emitting unit 101 of FIG. 1, and FIG. 6 is another example of the light emitting unit 101 of FIG. 1.

Referring to FIG. 1, the lighting unit 100 includes a light emitting unit 101, a gap member 130, and a lens 140. The lighting unit 100 may be mounted on outdoor lamps such as street lamps and outdoor lamps arranged at regular intervals, and may illuminate with an appropriate light distribution and illuminance distribution for the area between the front of the outdoor lamp and the street lamp and the outdoor lamp.

The light emitting unit 101 includes a plurality of LEDs 120 mounted on the substrate 110, and the arrangement of the plurality of LEDs 120 may be variously changed.

The substrate 110 may include an aluminum substrate, a ceramic substrate, a metal core PCB, a general PCB, and the like. In addition, the substrate 110 may be formed of a material that reflects light efficiently, or the surface may be formed of a color that reflects light efficiently, for example, white, silver, or the like. The plurality of LEDs 120 may include white LEDs, or may selectively use colored LEDs such as red LEDs, blue LEDs, and green LEDs. The emission angle of the LED 120 may include 120 ° to 160 ° or Lambertian.

As shown in FIGS. 2 and 3, the substrate 110 of the light emitting unit 101 has a disc shape having a predetermined diameter D1, and the diameter D1 is a width that can be accommodated under the gap member 130. Can be formed. A flat portion 114 may be formed on one outer circumferential surface of the substrate 110, and the flat portion 114 may identify a coupling position between components of the lighting unit 100 or perform a rotation preventing function.

A plurality of screw holes 113 may be formed on the substrate 110, and screws are inserted into the screw holes 113 to fasten the substrate 110 to a fixture such as a street lamp or an outdoor light, or the substrate 110 may be illuminated. It is fastened to the case of the unit 100. Here, the rivets, hooks, and the like, not the screws, may be inserted into the screw holes 113. The substrate 110 may not have a plurality of screw holes 113.

The light emitting unit 101A of FIG. 3 is arranged in such a manner that eight LEDs 120 are arranged on the substrate 110. For example, eight LEDs 120 may be arranged at regular intervals on a circumference having a predetermined radius at the center of the substrate 110. ) Can be arranged. The eight LEDs 120 may be arranged on an ellipse or not in a circumferential shape.

The light emitting unit 101B of FIG. 4 is arranged in such a manner that ten LEDs 120 are arranged on the substrate 110. For example, eight LEDs 120 are arranged at regular intervals on a circumference having a predetermined radius from the center of the substrate. An example in which two LEDs are arranged in the inner region of the circumference is shown.

The light emitting unit 101C of FIG. 5 is arranged in such a manner that twelve LEDs 120 are arranged on the substrate 110. For example, eight LEDs 120 are arranged at regular intervals on a circumference having a predetermined radius from the center of the substrate. 4 shows an example in which four LEDs 120 are arranged at regular intervals on a circumference of a concentric circle having a radius smaller than the circumference.

The light emitting portion 101D shown in FIG. 6 may be arranged at a position in which the entire LED 120 on a small circumference is rotated by 45 ° with respect to the center of the substrate as compared with FIG. 5.

The arrangement of the LEDs 120 shown in FIGS. 3 to 6 is exemplary, and the spacing between the LEDs 120 arranged on the circumference may not necessarily be a constant interval depending on the shape of the irradiation surface required, and the substrate 110. The arrangement form and the number of the LED 120 above may vary according to the light intensity, light distribution, illuminance distribution, and may be changed within the technical scope of the embodiment. In the drawings or the specification, if the specific light emitting unit 101A, 101B, 101C, 101D having a specific LED 120 arrangement is not specified, and the term light emitting unit 101 is used, a name representing a light emitting unit having such various arrangements is used. Is to use.

7 is a side cross-sectional view illustrating the gap member 130 of FIG. 1, FIG. 8 is a perspective view of the gap member 130 of FIG. 1, FIG. 9 is a plan view of the gap member 130 of FIG. 1, and FIG. 10 is of FIG. 1. Bottom view of the gap member 130, FIG. 11 is a perspective view of another example of the gap member 130 of FIG. 1, FIG. 12 is a plan view of another example of the gap member 130 of FIG. 1, and FIG. 13 is a gap member of FIG. 1. Bottom view of another example of 130.

1 and 7 to 13, the gap member 130 has a ring-shaped reflector 132 having a downwardly inclined surface in the center direction and a ring extending concentrically with the reflector 132. It includes a wall portion 131 of the shape. In addition, since the gap member 130 has a flat ring shape as a whole, the gap member 130 has an opening 133 having a diameter of an inner diameter of the reflecting portion 132.

The reflector 132 may enhance the light efficiency of the lighting device by allowing the light emitted from the LED 120 to be reflected to the outside without disappearing. Since light is emitted toward the upper portion of the reflector 132, the reflector 132 assists in the upward emission of the light.

The bottom surface of the reflecting portion 132 is in contact with the upper circumference of the light emitting portion 101, and the inner circumferential surface of the wall portion 131 is in contact with the outer circumferential surface of the light emitting portion 101, so that the light emitting portion 101 is the gap member 130. Is seated on. In order to prevent the light emitting portion 101 from escaping upward from the gap member 130, the inner diameter of the reflecting portion 132 may be smaller than the inner diameter of the wall portion 131 and the outer diameter of the light emitting portion 101.

