JP2006196931A - Lens integrated light emitting element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a condenser lens enabling to achieve a strictly controlled light distribution characteristics by efficiently emitting light produced from a light source in a predetermined direction. <P>SOLUTION: A condenser lens 120 made of an acrylic material includes an entrance plane 122 for introducing light emitted from a light emitting element 113, and an exit plane 121 for emitting light having a flat light intensity by deflecting light entered from the entrance plane 122 such that vertical outgoing direction is controlled to be within a predetermined range of angle, and horizontal outgoing direction is not controlled. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a condensing lens, a lens-integrated light emitting element, and a lighting device, and more particularly, to a lens suitable for use in an aircraft obstacle light, a signal light, and the like.

Aviation obstruction lights for indicating the position and height of high-rise buildings with respect to aircraft and the like have been used conventionally. Currently, air traffic lights that are used are mainly light bulb type lamps that control light distribution using large lenses. Aviation obstruction lights are usually installed in places that are difficult for people to approach, such as the rooftops of high-rise buildings, and it has been desired to reduce the frequency of maintenance such as bulb replacement.

On the other hand, in recent years, LEDs (light-emitting diodes) have rapidly increased in brightness, and a large amount of power LED
Is being commercialized. Since an LED generally has a longer life than a light bulb, it has been expected to have a great merit, for example, a maintenance interval can be increased by five times.

However, when the light source is switched from the light bulb to the LED, the design and configuration of the aviation obstacle light must be changed significantly. In other words, in contrast to a light bulb type in which a large light distribution lens is arranged around one or two light bulbs, it is possible to generate an equivalent amount of light unless a much larger number of LEDs (nearly 1000) are integrated. difficult.

For this reason, the distribution area of the light emitting points in the lamp body must be much larger than that of the light bulb. Therefore, it is impossible to control the light distribution with a single large lens.
Since it is necessary to control the light distribution by attaching a small light distribution lens for each ED, it can be said that the light distribution control as a whole becomes difficult.

Conventionally, in aviation obstruction lights for applications where only a lower light intensity is required, many small LEDs with a bullet-type lens are integrated to achieve a certain light intensity. As this type of aviation obstacle light, for example, a configuration as disclosed in Utility Model Registration No. 2553515 or Japanese Patent Laid-Open No. 09-069304 is known.

FIG. 20 is a side view of the aviation obstacle light 10 using such an LED with a part cut away.
The aviation obstacle light 10 includes a base 11 and a light emitting unit 12 supported by the base 11.
The light emitting unit 12 includes a cone-shaped support unit 13 that supports an LED 15 with a bullet-type lens, which will be described later, and a cover 14 that covers the support unit 13. On the outer periphery of the support portion 13, about 1000 LED 15 with bullet-type lenses are densely arranged.

Each LED 15 with a bullet-type lens is configured as shown in FIG. 21, for example, and includes a bullet-type lens 15a and a light emitting element 15b accommodated therein. These single LED 15 with a bullet-type lens have an axisymmetric shape, and emit light in a conical range of about 30 ° around the axial direction. By arranging these closely around the support portion 13, a light distribution that concentrates in a range of about 30 ° centering on the horizontal direction or slightly above the horizontal has been realized.
Utility Model Registration No. 2553515 JP 09-069304 A

The above-mentioned aviation obstacle light has the following problems. In other words, in aviation obstacle lights for higher-luminance applications, high luminosity is required in a given direction, and consideration is given to avoiding environmental pollution due to leakage of high-luminance light in other directions. Is required.

The luminous intensity distribution light distribution characteristic of the aviation obstacle light is defined, for example, by the Aviation Obstruction Light Specification No. 243 Rev. 6 issued by the Ministry of Land, Infrastructure, Transport and Tourism, Aviation Bureau Control and Safety Department, Safety Planning Section, Navigation Visual Assistance Business Office. This rule is quite technically strict in accordance with recent movements to protect the living environment.
In particular, as shown in FIG. 22, when the vertical angle is between -1 ° and 0 °, the upper and lower limits of luminous intensity are very narrow and rise rapidly.

For this reason, the conventional LED 15 with a bullet-type lens having a light distribution spread of 30 ° cannot be used. In addition, there is a problem that it is difficult to set the light utilization efficiency higher than a certain degree in order to realize a steep change in luminous intensity required at a distance.

