JP5370661B2 - Gas station canopy lights - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a canopy light of a gasoline station, capable of lighting a lower part of a canopy and its ambience brightly enough without bringing about nuisances caused by light to neighboring residents or the like, and facilitating maintenance works with a simple configuration. <P>SOLUTION: The canopy light 70 of the gasoline station is constituted, in order to prevent the light of the canopy light 70 from leaking to outside of the site, by designing so that a directional angle &Theta; of the canopy light 70 is equal to an angle (or smaller than or qual to the angle) calculated by a formula &theta;=arctanä(H-h)/L}, wherein L is the shortest horizontal distance between the canopy light arranged on a lower surface of a canopy 54 of the gasoline station and a fire prevention wall 60 arranged in an outer periphery of the site, H a height of the canopy light 70, and h a height of the fire prevention wall 60. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a gas station canopy lamp, and more particularly to a gas station canopy lamp using a semiconductor light emitting element such as a light emitting diode (LED) as a light source.

  In the petrol station site, a refueling machine for refueling gasoline and other fuels is placed in the center of the car, and a roof called a canopy supported by a column above it is about 5 to 6 meters high. Is set. An illuminating device called a canopy lamp that mainly illuminates the lower portion of the canopy is provided on the lower surface of the canopy, and an HID lamp or the like is used as a light source.

  By the way, fire pits are installed on the outer periphery of the gas station site to prevent the spread of fire. If light from a canopy light leaks outside the site, May cause light pollution (pollution caused by excessive light). The conventional canopy lamp does not strictly control the light distribution as the lighting device itself. Therefore, as measures against light pollution, the brightness (luminance) of the canopy lamp is reduced, or a member such as a hood is added to the canopy lamp. The method of limiting the illumination range is taken.

  However, if the brightness of the canopy lamp is reduced as in the prior art, there is a problem that the lower part of the canopy becomes dark and the effect of attracting customers decreases. Moreover, when a member such as a hood is added to the canopy lamp to limit the illumination range, the configuration is complicated and the number of parts is increased, and maintenance work such as lamp replacement, cleaning, and inspection takes time. there were.

  The present invention has been made in view of such circumstances, and can illuminate the lower part of the canopy and its surroundings sufficiently brightly without causing light pollution to neighboring residents, etc., and has a simple configuration and maintenance. The object is to provide a canopy lamp for a gas station that is easy to work with.

In order to achieve the above object, a canopy lamp of a gas station according to claim 1 is installed in a canopy of a gas station, and is a canopy lamp using a semiconductor light emitting element as a light source. A canopy lamp installed in the canopy, where L is the shortest horizontal distance to the fire pit installed on the outer periphery, H is the height of the canopy lamp from the ground, and h is the height of the fire pit from the ground. The directivity angle Θ of
θ = arctan { L / (H−h) }
Angle below der which is obtained by is, the lighting canopy has a single lens, the lens is first emit light emitted from the semiconductor light emitting element after being reflected once within the lens A first reflecting surface, and a second reflecting surface that is provided outside the first reflecting surface and reflects the light emitted from the semiconductor light emitting element once inside the lens, and then emits the light. It is characterized that you form a light distribution of the directional angle Θ light emitted from the light emitting element through only the lens.

  According to the present invention, since the directivity characteristic of the canopy lamp itself is prevented from leaking from the fire pit to the outside, the lower part of the canopy can be illuminated sufficiently brightly without causing light damage to neighboring residents. Moreover, since an additional member such as a hood that limits the irradiation range is not used, the configuration is simple, and maintenance work can be easily performed.

Further , according to the present invention, the configuration of the optical system of the canopy lamp is simple, and the canopy lamp can be downsized.

  According to the present invention, the lower part of the canopy can be illuminated sufficiently brightly without causing light pollution to neighboring residents and the like, and the configuration is simple and the maintenance work is facilitated.

Outline view showing the structure of the gas station site The figure which showed the light distribution pattern in the illumination intensity distribution (the height of a canopy lamp is about 6.0 m, the observation height is about 1.5 m) illuminated by the canopy lamp. Sectional drawing which showed the vertical cross section containing the position of the canopy lamp with the shortest distance with a fire barrier, and the position of the fire barrier 60 with the shortest distance. The perspective view of the water-cooling type LED lighting apparatus of this Embodiment. The figure of the arrow A direction of FIG. The figure of the arrow B direction of FIG. The CC sectional view taken on the line of FIG. The DD sectional view taken on the line of FIG. EE sectional view taken on the line of FIG. FIG. 5 is an exploded perspective view of the water-cooled LED lighting device of FIG. 4. The basic block diagram of the water cooling unit of the water cooling type LED lighting apparatus of FIG. Sectional drawing (XZ top view) which showed the shape of the lens. The expanded sectional view which expanded a part of lens (XZ top view). Figure. The block diagram which showed the structure of the personal computer. The flowchart which showed the process sequence by CPU of the personal computer for calculating the shape of a lens. The flowchart which showed the content of the process of step S20 of FIG. The figure used for description of a virtual focus. The figure used for description of the initial incidence point. The figure used for description of the flowchart of FIG. The figure used for description of the flowchart of FIG. The figure used for description of how to determine control curve β (α). The figure which showed an example of control curve (beta) ((alpha)).

  Hereinafter, with reference to an accompanying drawing, a form for carrying out a canopy lamp of a gas station concerning the present invention is explained in detail.

  FIG. 1 is an external view simply showing the configuration of a petrol station site. As shown in the figure, in the site of the gas station 50, refueling machines 52, 52,... For supplying fuel such as gasoline to a car are arranged in a substantially central portion, and called a canopy 54 above the refueling machines 52, 52,. The roof is supported by the columns 56 and 56 and is installed at a height of about 5 to 6 m.

  In addition, on the site, there are buildings 58 etc. where staff rooms and service rooms used by employees and visitors are provided, and on the outer periphery of the site, there is a part facing the road that serves as the entrance of vehicles etc. Except for that, a fire pit 60 is provided. The main purpose of the fire pit 60 is to prevent the spread of fire when a fire occurs inside or outside the gas station 50.

  Further, on the lower surface side of the canopy 54, canopy lights 70, 70,... For illuminating the lower side of the canopy 54 are installed. In the present embodiment, an LED illumination device using an LED as a light source is used as the canopy lamp 70. Although the configuration of the LED lighting device will be described later, there are advantages such as less heat generation, low power consumption, thinness, and light weight compared to a HID lamp or the like generally used as a canopy lamp. In particular, according to the LED lighting device described later, the optical system is configured by only one thin lens that serves as a light source and an LED as a light source for a desired light distribution. It has been realized. In addition, it is good also considering not only LED but other types of semiconductor light-emitting devices, such as a laser diode (LD), as a light source.

  FIG. 2 shows the illuminance distribution below the canopy 54 illuminated by the canopy lamps 70, 70,... (LED lighting device) of the present embodiment. As shown in the figure, the center directly below the canopy 54 is the brightest, about 600 Lux, and the light distribution is such that the illuminance gradually decreases toward the periphery.

  Although not shown in the figure, the illumination range of the canopy lights 70, 70,... Is limited so that light from the canopy lights 70, 70,. .

