KR101612276B1 - Condensing device for lighting and manufacture method thereof - Google Patents

Abstract

Provided are a light condensing device for lighting and a method of manufacturing the same. The light condensing device includes a light condensing lens which has top and bottom surfaces with circular shapes and has a conical shape so that a diameter thereof is gradually reduced toward a lower part thereof. A cavity, through which a portion of the light radiated from a light source transmits and which has an incident surface upon which light radiated from the light source is incident, is provided in the central portion of the light condensing lens. A front surface formed on a side surface of the light condensing lens is formed in a curved shape having straight line surfaces having mutually different angles. The light which is radiated from the light source and is primarily reflected upon the incident surface is totally reflected to be radiated in parallel to an optical axis through a light emitting surface formed on a top surface of the light condensing lens and another portion of the light radiated from the light source is radiated through the cavity. Thus, the cavity is formed on the central portion of the light condensing lens so that the light is directly transmitted without passing through the light condensing lens, thereby improving light condensing efficiency.

Description

TECHNICAL FIELD [0001] The present invention relates to a condensing device for illumination,

The present invention relates to a light concentrating device for illumination and a method of manufacturing the same, and more particularly, to a light concentrating device for illumination that concentrates light emitted from a light source of a high power illumination to which a plurality of LEDs are applied, and a manufacturing method thereof.

As the depletion of fossil energies and environmental problems are emerging, alternative energy for energy saving is developed all over the world and energy saving technology development activities are being promoted.

In general, with the use of mercury or the like in conventional lighting apparatuses, the government is focusing on the LED (light emitting diode) lighting industry in order to improve environmental problems and improve power saving efficiency.

LEDs have advantages such as fast response speed, low power consumption and long lifetime as they emit light generated by the recombination of the small number carriers (electrons or holes) injected using the PN junction structure of semiconductors have.

For example, the LED consumes about 1/10 of the power consumption of conventional incandescent bulbs and halogen bulbs, which can greatly reduce electric energy.

In general, the LED used has been used mainly for investigating a wide range of light because the light emitting angle of the illuminating light is very large.

Meanwhile, recently, when an LED is used to investigate a local area at a long distance, a condensed light value for condensing the light irradiated by the LED has been developed as an etendue problem has occurred.

For example, Patent Literatures 1 to 3 below disclose condenser lens technology for LED illumination according to the prior art.

Conventionally used primary condenser lenses are formed as convex aspheric lens surfaces whose upper surfaces are convex, and lower surfaces are formed flat, and light condensing efficiency in the vicinity of the optical axis is somewhat improved by the aspherical lens surface.

However, in the primary focusing lens, the light collecting efficiency is improved only locally in the vicinity of the optical axis, and the light is refracted in the outward direction far away from the optical axis and diffused in the far edge region.

In order to solve this problem, the condenser for LED illumination uses a secondary condenser lens.

For example, Fig. 1 is a sectional view of a secondary condenser lens for LED illumination according to the prior art.

The condensing lens 1 for LED illumination according to the related art includes a first lens portion 2 of a transparent body and a second lens portion 3 surrounding the first lens portion 2.

The first lens unit 2 has convex first and second aspherical lens surfaces 4 and 5 having different sizes on the symmetrical surface.

The second lens unit 3 is formed of an incident surface 7 protruding from the outer periphery of the second aspherical surface 5 and inserted with the LED 6 and refracted by the light irradiated from the LED 6, A reflecting surface 8 extending obliquely to a convex curved surface gradually becoming wider from the surface 7 to the second aspherical surface 5 and reflecting the light of the LED 6 and a reflecting surface 8 reflecting the light of the first aspherical surface And an exit surface 9 extending obliquely to the curved surface concave toward the surface 4 and refracting the light of the totally reflected LED 6 into light parallel to the optical axis X and emitting the light.

Korean Patent Registration No. 10-0756174 (issued on September 5, 2007) Korean Patent Publication No. 10-2014-0124270 (published on October 24, 2014) Korean Patent Publication No. 10-2014-0104716 (published on August 29, 2014)

However, the secondary focusing lens according to the related art covers the LES (Luminous Emitting Surface) portion of the light source of the LED light source to adjust the direction of the light.

Here, the light collection efficiency of the condenser lens is determined by the transmittance, the refractive index, and the size of the material.

Accordingly, when the condensing lens according to the related art is used in a lighting apparatus, the light emitted from the light source is less than the light amount of the light source in the process of being reflected, refracted and absorbed by the incident surface, The efficiency is lowered.

In recent years, COB (Chip On Board) LED products, which are high output light sources, have been developed in low power LEDs, which are low power light sources. However, compared to the development of active LED light source technology, there is very little optical lens business related industry.

Also, since the COB light source is not standardized, the development of the COB high-heat-resistant lens technology for controlling the direction of the light emitted from the LED, that is, the light distribution, is slow

That is, in the case of a lens manufactured using a conventional injection process, it takes several months from the time of designing, assembling, and manufacturing the mold, and it requires an investment cost of several tens of thousands of won or more depending on the lens size, cavity number, and precision.

Therefore, it is absolutely necessary to develop alternatives that can cope with the development of rapidly changing LED lighting products, and that can develop low cost and short delivery time when developing lens components.