Accordingly, the present invention provides a condensing lens, a lens-integrated light emitting element, and a lighting device that can realize light distribution characteristics that are strictly regulated by efficiently emitting light generated from a light source in a predetermined direction. It is intended to provide.

In order to solve the above problems and achieve the object, a lens-integrated light emitting device according to the present invention includes a light emitting portion and a transparent member in a used wavelength range, and condenses light emitted from the light emitting portion. A condensing lens, an incident surface for introducing light emitted from the light emitting unit,
The incident light is deflected from the incident surface, the emission direction is regulated within a predetermined angular range at least in the predetermined direction, and light having a flat luminous intensity distribution is emitted, and the outer periphery of the cut surface parallel to the predetermined direction is emitted. At least a part of which is formed in the shape of a part of an ellipse, and the light emitting part has an end located on the major axis of the ellipse.

According to the present invention, light generated by a light source is effectively guided in a predetermined direction, and highly efficient light distribution is possible with a simple configuration.

FIG. 1 is a perspective view showing a lens-integrated light emitting device 100 according to the first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view showing the lens-integrated light emitting device 100. Lens-integrated light emitting device 100
Are affixed to the outer wall surface of a cylindrical light-emitting element holder as shown in FIGS. 15 and 16, which will be described later, and used as an aviation obstacle light or the like disposed on a high-rise building rooftop or the like. When used as an aviation obstruction light, it emits light in all directions in the vicinity of the horizontal direction, but emits light only in the necessary direction so that light is hardly emitted obliquely downward or obliquely upward, etc. The property of not emitting light in an unnecessary direction is required. The predetermined plane is a plane including the vertical direction (Z axis) and the optical axis direction (X axis).

The lens-integrated light emitting device 100 includes a light emitting device 110 and a condensing lens 120 attached to the light emitting device 110.

The light emitting device 110 includes an element base 111 and a recess 11 provided in the element base 111.
2 and a micro light-emitting portion 113 such as an LED chip provided on the bottom surface of the recess 112. The concave portion 112 is filled with a transparent substance 114 such as a silicon resin to protect the minute light emitting portion 113. The transparent material 114 is preferably made of the same material as that of the condensing lens 120 or a material having a refractive index that is the same as or substantially the same as the refractive index of the material of the condensing lens 120.

The condensing lens 120 is a columnar lens and has an exit surface (ellipsoidal column surface) 121 and an entrance surface 122. The cross-sectional shape of the emission surface 121 is a combination of a half of an ellipse Q and a rectangle in which the minute light emitting portion 113 is positioned near the focal point Qf. As a material of the condensing lens 120, for example, a highly light-transmitting resin such as acrylic or polycarbonate, or a light-transmitting optical glass is preferable.

A specific shape of the ellipse Q will be described with reference to FIG. The long half length of the ellipse Q is L,
When the refractive index of the lens material is n, the distance f between the center point Qc of the ellipse Q and the focal point Qf is
f = L / n (1)
It can be expressed as. When a point light source is placed at the focal point Qf of the ellipse Q, the emission surface 121
The light ray K emitted from the light becomes parallel to the long axis of the ellipse Q. Accordingly, by arranging the minute light emitting portion 113 near the focal point Qf, the effect of deflecting the angle formed by the propagation direction of the light beam K and the major axis within a minute angle for most of the light rays K emitted from the emission surface 121. Is obtained.

Further, the same or similar effect as described above can be obtained even on a cross section other than that shown in FIG. Therefore, the minute light emitting part 11
A flat luminous intensity distribution can be obtained by the light emitting device 110 including 3 and the condenser lens 120.

As described above, according to the lens-integrated light emitting device 100 according to the first embodiment of the present invention, the light generated from the light source is efficiently emitted in the horizontal direction, and almost no light is emitted in the other directions. It is possible to realize a strictly regulated light distribution characteristic without emitting light.

FIG. 3 is a longitudinal sectional view showing a lens-integrated light emitting device 100A according to a first modification of the lens-integrated light emitting device according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

The condensing lens 120 of the lens-integrated light emitting element 100A is formed so that the relative size of the ellipse Q ′ with respect to the minute light emitting portion 113 is smaller than that of the lens-integrated light emitting element 100 described above. The width of the flat luminous intensity distribution at a distance is an ellipse Q with respect to the size of the minute light emitting portion 113.
In the case of the first modified example, the width of the luminous intensity distribution becomes wider.

