EP2390553A2

EP2390553A2 - LED illuminating apparatus

Info

Publication number: EP2390553A2
Application number: EP11167173A
Authority: EP
Inventors: Seki Maruyama
Original assignee: TRENTA Co Ltd
Current assignee: TRENTA Co Ltd
Priority date: 2010-05-24
Filing date: 2011-05-23
Publication date: 2011-11-30
Also published as: JP2012009856A; JP5850220B2; EP2390553A3; KR20110128757A

Abstract

There is provided an LED illuminating apparatus (10) improved in color performance and decreased in harmful effect of temperature elevation during operation even in the form of a globe-type lamp compatible to conventional screw-in type sockets. The LED illuminating apparatus including an LED light-emitting device (3a) and a base board (3b) having the LED light-emitting device (3a) mounted on one surface thereof is improved, so that main LED light-emitting elements (3A) emitting white light and additional LED light-emitting elements (3C) emitting color light are used in combination, the additional LED light-emitting elements (3C) being covered with optical regulators capable of scattering the color light, such as complex prism (11) composed of a right-angle prism (21).

Description

BACKGROUND OF THE INVENTION

1.FIELD OF THE INVENTION

The present invention relates to an illuminating apparatus using LED as a light source, improved in color performance and decreased in harmful effect of temperature elevation during operation even in the form of globe-type lamp compatible to conventional connecting tools such as screw-in type sockets.