 At the same time, the gap member 130 spaces the substrate 110 from the lens 140 at a predetermined interval G1. Since the gap G1 is greater than or equal to the thickness of the LED 120 arranged on the substrate 110, the lens 140 does not press the LED 120, and there is a space between the lens 140 and the substrate 110. 105 can be formed to induce emission angle and light dispersion.

In addition, the gap member 130 prevents direct contact between the other surface except the bottom of the light emitting unit 101 and another member such as a case of the lighting unit. When the gap member 130 is formed of an insulating material, the gap member 130 is formed. And the light emitting portion 101 are insulated. In addition, if the heat dissipation pad of the insulating material is in close contact with the bottom of the light emitting unit 101, the light emitting unit 101 can prevent the occurrence of problems such as electrical short, EMI, EMS, etc. Can be.

The space 105 may be filled with a silicon or silicone resin material. The LED 120 of the light emitting unit 101 is exposed through the opening 133, and the edge 144 of the lens 140 is disposed on an upper surface of the gap member 130.

A flat portion 134 may be formed on one side of the gap member 130, and the flat portion 134 may identify a coupling position between components of the lighting unit 100 or perform a rotation preventing function. For details, the flat portion 114 is formed on one side of the substrate 110, such as the substrate 110 of the light emitting portion 101 illustrated in FIGS. 3 to 6, and the gap illustrated in FIGS. 8 to 13. Assume an embodiment in which the flat portion 134 is formed in the gap member 130 as in the member 130. 10 and 13, the inner surface as well as the outer surface of the flat portion 134 of the gap member 130 is flat, so that the substrate 110 is the gap member while the two flat portions 114 and 134 abut. To be fitted to 130. Since the inner circumferential surface of the wall portion 131 and the outer circumferential surface of the substrate 110 are flat, one surface is not rotated or distorted.

The reflector 132 extends from the upper surface of the wall 131 with a predetermined inclination toward the center of the opening 133. That is, the reflector 132 is inclined at a predetermined inclination angle θ1 around the outer circumference of the opening 133 of the gap member 130. Since the prism surface 142 of the lens 140 is disposed above the inclined surface of the reflector 132, the amount of reflected light may vary depending on the inclination angle θ1 and the width of the reflector 132. The inner opening 133 of the reflector 132 may be formed in a circular shape having a predetermined diameter D2, as shown in FIGS. 8 to 10.

Among the light emitted from the LED 120, the light that reaches the reflector 132 is reflected by the inclined surface of the reflector 132, and passes through the lens 140 to the outside. Therefore, the light emitting device has an additional effect of improving light efficiency as compared to a conventional gap member that does not include the reflector 132. It has already been seen that the gap member 130 according to the present embodiment improves the breakdown voltage characteristic as compared to the conventional gap member.

11 to 13, the gap member 130 may have an electrode passing portion 135 through which a wire or an electrode (not shown) connected to the substrate 110 may pass.

8 to 13, only the gap member 130 having the flat portion 134 is illustrated, and the gap member 130 having the flat portion 134 is a preferred embodiment. However, although the gap member 130 which is generally circular without the flat part 134 may be rotated or distorted between parts, except for this disadvantage, the optical efficiency of the gap member 130 of the embodiment described above and It will have the effect of improving the breakdown voltage characteristics, and therefore it should be understood that the best embodiment is described, not limited to the gap member 130 having the flat portion 134.

Prior to the description of the shape and structure of the lens 140, the lens 140 presented in the embodiment disclosed in connection with the present invention is generally used in the lighting unit 100 mounted to outdoor lighting such as street lights, outdoor lights, etc. Since it is the lens 140, it is necessary to first find out what is the effective illuminance distribution in the lens 140.

Efficient Illuminance Distribution

FIG. 14 is a diagram showing an irradiated surface when the illuminance distribution is circular, and FIG. 15 is a diagram showing an irradiated surface when the illuminance distribution is square.

Referring to FIGS. 14 and 15, the shape of the illuminance distribution from which the light is irradiated from the illumination unit 100 forms a square, as compared with the case where the shape of the illuminance is a circle, the light A2 that is overlapped and wasted is also reduced. It is possible to reduce the blind spot A3, and to reduce the light A1 irradiated to the area where the illumination does not need to shine, indicating that the efficiency is excellent.

The street lamp and outdoor lamp using the lighting unit 100 having a circular illuminance distribution and the street lamp and outdoor lamp using the lighting unit 100 having a square illuminance distribution are compared. Compared to the former, the latter can improve the illuminance distribution between adjacent street lamps or the distribution of illuminance between adjacent outdoor lights, and can reduce or eliminate the blind spot (A3), so the distance between the street lamp or outdoor lamp at the latter is higher than in the former. You can widen it. In addition, it is possible to reduce the number of street lights or outdoor lights required to achieve the required illuminance, thereby reducing the cost of maintenance, management and operation.

In FIG. 15, an example of a square illuminance distribution has been described, but it is more advantageous to have a non-square rectangular illuminance distribution to illuminate a long and long irradiation surface such as a street lamp or an outdoor lamp illuminating a road. Therefore, either one of the rectangular or square illuminance distribution may be advantageous compared to the other depending on the use in which the illumination unit 100 is used.