FIG. 3 shows a vertical cross section including the position of the canopy lamp 70 having the shortest horizontal distance from the fire pit 60 and the position of the fire retardant 60 having the shortest distance in the gas station 50 as shown in FIG. FIG. As shown in the figure, the height of the canopy lamp 70 from the ground is H, the height of the fire fence 60 from the ground is h, and the horizontal distance (shortest horizontal distance) between the canopy lamp 70 and the fire fence 60 is L. To do. If the angle between the straight line connecting the canopy lamp 70 and the upper end of the fire pit 60 and the straight line in the vertical direction is θ (referred to as the maximum allowable irradiation angle θ), θ is the following equation (1):
θ = arctan { L / (H−h) } (1)
Is required.

  Based on this, each canopy lamp 70 is designed so that the directivity angle Θ becomes the maximum allowable irradiation angle θ calculated by the above equation (1) or less than the maximum allowable irradiation angle θ. The directivity angle Θ indicates an angle (half-value angle) at which the luminous intensity is halved with respect to the luminous intensity of the front. Thereby, the light from the canopy lamp 70 is prevented from leaking to the outside of the fire pit 60.

  Since the maximum allowable irradiation angle θ of the above formula (1) varies depending on the gas station, a canopy lamp (LED lighting device) having an appropriate directivity angle Θ is manufactured according to the maximum allowable irradiation angle θ of each gas station. Alternatively, several types of canopy lamps (LED lighting devices) with different directivity angles Θ have been commercialized, and the type of canopy lamp used at each gas station is optimal depending on the maximum allowable irradiation angle θ at each gas station. You may make it selectable.

  Next, the configuration of the LED lighting device (water-cooled LED lighting device) used for the canopy lamp 70 and the like will be described. 4 is a perspective view of the water-cooled LED lighting device of the present embodiment, FIG. 5 is a view in the direction of arrow A in FIG. 4, FIG. 6 is a view in the direction of arrow B in FIG. -C sectional view, FIG. 8 is a sectional view taken along the line DD of FIG. 6, FIG. 9 is a sectional view taken along the line EE of FIG. 6, and FIG. 10 is an exploded perspective view of the water-cooled LED lighting device of this embodiment. FIG. 11 is a basic configuration diagram of a water-cooling unit of the water-cooled LED lighting device of the present embodiment.

  The water-cooled LED lighting device 1 (hereinafter referred to as the LED lighting device 1) according to the present embodiment includes a light source unit 3 and a control circuit unit 4 inside a rectangular box-shaped housing 2, as shown in FIGS. And the water cooling unit 5 is incorporated.

  The housing 2 is made of a resin such as PC or a metal such as aluminum. As shown in FIG. 4, an air inlet 6 composed of a plurality of longitudinally long slits is formed on the peripheral surface of the housing 2. Is formed with an exhaust port 7 formed of a plurality of fan-shaped slits. The lower surface of the housing 2 is open, and the light source unit 3 is fitted and fixed in the opening.

  As shown in FIGS. 7 to 10, the light source unit 3 includes a plurality of {9 in the illustrated example] metal substrates 9 formed by mounting LEDs 8 (see FIG. 11) as light sources, and these metal substrates 9. A rectangular plate-like base 10 to be attached and a rectangular plate-like transparent resin lens 11 fitted into the lower surface opening of the housing 2 are included. In FIG. 10, reference numeral 12 denotes a cable connector.

  In the present embodiment, the nine metal substrates 9 on which the LEDs 8 are mounted are arranged in a matrix of three rows and columns, and correspondingly, the base 10 made of aluminum die-casting also has the same number of pedestals as the LEDs 8. 10a (see FIG. 7 and FIG. 9) is integrally projected in a matrix form of three rows in length and width. Each metal substrate 9 is fixed by screwing each pedestal 10 a of the base 10 via a rectangular heat conductive sheet 13. In addition, each heat conductive sheet 13 is comprised by the silicon | silicone etc. with insulation and high heat conductivity.

  Further, as shown in FIG. 10, the control circuit unit 4 incorporates a circuit board 15 on which various electronic components (not shown) are mounted inside a rectangular box-shaped circuit case having an open bottom surface. The opening is covered with a rectangular plate-shaped cover 16. Here, the circuit case 14 is formed by aluminum die casting or the like having a high thermal conductivity, and a large number of heat radiation pins 17 constituting a heat radiation portion are integrally projected on the upper surface thereof. A circuit board 15 is in close contact with the inner front surface of the circuit case 14 via a rectangular heat conductive sheet 18 made of silicon or the like having high insulation and thermal conductivity. Note that an O-ring 19 is interposed at the joint between the circuit case 14 and the cover 16, and the inside of the circuit case 14 is sealed by the sealing action of the O-ring 19, and water or the like from the outside into the circuit case 14. Intrusion is prevented.

  As shown in FIGS. 7 to 11, the water cooling unit 5 has a water cooling jacket 20 that is a heat exchanger and heat of the cooling water that has received heat in the water cooling jacket 20 and is heated to the outside air (cooling air). A radiator 21 for cooling by replacement, a fan 22 for supplying cooling air to the radiator 21, a circulation pump 23 for circulating the cooling water in a closed loop circulation path, and a reserve tank 24 for storing the cooling water. 22 is disposed above the radiator 21 so as to face it.

  By the way, the water cooling jacket 20 is formed in a hollow rectangular plate shape, and a cooling water passage is formed therein as shown in FIGS. As shown in FIGS. 8 and 10, an inlet pipe 25 into which cooling water flows after being cooled by heat exchange with the outside air (cooling air) in the radiator 21 is provided on one end of the water cooling jacket 20. An outlet pipe 26 is provided to discharge the cooling water whose temperature has been increased by receiving heat in the jacket 20.

  And in this Embodiment, as shown in FIG.7 and FIG.9, the water cooling jacket 20 is horizontally arrange | positioned at the bottom part of the lower part in the housing 2, and this control circuit unit is put up and down across this water cooling jacket 20. 4 and the light source unit 3 are arranged. Here, the light source unit 3 arranged on the lower surface side of the water cooling jacket 220 has its base 10 in close contact with the lower surface of the water cooling jacket 20 via a rectangular heat conductive sheet 27. In the present embodiment, the heat conductive sheet 27 is made of silicon or the like having high insulation and thermal conductivity.

  Further, the control circuit unit 4 is arranged on the upper surface side of the water cooling jacket 20 with the cover 16 being in close contact with the upper surface of the water cooling jacket 20. In this embodiment, an antifreeze liquid obtained by mixing water with propylene glycol is used as the cooling water.

  On the other hand, as shown in FIGS. 7 and 9, the radiator 21 and the fan 22 are disposed in the upper portion of the housing 2 apart from the water cooling jacket 20, and a space portion is provided between the water cooling jacket 20 and the radiator 21. S is formed, and the control circuit unit 4, the circulation pump 23, and the reserve tank 24 are arranged in the space S. Specifically, a gate-shaped chassis 28 is erected on the water cooling jacket 20, and the control circuit unit 4 is disposed in a space surrounded by the chassis 28, and the circulation pump 23 and the reserve tank 24 are disposed on the chassis 28. Is installed.