FIG. 4 is a longitudinal sectional view showing a lens-integrated light emitting device 100B according to a second modification of the lens-integrated light emitting device according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

The condensing lens 120 of the lens-integrated light emitting element 100B is formed to have a larger relative size of the ellipse Q ″ with respect to the minute light-emitting portion 113 than the lens-integrated light emitting element 100 described above. The width of the distribution is elliptical Q with respect to the size of the minute light emitting portion 113.
In the case of the second modification, the width of the luminous intensity distribution becomes narrow.

As shown in the lens-integrated light emitting devices 100A and 100B, by changing only the size without changing the shape (eccentricity) of the ellipse Q, the magnitude of the spread of the luminous intensity distribution can be freely set to a desired angle. It becomes possible to control.

FIG. 5 is a longitudinal sectional view showing a lens-integrated light emitting element 100C according to a third modification of the lens-integrated light emitting element according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

The lens-integrated light emitting element 100 </ b> C has an end 113 a of the minute light emitting unit 113 on the long axis of the ellipse Q.
The emission surface 121 is arranged so that is positioned. When arranged in this way, the effect that the luminous intensity distribution changes very steeply above and below the major axis direction of the ellipse Q is also obtained, and the horizontal direction (major axis direction) is obtained.
It is possible to emit intense light slightly above the horizontal direction while emitting little light below.

FIG. 6 is a longitudinal sectional view showing a lens-integrated light emitting element 100D according to a fourth modification of the lens-integrated light emitting element according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

In the lens-integrated light emitting element 100D, the ellipse Q is inclined with respect to the normal direction of the light emitting device 110, and the emission surface 121 is arranged so that the end of the minute light emitting unit 113 is positioned on the long axis of the ellipse Q. ing. As a result, it is possible to realize a steep luminous intensity distribution that emits little light below the desired elevation direction but emits intense light slightly above the horizontal direction.

FIG. 7 is a longitudinal sectional view showing a lens-integrated light emitting element 100E according to a fifth modification of the lens-integrated light emitting element according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

In the lens-integrated light emitting element 100 </ b> E, two light emitting devices 110 are attached to one condenser lens 120. Note that the number of light emitting devices 110 is not limited to two, and a plurality of light emitting devices 110 may be attached. Similar effects can be obtained in this modification.

FIG. 8 is a longitudinal sectional view showing a lens-integrated light emitting element 100F according to a sixth modification of the lens-integrated light emitting element according to the first embodiment. 1 and 2 described above in FIG.
The same functional parts are denoted by the same reference numerals, and detailed description thereof is omitted.

In the lens-integrated light emitting element 100F, the condensing lens 120 is continuously provided in a ring shape, and a large number of light emitting devices 110 are mounted inside the ring.

In such a configuration, the condenser lens 1 is used for each light emitting device 110.
Reference numeral 20 can be regarded as an elliptical columnar lens similar to the lens-integrated light emitting device 100 shown in FIG. In this way, when a signal lamp or the like is manufactured by combining a plurality of lens-integrated light emitting elements, it is possible to reduce the number of manufacturing processes or increase the degree of integration of LED elements.

In addition, a flat luminous intensity distribution having a desired direction and a desired width can be obtained by appropriately combining the lens-integrated light emitting elements 100 and 100A to 100F described above.

FIG. 9 is a side view of the lens-integrated light emitting device 200 according to the second embodiment of the present invention viewed from the Y-axis direction, and FIG. 10 is a plan view viewed from the z-axis direction. As shown in FIGS. 9 and 10, the origin Σ of the coordinate system is taken on the light emitting surface of the light emitting diode chip 212, and the light emitting diode chip 21.
The X axis is taken in the direction perpendicular to the light emitting surface 2 and the Y axis and the Z axis are taken in parallel directions. X axis, Y axis,
The Z axes are in a relationship orthogonal to each other. With the application to the aviation obstacle light in mind, it can be said that the Z axis is the vertical direction, the X axis is the optical axis direction, and the XY plane is the horizontal plane.

The lens-integrated light emitting device 200 is affixed to the outer wall surface of a cylindrical light emitting device holder as shown in FIG. 15 and FIG. Is. The lens-integrated light emitting element 200 is also required to have the same performance as the lens-integrated light emitting element 100 described above.