SUMMARY OF THE INVENTION An object of the present invention is to provide an illumination condensing device capable of improving light collection efficiency of light emitted from a high-power LED light source.

Another object of the present invention is to provide a condensing device for illumination capable of adjusting the light distribution angle of the condensing lens by adjusting the height of the condensing lens and the cavity, and a method of manufacturing the same.

According to an aspect of the present invention, there is provided an illumination light concentrating apparatus including a light collecting lens formed in a conical cylindrical shape having a top surface and a bottom surface each having a circular shape and a diameter decreasing toward the bottom, Wherein the cavity has a cavity through which a part of the light emitted from the light source is transmitted and an incident surface through which the light emitted from the light source is incident is provided on the outer circumferential surface, And the light refracted at the incidence surface is totally reflected so as to exit in parallel with the optical axis through the exit surface formed on the upper surface of the condenser lens, And a part of the light is emitted through the cavity.

According to another aspect of the present invention, there is provided a method of manufacturing a light condensing device for illumination, comprising: (a) forming a liquid at a room temperature, which is injected into an injection space formed in one mold, (B) injecting the liquid material into the injection space of the mold by the injection amount calculated in the step (a); and (c) heating and curing the liquid material injected into the mold And a cavity in which a part of light irradiated from the light source is transmitted through the center of the condensing lens and an incident surface through which light irradiated from the light source is incident is formed on an outer circumferential surface of the cavity, Wherein a light refracted at the incidence surface is irradiated onto the side surface of the condenser lens, To total reflection through the surface parallel to the emission optical axis it is characterized in that each total reflection surface is formed in a curved surface having a plurality of straight surfaces of different angles.

As described above, according to the light condensing device for illumination and the method of manufacturing the same according to the present invention, it is possible to form a cavity in the center of the condensing lens and directly transmit the light emitted from the light source without passing through the condensing lens, Effect is obtained.

Particularly, according to the present invention, the total reflection surface of the condensing lens is formed into a curved surface having a plurality of straight lines at different angles according to the design process, whereby the light emitted from the light source is totally reflected to the emission surface, It is possible to obtain an effect of improving the efficiency of the semiconductor device.

Thus, according to the present invention, ray tracing is easy, and the effect of expanding to various design rules freely is obtained.

In other words, according to the present invention, it is possible to produce various types of condensing lenses capable of simultaneously forming condensing lenses of various light distribution angles at the same time, and it is possible to minimize the development period of the condensing lens and reduce the initial investment cost by 90% or more Loses.

In addition, according to the present invention, it is possible to achieve an efficiency of 96% or more which can not be realized by using a material made of a plastic material, which is made of a silicon material having high heat resistance and reliability, %, And the manufacturing cost of the product can be reduced.

According to the present invention, the condensing lens of various light distribution angles can be manufactured by adjusting the height of the condensing lens by changing the injection amount of the liquid material supplied to one mold and adjusting the height of the cavity formed in the condensing lens Effect is obtained.

Thus, according to the present invention, there is no need to produce a separate mold for adjusting the light distribution angle, so that it is possible to reduce the manufacturing cost of the product and improve the workability of the manufacturing work.

According to the present invention, it is not necessary to design a mold having various shapes and sizes by using a dispensing method of injecting a liquid material having a predetermined amount for each light distribution angle to be manufactured into a mold, An effect that can be applied is obtained.

1 is a cross-sectional view of a secondary condenser lens for LED illumination according to the prior art,
2 is a perspective view of a light condensing device for illumination according to a preferred embodiment of the present invention,
FIG. 3 is a cross-sectional view of the condensing device shown in FIG. 2,
4 is a view for explaining Snell's law,
5A and 5B are diagrams for explaining the designing process of the total reflection surface,
6 is a diagram illustrating a light distribution curve of a COB type light source,
FIG. 7 is an example of a light distribution table in which one million light beams are input for computer simulation,
8 is a diagram illustrating a transition of a light distribution angle realized by reducing the initial designed condensing lens height in units of 10%
9 is a graph showing an efficiency change according to the height of the condenser lens,
10 is a graph showing a change in illumination efficiency according to the height of the condenser lens 20,
Figure 11 is an illustration of an individual ray tracing result of a condensing lens having a height of 20%
12 is a graph showing the quality characteristics according to the height of the condensing lens,
13 is a schematic view of a condenser lens according to a change in the height variation of the cavity,
FIG. 14 is a graph showing the light distribution angle and illumination efficiency according to the height of the cavity of the condenser lens,
FIG. 15 is a process diagram for explaining a step-by-step description of a method for manufacturing an illumination condensing apparatus according to a preferred embodiment of the present invention,
16 is an exemplary view of a mold used in manufacturing a condenser lens,
17 is an illustration of an illumination condensing apparatus according to another embodiment of the present invention,
Figs. 18 and 19 are exemplary views of a light condensing device for illumination according to another embodiment of the present invention, respectively. Fig.

A light condensing device for illumination according to a preferred embodiment and a method of manufacturing the same will be described in detail with reference to the accompanying drawings.

FIG. 2 is a perspective view of a light focusing device for illumination according to a preferred embodiment of the present invention, and FIG. 3 is a sectional view of the light focusing device shown in FIG.