2.DESCRIPTION OF THE RELATED ART

Light-emitting diodes (LED, below) are more and more popular recently owing to energy efficiency higher than fluorescent lamps as well as incandescent lamps. For an LED light source, too, color performance is an important problem which must be solved, like as it has been for fluorescent lamps. A number of attempts have been made for improvement thereof.
LED light sources which provide good color performance on an illuminated surface by a combination of single color LED elements emitting light of different colors are disclosed, for example, in Japanese Patent Applications Laid-open Nos. 2003-298118 and 2004-111357 .
Described in Japanese Patent Application Laid-open No. 2003-298118 is an LED light source in which five LEDs emitting light in color of shorter wave length are arranged at the center and near the border of a circle, and LEDs emitting red light are arranged at other positions within the circle in symmetry with respect to the center.
Fig.7 shows a front view toward a light-emitting surface, specifically showing an arrangement of LED elements on the LED circuit board described in Japanese Patent Application Laid-open No. 2003-298118 . LEDs 72 (indicated by circles dotted inside) emitting light of from 400 to 500 nm and that of from 500 to 600 nm in wave lengths, and LEDs 73 emitting light of from 600 to 780 nm are arranged on a base board 74 of a light source 71. The LEDs 72 emitting light of shorter wave lengths are arranged at the center and near the border of a circle, while the LEDs 73 emitting light of longer wave length are arranged at other positions within the circle in symmetry around the center.
The intensity of light emitted by such a light source composed of single-color LED elements in combination is not so high as that emitted by a light source composed of white-light emitting LEDs alone, because the intensity of light emitted by a single-color LED element is smaller compared with a white-light emitting LED element. Thus, the light source composed of a plurality of single-color elements cannot provide sufficient intensity of illumination, even if these LED elements are disposed in as high space concentration as permitted. An LED light source composed of white-light emitting LEDs in combination with single-color LED elements is described in Registered Utility Model Gazette No.3132253 as to be capable of providing sufficient intensity and improved color performance. In this light source, the LEDs are arranged in three straight lines in parallel, white-light emitting LEDs being placed on two outer straight lines, while combinations of two red-light emitting LEDs and an yellow-light emitting LED being arranged between those two outer lines.
Fig.8 shows an arrangement of LEDs in the light source described in Registered Utility Model Gazette No.3132253. In a light source 81, white- light emitting LEDs 83a and 83b are placed in two outer lines, respectively, on a base board 82. Combinations of two red- light emitting LEDs 84, 84 and a yellow-light emitting LED 85 are arranged in another line between the two outer lines.
Such an LED light source having the color-light emitting LEDs in conjunction with the white-light emitting LEDs makes unnatural impression if one looks at it in just front thereof, where the color-light emitting LEDs are seen directly. Moreover, a reflected image of the light source is produced on a glossy surface of an illuminated object, so that the color-light emitting LEDs not only make intense visual impression, but also leave an after-image in complementary color in one's view after gazing at the reflected image.
LED light sources are widely applied in recent years to conventional illumination including those for home use, being formed not only in straight tube and circular shapes like fluorescent lights, but also in globe shape like incandescent lamps. In the latter case, usually a light source consists of a globe portion and a connecting element (power-inlet) of screw-in type like an incandescent lamp.
Fig. 9 and Fig.10 show a conventional globe-type LED lamp. A lamp 90 consists of a globe 91, an inlet 92, an LED circuit board 93, a power converter 94 for supplying electric power to the LED circuit board 93, and a wire 95. The globe 91 is shaped in conical cylinder. The inlet 92 is formed in a male screw compatible to female-screw sockets, serving as electric connection to supply electric power to the LED circuit board 93 from an external power source through the power converter 94. The LED circuit board 93 is attached at the top of the globe 91, while the inlet 92 is attached at the bottom thereof. The power converter 94 is formed in the inside of globe 91. A fin 91b for heat disposal out of the LED circuit board 93 is attached on the outer surface of globe 91.
As shown in Fig.10, the LED circuit board 93 is composed of a base board 93b and an LED light emitting device 93a fixed on one surface thereof, and a circuit component 94b being mounted on the other surface thereof. The power converter 94 is composed of the circuit component 94b mentioned above and a circuit component 94a which is mounted inside of the globe 91, these components being connected by the wire 95. The circuit component 94b on the LED circuit board 93 includes one or more integrated circuits composed of semi-conductor elements. Electric power supplied from the external power source through the inlet 92 is converted by the power converter 94 to be a required form for the light emitting device 93a, and then supplied thereto.
The LED illuminating apparatus as described above is compact and adapted to conventional screw-in type sockets, thus convenient in setting up and replacement, and therefore used more widely in recent years. Examples of LED illuminating apparatus of such kind are disclosed in Japanese Patent Applications Laid-open Nos. 2009-123641 , 2009-135026 , 2009-163955 , 2009-170114 , and 2009-176925 .
The LED illuminating apparatus, in spite of great advantage in less power consumption compared with the incandescent lamps, cannot refrain from elevation of temperature due to heat from the LED elements. Therefore, a means, such as a fin, is provided on the outer surface thereof in order to prevent temperature elevation.
Heat evolved from the LED elements in a conventional LED illuminating apparatus of globe type, however, cannot be removed sufficiently, even if it is provided with fins outside thereof. Thereby, the temperature of the apparatus, particularly, that of the power converter stored in the globe portion, is elevated after continued operation of the apparatus for a long time. Such elevated temperature makes the life of the apparatus be shortened due to its effect on the power converter, particularly on the circuit component attached to the LED circuit board.