The lens-integrated light emitting element 200 includes a light emitting device 210 and a condensing lens 220 made of an acrylic material having a refractive index of 1.49 attached to the light emitting device 210. The light emitting device 210 includes a square tray portion 211 having a side of 6.8 mm, and the tray portion 211.
And a light emitting diode chip 212 having a small square shape with one side of 550 μm.

The condensing lens 220 is a part of a rotationally symmetric surface with respect to the Z axis, and the cross-sectional shape in the XZ plane is a part of an ellipse T as shown in FIG. This ellipse T in the X-Z plane has one first focal point T on the origin located on the light emitting surface of the light emitting diode chip 212.
It has f1, and the other second focal point Tf2 is located substantially in the X-axis direction. The first focus Tf of this ellipse
The distance δ between 1 and the second focal point Tf2 is equal to a value obtained by dividing the entire major axis of the ellipse T by the refractive index 1.49 of the condenser lens 220. The condensing lens 220 has a surface that is generated by rotating the ellipse T in the XZ plane as described here with the z axis as the rotation axis 230. However, the part of x <0 and other unnecessary parts are removed.

The light beam K emitted from the light emitting diode chip 212 travels through the acrylic medium, undergoes a refracting action on the exit surface of the condenser lens 220, and exits outside the lens.

Next, the function of the lens-integrated light emitting element 200 will be described. The light ray K is diverged only in the horizontal direction by the light emitting diode chip 212 and the condenser lens 220 described above.

In the xz plane shown in FIG. 9, when the second focal point Tf2 is on the x-axis, the first focal point Tf
The light beam K emitted 1 becomes a light beam K parallel to the x-axis by the refraction action of the condenser lens 220. That is, when the focal length of the ellipse is a value obtained by dividing the major axis half length by the refractive index n of the lens medium,
The ellipse equation is

It is expressed. At this time, from the first focus Tf1 (x = 0, z = 0), an arbitrary point (x
, Z) to be a distance √ (x ² + z ² )

It can be seen that it is. The optical path length multiplied by n is na− (a / n) + x. This refraction point (
x, z) to the plane x = a + (a / n) parallel to the x-axis, a + (a / n) −
When x is added, the surface of x = a + (a / n) does not depend on the position (x, z) of the refraction point, and becomes an equiphase surface of the optical path length na + a. That is, it can be seen that the light beam K emitted from the first focal point Tf1 is refracted by the elliptical condenser lens 220 and then becomes parallel light parallel to the x-axis.

The above is true in a cross section by an arbitrary plane passing through the z-axis. Therefore, the light ray K can be concentrated in the vicinity of the horizontal direction in all directions where the lens surface exists.

The present invention is not limited to the lens-integrated light emitting device 200 according to the second embodiment. For example, in the lens-integrated light emitting device 200, the elliptical second focal point Tf2 in the XY plane is placed on the X axis, but may be placed above or below the X axis.

For example, as shown in FIG. 11, when the second focal point Tf2 is placed 5 ° above the x axis,
The direction of the outgoing light beam K is directed 5 ° above the horizontal direction. In this way, by adjusting the position of the second focal point Tf2, it is possible to easily adjust how many times the light is emitted upward or downward from the horizontal direction.

Further, in the lens-integrated light emitting device 200, it has been described that the rotating shaft is installed vertically upward with the aviation obstacle light in mind, but the present invention relates to a component called a lens integrated light-emitting device, The installation direction may be any direction and need not be fixed.

Further, the first focal point Tf1 of the ellipse T may be located at the center of the light emitting diode chip 212, at the end, or at any location. Light emitting diode chip 2
When the first focal point Tf1 is located near the center of 12, the distribution of the emitted light is a stable distribution that is substantially symmetrical up and down. Further, when the elliptical first focus Tf1 is located at the end of the light emitting diode chip 212, the distribution of the emitted light suddenly increases or decreases with the emission direction set by the second focus Tf2 as a boundary, A sharp cut-off angle can be realized.