  Here, as shown in FIGS. 8 and 11, a pipe (rubber hose) 29 rising upward from the outlet pipe 26 of the water cooling jacket 20 is connected to the inlet pipe 30 of the radiator 21, and from the outlet pipe 31 of the radiator 21. The extending pipe (rubber hose) 32 extends downward and is bent at a substantially right angle and connected to the suction side of the circulation pump 23. A pipe (rubber hose) 33 extending from the discharge side of the circulation pump 23 is connected to the inlet side of the reserve tank 24 as shown in FIG. Is connected to the inlet pipe 25 of the water cooling jacket 20. As described above, the water cooling jacket 20, the radiator 21, the circulation pump 23, and the reserve tank 24 are connected by the pipes (rubber hoses) 29 and 32-34 to form a circulation path that forms an open loop. Circulation provides the required cooling action.

  When the LED lighting device 1 configured as described above is activated and power is supplied to the light source unit 3, the control circuit unit 4, and the water cooling unit 5, a plurality of light source units 3 (9 in the present embodiment) are provided. LED 8 emits light, and the light passes through the lens 11 and is irradiated downward in FIG. 4 to illuminate the front. However, the LED 8 of the light source unit 3 and various electronic components (non-defective parts) of the control circuit unit 4 are illuminated. The light source unit 3 and the control circuit unit 4 are heated and the temperature rises as it is.

  However, in this embodiment, the water cooling unit 5 is driven simultaneously, and the light source unit 3 and the control circuit unit 4 are forcibly cooled by the cooling water circulating in the circulation path shown in FIG. It can be suppressed.

  That is, the cooling water circulating through the circulation path by the circulation pump 23 receives the heat generated in the light source unit 3 and the control circuit unit 4 in the water cooling jacket 20 to cool the light source unit 3 and the control circuit unit 4 and receive the heat. The cooling water whose temperature has been increased is introduced into the radiator 21 through the pipe 29.

  On the other hand, when the fan 22 is rotationally driven by a motor (not shown), the outside air is sucked into the housing 2 from the side as the cooling air from the intake port 6 formed in the peripheral surface of the housing 2, and this cooling air is supplied to the water cooling jacket. 20 flows upward through a space S formed between 20 and the radiator 21, passes through the radiator 21 in the process, and is discharged to the outside through the exhaust port 7 opened on the upper surface of the housing 2. In the radiator 21, the heat of the cooling water is radiated to the outside by the cooling air passing through the radiator 21 to cool the cooling water, and the cooling liquid water whose temperature has decreased is sucked into the circulation pump 23 through the pipe 32. Is done.

  The cooling water sucked into the circulation pump 23 is boosted and then sent out from the circulation pump 23 through the pipe 33 to the reserve tank 24, a part of which is stored in the reserve tank 24, and the remaining cooling water is stored in the reserve tank 24. Is introduced into the water-cooling jacket 20 through the pipe 34 and used for cooling the light source unit 3 and the control circuit unit 4. Then, the above action (cooling cycle) is continuously repeated, and the light source unit 3 and the control circuit unit 4 are forcibly cooled by the cooling water flowing through the water cooling jacket 20, and their temperature rise is suppressed to a certain value or less.

  In the present embodiment, since the control circuit unit 4 and the light source unit 3 are disposed above and below the water cooling jacket 20, the cooling water circulates in the closed loop circulation path by the circulation pump 23, thereby causing the water cooling jacket 20. The light source unit 3 and the control circuit unit 4 arranged on both sides are simultaneously forcibly cooled by the cooling water. As a result, the temperature rise of the light source unit 3 and the control circuit unit 4 is suppressed, and high output of the LED lighting device 1 is realized.

  In the present embodiment, the lower surface of the control circuit unit 4 is brought into close contact with the water-cooling jacket 20, and a large number of heat radiation pins 17 constituting the heat radiation portion are provided on the upper surface, so that the control circuit unit 4 is forcibly cooled by the cooling water. At the same time, since heat is naturally radiated from the heat radiating pins 17, the control circuit unit 4 is efficiently cooled, and the temperature rise is more efficiently suppressed.

  Furthermore, in the present embodiment, the entire surface of the light source unit 3 is in close contact with the lower surface of the water-cooling jacket 20 via the heat conductive sheet 27 having a high thermal conductivity. The light source unit 3 is efficiently cooled by the cooling water flowing through the water cooling jacket 20.

  In the present embodiment, since the control circuit unit 4 is disposed in the space S formed between the water cooling jacket 20 and the radiator 21 of the water cooling unit 5, the cooling air introduced into the housing 2 by the fan 22 is The control circuit unit 4 is forcibly cooled by flowing through the space S, and the control circuit unit 4 that is forcibly cooled by the cooling water is further efficiently cooled, and the temperature rise can be effectively suppressed.

  Next, a method for designing (calculating) the shape of the lens in the light source unit 3 of the LED illumination device 1 will be described in detail. As described above, in the optical section of the light source unit 3, as shown in FIGS. 7 to 10, LEDs 8 (refer to FIG. 11) as light sources are arranged in a matrix of three rows and columns, and in front of them are rectangular plate shapes. A transparent resin lens 11 is disposed. The lens 11 is for illumination that collects light emitted from the LEDs 8 and emits light of a predetermined light distribution pattern (illuminance distribution) corresponding to the positions of the LEDs 8 arranged in a matrix of three rows and columns. A lens 11A is formed.

  In the following, a method for calculating the shape of the lens 102 will be described with an arbitrary one LED 8 as the light source 100 and the illumination lens 11A disposed facing the LED 8 as the lens 102 as shown in FIG. The light source 100 is not limited to an LED, and may be another type of semiconductor light emitting element such as a laser diode (LD).

  First, in the present embodiment, for ease of explanation, optical characteristics such as illuminance distribution of the light source 100 are symmetric with respect to rotation at an arbitrary angle with the optical axis O as the rotation axis, and the lens 102 is interposed. The light distribution pattern formed in this way and the shape of the lens 102 are also symmetric with respect to rotation at an arbitrary angle with the optical axis O as the rotation axis. In a three-dimensional space composed of X, Y, and Z axes (coordinate axes) orthogonal to each other, the position of the light source 100 is set as the position of the origin of the XYZ coordinates, the optical axis O is set as the Z axis, and the optical unit on the XZ plane is Only the range in which the X coordinate is 0 or more will be described mainly while illustrating the cross section.

  As shown in FIG. 12, the lens 102 includes a surface OL formed in a convex shape and a back surface BL configured by a combination of a plurality of surfaces IL1 to IL3, RL1, and RL2.

  As shown in a partially enlarged view of FIG. 13, an angle formed by light (ray r) emitted from the light source 100 and the Z axis (optical axis O) is referred to as a light source emission angle, and the angle is α. The back surface BL has a first transmission surface IL1 that allows light having a light source emission angle α in an angle range α1L (= 0 °) ≦ α <α1H to enter (transmit) into the lens 102 out of the light emitted from the light source 100. , A second transmission surface IL2 that allows light in an angle range α2L ≦ α <α2H to enter the lens 102, and a third transmission surface IL3 that allows light in an angle range α3L ≦ α <α3H to enter (transmit) in the lens 102. And is formed from. Note that α1H = α2L and α2H = α3L.

  As shown in FIG. 12, the light (light ray r1) that has entered the lens 102 from the first transmission surface IL1 travels straight (does not reflect) in the lens 102 and is directly emitted from the surface OL. On the other hand, the light (light rays r2, r3) that has entered the lens 102 from the second transmission surface IL2 and the third transmission surface IL3 are respectively reflected by the lens 102 by the first reflection surface RL1 and the second reflection surface RL2 that constitute the back surface BL. After being reflected once inside, it is emitted from the surface OL. The first reflection surface RL1 and the second reflection surface RL2 are subjected to surface treatment so that light is totally reflected inside.