Hereinafter, the structure of the lens 140 for achieving a rectangular illuminance distribution will be described in order.

<Structure of lens to achieve asymmetric illuminance distribution-incident surface including prism surface>

FIG. 16 is a side cross-sectional view of the lens 140 in which the incident surface 143 is composed of only the prism surface 142 and the exit surface 145 is flat, and FIG. 17 is an illumination unit 100 including the lens 140 of FIG. 16. The spatial light distribution by

Referring to FIG. 17, the light distribution when the illumination unit 100 is viewed from the front in the X-axis direction is shown as B2, and the light distribution when the illumination unit 100 is viewed at the front in the Y-axis direction is shown as B1. appear. The reason why B2 is more widely distributed than B1 is because light is diffused in the Y-axis direction by the prism face 142. Therefore, this asymmetric illuminance distribution becomes relatively rectangular rather than circular illuminance distribution. However, since the prism surface 142 spreads the light outward, the center portion becomes relatively darker than other irradiation surfaces when the illumination unit is viewed in the X-axis direction (B2). In addition, when viewed from the Y-axis direction (B1), the width is narrow and the central portion is relatively darker than other irradiation surfaces.

Therefore, in the lens 140 in which the incident surface 143 includes only the prism surface 142 and the emission surface 145 is flat, the illuminance distribution is not uniform. In addition, in the case of using a plurality of lighting units (100), a lot of unnecessary light overlap is generated, and if you reduce the waste of overlapping light, a dark blind spot is created to still efficiently efficient lighting unit 100 It becomes difficult to operate.

Therefore, the formation of the exit surface 145 as the spherical lens 140 as a structure of the lens 140 to compensate for weakened roughness at the center of the irradiation surface will be described.

 <The structure of the lens to compensate the weakened illumination at the center of the irradiation surface-Lens with spherical exit surface>

FIG. 18 is a side cross-sectional view of the lens 140 in which the incident surface 143 includes only the prism surface 142 and the exit surface 145 has a spherical lens shape, and FIG. 19 is an illumination unit including the lens 140 of FIG. 18. It is a figure which shows the spatial light distribution by 100, and FIG. 20 is a figure which shows the illuminance distribution by the illumination unit 100 containing the lens 140 of FIG.

When comparing FIG. 17 and FIG. 19, compared with the lens 140 whose emission surface 145 is planar, there exists the improvement of the intensity of the light when it sees from the Y-axis (B1), and when it sees from the X-axis (B2), It can be seen that the intensity of the light at is significantly improved. However, the intensity of light at the center is still weak, and referring to FIG. 20, the illuminance distribution on the irradiated surface still shows the shape of a dumbbell or a butterfly wing. As a result, since the lens 140 having the entrance face 143 composed only of the prism face 142 and the spherical exit face 145 still cannot achieve a radiation distribution close to a rectangular shape, the incident face 143 is additionally provided. It is necessary to look at the lens 140 in which the furrow surface 141 is formed.

<Lens with a furrow on the entrance surface>

The overall configuration of the lens 140 in which the furrow surface 141 is formed on the incident surface 143 and the configuration of the illumination unit 100 including the lens 140 will be described first. FIG. 21 is a perspective view of a lens 140 in which an incident surface 143 is composed of a prism surface 142 and a furrow surface 141, and an emission surface 145 is a spherical lens shape. FIG. 22 is an incident surface 143. 23 is a plan view of the lens 140 including the prism face 142 and the furrow face 141, and the exit face 145 has a spherical lens shape, and FIG. 23 shows the incident face 143 having the prism face 142 and the furrow face ( 141 is a side cross-sectional view of the lens 140 having an exit surface 145 having a spherical lens shape, and FIG. 24 is a view showing an optical path of light emitted from the LED 120 of the lighting unit 100 of FIG. 1. .

1 and 21 to 23, a lens 140 is disposed on the light emitting unit 101. The lens 140 includes an entrance surface 143 and an exit surface 145, and a furrow surface 141 and a prism surface 142 are formed at the entrance side. A circular edge 144 is formed around the incident surface 143 of the lens 140. The lens 140 may be injection molded using a light transmissive material, and the material may be formed of a plastic material such as glass, poly methyl methacrylate (PMMA), polycarbonate (PC), or the like.

The incident surface 143 is perpendicular to the optical axis, the furrow surface 141 crosses the incident surface 143, and the furrow surface 141 passes through the center of the incident surface 143. 1 and 22, it can be seen that the furrow surface 141 is formed in an axis X direction perpendicular to the optical axis Z. A cross section of the furrow surface 141 cut into a plane (YZ plane) perpendicular to the longitudinal direction of the furrow surface 141 may have an arc shape, in addition to the shape of a part of a parabola, a hyperbola, and an ellipse. As a result, when the furrow surface 141 is viewed from the incident surface 143, when the cylinder is cut into a plane parallel to the longitudinal direction of the cylinder, the shape of the cut cylinder is taken. In addition, the width D4 of the furrow surface 141 may be formed to have a width of 9% to 40% of the incident surface diameter D6.