As shown in FIGS. 2 and 3, the focusing device for illumination according to the preferred embodiment of the present invention is provided with a condenser lens 20, which is formed in a substantially conical shape having a top surface and a bottom surface that are flat and whose diameter decreases toward the bottom, A light source 11 is provided under the condenser lens 20.

In the present embodiment, the light source 11 may be provided as a high-power surface light source of 5 W or more mounted on a circuit board by a plurality of LEDs in a COB (Chip On Board) manner.

Therefore, the present invention concentrates the light emitted from the light source and locally illuminates the far distance.

A region where light is emitted from a light source of a COB system is defined as a luminescent surface area 12 and a light source of different power consumption is manufactured by changing the size (radius) of the light emitting surface region 12 .

When the condenser lens 20 is applied to the COB type light source 11, the condenser lens 20 may be designed to fit the size of the light-emitting surface region 12 or be designed to fit the substrate size, The size of the light-collecting surface region 12 may be set to correspond to the size of the light-collecting surface 20 in the example.

The position of the condenser lens 20 is designed by fixing the size of the dam including the light emitting surface area 12 to the inner diameter of the condenser lens 20.

Meanwhile, the light pattern emitted from the COB-type light source 11 must be set as a variable. However, manufacturing techniques and materials are different for each manufacturer, and the light distribution angle is actually various.

The LED is theoretically Lambertian, and when it is discussed in terms of the light distribution angle, FWHM (Full Width at Half Maximun) is defined as 120 degrees, while the actual product is measured from about 105 degrees to about 118 degrees, The light distribution angle is defined as Lambertian light distribution (120 degrees).

The side surface of the condensing lens 20 may be formed in a shape of a rotating body in which a plurality of linear surfaces having different angles are connected and rotated by the angle of light emitted from the light source 11.

Generally, in the design of the condenser lens 20, considerably complicated and difficult theories are used according to the theory of wave theory and graininess, but in the present embodiment, the condenser lens 20 is designed using Snell's law .

For example, FIG. 4 is a diagram illustrating Snell's law.

As shown in FIG. 4 (a), Snell's law is that when light propagates through a medium having a refractive index n1 that is tight in a medium having a refractive index n2, when light passes through the interface between the two media It is the law that defines the rule of refraction.

This can be expressed by Equation (1).

Here, the dense medium will reflect the refractive index of the lens material, and the coherent medium is atmospheric, so that the refractive index becomes the refractive index of air, that is,

Reflecting this in Equation 1, sin? 1 = n2 * sin? 2.

Using this Snell's law, it is possible to calculate the refraction angle when light incident at a certain angle passes through an interface having a different refractive index.

Here, when the incident angle of the light becomes larger than a certain angle, the light is reflected back to the inside without passing through the boundary, which is defined as total internal reflection (TIR).

When the refraction angle is 90 degrees in Equation (1), as shown in FIG. 4 (b), the light is refracted to the boundary without advancing to the air layer.

Here, if the angle of incidence with respect to the refracting angle going to the interface is defined as a critical angle c, sin90 = n2 * sin? 2, i.e., sin (? C) is 1 / n2.

For example, the critical angle between a material with a refractive index of 1.5 and air is about 41.81 degrees. If the angle of incidence is greater than the critical angle, the light does not advance to the outside and proceeds inside.

The light incident at an angle larger than the critical angle is reflected at the same angle with respect to the normal of the interface according to the internal reflection rule.

The cavity 21 may be formed at the center of the condenser lens 20 with a diameter slightly larger than the light emitting surface area 12 of the light source 11 provided below the condenser lens 20.

Here, the diameter of the cavity 21 may be formed at the outermost size of the dam surface that protects the light emitting surface region 12 of the light source 11.

For example, the cavity 21 may be formed to have a diameter which is larger by about 5 mm or less than the light-emitting surface region 12.

The cavity 21 functions to transmit a part of light irradiated from the light source 11 directly without passing through the condenser lens 20.

In this embodiment, the bottom surface width of the condenser lens 20 may be set to a predetermined set value, for example, about 1 mm.

Generally, a condenser lens is manufactured using a synthetic resin material such as polycarbonate and PMMA (Polymethylmethacrylate) or glass suitable for an injection process.

Since the condenser lens made of a synthetic resin material has a low heat-resistant temperature, the production temperature of the condenser lens is limited to -30 ° C to 75 ° C. This is to prevent the deformation of the condenser lens due to heat generated in the light source and transmitted to the condenser lens in the case of the thermoplastic resin and accelerate the degradation due to heat to prevent yellowing and mechanical deformation of the material.

On the other hand, there are various materials such as glass or silicone for the high heat-resistant material, but in the case of glass, since the melting point is about 1200 ° C or higher, there has been a problem that a facility for heating to a high temperature has to be provided.

On the other hand, silicon is a thermosetting resin that is in a liquid state at room temperature, protects chips and gold wires during the manufacture of LEDs, and has excellent optical properties. Therefore, silicon is widely used as an encapsulant material, It is also proven.

Accordingly, in this embodiment, the condenser lens 20 is manufactured using silicon for simplification of the process.

These silicon materials have various products according to their purposes but they are generally used due to the relatively economical efficiency of methyl-based silicon having a refractive index of 1.4. Some low-power LEDs have a refractive index of 1.5 Phenyl-based silicon is used, but yellowing phenomenon due to the use of phenyl-based silicon has been reported, which is disadvantageous in that it is expensive.