Moreover, in the conventional LED illuminating apparatus of globe type, the LED circuit board, i.e. the light-emission portion, supported within the globe and the power inlet, i.e. the power- receiving portion, are integrated in a body.
Thus, the direction of the emitted light from the apparatus cannot be changed after the apparatus is once fixed to a power outlet tool such as a screw-in socket. In order to change the direction of the emitted light, the direction of the power outlet tool, such as a socket, has to be changed. Thus, an outlet tool having a structure capable of such changing is of necessity if the directional adjustment of illumination is required.
Further, the shell (globe) for the light-emission portion and the power control portion is usually composed of metal which is superior in heat conduction. Therefore, the illuminating apparatus is heavy in weight, resulting in greater burden of work for mounting or replacing the apparatus at higher elevation, particularly, in a case of handling them in large number at once. In addition, after using the apparatus for a long time, the globe composed of metal may cause burnt skin by elevated temperature thereof when it is touched by a hand for renewal or removal of the apparatus.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide an LED illuminating apparatus observed as a white-light source free from strangeness due to light in color which is emitted by a color-LED used in addition to a white-light emitting LED therein, and directly seen in front of the apparatus.
Another object of the present invention is to provide an LED illuminating apparatus free from harmful effects of a reflected image of color-LED on a glossy surface of an illuminated object, even if the color-LED is used in addition to a white-light emitting LED in the apparatus.
Still another object of the present invention is to provide an LED illuminating apparatus which provides not only sufficient intensity of illumination but also long life, being compact in addition.
Further object of the present invention is to provide an LED illuminating apparatus capable of changing the direction of the emitted light as required, even if it is inserted in a power outlet tool such as a socket which is kept fixed.
The present invention provides an LED illuminating apparatus including an LED light-emitting device and a base board having the light-emitting device mounted on one surface thereof. The light-emitting device includes a main LED light-emitting element, an additional LED light-emitting element, and an optical regulator which covers the additional LED light-emitting element. The main LED light-emitting element emits white light. The additional LED light-emitting element emits light different from the white light emitted by the main LED light-emitting element. The optical regulator is capable of scattering the light emitted by the additional LED light-emitting element in the vicinity of the surface of the base board to an extent that the periphery of the additional LED light-emitting element cannot be recognized easily from the front of the LED illuminating apparatus.
The light emitted by the additional LED light-emitting element may be light in color or white light of color temperature different from that emitted by the main LED light-emitting element. Light in color such as yellow, red, and so on is preferable.
A preferable optical regulator according to the present invention is a complex prism composed of a right-angle prism, a flat-convex lens, and a transparent column. These elements are so arranged that one end surface of the transparent column is in close contact with one surface of the right-angle prism neighboring the right angle thereof, the other end surface of the transparent column is in close contact with a flat surface of the flat-convex lens, and the other surface of the right-angle prism neighboring the right angle thereof faces the additional LED light-emitting element.
The flat-convex lens in the complex prism is preferably provided with a convex surface having radius of the curvature not less than the thickness of the lens but not beyond twice the thickness of the lens. The radius of the curvature equal to or slightly larger than the thickness of the lens is particularly suited.
The optical regulator is made of a transparent solid material such as glass, quartz, and various plastic resin including poly-acrylates, poly-methacrylates, polystylene, and poly-carbonates. Components may be integrated with each other. Particularly, the transparent column and the flat-convex lens may be integrated in a body in order to simplify manufacture thereof.
Light emitted by the additional LED light-emitting element and made incident to the complex prism is released mainly from the convex surface of the flat-convex lens as scattered light in broad angle. Part of the scattered light is reflected by the surface of the base board on which the LED light-emitting elements are placed, particularly in the neighborhood of main LED light-emitting element, and released in front of the LED board. The other part of the scattered light is released from the convex surface directly. Light released from a side surface of the transparent column also takes some part in the light scattered and released in front of the LED board.
Such light in color scattered from the complex prism is added to and mixed with white light emitted by main LED light-emitting element so that the white light released out of the LED illuminating apparatus is improved in color performance.
The main LED light-emitting element may be positioned along a circle around a point or inside of the circle, while the additional LED light-emitting element may be positioned along the same circle or out of the circle. The additional LED light-emitting element may be positioned along another circle of greater radius. In such an arrangement, the convex surface of the lens in the complex prism covering the additional LED light-emitting element is directed preferably toward the center of the circle.
Alternatively, the additional LED light-emitting elements may be positioned along a circle or inside of the circle, while the main LED light-emitting elements may be positioned out of the circle. The main LED light-emitting elements may be positioned along another circle of greater radius. In such an arrangement, the convex surface of the lens in the complex prism covering the additional LED light-emitting elements is directed preferably opposite to the center of the circle.