Prismatic surfaces 142 are formed on both sides of the furrow surface 141. Each unevenness forming the prism face 142 extends in the direction of an axis X perpendicular to the optical axis Z, and each unevenness is perpendicular to the longitudinal direction X of the furrow face 141. It is also arranged in order along the direction (-Y, + Y) also perpendicular to the optical axis Z. When the plurality of irregularities forming the prism surface 142 is cut into a plane YZ perpendicular to the longitudinal direction of the furrow surface 141, the cross section of each irregularities is a triangle. Both sides S1 and S2 of the triangular uneven pattern may have the same length or different angles.

In addition, the interval of each unevenness of the prism surface 142 may be a constant interval or may be formed to be densely formed in both directions (-Y axis, + Y axis). This degree of compaction may vary depending on the distribution of light.

The prism face 142 is disposed between the furrow face 141 and the edge 144. The prism face 142 is arranged in both directions perpendicular to the longitudinal direction of the furrow face 141, for example, left / right (-Y, + Y), thereby providing light distribution in the left / right (-Y, + Y) direction. You can increase it.

The emission surface 145 may reflect or refract the incident light to be emitted to the outside. The exit surface 145 may be formed of an aspherical lens or a spherical lens, and such aspherical lens or spherical lens shape may be selected in consideration of light distribution and illuminance distribution.

The reflected light, which is not emitted from the exit surface 145 to the outside, is converted into a light emission angle via at least one of the prism surface 142, the reflector 132, and the upper surface of the substrate 110, and thus the exit surface 145. ) Is transmitted.

Referring to FIG. 24, among the lights L1, L2, and L3 emitted from the LED 120 positioned at the outermost portion of the light emitting unit 110, L1 and L2 pass through the prism surface 142 and the emission surface 145. L3 is reflected from the prism face 142 of the lens 140, and in turn passes through the reflector 132, the prism face 142, the exit face 145, the prism face 142, and the like. Is changed and emitted through the exit surface 145.

Part of the light L4 emitted from the LED 120 in the center of the light emitting unit 110 is refracted and dispersed through the furrow surface 141 of the lens 140 and is emitted to the outside through the exit surface 145.

Since the structure of the lens 140 in which the furrow surface 141 is formed on the incident surface 143 and the illumination unit 100 including the lens 140 has been examined, the spatial light distribution and illuminance distribution in the following will be examined. Shall be.

FIG. 25 is a view showing spatial light distribution by the illumination unit 100 using the lens 140 of FIG. 21, and FIG. 26 is a view showing illuminance distribution by the illumination unit 100 using the lens 140 of FIG. 21. The figure shown. Referring to FIG. 25, the light distribution when the illumination unit 100 is viewed from the front in the X-axis direction is shown as B2, and the light distribution when the illumination unit 100 is viewed at the front in the Y-axis direction is as in B1. appear. The reason why B2 is more widely distributed than B1 is because light is diffused in the Y-axis direction by the prism face 142. However, unlike in FIG. 19, the lens 140 has a furrow surface 141 formed therein, so that the distribution of light in space is improved when viewed from the X and Y axes, respectively. That is, the distribution of light in the region around the optical axis Z is significantly larger than in FIG. 19. In addition, when viewed in the Y-axis direction (B1), the width is wider than in FIG. 19, more light is irradiated onto the irradiation surface, and when viewed in the X-axis direction (B2), compared to FIG. The formation of darker areas that are relatively darker than the irradiation surface is greatly reduced.

Referring to FIG. 26, when light is irradiated through the lens 140, the irradiated area of the surface on which the light is irradiated takes the shape of an approximate rectangle close to the rectangle. This shape is clearly different from the shape such as a dumbbell or ribbon as in FIG. As in FIG. 17, light is diffused in the Y-axis direction by the prism face 142, and light is irradiated so that the area around the X-axis is not dark is the effect by the furrow face 141. Compared to the lens 140 shown in FIG. 18, the furrow surface 141 additional to the lens of FIG. 21 serves as an illuminance enhancement surface that compensates for the illuminance at the center of the irradiation surface.

With reference to FIG. 23, the case where the emission surface 145 is made into the spherical lens or the aspherical lens is demonstrated in detail. Where h1 is the thickness of the prism face 142, h2 is the thickness of the edge 144, h3 is the thickness of the lens 140, D3 is the spacing between adjacent prisms, D4 is the width of the furrow face 141, and D6 is the edge. The width of the lens 140 excluding 144, r is the radius of curvature of the exit surface 145, S1 is one surface in the cross section of the prism surface 142, S2 is the other surface in the cross section of the prism surface 142. The equation representing the exit surface 145 in the shape of a spherical lens is as shown in Equation 1 below.

의 관계를 만족하며, z는 입사면(143)에서 출사면(145)까지의 높이, D6는 엣지(144)를 제외한 렌즈(140)의 폭, r은 출사면(145)의 곡률반경을 나타낸다. In Equation 1,

Z is the height from the incident surface 143 to the exit surface 145, D6 is the width of the lens 140 excluding the edge 144, and r is the radius of curvature of the exit surface 145. .

The expression representing the exit surface 145 of the conical curved lens shape is as shown in Equation 2 below.

의 관계를 만족하며, z는 입사면(143)에서 출사면(145)까지의 높이, D6는 엣지(144)를 제외한 렌즈(140)의 폭, r은 출사면(145)의 곡률반경, k는 원추계수(conic constant)를 나타낸다.In Equation 2,

Where z is the height from the incident surface 143 to the exit surface 145, D6 is the width of the lens 140 excluding the edge 144, r is the radius of curvature of the exit surface 145, k Denotes a conic constant.