Accordingly, in this embodiment, the condenser lens 20 is manufactured using methyl-based silicon having a refractive index of 1.41.

The condensing lens 20 has quality characteristics such as FWHM, lens efficiency, and illumination efficiency.

Wherein the FWHM is an angle of two points at a position that is 50% of the maximum luminous intensity on the light distribution curve, the lens efficiency is an efficiency (Total Lumen) from the condensing lens, (Downward Lumen).

The quality characteristics of the condenser lens 200 can be analyzed by computer simulation using an optical simulator.

2, an incident surface 22 on which light irradiated by the light source 11 is incident is formed on the outer circumferential surface of the cavity 21, and an incident surface 22 is formed on the side surface of the collecting lens 20, The incident surface 24 is formed on the upper surface of the condenser lens 20 so that the incident light is refracted and reflected by the condenser lens 20 to be emitted therefrom.

The total reflection plane 23 may have a plurality of linear planes starting at a bottom surface width and having different angles so as to be totally reflected depending on the outgoing angle of the light emitted from the light source.

5A and 5B are diagrams for explaining the designing process of the total reflection surface.

5A, the diameter of the light-emitting surface region 12 of the COB-type light source 11 is about 12 mm, the width of the dam is about 1 mm, the thickness of the light-emitting surface region 12 is about 0.55 mm , A line parallel to the optical axis (the vertical line of the center of the COB type light source) is drawn to constitute the inner side surface of the condenser lens 12 as shown in FIG. 5A (B) A line having a length of 1 mm is drawn at which the total reflection plane 23 starts.

Then, as shown in (c) of FIG. 5 (a), light is emitted from the center of the light source 11 at 10 degrees to the incident surface 22.

Here, the light reaching the incident surface 22 is refracted into the condenser lens 20 by Snell's law, and the refracted angle? Is about 7.07 degrees because 1 * sin10 = 1.41 * sin ?.

Next, for the formation of the total reflection plane 23, a line having an arbitrary angle on the bottom surface of the condenser lens 20 is schematically illustrated as shown in (D) of Fig. 5A. Here, the first refracted ray end shown in FIG. 5A (d) is drawn so as to meet.

The arbitrary angle is required to be larger than about 45.59 degrees, which is a critical angle between air (n = 1) and silicon (n = 1.41), to cause internal reflection.

Therefore, as shown in FIG. 5A (e), a vertical line to an arbitrary line is plotted at a point where a light ray intersects with an arbitrary line, and reflection is reflected at the same angle by the principle of reflection at a point, do.

That is, when an arbitrary line is drawn at an angle of about 46 degrees, the light totally reflected is totally reflected at about 5.07 degrees (84.93 degrees in the plane) on the optical axis.

Subsequently, as shown in (bar) of FIG. 5A, an angle value arbitrarily set so that the angle of the light emitted from the total reflection surface 23 becomes parallel to the optical axis, that is, 0 degrees, is changed, The total reflection surface 23 is completed so as to proceed parallel to the optical axis.

Here, when the angle of the total reflection surface 23 is about 48.54 degrees, the light emitted from the light source 11 at an output angle of about 10 degrees travels in parallel with the optical axis.

5B, the light emitted from the light source 11 at an output angle of 20 degrees is subjected to the above-described process, and the light emitted from the COB type light source 11 Thereby completing the total reflection surface 23.

Here, the light emitted from the light source 11 at an exit angle of 20 degrees is refracted at about 14.04 degrees on the incident surface 22, and when the angle of the total reflection surface 23 is about 52.02 degrees, it goes parallel to the optical axis.

Thereafter, as shown in (A) of FIG. 5B, the respective total reflection surfaces are drawn at intervals of 10 degrees from an emission angle of 30 degrees to an angle of 80 degrees.

Table 1 is an angle table for primary refraction angle and total internal reflection.

Exposure angle 1st incidence angle of incidence Total slope angle 10 degrees 7.07 degrees 48.54 degrees 20 degrees 14.04 degrees 52.02 degrees 30 degrees 20.77 degrees 55.39 degrees 40 degrees 27.12 degrees 58.56 degrees 50 degrees 32.91 degrees 61.46 degrees 60 degrees 37.89 degrees 63.95 degrees 70 degrees 41.79 degrees 65.90 degrees 80 degrees 43.30 degrees 66.65 degrees

Through the above process, the total reflection angle is measured at an interval of 10 degrees with respect to the total exit angle from 10 to 80 degrees, and the exit angle is set at 80 degrees from the exit angle of the exit angle, Connect the points of contact with the incidence plane to complete the lens diagram of the focusing lens.

When the optical axis is rotated in the completed sectional view, the condenser lens 20 as shown in Fig. 5B is completed.

Meanwhile, the condenser lenses 20 designed according to the above process are designed to have straight lines at different angles at intervals of 10 degrees.

As described above, according to the present invention, since the total reflection plane is formed by a curved surface having a plurality of straight lines by applying a straight line instead of a curved line, ray tracing is easy and can be freely extended to various design rules.

It is needless to say that the present invention is not necessarily limited thereto and that the actual light source may uniformly irradiate light over the entire light output angle, May be changed so as to form curved surfaces having different curvatures by connecting curves of values.