Also, as shown in FIG. 12, when the light-emitting diode chip 212 is placed at a position deviated from the elliptical first focal point Tf1, the second focal point Tf2 is moved from the X-axis even when the second focal point Tf2 is on the X-axis. As in the case of being placed above or below, it is possible to easily adjust how many times the outgoing light is directed downward or upward from the horizontal direction. In this case, compared with the case where the end of the light emitting diode chip 212 is positioned on the first focal point Tf1 of the ellipse and the second focal point of the ellipse is located above or below the X axis, the distribution of the emitted light is abrupt. No increase or decrease is seen or mitigated.

FIG. 13 is a diagram showing a lens-integrated light emitting element 200A according to a modification of the lens integrated light-emitting element 200 according to the second embodiment, FIG. 12 (a) is a front view, and FIG. 12 (b) is a plan view. Figure, (
c) is a side view. 13 and 14, the same functional parts as those in FIGS. 9 and 10 described above are denoted by the same reference numerals, and detailed description thereof is omitted.

The condensing lens 220 in this modification is formed by rotating a plane combining an ellipse and a rectangle 180 degrees around the symmetry axis M. In the figure, 221 indicates a flat surface, and 222 indicates a deleted portion. Also in this modification, the same effect as the above-described lens-integrated light emitting element 200 can be obtained.

FIG. 15 and FIG. 16A are schematic views showing the configuration of a lens-integrated light emitting device 300 according to the third embodiment of the present invention. The lens-integrated light emitting element 300 includes a light emitting element 310 such as an LED serving as a light source, and a condenser lens 320 to which the light emitting element 310 is attached.

The condensing lens 320 is provided with a concave light source mounting position 321 having an appropriate depth so as to ensure the mounting position accuracy. The light emitting element 310 is attached to the light source mounting position 321 with an adhesive or the like. A lens-integrated light emitting device 300 as an assembly component is configured. In order to reduce the cost during mass production, for example, when the condenser lens 320 is formed of resin, the light emitting element 310 is previously placed at a predetermined position of the lens mold, and when the condenser lens 320 is formed, resin and It is also possible to configure so as to be integrated. As described above, whether the condenser lens 320 is manufactured as a single unit and integrated later or manufactured as an integrated element from the beginning can be selected depending on the manufacturing quantity and other conditions.

When the light emitting element 310 emits light, light is taken into the condensing lens 320 through the contact surface between the condensing lens 320 and the light emitting element 310 at the light source mounting position 321, propagates through the lens, and then condenses the lens 320. Light is emitted to the outside of the lens through the exit surface 322 of the lens.

FIG. 15 shows a representative light beam J that indicates the propagation of light inside the lens, and a light beam E that is deflected by the exit surface 322 of the condensing lens and that propagates far away outside the lens. Further, angles ψ _x , ψ _y , θ _x , and θ _y for representing the propagation directions of these rays J and E are illustrated.

The emission surface 322 has a specific shape that realizes a predetermined flat light intensity distribution in the distance.
Next, an example of a method for determining such a specific shape will be shown. In order to show a specific example, an example of a specific shape is shown, but the present invention is not limited to the shape shown in this embodiment.

First, the exit surface 322 is a free-form surface, and the back surface and side surface of the condenser lens 300 are planes orthogonal to each other as shown in the figure. The contact surface of the light emitting element 310 is installed near the center of the back surface. As shown in FIG. 15, within the contact surface of the light emitting element 310, the horizontal direction is the X axis and the vertical direction is Y.
The Z axis is taken in a direction perpendicular to both axes and corresponding to the front surface of the light emitting element 310. The specification of the luminous intensity at a distance is such that it is uniform as much as possible without depending on the azimuth angle in the horizontal direction, and has a steep peak with respect to the elevation angle in the vertical direction. To make it easier to evaluate such characteristics, we will describe the direction of the light beam in terms of azimuth and elevation.

Specifically, as shown in FIG. 15, the direction of the light beam J emitted from the light emitting element 310 and incident on the output surface 322 is (ψ _x , ψ _y ), and the light beam is refracted and output from the output surface 322. The direction of E is represented by (θ _x , θ _y ).

A target value in the propagation direction of the refracted outgoing light K is set for several sample light rays J emitted from the central point of the light emitting element 310. However, individually setting target values for the light rays J of a large number of samples is complicated as a design procedure, and it is difficult to proceed with design improvement and the like with good prospects. Therefore, the target direction is automatically set using mapping.