The equation representing the exit surface 145 in the form of an aspherical lens is as shown in Equation 3 below.

은 비구면 계수값을 나타낸다.The symbol in <Equation 3> is the same as in <Formula 2>, and additionally

Denotes an aspherical coefficient value.

Any spherical or aspherical surface may be used as long as the exit surface 145 satisfies Equation (1), (2), and (Equation 3). In particular, in Equation 2, it depends on the value of the cone coefficient k, which is a sphere when k = 0, an ellipse when -1 <k <0, a parabola when k = -1, a hyperbola when k <-1, and k When> 0, it becomes a single spherical surface.

There are many cases where the exit surface 145 satisfies these equations, and a few examples will be given to examine the efficiency of the lighting unit according to each case. In order to examine the efficiency of the lighting unit 100, the simulation data using a computer program called FTE Calculator will be taken as an example. The purpose of the simulation with this computer program is to obtain the Energy Star certification and simultaneously the efficiency of the lighting unit 100. It is for verification. Therefore, below, the energy star certification and simulation data are examined.

<Energy star certification and review of light efficiency of irradiation surface>

Energy star refers to the national symbol of energy efficiency in the United States, and is a joint program of the US Department of Energy (EDO) and the Environmental Protection Agency (EPA), and is marked with the "ENERGY STAR" mark on products that meet the energy efficiency guidelines. It is a system to attach. ENERGY STAR certification can greatly contribute to improving the product's merchandise because the US consumers have a high preference for products that have earned the Energy Star mark, and there are merit about Energy Star mark-acquired products. .

Lighting devices that have been certified by Energy Star mean that you can use less power to illuminate the area you want to light with the required illuminance, which means you can reduce the number of lighting devices you need. Can be.

Since the lens 140 presented in the embodiment disclosed in connection with the present invention is a lens 140 that is generally used in the lighting unit 100 mounted to outdoor lighting such as street lamps and outdoor lights, Outdoor Area & Parking Garage must be satisfied. A computer program called FTE Calculator will be used to check whether this criterion is satisfied, and it will be apparent to those skilled in the art that the computer program can be easily obtained.

27 is a diagram illustrating the illuminance distribution of the irradiation surface according to the FTE Calculator.

Referring to FIG. 27, RT is a rectangular target, UP is a uniform pool, UR is a uniform rectangle, a sideward is an illuminance distribution in the + Y and -Y directions, a forward is an illuminance distribution in the + X direction, and a backward is an illuminance distribution in the -X direction. Indicates. The simulation data to be examined are all based on the illuminance distribution of the irradiation surface when the light source is at a height of 10 m. In FIG. 27, the widths of the gratings are all 10 m in width and width. For example, if the sideward is 2.5, it means that the illuminance distribution occurs in the space between 25m in the + Y direction and 25m in the -Y direction on the irradiation surface. Among the ENERGY STAR criteria, Unshielded is also used for the Outdoor Area & Parking Garage in Category A, and it is simulation data assuming that the Luminaire Output is about 9000 lumens (lm). The FTE (lm / W) value to be satisfied should be 53. Input power was measured at 120W. Among the embodiments, the Uniform Rectangle (UR) is wide, the ratio of the area of the Uniform Pool (UP) to the area of the Rectangular Target (RT) of the irradiation surface is high (hereinafter referred to as Covered), the Rectangular Target (RT) and the Uniform In both rectangular (UR), the wider the width of sideward, the more efficient lighting device. Hereinafter, the Covered will be described in detail. For example, it is assumed that the maximum illuminance value having the highest illuminance is 30 and the minimum illuminance value is 1 among the irradiation areas to which light emitted from the lighting device is irradiated. Where 30 and 1 represent the ratio of the two values, not the absolute values. Then, the area S1 where the illuminance value satisfies 1 or more and 30 or less is specified. When the average illuminance value in the region S1 specified above exceeds 6 which is 6 times the minimum illuminance value 1, the region having an illuminance value of 1 is excluded.

If the lowest illuminance value is 1.1 after excluding the region having an illuminance value of 1, the irradiation area is an area S2 where the illuminance value satisfies 1.1 or more and 30 or less. Again, it is determined whether the average illuminance value in S2 exceeds 6.6, which is 6 times the minimum illuminance value 1.1, and if it does not exceed 6.6, S2 is identified as a uniform pool (UP). If it exceeds 6.6, the above process is repeated until the average illuminance value does not exceed 6 times the minimum illuminance value to identify Sn as the Uniform Pool (UP). The rectangle surrounding Sn specified in this manner is called Rectangular Target (RT). After all, Covered represents a value of (UP / RT) * 100.

The simulation data were measured based on these assumptions and values, but the required FTE value, covered and efficient shape may vary depending on the use of the lighting device, installation height, input voltage, and output brightness. For example, the figures used in the simulations are exemplary, and in addition, the FTE calculator can measure based on the Unshielded type, and the required FTE values can be other figures such as 37, 48, and 70.

In each experiment, h1 is 1mm, h3 is 14.6mm, and D6 is 45mm. R is 24.64mm when the exit surface 145 is a spherical lens and r is 17mm when an aspheric lens is used. When the exit surface 145 is an aspherical surface, a cone coefficient corresponding to a hyperbolic curve is used, and the aspherical surface coefficient value is substantially only C ₄ , C ₆ , and C ₈ that are meaningful for determining the shape of the lens 140. Wherein C ₄ is -9.7407e ^-8, C ₆ is 4.1275e ^-8, C ₈ is -4.1969e ^- was tested by inserting a value of ^12.