That is, the total reflection surface 23 of the condensing lens 20 may be formed into a parabolic curved surface whose inclination angle with respect to the bottom surface increases from the lower portion to the upper portion.

As described above, according to the present invention, since the total reflection surface is designed with respect to the light emitted from the COB type light source at an output angle of 0 degree to 80 degrees, the light emitted from 80 degrees to 90 degrees will proceed as it is.

Therefore, the light distribution angle of the condenser lens 20 can be predicted around 10 degrees. On the other hand, the efficiency of the condenser lens 20 is analyzed using an optical simulator for accurate transmission of the material and prediction of an accurate result as much as the number of rays must be analyzed for the illumination efficiency analysis.

First, as shown in (a) of FIG. 5A, the light source 11 including the light emitting surface region 12 and the dam is approximately 12 mm.

The light source 11 is provided with a surface light source that inputs a total light amount of 100 lm through the light emitting surface region 12 and follows a Lambertian distribution and the surface of the dam and the surface of the COB substrate has inherent optical characteristics, One million beams were applied.

6 is a diagram illustrating a light distribution curve of a COB type light source, and Table 2 is a characteristic table of modeled COBs.

Quality characteristics Modeling characteristics Light distribution angle 120 degrees Lens efficiency 99.99% Lighting efficiency 99.99%

The condensed lens designed on the modeled COB can be placed and simulated.

Since the efficiency of the condensing lens 20 is predicted by inputting various optical characteristics of the actual material, the characteristics of the actual product manufactured using the silicon are applied in this embodiment.

7 is an exemplary view of a light distribution table in which one million rays are input for computer simulation, and Table 3 is a specification table of a condenser lens.

Evaluation items prediction Computer simulation Light distribution angle Around 10 degrees 9.6 degrees Lens efficiency - 92.3% Lighting efficiency - 90.3%

As expected, the light distribution angle of the actually designed condenser lens 20 was less than 10 degrees, and the lens efficiency and illumination efficiency were about 92.3% and 90.3%, respectively.

Meanwhile, the reference of the condenser lens 20 designed in this embodiment is a lens design according to the emission angle, and up to now, it has been designed based on light from 10 to 80 degrees with respect to the optical axis.

Therefore, in this embodiment, for the implementation of various light distribution angles, the light distribution angle realized when the height of the first designed condenser lens is set to 100% and the height thereof is reduced by 10% unit is simulated.

FIG. 8 is a diagram illustrating a transition of the light distribution angle realized by reducing the initial designed condensing lens height in units of 10%.

As shown in FIG. 8, the range of the light distribution angle, which can be realized by changing the height of the condenser lens, is considered to be about 10 degrees to 90 degrees, and it is also confirmed that the same range appears in products having different light emission areas.

And, when the height of the condensing lens is about 10% or less, it can be seen that the light distribution angle according to the height change changes considerably sensitively.

In addition, since the graph of the light distribution angle according to the height of the light collecting lens appears in the form of a log scale function, the light distribution angle expected by the height of the light collecting lens 20 can be estimated.

From the above results, the regression equation of the following equation (2) can be obtained by performing regression analysis on the basis of the present invention.

As a result of the validity test on Equation (2), it was confirmed that about 99% or more is valid.

On the other hand, the efficiency of the condenser lens is determined by the transmittance of the material. That is, it can be predicted that the higher the height of the condensing lens is, the lower the efficiency, and the regression analysis results are the same.

9 is a graph of efficiency change with height of the condenser lens.

In FIG. 9, when the height of the condensing lens is about 80% or less, the efficiency becomes about 95% or more, and since the trend also shows the type of the first-order equation, an effective regression equation as shown in the following Equation 3 can be obtained.

As a result of the accuracy verification of Equation (3), it is confirmed that more than 97% is valid.

10 is a graph of the illumination efficiency change according to the height of the condenser lens 20. FIG.

In this embodiment, the efficiency at which the light should actually be illuminated, that is, the light traveling downward of the condenser lens 20, is defined as the illumination efficiency.

In FIG. 10, the lower the height of the condensing lens 20, the lower the illumination efficiency of the product.

In order to analyze the cause, for example, ray tracing of the result of computational simulation of the condenser lens 20 designed to have a height of 20% was performed.

11 is an exemplary view of individual ray tracing results of a condensing lens having a height of 20%.

11, the light emitted from the light source 11 and reaching the total reflection surface 23 travels downward of the illumination, but the light reaching the emission surface 24 without passing through the total reflection surface 23 It can be seen that the actual exit surface 24 again reflects upward of the condenser lens 20 as a function of the total reflection surface. That is, after the light irradiated from the light source 11 is first refracted by the incident surface 22, all the light that can not reach the total reflection surface 23 is totally reflected by the exit surface 24, and the illumination efficiency is lowered.

Therefore, it is not necessary to consider it in a product in which efficiency is not so important, but efficiency is a very important factor in the case of a lighting device, so it is necessary to take measures against such a problem.

FIG. 12 is a graph of a quality characteristic according to the height of the condenser lens, and FIG. 13 is a schematic view of the condenser lens according to a change in the height variation of the cavity.

In the case of the condenser lens 20 in which the cavity 21 is formed at the central portion, the light distribution angle and the lens efficiency can be predicted, and the desired product can be realized through the above regression equation.