The luminous intensity distribution from the light emitting element 310 is defined as I _S (ψ _x , ψ _y ). Also, _let the target light intensity distribution be I _F (θ _x , θ _y ). First, a region I in the (ψ _x , ψ _y ) space: −w _xS
<Ψ _x <w _xS , -w _yS <ψ _y <w _yS is considered, and the propagation direction (θ _x , θ _y ) after emission is made to correspond to the direction (ψ _x , ψ _y ) in the region I. Define the mapping as follows:

As the first step of mapping, intermediate parameters f _rx and f _ry are defined. This f
The values of _rx and f _ry are obtained from the value of (ψ _x , ψ _y ) and the light intensity distribution IS (ψ _x , ψ _y ) of the light source,

It shall be defined in Here, cos _{ψ y} , dψ _x , and dψ _y correspond to minute solid angle elements.

As a second step of mapping, corresponding θ _x and θy are determined according to the intermediate parameters f _rx and f _ry . First, when ψ _x = const, the corresponding (θ _x , θ
_y ), where h is a constant,
θ _x = f (θ _y , η) (6)
It is assumed that the relationship is given by a certain function f. However, as ψx increases, the corresponding value of h also increases. Without loss of generality, when ψ _x = 0, h = 0, ψ _x = w _xS
In this case, it is assumed that h = 1. First, for the value of the intermediary parameter _frx ,

To obtain h. Furthermore, using the obtained h,

To obtain θ _y . Further, θ _x is also determined using Equation (6).

The function f is not limited to a specific function form as long as the above properties are satisfied. In this example, a simple and easy-to-use function form is adopted.
f (θ _y , η) = ηw _xs (9)
It was. Depending on the characteristics of the designed one, it may be better to use a function that depends on θ _y , so a more complicated function form may be used as necessary.

The function I _S (ψ _x , ψ _y ) may be set to 1 for simplicity, but if it is assumed to be a minute perfect diffuse light source,
I _S (ψ _x , ψ _y ) = cosψ _x cosψ _y (10) may be proportional to the cosine of the angle from the normal direction.

Function _{I F (θ x, θ y} ) about, although convergence of the not set close to physically realizable form optimization calculation is expected to be poor, this time simply represent flat shape Like

A uniform light intensity function is assumed as follows.

If the width of the luminous intensity distribution is determined by the size of the light source, it is necessary to set the target so that it is as narrow as possible. However, if the size of the light source is sufficiently smaller than the lens and the width of the luminous intensity distribution is determined by light distribution control Needs to adjust the function I _F (θ _x , θ _y ).

An appropriate number of sample rays J are set within the range of the region I in which the mapping is defined. However, after several trials, the region where the emission angle from the light emitting element 310 is large around the region has a large incident angle on the emission surface 322, and the convergence of the optimization calculation is deteriorated. Therefore, the sample light beam J was set in a region having a small emission angle. In particular,

The light ray J of the sample was set from this range.

The exit surface 322 is called a free-form surface, but is mathematically a curved surface described by a finite number of surface parameters. If a sufficient degree of freedom is given using an appropriate function form, it is considered that a function close to the performance of a free-form surface can be realized. The curved surface is given in the form of z = g (x, y). The function g can reduce the calculation load by making the function value and the partial differential coefficient based on x, y easy to calculate. The polynomials of x, y, etc. are preferable from this point of view, but the higher-order terms increase rapidly around the periphery, so they are somewhat difficult to handle and tend to have poor convergence. Therefore, the following function form was adopted this time.

Here, p _s1 is the lens center thickness, and g (x, y) is a function that becomes 0 at the origin. In other words, an offset was added to the cosine function so that the value at the origin is 0 although it is based on a trigonometric function. Except for this point, the format is defined by the Fourier series in the region of the period (p _x , p _y ). In addition, in order to make it a positive and negative symmetrical shape about the x direction, the component which becomes antisymmetric about x was abbreviate | omitted.

  It was confirmed that the curved surface converged under the following conditions.