In Experimental Example 1, the exit surface 145 has a spherical lens shape and there is no furrow surface 141, where Covered is 76%, FTE (lm / W) is 53, FTE (Rectangular Target) is 1.9, Sideward is 2.6, FTE (Uniform Target) is Forward and Backward is 0.9 and Sideward is 2.0.

In Experimental Example 2, the exit surface 145 has a spherical lens shape, the curvature radius of the furrow surface 141 is 5 mm, and the width of the furrow surface 141 is 8 mm, where Coverd is 84% and FTE (lm / W) is 58, FTE (Rectangular Target) Forward and Backward is 1.7, Sideward is 2.6, FTE (Uniform Target) Forward and Backward is 1.3 Sideward is 2.1.

In Experimental Example 3, the exit surface 145 has an aspherical lens shape, and there is no furrow surface 141, where Covered is 81%, FTE (lm / W) is 55, FTE (Rectangular Target) is 1.8, Sideward is 2.5, FTE (Uniform Target) is Forward and Backward is 0.9 and Sideward is 2.0.

In Experimental Example 4, the exit surface 145 has an aspherical lens shape, the curvature radius of the furrow surface 141 is 2 mm, and the width of the furrow surface 141 is 4 mm, wherein Coverd is 85% and FTE (lm / W) is 58, FTE (Rectangular Target) Forward and Backward is 1.7, Sideward is 2.5, FTE (Uniform Target) is Forward and Backward is 1.3 Sideward is 2.1.

In Experimental Example 5, the exit surface 145 has an aspherical lens shape, the curvature radius of the furrow surface 141 is 5 mm, and the width of the furrow surface 141 is 8 mm, wherein Coverd is 88% and FTE (lm / W) is 60, Forward and Backward of FTE (Rectangular Target) is 1.6, Sideward is 2.5, Uniform Target (FTE) is Forward and Backward is 1.3 and Sideward is 2.1.

In Experimental Example 6, the exit surface 145 has an aspherical lens shape, the curvature radius of the furrow surface 141 is 9.2 mm, and the width of the furrow surface 141 is 12 mm, wherein Coverd is 83% and FTE (lm / W). Is 57, Forward and Backward of FTE (Rectangular Target) is 1.6, Sideward is 2.4, Uniform Target (FTE) is Forward and Backward is 1.2 and Sideward is 2.0.

In Experimental Example 7, the exit surface 145 has an aspherical lens shape, the radius of curvature of the furrow surface 141 is 12 mm, and the width of the furrow surface 141 is 16 mm, where Covered is 89% and FTE (lm / W) is 61, Forward and Backward of FTE (Rectangular Target) is 1.4, Sideward is 2.1, Uniform Target (FTE) is Forward and Backward 1.2 and 1.2 Sideward is 1.7.

The experimental examples are shown in the following Table 1.

Curvature radius / width of the furrow
(mm) Exit face shape Minimum width in the X-axis direction of 10% of the maximum illuminance (m) Maximum width in the Y-axis direction of 10% of the maximum illuminance (m) Rectangular Target (FTE) Uniform Rectangle (FTE) Forward Sideward Backward Coverd (%) Forward Sideward Backward One none Spherical 10 22 1.9 2.6 1.9 76 0.9 2.0 0.9 2 5/8 Spherical 11 22 1.7 2.6 1.7 84 1.3 2.1 1.3 3 none Aspheric surface 10 23 1.8 2.5 1.8 81 0.9 2.0 0.9 4 2/4 Aspheric surface 12 23 1.7 2.5 1.7 85 1.3 2.1 1.3 5 5/8 Aspheric surface 12 23 1.6 2.5 1.6 88 1.3 2.1 1.3 6 9.2 / 12 Aspheric surface 14 23 1.6 2.4 1.6 83 1.2 2.0 1.2 7 12/16 Aspheric surface 15 20 1.4 2.1 1.4 89 1.2 1.7 1.2

FIG. 28 is a view showing spatial light distribution by the illumination unit 100 using the lens 140 of Experimental Example 5, and FIG. 29 is an illuminance distribution in the illumination unit 100 using the lens 140 of Experimental Example 5. The figure which shows. Referring to FIG. 28, the light distribution when the illumination unit 100 is viewed from the front in the X-axis direction is shown as B2, and the light distribution when the illumination unit 100 is viewed at the front in the Y-axis direction is shown as B1. appear. Referring to FIG. 29, it can be seen that the illuminance distribution in the Y-axis direction is much wider than that in the X-axis direction, and the illuminance distribution close to the rectangle is shown. 28 and 25 are the same as in FIG. 28 and FIG. 25, the lack of light in the central portion of the irradiation surface is not the same, but in FIG. 25, the light in the central portion is excessive compared to the boundary region of the light. It can be seen that light is not uniformly distributed over the entire irradiation surface. On the other hand, FIG. 28 shows that the light in the center portion of the irradiation surface is less than that in FIG. 25, and thus the illuminance distribution is uniformly distributed over the entire irradiation surface.