On the other hand, in order to improve the illumination efficiency, the upper surface of the condenser lens 20, that is, the exit surface 24 should be designed not to be a total reflection surface.

In this embodiment, as shown in FIG. 12, the height of the cavity 21 is lowered to 10% based on 100%, and further reflected as a design parameter to understand a change in the quality characteristic according to the height of the cavity 21 .

13A to 13C illustrate a condenser lens 20 in which the height of the cavity 21 is 100%, 70%, and 10%, respectively.

That is, in this embodiment, the height of the condenser lens 20 is 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10% And the height of the cavity 21 was increased from about 10% to about 100% with respect to the height of each condenser lens 20 by 10%.

Accordingly, total computational simulation was performed 120 times, and the result is shown in FIG.

14 is a graph of the light distribution angle and illumination efficiency according to the lens height according to the cavity height of the condenser lens.

14, even if the height of the cavity 21 is reduced from about 100% to about 50%, the change in the light distribution angle FWHM is insignificant, but when it is lower than about 50% of the height of the condenser lens 20 It can be seen that the light distribution angle changes.

For example, when the light distribution angle is about 9 degrees but the height of the cavity 21 is about 10% of the height of the condenser lens 20 when the height of the condenser lens 20 is 100% It is found that it increases by about 33 degrees.

As the height of the condenser lens 20 is lowered, the light distribution angle is considerably changed with respect to the height variation of the cavity 21. However, as the height of the condenser lens 20 is changed, .

Therefore, in order to make a desired angle in FIG. 14, the height of the condensing lens can be variously selected, and the height of the cavity at the height can be set.

In addition, it is understood that the illumination efficiency is improved as the height of the cavity 21 is lowered. That is, in order to achieve an efficiency of about 95% or more, it is understood that the height of the cavity 21 should be set to about 55% or less of the height of the condenser lens 20.

As described above, according to the present invention, the condenser lens is designed on the basis of the design process as described above to adjust the height of the condenser lens and the height of the cavity so that condenser lenses of various light distribution angles ranging from about 10 degrees to about 120 degrees can be manufactured , And the illumination efficiency can also be improved.

In particular, according to the present invention, the condensing lens having various light distribution angles can be manufactured by adjusting the height of the condensing lens by adjusting the injection amount of the liquid material injected into the mold to adjust the height of the condensing lens using one mold.

Next, a method for manufacturing an illumination condensing device according to a preferred embodiment of the present invention will be described in detail with reference to FIG.

FIG. 15 is a process diagram for explaining steps of a method for manufacturing an illumination condensing apparatus according to a preferred embodiment of the present invention.

Generally, a condenser lens for an LED light source is manufactured by an injection method.

For example, the condensing lens according to the related art is made of a plastic material such as polycarbonate or PMMA at a level of pellet or powder, heated to about 300 ° C or higher to be liquid, and then injected into the mold .

That is, when the plastic is used as a raw material, the condensing lens according to the related art supplies raw material to a melting zone, transfers the molten material in a liquid state by transfer, and injects the molten material into a cold mold at a high pressure do.

Therefore, the material injected into the mold is hardened due to the cold temperature of the mold and finished with the finished product.

Such a method for manufacturing a condensing lens according to the related art requires a separate working environment and safety education as a technology suitable for mass production of products, or a technology requiring high-temperature and high-pressure, mold movement, and pressing equipment.

Particularly, in order to manufacture a mold used for manufacturing a condensing lens, a variety of processing steps such as surface condition and heat treatment must be performed. Therefore, a considerable amount of time, effort, and infrastructure are required until a single product is produced.

Accordingly, it usually takes about two months or more from cavity fabrication to mold assembly.

In order to eliminate the problems of the method of manufacturing the condensing lens according to the prior art and to utilize the advantages of the conventional method, the raw material itself is made of silicon in liquid state at room temperature so as to remove the melting process using the high- .

The present invention uses a dispensing method in which a device for injecting a molten liquid material into a mold at high temperature is removed and a certain amount is directly injected into a mold through a syringe. Instead of melting the raw material and curing the material in a cold mold The liquid material is thermally cured to produce a condenser lens.

More specifically, the height of the condensing lens 20 corresponding to the light distribution angle of the condensing lens 20 to be manufactured is selected using the design process described above in step S10 of FIG. 15, and the height of the condensing lens 20 The injection amount of the liquid material according to the height is calculated.

The liquid material may be made of a material having transparency such as silicon or epoxy to allow light to pass therethrough and having heat resistance to withstand the heat generated from the light source.

In the present embodiment, it is preferable that the liquid material is provided as a material capable of maintaining the same thermal characteristics even at a temperature of about 120 캜.

A mold corresponding to the shape of the condenser lens 20 to be manufactured is manufactured in step S12.

At this time, the height of the cavity 21 corresponding to the light distribution angle of the condensing lens 20 is selected and the height of the cylindrical portion 16 formed on the mold 13 is adjusted according to the height of the selected cavity 21, do.

For example, FIG. 16 is an illustration of a mold used for manufacturing a condensing lens.

Fig. 16 (a) is a perspective view of the mold 13, and Fig. 16 (b) is a cross-sectional view of the mold 13. As shown in Fig.