Lens center thickness: p _s1 = 35 (mm)
Lens refractive index: n = 1.49
Function parameter: p _S = 40.0 (mm)
Function parameter: p _y = 40.0 (mm)
Area I horizontal width: w _xS = 29.0 (degrees)
Area I vertical width: w _yS = 29.0 (degrees)
Target horizontal angle: w _x = 24.0 (degrees)
Target upper elevation angle: w _xU = 0.8 (degrees)
Target lower elevation angle: w _xL = 0.2 (degrees)
In this way, when it is possible to theoretically determine the exit surface shape having predetermined characteristics, it is not necessary to determine the surface shape by the optimization calculation as shown in the above example. However, the case where such a determination can be made is relatively limited. The method of determining the surface shape by the optimization calculation as described above is as follows.
Although it does not necessarily exactly match the desired characteristics, it achieves characteristics that are as close to the desired characteristics as possible within the range of degrees of freedom, and can flexibly handle many applications, and is sufficient in many cases. This is a practical method that can realize characteristics with high accuracy. In any case, the design method may be selected in view of the application, required accuracy, and other conditions, and the specific method for determining the curved surface is not limited.

In the above description, the case where the light emitting element 310 that is a light source is in direct contact with the condenser lens 320 has been described in detail, but the same applies to a configuration in which the light emitting element 310 is installed at a predetermined position outside the condenser lens 320. Can be designed.

FIG. 16B shows a lens-integrated light emitting element 3 according to a modification of the lens-integrated light emitting element 300.
It is a figure which shows 00A. The lens-integrated light emitting element 300 </ b> A includes a light emitting unit 330 and a condenser lens 340 to which the light emitting unit 330 is attached. The light emitting unit 330 includes a light source holder 331 and a light emitting element 332 supported by the light source holder 331. The condensing lens 340 includes an incident surface 341 having a convex shape toward the light emitting element 332 and an exit surface 342 having the same shape as the exit surface 322 of the collective lens 320 described above. Since the incident surface 341 has a convex shape toward the light emitting element 332, the lens power can be increased, but the degree to which the surrounding light suffers loss due to reflection often increases.

Conversely, a concave shape toward the light emitting element 332 may be used. The light emitting element 332 needs to be held at a predetermined position outside the condenser lens 340. The means for this is not particularly limited, and the light emitting element 332 and the condenser lens 340 may be installed in the apparatus as separate and independent components. Therefore, in the example of FIG. 16B, the light source can be installed at a predetermined position via the light source holder 331.

(Fourth embodiment)
FIG. 17 is a cross-sectional view showing a lighting device 400 according to the fourth embodiment of the present invention, and FIG. 18 is a side view showing the lighting device 400 with a part cut away. As a specific application of such a lighting device 400, there is an aviation obstacle light arranged on a high-rise building rooftop or the like.

The lighting device 400 includes a pedestal 401, a light emitting element holder 402 that holds a plurality of lens-integrated light emitting elements 404, which will be described later, a cover 403 that covers the light emitting element holder 402, and a lens integrated light emitting element that is attached to the light emitting element holder 402. An element 404 is provided.

The pedestal 401 has a disk shape or a conical shape. In the embodiment shown in FIG. 17, a space portion 401a capable of storing a circuit board, a wiring cord, and the like is provided therein. Note that in the case of a configuration in which a circuit board, a wiring cord, and the like are housed in the light emitting element holder 402, it is not necessary to provide the space 401a. Further, as a material of the pedestal, a lens-integrated light emitting element 404 is used.
In order to function as a radiator that radiates heat generated from the light and conducted from the light emitting element holder 402, it is preferable to use a material having thermal conductivity.

The light emitting element holder 402 is installed on the pedestal 401 and has a cylindrical shape. The light emitting element holder 402 can accommodate a driving circuit board, a wiring cord, and the like of the lens integrated light emitting element 404. The shape is not necessarily limited to a cylindrical shape as shown in FIG. 17, and may be a polygonal shape such as a hexagonal shape or an octagonal shape or a cylindrical shape having an elliptical cross section. Further, as the material of the light emitting element holder 402, it is preferable to use a thermally conductive material in order to function as a radiator that dissipates heat generated from the lens-integrated light emitting element 404.

The cover 403 is composed of a cap part and a cylindrical part on the dome, and the whole is constituted by a transparent member such as glass or plastic. The cover 403 protects the upper part of the lens-integrated light emitting element 404, the light emitting element holder 402, and the base 401.

The lens-integrated light emitting element 404 is a combination of the condensing lens and the light emitting element described in the first to third embodiments described above. The lens-integrated light emitting element 404 includes:
A plurality of light emitting element holders 402 are arranged on the side surface, and are arranged in parallel at a predetermined interval in the circumferential direction.