  By using such a lens 102, the light emitted from the light source 100 in an angle range of about 180 ° is used as illumination light without using a member other than the lens 102 such as a reflector, so that the configuration and the manufacture are possible. In addition, the light source 100 and the lens 102 are arranged close to each other, and the lens 102 is thin, so that the optical part of the LED lighting device 1 can be reduced in size. The size can be reduced.

  The number of reflection surfaces such as the first reflection surface RL1 and the second reflection surface RL2 can be changed, and is not limited to the case of having two reflection surfaces as shown in FIG.

  Next, a method for calculating the shape of the lens 102 will be described. An arithmetic processing unit such as a personal computer is used to calculate the shape of the lens 102, and the shape of the lens 102 is calculated by starting the lens design software (program) according to the present embodiment installed in advance. For this purpose, an arithmetic process is performed.

  As shown in FIG. 14, the personal computer 150 includes a CPU (Central Processing Unit) 152, a ROM (Read Only Memory) 154, a RAM (Random Access Memory) 156, a host bus 158, a bridge 160, an external bus 162, and the like. , An interface 164, an input device 166, an output device 168, a storage device (HDD) 170, a drive 172, and the like.

  The CPU 152 functions as an arithmetic processing unit and a control unit, operates according to various programs, and controls each unit in the PC 150. The CPU 152 executes various processes according to a program stored in the ROM 154 or a program loaded from the storage device 170 to the RAM 156. The ROM 154 stores programs and calculation parameters used by the CPU 152 and also functions as a buffer for reducing access from the CPU 152 to the storage device 170. The RAM 156 temporarily stores programs used in the execution of the CPU 152, parameters that change as appropriate during the execution, and the like. These are connected to each other by a host bus 158 including a CPU bus. The host bus 158 is connected to an external bus 162 such as a peripheral component interconnect / interface (PCI) bus via the bridge 160.

  The input device 166 includes, for example, operation means such as a mouse, a keyboard, a touch panel, a button, a switch, and a lever, and an input control circuit that generates an input signal and outputs it to the CPU 152. The output device 168 includes, for example, a liquid crystal display (LCD) device, a CRT (Cathode Ray Tube) display device, a display device such as a lamp, and an audio output device such as a speaker.

  The storage device 170 is a data storage device configured as an example of a storage unit of the personal computer 150. For example, a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or a magneto-optical device Consists of storage devices and the like. The storage device 170 stores programs executed by the CPU 152 and various data.

  The drive 172 is a storage medium reader / writer, and reads information recorded on a removable recording medium 174 such as a mounted magnetic disk, optical disk, magneto-optical disk, or semiconductor memory, and outputs the information to the RAM 156. Further, the drive 172 can also write information on the writable removable recording medium 174 attached. The removable recording medium 174 is, for example, a DVD medium, an HD-DVD medium, a Blu-ray medium, a compact flash (registered trademark) (CompactFlash: CF), a memory stick, an SD memory card (Secure Digital memory card), or the like.

  In the personal computer 150 configured as described above, when the designer activates the lens design program according to the present embodiment using the input device 166, the CPU 152 reads the program from the storage device 170. Then, the following lens design processing according to the program is executed.

  Next, a processing procedure by the CPU 152 of the personal computer 150 for calculating the shape of the lens 102 will be described with reference to the flowcharts of FIGS.

  The CPU 152 sets the position of the light source 100 to the position of the origin of the XYZ coordinates and sets the optical axis O as the Z axis in a three-dimensional space composed of X, Y, and Z axes (coordinate axes) as shown in FIG. Further, the shape of the surface OL of the lens 102 is determined by the designer and designated by input from the input device 166, and the CPU 152 sets the shape of the designated surface OL on the XYZ coordinates (step S10 in FIG. 15). In addition, what the operator such as the designer inputs from the input device 166 and designates to the CPU 152 like the data of the shape of the surface OL is directly input from the input device 166 by the designer at the time of the arithmetic processing of the CPU 152. Instead, data created in advance and recorded and stored in the storage device 170 or the removable recording medium 174 may be acquired from the storage device 170 or the removable recording medium 174. In the following, the data designated by the designer is given by any means such as the input device 166, the storage device 170, and the removable recording medium 174 as long as the CPU 152 can acquire the data. However, it is not specified what kind of means is given.

  Next, the CPU 152 sets a control curve β (α) indicating the relationship between the light source emission angle α and the lens emission angle β based on the designation of the designer (step S12 in FIG. 15).

  Here, as shown in FIG. 13, an angle formed between light (light ray r) emitted from the light source 100 in a certain direction and the Z axis (optical axis O) is referred to as a light source emission angle α, and the light source emission angle from the light source 100 is the same. Light or light emitted in the direction of α is referred to as light or light having a light source emission angle α. The angle formed between the light (ray r ′) emitted from the surface OL of the lens 102 in a certain direction and the Z axis (optical axis O) is referred to as a lens emission angle β, and the lens emission from the surface OL of the lens 102 The light or light beam emitted in the direction of the angle β is referred to as light or light beam at the lens emission angle β.

  The control curve β (α) is a curve representing how many times the light with the light source exit angle α is converted into light with the lens exit angle β by refraction and reflection by the lens 102, and the control curve β (α) The shape of the lens 102 is calculated so as to satisfy the relationship. The designer determines the control curve β (α) so that a desired light distribution (light distribution pattern) as the LED illumination device 1 is obtained by the light emitted from the lens 102, and the control curve β (α) is determined. Specify to CPU152. A procedure for determining the control curve β (α) will be exemplified later.

  Next, the CPU 152 calculates the number (Nmax) of the calculation surfaces whose shape is to be calculated as the surface forming the back surface BL of the lens 102 based on the designation of the designer, and the light source of light from the light source 100 incident on each calculation surface. An angle range related to the emission angle α is set (step S14 in FIG. 15). Here, from the calculation surface closer to the origin with respect to the X axis, the first calculation surface BL1, the second calculation surface BL2,..., And the Nth (1 ≦ N <Nmax) calculation surface is the Nth calculation surface BLN. It shall represent. An angle range related to the light source emission angle α of light incident on the Nth calculation surface BLN is represented by αNL ≦ α <αNH.

  When the back surface BL having the shape shown in FIGS. 12 and 13 is formed, as the calculation surfaces, the first transmission surface IL1, the first reflection surface RL1, and the second reflection surface RL2 are the first calculation surface BL1 and the second calculation surface. This corresponds to the surface BL2 and the third calculation surface BL3, and the designer designates 3 as the number Nmax of calculation surfaces. In the present embodiment, regardless of the number Nmax of calculation surfaces, only the first calculation surface B1 with N = 1 is always a transmission surface such as the first transmission surface IL1, and the calculation surface with N ≧ 2 is It is assumed that the reflecting surfaces are the first reflecting surface RL1 and the second reflecting surface RL2.