As shown in FIG. 16, an injection space 14 corresponding to the shape of the condenser lens 20 to be manufactured may be formed in the mold 13.

The mold 13 in the present embodiment has the cavity 21 of the condenser lens 20 on the upper surface so that the manufactured condenser lens 20 can be easily demolded after the condenser lens 20 is manufactured. A lower mold 15 in which a cylindrical portion 16 having a shape corresponding to the lower mold 15 is formed and an upper mold 17 detachably coupled to the upper portion of the lower mold 15.

Accordingly, the present invention can easily demould a condenser lens manufactured by separating an upper mold and a lower mold after manufacturing a condenser lens by combining a lower mold and an upper mold.

The cylindrical portion 16 may be formed at different heights depending on the height of the cavity 21 of the condenser lens 20 to be manufactured.

Accordingly, the height of the cavity can be adjusted by selecting any one of a plurality of lower molds having cylindrical portions of different heights.

Table 4 shows the height and cavity height table of the condenser lens according to the size of the light emitting surface area for satisfying the target light distribution angle.

Target light distribution 20 30 40 50 60 70 80 90 Lens height 50% 50% 50% 10% 10% 8% 8% 6% Cavity height 45% 22.5% 13% 37% 29.5% 29% 26.2% 32.2% LES
14 Height 38.29 38.29 38.29 7.66 7.66 6.13 6.13 4.59 Cavity height 17.23 8.8 4.98 2.83 2.26 1.78 1.61 1.48 LES
11.2 Height 30.92 30.92 30.92 6.18 6.18 4.95 4.95 3.71 Cavity height 13.91 6.05 4.02 2.29 1.67 1.43 1.30 1.19

The surface of the cylindrical portion 16 and the outer surface of the injection space 14 may be releasably coated so as to easily demould be formed after the condenser lens 20 is manufactured.

In step S14, the liquid material, that is, the silicon and the curing agent are stirred using an agitator, and the stirred silicon is injected and dispensed in the dispensing space 14 of the mold 13 in a dispensing manner by the dispensing amount calculated in step S10.

The stirrer can agitate the silicone and the curing agent evenly using a centrifugal force in a vacuum state.

On the other hand, when the silicone is stirred with the curing agent, the viscosity gradually increases as the curing reaction starts from this point.

As described above, when the viscosity of silicon is increased, when discharging silicon using air having a constant pressure in the dispensing process, the discharge amount gradually decreases.

Accordingly, in step S16, silicon is dispensed onto the mold using a volume discharge system that discharges silicon at a predetermined volume by applying a screw instead of the air system.

In step S18, the liquid material injected into the mold 13 is heated and cured.

At this time, the time and temperature for heating and curing the liquid material may be changed depending on the raw material and amount of the liquid material.

For example, the curing process of the liquid material may be carried out for about 5 minutes by heating to a temperature of about 180 캜 when using a curing oven.

Alternatively, the curing process of the liquid material may be carried out at room temperature for about 24 hours.

According to the experimental results of the actual condenser lens, the curing process of the liquid material is preferably carried out at a temperature of about 80 캜 to about 180 캜 for about 70 minutes to about 5 minutes.

In such a curing step, curing may be performed in which a liquid material is reacted with sulfur, peroxides, metal oxides, radiation curing agents or the like to form bridge bonds between molecules.

The upper mold 17 and the lower mold 15 of the mold 13 are separated from each other at step S20 and the cured condensing lens 20 is demoulded.

Finally, the quality characteristic of the condensing lens 20 manufactured in the step S22 is inspected, and the defective product is removed according to the inspection result, and only the normal product is packaged.

Through the above-described process, the cavity can be formed at the center of the condensing lens, and the light emitted from the light source can be transmitted directly without passing through the condensing lens, thereby improving the condensing efficiency.

In particular, according to the present invention, the total reflection plane of the condensing lens is formed into a curved surface having a plurality of linear surfaces at different angles according to a design process, thereby totally reflecting the light emitted from the light source to the emission surface, Can be improved.

According to the present invention, the condensing lens of various light distribution angles can be manufactured by adjusting the height of the condensing lens by changing the injection amount of the liquid material supplied to one mold and adjusting the height of the cavity formed in the condensing lens.

In the present embodiment, a cavity is formed in a cylindrical shape in the condenser lens, but the present invention is not limited thereto.

For example, Fig. 17 is an illustration of an illumination condensing apparatus according to another embodiment of the present invention.

17, the cavity 21 is formed in a substantially cylindrical shape, and the upper surface of the cavity 21 is formed with a concave curved surface so as to improve the light condensing efficiency by adjusting the angle of refraction and reflection of light .

18 and 19 are exemplary views of a light condensing device for illumination according to another embodiment of the present invention, respectively.

The present invention can be modified so that a mounting block 40 is further formed so as to be mounted on an illuminating device (not shown) on the outer periphery of the upper end of the condenser lens 20, as shown in Fig.

The mounting block 40 is formed in a ring shape along the outer peripheral surface of the upper end of the condenser lens 20 and functions to be coupled to the tip of the illumination device.

19, the present invention can be modified to further include a fixing block 41 so as to be fixed to the illumination device together with the light source 11 at the lower part of the condenser lens 20. [

The fixing block 41 is formed in a ring shape corresponding to the lower shape of the condenser lens 20 so that the lower end of the condenser lens 20 is coupled, (42) may be formed.