When the data values of Experimental Example 5 examined in FIG. 28, FIG. 29 and the above are combined, the most efficient case of the above Experimental Examples is Experimental Example 5. FIG. In Experimental Example 5, the sideward of the FTE (Rectangular Target) is 2.5, and the sideward of the Uniform Target (FTE) is 2.1, which is the highest value among the experimental cases. The top figure is 60. Therefore, it will be preferable to use the lens 140 having a value corresponding to Experimental Example 5.

However, there are various criteria for evaluating the efficiency of the lens 140, as discussed above, such as sideward width, Covered, FTE (lm / W) values, and Experimental Example 5 does not show an absolute advantage in all criteria. Therefore, when the actual lighting device is used, any one of the width of the sideward, Covered, TE (lm / W) value may be important, in this case, Experiment 2 and experiments specified in other experiments or above other than Experiment 5 Lenses 140 other than Examples 4 to 7 may exhibit better efficiency. However, in the case of the lighting unit 100 used in street lamps, outdoor lights, etc. among the outdoor lights, it has an exit surface 145 having a spherical or aspherical lens shape, and the prism surface 142 and the furrow surface 141 on the incident surface 143. Is formed, and the width of the furrow surface 141 is higher than the general lighting unit in that the lighting unit 100 having the lens 140 having a diameter of 9% to 40% of the incident side diameter of the lens 140 is higher than that of the general lighting unit. Obviously, it will be appreciated that all of the lenses 140 having this feature are within the scope of the present invention. In addition, the lens 140 of the present example and the equivalent lens 140 may be used in the lighting unit 100, which preferably exhibits an illuminance distribution close to a rectangle in applications other than a street lamp and an outdoor lamp.

<Embodiment of Illumination Unit Using a Lens having an Emission Surface Spherical or Aspherical Lens and Having an Furrow and a Prism Surface on the Incident Surface>

30 is a side sectional view showing a lighting unit 100A according to the second embodiment. In the description of the second embodiment, the same parts as in the first embodiment will be referred to the first embodiment, and redundant description thereof will be omitted.

Referring to FIG. 30, the lighting unit 100A includes a light emitting unit 101, a lens 140, and a gap member 130. The gap member 130 may be formed of an epoxy or silicone resin material and formed in a ring shape. The gap member 130 may be in contact with the edge of the upper surface of the substrate 110 of the light emitting part 101, and may be formed on the bottom surface of the edge 144 of the lens 140. Contact with Accordingly, the substrate 110 is positioned between the substrate 110 and the lens 140, and is spaced apart from the substrate 110 and the lens 140 at a predetermined interval G1. The space 105 formed by the gap member 130 may improve the light directivity distribution of the LED 120 of the light emitting unit 101.

On the other hand, a phosphor may be added to the gap member 130 if necessary. In addition, a reflective material may be coated on the upper surface of the substrate 110 of the light emitting unit 101 to reflect light traveling to the substrate 110.

31 is a side sectional view showing a lighting unit 100B according to the third embodiment. In the description of the third embodiment, the same parts as those of the first embodiment are referred to the first embodiment, and redundant description thereof will be omitted.

Referring to FIG. 31, in the illumination unit 100B, the edge 144A of the lens 140 protruding downward toward the light emitting unit 101 replaces the gap member 130. The edge 144A of the lens 140 may be disposed in contact with the top edge of the substrate 110 of the light emitting portion 101, or the top edge of the substrate 110 of the light emitting portion 101 and the substrate 110. All of the outer peripheral surface of the contact may be arranged.

The edge 144A of the lens 140 separates the substrate 110 of the light emitting unit 101 from the lens 140 at a predetermined interval G1.

The space 105 between the light emitting unit 101 and the lens 140 may be filled with a resin such as silicon or epoxy, and a phosphor may be added to the resin.

The substrate 110 of the light emitting unit 101 is disposed below the edge 144A of the lens 140, and the lens edge 144A is stepped with respect to the incident surface 143. As another example, a protrusion may be formed around an outer surface of the upper surface of the substrate 110 to maintain a distance from the lens 140.

32 is a side sectional view showing a lighting unit 100C according to the fourth embodiment. In the description of the fourth embodiment, the same parts as those in the first embodiment will be referred to the first embodiment, and redundant description thereof will be omitted.

Referring to FIG. 32, the reflective plate 155 is disposed on the substrate 110 of the light emitting unit 101 of the lighting unit 100C. The reflecting plate 155 is disposed to cover an area other than the LED 120 is exposed on the substrate 110 with the LED hole 155A so as not to cover the LED 120. Therefore, a part of the light emitted from the LED 120 can be reflected by the reflecting plate 155, thereby increasing the amount of reflected light, the light efficiency can be improved. The reflective plate 155 does not necessarily need to be a separate member from the substrate 110, and the upper surface of the substrate 110 may replace the reflective plate 155 by using the substrate 110 having a high reflectance on the upper surface. In addition, a diffusion agent may be applied to the upper surface of the reflective plate 155.

A gap member 153 is disposed between the substrate 110 and the edge 144 of the lens 140, and the gap member 153 is spaced apart from the substrate 110 by a predetermined interval G1. A space 105 is formed between the lens 140 and the substrate 110, and the light emitted from the LED 120 is dispersed in the space 105 between the substrate 110 and the lens 120 and is dispersed. Light may be dispersed through the prism face 142 and the furrow face 141 of the lens 140.