Two or more of the main LED light-emitting elements and of the additional LED light-emitting elements, respectively, may be used. The main LED light-emitting elements may be those emitting white light of similar color temperature but may be those emitting white light varied in color temperatures.
The main LED light-emitting element may be placed along one or more radiuses of a circle while the additional LED light-emitting element may be placed along other radiuses than those. If these radiuses are alternating each other, intensity and color performance of the emitted light are rendered more uniform, so is emission of the heat from the light source, too. The main and additional LED light-emitting elements may be placed along a common radius. The main LED light-emitting element may be placed at the center of the circle.
Preferably, three or more main LED light-emitting elements and three or more additional LED light-emitting elements are used so as to obtain sufficient intensity of light. In most cases, the main LED light-emitting elements having greater output of light compared with that of the additional LED light-emitting elements are used, because the main LED light-emitting elements take more part in the light beam from the light source, while LED light-emitting elements of smaller output than that of the main LED light-emitting elements may be used for the additional LED light-emitting elements, because improvement of the color performance is major purpose to use them. Optionally, a single LED light-emitting element may be used for the main LED light-emitting element if sufficient intensity of light can be obtained thereby.
The additional LED light-emitting elements may be those emitting light rich in longer wave-length components than the white light emitted by the main LED light-emitting elements. For example, a light source particularly suited for illuminating meats in a show case can be provided if the additional LED light-emitting elements are those emitting red light, because a light source of lower color temperature can be attained thereby compared with a light source composed of white-light emitting elements alone. Additional LED light-emitting elements emitting yellow light may be used to attain similar effect.
Alternatively, the additional LED light-emitting elements may be those emitting light rich in shorter wave-length components than the white light emitted by the main LED light-emitting elements. A light source particularly suited for illuminating green vegetables or jewels can be provided if the additional LED light-emitting elements are those emitting blue or green light, because a light source of higher color temperature can be attained thereby compared with a light source composed of white -light emitting elements alone.
A part of the additional LED light-emitting elements may emit light in different color from that emitted by others, for example, red vs. yellow or blue vs. green. The additional LED light-emitting elements emitting light rich in longer and shorter wave length components, respectively, may be used in combination. For example, some emit yellow light while others emit green light.
Preferably, the LED illuminating apparatus according to the present invention includes a light source portion composed of a base board having an LED light-emitting device on one surface thereof, and a power control portion for supplying electric power to the LED light-emitting device, a power receiving portion for supplying electric power from an external power source to the power control portion. The apparatus further includes a connecting portion for connecting the light source portion with the power control portion. The power control portion is formed integrally with the power receiving portion. The power control portion is separated from the light source portion across the connecting portion and space open to the outside surrounding the connecting portion. Preferably, the connecting portion is flexible and self form-keeping. The light source portion is preferably composed of the main LED light-emitting element and the additional LED light-emitting element in combination such as mentioned above.
The light source portion may be shaped in column, pole, or disc, and have the LED light-emitting device placed at the top. The base board for the LED light-emitting device may be mounted on the upper part of the light source portion.
Either of the power control portion and the light source portion may be provided with a shell formed of plastic or post-hardening synthetic resin.
Such synthetic resin may be selected from poly-ethylene resins, poly-propylene resins, poly-stylene resins, polycarbonate resins, poly-ester resins, acryl resins, epoxy resins, and urea resins (including co-polymers thereof).
The presence of the connecting portion between the power control portion and the light source portion is effective particularly for protecting the power control portion equipped with a semi-conductor integrated circuit from harmful elevation of the temperature thereof.
The light source portion may be provided with an opening for ventilating which is penetrated into the inside thereof on the side or at the bottom part, or both of them. Preferably, the bottom of the portion is provided with such an opening, especially in a case where the side and bottom parts of the light source portion are composed of synthetic resin.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a plan view of an LED lamp in preferred embodiments of the present invention;
Figure 2 is a partial cross-sectional view of the LED lamp shown in Fig. 1;
Figure 3 is a front view of an LED lamp of a first preferred embodiment of the present invention, particularly showing the major part of a light source portion thereof;
Figure 4 is a partial cross-sectional view along the line IV-IV in Fig. 3;
Figure 5 is a side view of a complex prism shown in Fig. 4;
Figure 6 is a front view of an LED lamp of a second preferred embodiment of the present invention, particularly showing the major part of a light source portion thereof;
Figure 7 is a front view of a conventional LED illuminating apparatus;
Figure 8 is a front view of another conventional LED illuminating apparatus;
Figure 9 is a plan view of a conventional LED lamp of globe type;
Figure 10 is a partial cross-sectional view of Fig. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in Fig. 1 and Fig. 2, an LED lamp 10 consists of a light source portion 1, an inlet 2 as a power receiving portion, a power control portion 4, and a connecting pipe 5 for connecting the light source portion 1 and the power control portion 4. The light source portion 1 is provided with an LED board 3 (refer to Fig.3) and a shell 1a. The connecting pipe 5 is a flexible metal pipe.