  On the other hand, in FIGS. 12 and 13, the second transmission through which the light from the light source 100 passes before entering the first reflection surface RL1 (second calculation surface BL2) or the second reflection surface RL2 (third calculation surface BL3). The surface IL2 and the third transmission surface IL3 are not set as calculation surfaces. That is, the transmission surface set as the calculation surface is only the first transmission surface IL1 (first calculation surface BL1), and the other transmission surface (the transmission surface through which the light from the light source 100 passes before entering the predetermined reflection surface). Is not set as a calculation plane. The transmission surfaces other than the first transmission surface IL1 are surfaces that refract the light from the light source 100 to the corresponding reflection surface, such as a surface that refracts the light from the light source 100 in a direction in which the formation of the reflection surface is difficult. The light source emission angle α incident on the reflection surface need not be a surface that converges meaninglessly, and can be designed relatively freely (for example, transmission surfaces other than the first transmission surface BL1 are XZ planes). The surface may simply be a straight line in FIG. For this reason, the information on the shape of the transmissive surface is appropriately set when necessary, the details of the shape may not be described, the designer may specify them, or the CPU 152 automatically sets them. It may be set as a combination of both.

  In addition, the angle range αNL ≦ α <αNH related to the light source emission angle α of the light incident on the Nth calculation surface BLN is an angle range of light that is effectively used among the light emitted from the light source 100 in each angle direction. -Αmax is divided by the number Nmax of calculation surfaces to determine an angle range related to the light source emission angle α of light incident on each calculation surface from the first calculation surface BL1 to the Nmax calculation surface BLNmax, and αNH = α (N + 1) L (except when N is Nmax).

  When the back surface BL having the shape as shown in FIGS. 12 and 13 is formed, as shown in FIG. 13, the angle range of the light source emission angle α of the light incident on the first calculation surface BL1 is 0 ° (α1L in the drawing). ) ≦ α <α1H, and the light source emission angle α of the light incident on the second calculation surface BL2 is in the range of α2L ≦ α <α2H in the drawing and is incident on the third calculation surface BL3. The angle range of the light source emission angle α of the light is α3L ≦ α <α3H in the drawing.

  In the present embodiment, these angle ranges are specified by the designer at an early stage together with the number Nmax of calculation surfaces. However, with respect to a certain calculation surface, control is performed for light in the angle range specified by the designer. There is a possibility that the shape cannot be formed so as to satisfy the relationship of the curve β (α). In addition, since it is not necessary to set the angle ranges for all the calculation surfaces in the initial stage, the shape of the calculation surface is calculated in order from the first calculation surface BL1 to the Nmax calculation surface BLNmax in the following processing. Under certain assumptions, information on the required angle range may be set or corrected as appropriate. At this time, the number Nmax of the calculation surfaces can be corrected according to the set or corrected angle range, or the specification itself of the number Nmax of calculation surfaces can be made unnecessary (the shape of a certain calculation surface) After calculating, it is not necessary to specify the number Nmax of calculation planes in a method such as adding one calculation plane if necessary.

  As described above, in the present embodiment, the lens 102 is premised on having a shape that is symmetric with respect to rotation at an arbitrary angle with the Z axis (optical axis O) as the rotation axis. If the shape (line shape) of the back surface BL of the lens 102 in the range of X ≧ 0 in the XZ plane is obtained, the surface formed by rotating the line shape with respect to the Z axis is the shape of the entire back surface BL of the lens 102. I want. Therefore, in the present embodiment, only the procedure for calculating only the shape of the back surface BL in the range of X ≧ 0 on the XZ plane is shown. Even if the lens 102 does not have such symmetry, for example, the shape (line shape) of the back surface BL of the lens 102 in an arbitrary cross section is obtained by the same procedure as in the present embodiment. Can be connected three-dimensionally to obtain the three-dimensional shape of the back surface BL.

  Next, as shown in FIG. 17, the CPU 152 assumes that the entire rear side (light source 100 side) of the surface 102 of the lens 102 is the medium of the lens 102 (from the atmosphere to the inside of the lens 102 through the surface OL. The light that enters the lens medium is assumed to travel permanently in the lens medium), and parallel light whose angle β with the Z-axis (optical axis O) forms an angle β from the front side (the positive side of the Z-axis) to the surface. The position (coordinates) of the focal point (imaging point) when incident on the OL is obtained using a method such as ray tracing (step S16 in FIG. 15). Here, the coordinate of the focal point of the parallel light incident at an angle β with respect to the Z axis is S (β), and is referred to as a virtual focal point S (β).

  The virtual focal point S (β) is also a virtual light source that emits light having a lens emission angle β from the surface OL of the lens 102, and the locus of the light ray r incident on the surface OL of the lens 102 from within the lens 102 as shown in FIG. When the virtual focal point S (β) is present on the extension line, that is, when the virtual light source is arranged at the position of the virtual focal point S (β), the trajectory of any ray emitted from the virtual light source and the ray r When the locus coincides, the light beam r is emitted from the surface OL of the lens 102 to the outside (in the atmosphere) as light having a lens emission angle β.

  As described above, the virtual focal point S (β) gives a trajectory that the light should pass through the lens 102 when the light incident on the lens 102 is emitted from the surface OL of the lens 102 as light having the lens emission angle β. Thus, when light incident from the back surface BL of the lens 102 is emitted as light having a lens emission angle β according to the control curve β (α) as described later, a trajectory that the light should pass through the lens 102 is obtained. Referenced when.

  Further, when the position (coordinates) of the virtual focal point S (β) is obtained by changing the value of the angle β, the convex surface OL as shown in FIG. 17 is on the substantially elliptical line ls on the XZ plane. The virtual focal point S (β) is detected at, and a virtual focal point group that draws a substantially elliptical line ls is formed. Accordingly, the position of the virtual focal point S (β) may be obtained discretely while changing the value of the angle β little by little, but any angle can be determined based on the positions of the plurality of virtual focal points S (β). A curve formula ls (β) of an approximate curve indicating the position of the virtual focus S (β) with respect to β is obtained, and the position of the virtual focus S (β) with respect to an arbitrary angle β is expressed by a curve formula ls (β) when necessary. You may make it obtain | require using.

  When the above initial setting process is completed, the CPU 152 proceeds to a process for actually calculating the shape of the calculation surface. First, a process of determining whether or not the condition of N ≦ Nmax (Nmax is the number of calculation planes) is satisfied with N indicating the calculation plane number being 1 (step S18 in FIG. 15). In the case of N = 1, in order to always satisfy this condition, the process proceeds to step S20, and the shape of the first calculation surface BL1 is calculated. Specific processing contents for calculating the shape will be described later. After calculating the shape of the first calculation surface BL1, N is set to N = N + 1 (N is increased by 1) (step S22), and the process returns to the determination process of step S18.

  Such a process is executed from N = 1 to N = Nmax. When N exceeds the number Nmax of calculation planes and becomes Nmax + 1, it is determined NO in step S18, and all the processes are completed.

  Next, the processing content of step S20 in FIG. 15 for calculating the shape of the Nth calculation surface BLN at the predetermined value N will be specifically described with reference to the flowchart in FIG. First, the CPU 152 sets the position (coordinates) of the initial incident point BLN (αNL) as the position at which light having the light source emission angle αNL is incident on the Nth calculation surface BLN according to the designer's specification (step S30). The light source emission angle αNL indicates the minimum angle in the angle range αNL ≦ α <αNH related to the light source emission angle α of light incident on the Nth calculation surface BLN.