For each of the lens-integrated light emitting elements 404, the vertical angle direction is narrow and a flat luminous intensity distribution having a spread in the horizontal direction is obtained. By arranging the lens integrated light-emitting elements in the circumferential direction, the vertical angle direction is A light intensity distribution that is narrow and uniform in all horizontal directions can be obtained. Further, the vertical arrangement of the lens-integrated light emitting elements 404 is arranged in series in the vertical direction in the embodiment shown in FIGS. 17 and 18.

If the lighting device 400 configured as described above is used, a light intensity distribution that is narrow in the vertical direction and uniform in all horizontal directions can be obtained. For example, an aviation obstacle light is installed on the roof of a high-rise building and is used to notify an aircraft of the presence of an obstacle, and it is not necessary to emit a lot of light downward or upward. Therefore, it is effective to construct a high-efficiency aviation obstacle light that emits light only in a necessary direction without emitting light in an unnecessary direction by the lighting device 400 of the present invention.

FIG. 19 is a side view showing a lighting device 400A according to a modification of the lighting device 400 with a part cut away. 19, the same functional parts as those in FIGS. 17 and 18 are denoted by the same reference numerals, and detailed description thereof is omitted.

The arrangement direction of the lighting device 400A in series is not limited to the vertical direction, but may be arranged in an oblique direction inclined from the vertical direction as shown in FIG. In this modification, the lighting device 400 described above is used.
The same effect as above can be obtained, and the horizontal uniformity of the luminous intensity distribution can be improved.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

1 is a perspective view showing a lens-integrated light emitting element according to a first embodiment of the present invention. The longitudinal cross-sectional view which shows the lens integrated light emitting element. The longitudinal cross-sectional view which shows the 1st modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the 2nd modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the 3rd modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the 4th modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the 5th modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the 6th modification of the light emitting element integrated with the lens. The longitudinal cross-sectional view which shows the lens integrated light emitting element which concerns on the 2nd Embodiment of this invention. The cross-sectional view which shows the lens integrated light emitting element. The longitudinal cross-sectional view which shows the lens integrated light emitting element. The longitudinal cross-sectional view which shows the modification of the lens integrated light emitting element. The perspective view which shows the modification of the light emitting element integrated with the lens. It is a figure which shows the modification, Comprising: (a) is a front view, (b) is a top view, (c) is a side view. The perspective view which shows the lens integrated light emitting element which concerns on the 3rd Embodiment of this invention. (A) is a longitudinal cross-sectional view showing the lens-integrated light emitting element, and (b) is a longitudinal cross-sectional view showing a modification of the lens-integrated light emitting element. The cross-sectional view which shows the lighting apparatus which concerns on the 4th Embodiment of this invention. The side view which shows the lighting apparatus partially cut away. The side view which shows a modification of the lighting device partially cut away. The side view which cuts and shows the conventional lighting apparatus partially. The side view which shows the light emitting element attached to the lighting apparatus. The figure which shows an example of the light intensity distribution light distribution characteristic of an aviation obstacle light.

Explanation of symbols

100, 100A to 100F, 200, 200A, 300 ... Lens-integrated light emitting element 110, 210, 310, 330 ... Light emitting device 120, 220, 320, 340 ... Condensing lens 400, 400A ... Lighting device

Claims (3)

A light emitting unit;
Consists of a transparent member in the operating wavelength range, and having a condenser lens that condenses the light emitted from the light emitting unit,
The condensing lens has an incident surface for introducing light emitted from the light emitting portion, and deflects light incident from the incident surface so that the emission direction is restricted within a predetermined angular range at least in a predetermined direction. Emitting light having a luminous intensity distribution, and having an emission surface in which at least a part of the outer periphery of the cut surface parallel to the predetermined direction is formed in the shape of a part of an ellipse,
The light emitting part has an end located on the major axis of the ellipse. The lens-integrated light-emitting element according to claim 1, wherein the ellipse is arranged to be inclined with respect to a normal direction of the light-emitting portion. 2. The lens according to claim 1, wherein the first focal point of the ellipse is located at the end portion, and the second focal point of the ellipse is disposed apart from the normal line of the light emitting unit. Body light emitting device.

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