The LED board 3 is composed of a base board 3b and an LED light-emitting device 3a mounted on one surface thereof. The LED board 3 is connected with the power control portion 4 by a wire 3c. The shell 1a, shaped in a round disc, is provided surrounding and behind the LED board 3. An opening 1d is provided at a bottom 1c of the shell 1a. Fins 1b are provided on an outer surface of the light source portion 1 in order to prevent temperature elevation. The inlet 2 is composed of a male screw 2a, a top portion 2b, and an insulator 2c interposed between them. The male screw 2a and the top portion 2b are made of metal.
The major part of the light source portion 1 of the LED lamp 10 is shown in Fig.3, in which an optical regulator is omitted to avoid complexity of the drawing. The LED board 3 consists of three LED light-emitting elements 3A, nine LED light-emitting elements 3B, nine LED light-emitting elements 3C, and the base board 3b on which the LED light-emitting elements 3A, 3B, and 3C are disposed. The LED light-emitting elements 3A are placed along a circle R1 of the smallest diameter. The LED light-emitting elements 3C are placed along a circle R3 of the greatest diameter having the center common with the circle R1. Each of the LED light-emitting elements 3C is covered with the not-shown optical regulator. The LED light-emitting elements 3B are placed along a circle R2 of an intermediate diameter, which is slightly smaller than R3, at the positions crossing radiuses 40 degrees remote from each other. At the positions crossing the radiuses dividing the angle of 40 degrees mentioned above to two halves are placed the LED light-emitting elements 3C. The LED light-emitting elements 3A are disposed at the positions crossing the radiuses common to the corresponding LED light-emitting elements 3C.
The LED light-emitting elements 3A emit white light of higher temperature (6500K, for example). The LED light-emitting elements 3B with the greatest output emit white light of rather lower color temperature (3400K, for example). The LED light-emitting elements 3C, the smallest in output, emit light in color, yellow light for example. The LED light-emitting elements 3A and 3B are "main LED light-emitting elements" according to the present invention, whereas the LED light-emitting elements 3C are "additional LED light-emitting elements" according to the present invention.
As shown in Fig.4, in front of each of the LED light-emitting elements 3C, an optical regulator formed of a complex prism 11 (omitted in Fig.3) is disposed. The complex prism 11 consists of a right-angle prism 21, a transparent column 22, and a flat-convex lens 23. The right-angle prism 21 has a surface 21a and a surface 21b together with a slope 21c slanted 45 degrees to the surfaces 21a and 21b. The transparent column 22 has end surfaces 22d and 22e. The flat-convex lens 23 has a flat surface 23f and a convex surface 23g. The transparent column 22 and the flat-convex lens 23 are integrated in a single body at the surface 22e and the surface 23f, either being imaginary plane simply for explanation. The surface 21a of the right-angle prism 21 faces with the LED light-emitting element 3C. Fig.5 is a side view of the complex prism 11 from the side of the flat-convex lens 23. The complex prism 11 is directed so that the convex surface 23g is confronted with the center of the circles R1, R2 and R3.
Color light emitted by the LED light-emitting element 3C passes through the complex prism 11, and is released mainly from the convex surface 23g of the flat-convex lens 23 as scattered light in broad angle. Part of the scattered light is reflected by the surface of the base board 3b on which the LED light-emitting devices 3a are placed, particularly in the neighborhood of the LED light-emitting elements 3B, and released in front of the LED board 3. Other part of the scattered light is released directly from the convex surface 23g. Light released from a side surface of the transparent column 22 also takes some part in the light scattered and released in front of the LED board 3.
Such color light scattered from the complex prism 11 and the white light of higher color temperature from the LED light-emitting elements 3A are added to the white light of lower color temperature from the LED light-emitting elements 3B, so that the white light with improved color performance is released out of the light source portion 1 of the LED lamp 10.
Fig.6 shows the major part of the light source portion 1 (refer to Fig.1) in accordance with another preferred embodiment of the present invention. Description is omitted related to the parts similar to those of the first preferred embodiment, excluding the light source portion 1. An LED board 33 is composed of the base board 3b, five LED light-emitting elements 33A, and five LED light-emitting elements 33C, being mounted within an opening of the shell 1a. The LED light-emitting elements 33A are placed along a circle R11 of smaller diameter. The LED light-emitting elements 33C are placed along a circle R12 of greater diameter having the center common with the circle R11, and covered with the complex prism 11 (not shown in Fig.6). The LED light-emitting elements 33A are placed at the positions crossing radiuses 72 degrees remote from each other. The LED light-emitting elements 33C are placed at the positions crossing the radiuses dividing the angle of 72 degrees mentioned above to two halves. The complex prism 11 (not shown in Fig. 6) is directed so that the convex surface 23g is confronted with the center of the circles R11 and R12.
The LED light-emitting elements 33A emit white light of color temperature 6500K, for example. The LED light-emitting elements 33C emit yellow light, for example. The LED light-emitting elements 33A are "main LED light-emitting elements" according to the present invention, whereas the LED light-emitting elements 33C are "additional LED light-emitting elements" according to the present invention. The function of the LED board 33 in operation is analogous to that of the LED board 3 in the first preferred embodiment.
The LED light-emitting elements 3C in the LED board 3 and the LED light-emitting elements 33C in the LED board 33 may be those emitting red light or those emitting green light.
Various changes and modifications are possible in the present invention and may be understood to be within the present invention.