  For example, when N = 1, as shown in FIG. 18, a position where light having a light source emission angle of 0 ° is incident on the first calculation surface BL1 is designated as the initial incident point BL1 (0 °). In the figure, the shape of the first calculation surface BL1 shown in FIG. 12 and the like is indicated by a dotted line, but at this stage, the shape of the first calculation surface BL1 is not determined at all, and is based on this shape. Instead of designating the position of the initial incident point BL1 (0 °), the designer designates it considering the thickness of the lens 102 and the like. However, at an arbitrary value N, the position of the initial incident point BLN (αNL) must satisfy the condition that at least the light of the light source emission angle αNL passes before reaching the surface OL, and N = 1 In addition, it is necessary to designate a position satisfying this condition as the initial incident point BLN (αNL).

  For example, when N = 2, as shown in FIG. 18, an initial incident point BL2 (α2L) is set as a position where light having a light source emission angle α2L is incident on the second calculation surface BL2. At this time, the light having the light source emission angle α2L is refracted when entering the lens 102 from the second transmission surface IL2 before entering the second calculation surface BL2. Accordingly, the position of the initial incident point BL2 (α2L) can be set by the manner of refraction at the second transmission surface IL2, but the designer has designated the position of the initial incident point BL2 (α2L), for example. Thereafter, the shape of the second transmission surface IL2 may be set so that light having the light source emission angle α2L is incident on the initial incident point BL2 (α2L), or after the shape of the second transmission surface IL2 is set. Then, the position through which light having the light source emission angle α2L refracted by the second transmission surface IL2 passes is calculated, and the position of the initial incident point BL2 (α2L) is set to one of the passing positions according to the instructions of the designer. May be. In the case of N = 3, similarly to the case of N = 2, in consideration of refraction at the third transmission surface IL3, the light having the light source emission angle α3L is incident on the third calculation surface BL3 as shown in FIG. The initial incident point BL3 (α3L) is set as the position to be operated, and when N ≧ 4, the initial incident point BLN (αNL) is set similarly to N = 2 and 3.

  When the initial incident point BLN (αNL) of the Nth calculation surface BLN is set in this way, the CPU 152 first sets α0 = αNL as the value α0 of the light source emission angle α, and the light is the Nth calculation surface. An incident point BLN (α0) indicating a position incident on BLN is set as an initial incident point BLN (αNL) (step S32).

  And CPU152 repeats the process of step S34-step S42. As a result, while increasing the light source emission angle α0 by Δα from αNL, incident points BLN (α0) at which light of each light source emission angle α0 is incident on the Nth calculation surface BLN are sequentially obtained, and these incident points BLN (α0). The shape of the Nth calculation surface BLN is finally calculated according to the position of.

  Assume that an incident point BLN (α0) where light having a predetermined light source emission angle α0 is incident on the Nth calculation surface BLN has been obtained. FIG. 19 illustrates a state where an incident point BL1 (α0) where light having a predetermined light source emission angle α0 is incident on the first calculation surface BL1 is obtained when N = 1. First, the CPU 152 sets the virtual focal point S (β0) corresponding to the incident point BLN (α0) and the lens emission angle β (α0) = β0 associated with the light source emission angle α0 by the control curve β (α). A straight line M0 is obtained (step S34). The straight line M0 indicates the locus of the light ray in the lens 102 for the light ray r1 incident on the incident point BLN (α0) to be emitted at the lens emission angle β (α0).

  Next, after the light having the light source emission angle α0 is incident on the incident point BLN (α0) of the Nth calculation surface BLN, the CPU 152 moves the light in the direction of the straight line M0 (so as to have a locus matching the straight line M0). Surface direction of the Nth calculation surface BLN at the incident point BLN (α0) (normal direction γ (α0) in the present embodiment) so as to be refracted (when N = 1) or reflected (when N ≧ 2). Is calculated (step S36). That is, a tangential plane P (α0) in contact with the Nth calculation surface BLN at the incident point BLN (α0) is obtained. If the N-th calculation surface BLN has the surface direction calculated here at the incident point BLN (α0), the light with the light source emission angle α0 is converted into the lens emission angle β (α0) according to the control curve β (α). ) Light from the lens 102.

  More specifically, at the incident angle θ1 when the light having the light source emission angle α = α0 is incident on the incident point BLN (α0) of the Nth calculation surface BLN and the incident point BLN (α0) of the Nth calculation surface BLN. The refraction angle θ2 (when N = 1) or the reflection angle θ2 (when N ≧ 2) of the light incident and refracted or reflected in the direction of the straight line M0 is the incident angle θ1 and the refraction angle θ2 or reflection angle θ2. The normal direction γ (α0) (tangential plane P (α0)) of the Nth calculation surface BLN at the incident point BLN (α0) is obtained so as to satisfy a predetermined optical condition that defines The normal direction γ (α0) is, for example, an angle formed between the normal line of the Nth calculation surface BLN and the Z axis (optical axis O) at the incident point BLN (α0).

In the case of N = 1, as shown in FIG. 19, a tangent plane P (α0) whose normal direction γ (α0) is unknown is assumed at the incident point BL1 (α0), and a light ray r1 having a light source emission angle α = α0 is incident. The incident angle θ1 when incident on the tangential plane P (α0) at BL (α0) and the refraction angle θ2 of the ray r2 incident on the incident point BL1 (α0) and refracted in the direction of the straight line M0 are expressed by the following equations. Snell's law,
sinθ1 / sinθ2 = n2 / n1 (where n1 and n2 represent the refractive index of the atmosphere (n1) and the refractive index of the lens medium (n2), respectively, with respect to vacuum)
The normal direction γ (α0) of the tangent plane P (α0) is calculated so as to satisfy The normal direction γ (α0) calculated thereby is the normal direction of the first calculation surface BL1 at the incident point BL1 (α0), and the tangential plane P (α0) is the first calculation surface at the incident point BL1 (α0). It is a tangential plane of BL1.

In the case of N = 2, as shown in FIG. 20, assuming a tangent plane P (α0) whose normal direction γ (α0) is unknown at the incident point BL2 (α0), a light beam r1 having a light source emission angle α = α0 is incident. The incident angle θ1 when incident on the tangential plane P (α0) at the point BL2 (α0) and the refraction angle θ2 of the ray r2 incident on the incident point BL2 (α0) and reflected in the direction of the straight line M0 are as follows: The law of reflection of the equation,
θ1 = θ2
The normal direction γ (α0) of the tangent plane P (α0) is calculated so as to satisfy The normal direction γ (α0) calculated thereby is the normal direction of the second calculation surface BL2 at the incident point BL2 (α0), and the tangential plane P (α0) is the second calculation surface at the incident point BL2 (α0). It is a tangential plane of BL2. The incident angle θ1 when the light beam r1 having the light source emission angle α = α0 is incident on the tangential plane P (α0) at the incident point BL2 (α0) is the incident angle of the light beam refracted by the second transmission surface IL2. It becomes.

  When N is 3 or more, the normal direction γ (α0) (tangential plane P (α0)) of the Nth calculation surface BLN at the incident point BLN (α0) is calculated in the same manner as when N = 2. .

  Next, the CPU 152 calculates the tangent plane P (α0) of the Nth calculation surface BLN at the incident point BLN (α0) obtained in step S36 as described above, in the vicinity of the incident point BLN (α0). Assuming the shape of the surface BLN, an incident point at which a light beam L1 having a light source emission angle α0 + Δα obtained by increasing the light source emission angle α0 by a minute angle Δα is incident on the tangential plane P (α0) is obtained. Then, the incident point is set as an incident point BLN (α0 + Δα) at which light having the light source emission angle α0 + Δα is incident on the Nth calculation surface BLN (step S38).