Meanwhile, the rest of the configuration is the same as that of the fourth embodiment of FIG. 32, and there is also a fifth embodiment (not shown) using the gap member 130 described in the first embodiment instead of the gap member 130 of the fourth embodiment. In the fifth embodiment, the reflection plate 155 used in the fourth embodiment is used to improve both the breakdown voltage characteristics and the light efficiency in the same manner as the gap member 130 described in the first embodiment. The light efficiency can be further improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications other than those described above are possible. For example, each component shown in detail in the embodiment of the present invention may be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

100: lighting unit
101: light emitting unit
130: gap member
140: Lens
141: furrow noodles
142: prism surface
143: incident surface
145: exit surface

Claims (21)

An incidence surface perpendicular to the optical axis, including a furrow surface crossing the surface and a prism surface formed on both sides of the furrow surface; And
An emission surface for refracting light incident through the entrance surface;
As a lens comprising,
And the cross section of the prism face is triangular when the lens is cut into a plane perpendicular to the longitudinal direction of the furrow face.
The method of claim 1,
The furrow surface is round, lens.
delete An incidence surface perpendicular to the optical axis, including a furrow surface crossing the surface and a prism surface formed on both sides of the furrow surface; And
An emission surface for refracting light incident through the entrance surface;
Including,
The width of the furrow surface is 9% to 40% of the diameter of the incident surface.
An incidence surface perpendicular to the optical axis, including a furrow surface crossing the surface and a prism surface formed on both sides of the furrow surface; And
An emission surface for refracting light incident through the entrance surface;
As a lens comprising,
When the light is irradiated through the lens, the shape of the irradiation area of the surface on which the light is shining is an approximate rectangle.
The method according to any one of claims 1, 2, 4 or 5,
The exit surface is spherical;
An incidence surface perpendicular to the optical axis, including a furrow surface crossing the surface and a prism surface formed on both sides of the furrow surface; And
An emission surface for refracting light incident through the entrance surface;
Including,
The exit surface is an aspherical lens.
In the lens comprising an entrance surface perpendicular to the optical axis and an exit surface for refracting the light incident through the entrance surface,
The incident surface includes a light diffusing surface for spreading light to the outside; And
An illuminance reinforcing surface that compensates for illuminance at the center of the irradiation surface and is formed in the longitudinal direction of the light diffusion surface passing through the center of the incident surface;
Including,
When the lens is cut into a plane perpendicular to the longitudinal direction of the illuminance enhancement surface, the cross section of the light diffusion surface is triangular.
The method of claim 8,
The roughness enhancing surface is a round shape.
delete In the lens comprising an entrance surface perpendicular to the optical axis and an exit surface for refracting the light incident through the entrance surface,
The incident surface includes a light diffusing surface for spreading light to the outside; And
An illuminance reinforcing surface that compensates for illuminance at the center of the irradiation surface and is formed in the longitudinal direction of the light diffusion surface passing through the center of the incident surface;
Including,
The width of the illuminance enhancement surface is 9% to 40% of the diameter of the incident surface.
In the lens comprising an entrance surface perpendicular to the optical axis and an exit surface for refracting the light incident through the entrance surface,
The incident surface includes a light diffusing surface for spreading light to the outside; And
An illuminance reinforcing surface that compensates for illuminance at the center of the irradiation surface and is formed in the longitudinal direction of the light diffusion surface passing through the center of the incident surface;
Including,
When the light is irradiated through the lens, the shape of the irradiation area of the surface on which the light is shining is an approximate rectangle.
The method according to any one of claims 8, 9, 11 or 12,
The exit surface is spherical;
In the lens comprising an entrance surface perpendicular to the optical axis and an exit surface for refracting the light incident through the entrance surface,
The incident surface includes a light diffusing surface for spreading light to the outside; And
An illuminance reinforcing surface that compensates for illuminance at the center of the irradiation surface and is formed in the longitudinal direction of the light diffusion surface passing through the center of the incident surface;
Including,
The exit surface is an aspherical lens.
An entrance plane perpendicular to the optical axis; And an emission surface for refracting and exiting light incident through the entrance surface.
The irradiation area on the surface illuminated by the light emitted from the lens forms an approximate rectangle, the length of the long side of the approximate rectangle being 2.5 times the height from the light source to the irradiation surface, and the length of the short side of the approximate rectangle from the light source to the irradiation surface Lens with a height of 1.6 times and a UP / RT of 0.88.
16. The method of claim 15,
The incidence surface comprises a furrow surface across the incidence surface,
The furrow surface is round, lens.
16. The method of claim 15,
The incident surface includes a furrow surface crossing the incident surface and a prism surface formed on both sides of the furrow surface,
And the cross section of the prism face is triangular when the lens is cut into a plane perpendicular to the longitudinal direction of the furrow face.
16. The method of claim 15,
The incidence surface comprises a furrow surface across the incidence surface,
The width of the furrow surface is 9% to 40% of the diameter of the incident surface.
16. The method of claim 15,
When the light is irradiated through the lens, the shape of the irradiation area of the surface on which the light is shining is an approximate rectangle.
The method according to any one of claims 15 to 19,
The exit surface is spherical;
The method according to any one of claims 15 to 19,
The exit surface is an aspherical lens.

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