The fixing block 41 may be fixed by fastening a fixing member such as a bolt to a mounting plate provided on a circuit board or an illumination device of the light source 11. [

On the other hand, the mounting block 40 and the fixing block 41 can be coupled to the condenser lens 20 by a heat fusion method or a bonding method.

According to the above-described process, the cavity is formed at the center of the condenser lens to transmit the light emitted from the light source directly without passing through the condenser lens to improve the condensing efficiency, and the liquid material By changing the height of the condensing lens by adjusting the injection amount, it is possible to manufacture condensing lenses of various light distribution angles.

According to the present invention, the total reflection surface of the condensing lens is formed into a curved surface having a plurality of linear surfaces at different angles according to a design process, and the height of the cavity is adjusted so that light emitted from the light source is totally reflected on the emission surface, Efficiency and efficiency of the lighting device can be improved.

Although the invention made by the present inventors has been described concretely with reference to the above embodiments, the present invention is not limited to the above embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

According to the present invention, a cavity is formed in a central portion of a condenser lens to directly transmit light irradiated from a light source without passing through a condenser lens to improve condensing efficiency, change the injection amount of the liquid material supplied to one mold, To a technique of manufacturing a condensing lens of various light distribution angles.

10: condensing device for illumination
11: Light source 12: Light emitting surface area
13: mold 14: injection space
15: lower mold 16: cylindrical part
17: upper mold 20: condensing lens
21: cavity 22: incident surface
23: total reflection surface 24: exit surface
40: mounting block 41: fixed block
42: Insertion space

Claims (10)

A light concentrating apparatus for illumination that locally illuminates distant light by condensing light emitted from a light source,
And a condensing lens which is formed in a conical cylindrical shape whose upper and lower surfaces are respectively circular and smaller in diameter toward the lower portion,
Wherein a center portion of the condenser lens is provided with a cavity through which a part of the light emitted from the light source is transmitted and an incident surface through which light emitted from the light source is incident is formed on an outer circumferential surface,
Wherein the cavity is formed to have a diameter corresponding to the size of the light emitting surface of the light source and the outermost dimension of the dam, and directly transmit a part of the light irradiated from the light source,
Wherein the total reflection surface formed on the side surface of the condenser lens is formed in a shape of a rotating body having a plurality of straight lines at different angles, and the light refracted at the incidence surface is irradiated to the upper surface of the condenser lens The light is totally reflected so as to exit parallel to the optical axis through the exit surface,
Wherein each linear surface of the total reflection surface is formed to have an angle larger than a critical angle corresponding to an angle of a light beam emitted from the light source and a refractive index of air and a liquid material so that light reaching the incident surface is totally reflected Progress,
The angle between the bottom of the focusing lens and the bottom of the focusing lens increases,
The height of the condensing lens is adjusted based on an injection amount of the liquid material injected into the injection space formed in one mold,
Wherein the injection amount of the liquid material is changed according to a light distribution angle of the condensing lens to be implemented. delete The method according to claim 1,
Wherein the cavity is changed in height according to a light distribution angle of the condensing lens to be implemented so as to prevent light reflected by the incident surface and directly emitted through the emission surface from being reflected by the emission surface. The method of claim 3,
Wherein the light distribution angle of the condensing lens increases as the height of the condensing lens decreases,
And the efficiency of the converging lens rises as the height of the cavity decreases. delete A method of manufacturing an illumination light concentrating apparatus for locally illuminating distant light by condensing light emitted from a light source,
(a) calculating a height of the condensing lens based on a light distribution angle of the condensing lens to be manufactured, calculating a height of the condensing lens based on the calculated height of the condensing lens, Calculating an injection amount,
(b) injecting the liquid material into the injection space of the mold by the injection amount calculated in the step (a); and
(c) heating and curing the liquid material injected into the mold and releasing the cured condensing lens from the mold,
Wherein a center portion of the condenser lens is provided with a cavity through which a part of the light emitted from the light source is transmitted and an incident surface through which light emitted from the light source is incident is formed on an outer circumferential surface,
Wherein the cavity is formed to have a diameter corresponding to the size of the light emitting surface of the light source and the outermost dimension of the dam, and directly transmit a part of the light irradiated from the light source,
Wherein the light collecting lens has a plurality of linear surfaces at different angles so as to totally reflect light emitted from the light source and refracted first in the incident surface through an exit surface formed on the upper surface of the collecting lens in parallel with the optical axis A total reflection surface is formed in the shape of the rotating body,
Wherein each linear surface of the total reflection surface is formed to have an angle larger than a critical angle corresponding to an angle of light emitted from the light source and a refractive index of air and the liquid material so that light reaching the incident surface is totally reflected , ≪ / RTI >
The angle between the bottom of the focusing lens and the bottom of the focusing lens increases,
The outer peripheral surface of the injection space is formed in a shape corresponding to the total reflection surface,
Wherein the liquid material is injected into the injection space of the mold by a dispensing method using a volume ejection system for ejecting a predetermined volume using a screw in the step (b). The method according to claim 6,
A cylindrical portion corresponding to the shape of the cavity is formed in the injection space of the mold,
Wherein the height of the cylindrical portion is changed according to a height of the calculated cavity. delete delete delete

Images