  When the incident point BLN (α + Δα) where the light having the light source emission angle α0 + Δα is incident on the Nth calculation surface BLN is obtained in this way, the value α0 of the light source emission angle α is replaced with α0 + Δα, and the light having the light source emission angle α0 is the first light. The coordinates of the incident point BLN (α0) incident on the N calculation surface BLN are replaced with the value of the incident point BLN (α0 + Δα) (step S40). Then, the processing from step S34 is repeated. If the value of the light source incident angle α0 newly set in step S40 exceeds the range of the light source emission angle α0 of the light incident on the Nth calculation surface BLN, that is, the range of αNL ≦ α0 <αNH, the process proceeds to step S42. The iterative process of step S34 to step S42 is completed by the determination process. Since the initial incident point BLN (α0) is used as the incident point BLN (αNL) of the light having the light source emission angle αNL, the value of the incident point BLN (α0) is obtained by gradually increasing the value of α0. Of the range αNL ≦ α0 <αNH of the light source emission angle α0 of light incident on the calculation surface BLN, the condition of αNL ≦ α0 is always satisfied. Therefore, in step S42, only the determination process is performed to determine whether or not the condition of α0 <αNH is satisfied.

  As described above, the incident point BLN (α) at which light having the light source emission angle α is incident on the Nth calculation surface BLN is in an angle range αNL ≦ α <αNH with respect to the light source emission angle α incident on the Nth calculation surface BLN. When calculated for the whole, the CPU 152 connects these incident points BLN (α) in the order of the size of α. At this time, the line shape connecting each incident point draws a smooth curve, and the tangential direction of the line shape at each incident point is the tangential plane in contact with each incident point obtained in step S36 on the XZ plane. Each incident point is connected using a spline curve, a Visier curve, etc. so that it may become a section direction (direction orthogonal to the normal direction of a tangent plane). As a result, the shape of the Nth calculation surface BLN (linear shape on the XZ plane) is obtained as one continuous curve (step S44). When this process ends, the process proceeds to step S22 in FIG.

  Finally, the light from the light source 100 is guided to the Nth calculation surface BLN and the Nth calculation surface BLN (N ≧ 2) obtained in the range of the XZ plane (X ≧ 0) as described above. The linear shape of the Nth incident surface (the second reflecting surface RL2, the third reflecting surface RL3,... Shown in FIG. 12, FIG. 13, etc.) is rotated around the Z axis (optical axis O), and their linear shapes are rotated. By obtaining the surface drawn by the line shape, the shape of the entire back surface BL of the lens 102 is obtained.

  In the above processing, the initial incident point set in step S30 does not necessarily have to be a position where light having the light source emission angle αNL is incident on the Nth calculation surface BLN. In the above embodiment, the designer specifies the end point of each calculation surface as the initial incident point (the incident point where the light having the smallest light source emission angle α out of the light incident on each calculation surface is incident), and the position is the base point As described above, the light beam is changed in the direction in which the light source emission angle α is increased to sequentially obtain the point (incident point) on the calculation surface and the surface direction. For example, an arbitrary point on the calculation surface is set as the initial incident point. In this case, the point on the calculation surface (incident point) is obtained by changing the light beam in both directions in which the light source emission angle α increases and decreases with the position as the base point. That's fine.

  In step S38, the incident point at which the light source emission angle α0 + Δα is incident on the Nth calculation surface BLN is the contact point at the incident point BLN (α0) at which the light source emission angle α0 is incident on the Nth calculation surface BLN. Although it is set as a point incident (intersects) on the plane P (α0), the designer sets the incident point at which the light is incident on the Nth calculation surface BLN at an arbitrary light source emission angle in the same manner as the initial incident point BLN (αNL). It may be possible to specify. In addition, the surface shape (line shape in the XZ plane) as the basic tone of the Nth calculation surface BLN is specified in advance by the designer, and the point where the light beam having the light source emission angle α intersects the linear shape as the base is incident. You may make it set as a point.

  Next, an example of the control curve β (α) representing the relationship between the light source emission angle α and the lens emission angle β will be described. The designer uses the light emitted from the light source 100 with each light source emission angle α (light beam) as many times as the lens emission angle so that a desired light distribution (light distribution pattern) can be obtained by the light emitted from the lens 102. Whether to emit light from the lens 102 at β is set by a control curve β (α). By calculating and forming the shape of the lens 102 based on the control curve β (α) as described above, the target light distribution control according to the control curve β (α) is performed by the lens 102. Various light distribution controls can be easily realized.

  First, FIG. 21 shows an example of the luminous intensity distribution (directivity distribution) with respect to the light source emission angle α (α ≧ 0) in the XZ plane of the LED light source 100. The luminous intensity distribution shown in the figure shows a general characteristic that the luminous intensity in the emission angle direction of 0 ° which is the front is the highest value, and the luminous intensity gradually decreases as the light source emission angle α increases.

  With respect to light having a light source emission angle α (α ≧ 0) in the light source 100 having such characteristics, for example, the lens emission angle β of light emitted from the lens 102 is limited within a predetermined range of 0 ° to βmax. The light distribution by the light intensity distribution is formed so that the light intensity gradually decreases as the lens exit angle β increases. For example, such a light distribution is effective for the LED lighting device 1 used for the canopy lamp 70 of the gas station described with reference to FIGS.

  As an example of how to determine the control curve β (α) in this case, first, when the luminous intensity is integrated using each angle range as an integration interval when the light source emission angle α is divided into a plurality of angle ranges, their integrated values are Each angle range is determined to be the same. In FIG. 21, when the range of the light source emission angle α (α ≧ 0) is divided in this way, 0 °, α1, α2, α3, α4,. It is shown that the angle ranges are divided into a plurality of angle ranges 0 ° to α1, α1 to α2, α2 to α3, α3 to α4,.

  At this time, for example, as shown in the control curve β (α) of FIG. 22, two adjacent angle ranges of the light source emission angle α are 0 ° to α1 and α1 to α2, α2 to α3, and α3 to α4. , ... are one set. The light in the same set of angle ranges is converted into light in the same angle range with respect to the lens emission angle β, and the light in one angle range of the two angle ranges in the same set increases as the light source emission angle α increases. The lens emission angle β is also increased, and the light in the other range is such that as the light source emission angle α increases, the lens emission angle β decreases so that light with a small light source emission angle α and light with a large light output. By superimposing, light having the same angle with respect to the lens emission angle range β is formed. As a result, uneven brightness and the like of the light source 100 are reduced.

  Further, as shown in the control curve β (α) of FIG. 22, the light in the first set of angle ranges 0 ° to α1 and α1 to α2 is changed to light in the maximum angle range 0 ° to βmax of the lens emission angle β. The second set of angle ranges α2 to α3 and α3 to α4 are converted into light having a lens emission angle β of 0 ° to β1 (<βmax), and the third set shift angle range is converted. Similarly, by narrowing the range of the lens exit angle β toward 0 °, the light from a larger set of angle ranges overlaps as the range of the lens exit angle β is closer to 0 °. It is done. Therefore, as described above, the light intensity distribution is such that the lens emission angle β of the light emitted from the lens 102 is limited to a predetermined range of 0 ° to βmax, and the luminous intensity gradually decreases as the lens emission angle β increases. This is formed by this. In this way, by superimposing the light with different light source emission angles α, luminance unevenness of the light source 100 is reduced, and the light is emitted from the lens 102 by the amount of superimposing each set of light having the same integral amount of luminous intensity. Therefore, a desired light distribution can be easily made. The method of determining the control curve β (α) described here is an example, and any method may be used. In particular, by obtaining the shape of the lens 102 as shown in the flowcharts of FIGS. 15 and 16, the lens 102 corresponding to various control curves β (α) can be easily designed, so that the designer can control the control curve β (α ) Has a high degree of freedom when deciding.

  As described above, in the above embodiment, for ease of explanation, the optical characteristics such as the illuminance distribution of the light source 100 are symmetric with respect to rotation at an arbitrary angle with the optical axis O as the rotation axis, and the lens 102 is The light distribution pattern formed through the lens 102 and the shape of the lens 102 are also symmetric with respect to rotation at an arbitrary angle with the optical axis O as the rotation axis. Also, the shape of the back surface BL of the lens 102 can be calculated by a processing procedure similar to the above processing procedure. An outline of a processing procedure for calculating the shape of the lens 102 that can be applied even when symmetry is not considered will be described in association with the flowcharts of FIGS. 15 and 16. However, the description of the process in which substantially the same processing as in FIGS.

  First, the shape (coordinates) of the surface OL of the light source 100 and the lens 102 are set on XYZ coordinates (corresponding to step S10). Then, light distribution control data β (α) indicating the relationship between the light source emission direction α and the lens emission direction β is set (corresponding to step S12). Here, in the above embodiment, the emission direction of the light emitted from the light source 100 is represented by the light source emission angle α which is an angle formed between the light emitted from the light source 100 and the Z axis (optical axis O). Here, the three-dimensional emission direction of the light emitted from the light source 100 is expressed as the light source emission direction α. Specifically, α corresponds to a three-dimensional vector. Regarding the lens emission direction β, the three-dimensional emission direction of the light emitted from the surface OL of the lens 102 is expressed as the lens emission direction β as in the light source emission direction α. The light distribution control data β (α) is data for associating the light source emission direction α and the lens emission direction β so that the designer performs desired light distribution control, and is two-dimensionally as in the above embodiment. This corresponds to the control curve β (α) when limited. At this time, the light distribution control data β (α) does not associate the light beams in the light source emission direction α and the light beams in the lens emission direction β in the same plane, but α and β in three-dimensionally different directions. Can be associated with each other.

  Next, the number Nmax of calculation surfaces and a range related to the light source emission direction α incident on the Nth calculation surface BLN (N = 1, 2,..., Nmax) are set (corresponding to step S14). Then, the position of the virtual focal point S (β) corresponding to the lens emission direction β is obtained (corresponding to step S16). That is, the surface OL is a boundary between the atmosphere and the medium of the lens 102, and parallel light traveling in the direction opposite to the predetermined direction γ in the atmosphere enters the medium of the lens 102 from the atmosphere via the surface OL, and then the lens. A virtual focus S (γ) indicating a focus position at which the parallel light converges when it is assumed that the lens 102 travels permanently is calculated. At this time, the locus of light in the lens 102 for emitting light from the surface OL in the lens emission direction β is determined by the virtual focus S (β) when the direction γ is the lens emission direction β. A virtual focus corresponding to β is S (β).

  Subsequently, the shape of each calculation surface is sequentially calculated by a process corresponding to steps S18 to S22. In the Nth calculation surface BLN in step S20, the light emitted from the light source 100 in the predetermined light source emission direction α is incident on the incident point BLN (α) where the light enters the Nth calculation surface BLN and the light source emission direction α. A straight line M0 connecting the virtual focal point S (β) with respect to the lens emission direction β associated with the light control data β (α) is obtained (corresponding to step S34). Then, a refracting surface that refracts light incident on the incident point BLN (α) in the direction of the straight line M0 or a surface direction of the reflecting surface that reflects the light (tangent plane P (α) at the incident point BLN (α)) is obtained. (Corresponding to step S36).

  Then, while changing the light source emission direction α to slightly different directions, the surface direction at the incident point where the light in that direction enters the Nth calculation surface BLN is calculated as described above. At this time, the incident point where the light in each light source emission direction enters the Nth calculation surface BLN is a position that intersects the tangent plane of the incident point already calculated in the vicinity of the position where the light in the light source emission direction passes. Set. In other words, the light source emission direction is set to a position that intersects the tangent plane of the closest light incident point (corresponding to step S38). Further, at least one of the incident points is designated by the designer as an initial incident point (corresponding to step S30).

  When the position of each point (incident point) on the Nth calculation surface BLN and the surface direction (tangent plane) at each point are calculated as described above, the surface passes through each point and is calculated at each point. The surface to be the surface direction is obtained and the shape of the Nth calculation surface BLN is calculated (corresponding to step S44).

  Note that the designer may specify the positions of the incident points where the light from the light source 100 is incident on each calculation surface, as well as the positions of a plurality of incident points. Alternatively, the surface shape as the base tone of each calculation surface may be designated in advance by the designer, and the point where the light beam having the light source emission angle α intersects the base surface may be set as the incident point. At this time, the surface in the plane direction obtained for each incident point is defined as a local surface in the vicinity of each incident point, and the local surface at each incident point is connected to form the entire calculation surface. Alternatively, a curved surface may be formed so that the surface direction of each incident point is the calculated surface shape as described above.

  As described above, the illumination device having the optical unit including the lens 102 and the light source 100 formed as described above can be used for any application, and is limited to the canopy lamp of the gas station shown in FIG. Absent. Moreover, it is not applied as an optical part of the LED illuminating device 1 of a structure as shown in FIGS. 4-11, The light source which is a semiconductor light-emitting device, The illumination lens which controls the light distribution from the light source, The lens 102 formed as described above can be applied as an illumination lens of an illumination device including the above.

DESCRIPTION OF SYMBOLS 1 ... Water cooling type LED lighting apparatus, 2 ... Housing, 3, Light source unit, 4 ... Control circuit unit, 5 ... Water cooling unit, 8 ... LED, 11 ... Lens, 11A ... Illumination lens, 50 ... Gas station, 54 ... Canopy , 60 ... Fire retardant, 70 ... Canopy lamp, 100 ... Light source, 102 ... Lens, BL ... Back surface, IL1, IL2, IL3 ... Transmission surface, RL1, RL2 ... Reflection surface, OL ... Surface

Claims (1)

In a canopy lamp installed in a gas station canopy and using a semiconductor light emitting element as a light source,
L is the shortest horizontal distance between the canopy light and the fire pit installed on the outer periphery of the gas station site, H is the height of the canopy light from the ground, and h is the height of the fire pit from the ground. Then,
The directivity angle Θ of a canopy lamp installed in the canopy is
θ = arctan { L / (H−h) }
Angle below der which is obtained by is,
The canopy lamp has a single lens,
The lens is provided on the outer side of the first reflecting surface, the first reflecting surface for emitting the light emitted from the semiconductor light emitting element after being reflected once inside the lens, and is emitted from the semiconductor light emitting element. A second reflecting surface that emits the reflected light once reflected inside the lens, and
Lighting canopy gas station, characterized that you form a light distribution of the directional angle Θ light emitted from the semiconductor light emitting element through only the lens.

Images