Claims

An LED illuminating apparatus (10) including an LED light-emitting device (3a) and a base board (3b) having said light-emitting device (3a) mounted on one surface thereof, wherein
said LED light-emitting device (3a) comprises a main LED light-emitting element (3A), an additional LED light-emitting element (3C), and an optical regulator which covers said additional LED light-emitting element (3C),
said main LED light-emitting element (3A) emits white light;
said additional LED light-emitting element (3C) emits light different from the white light emitted by said main LED light-emitting element (3A), and
said optical regulator is capable of scattering the light emitted by said additional LED light-emitting element (3C) in the vicinity of the surface of said base board (3b) to an extent that the periphery of said additional LED light-emitting element (3C) cannot be recognized easily from the front of said LED illuminating apparatus (10).
An LED illuminating apparatus (10) of Claim 1, wherein said additional LED light-emitting element (3C) emits light in color.
An LED illuminating apparatus (10) of Claim 1 or 2, wherein said additional LED light-emitting element (3C) emits white light of color temperature different from that of the white light emitted by said main LED light-emitting element (3A).
An LED illuminating apparatus (10) of Claim 1, 2 or 3, wherein said optical regulator comprises a complex prism (11) composed of a right-angle prism (21), a flat-convex lens (23), and a transparent column (22), which are arranged such that one end surface (22d) of said transparent column (22) is in close contact with one surface (21b) of said right-angle prism (21) neighboring the right angle thereof, the other end surface (22e) of said transparent column (22) is in close contact with a flat surface (23f) of said flat-convex lens (23), the other surface (21a) of said right-angle prism (21) neighboring the right angle thereof faces said additional LED light-emitting element (3C), and a convex surface (23g) of said flat-convex lens (23) faces open space.
An LED illuminating apparatus (10) of Claim 4,
wherein
said main LED light-emitting element (3A) is positioned along or within a circle (R1), said additional LED light-emitting element (3C) being positioned outside said circle (R1), and
said complex prism (11) is so arranged that said convex surface (23g) of said flat-convex lens (23) facing open space is directed to the center of said circle (R1).
An LED illuminating apparatus (10) including a light source portion (1) comprising an LED board (3) composed of a base board (3b) having an LED light-emitting device (3a) on one surface thereof, a power control portion (4) for supplying electric power to said LED light-emitting device (3a), and a power receiving portion (2) for supplying electric power from an external power source to said power control portion (4), wherein
said power control portion (4) is formed integrally with said power receiving portion (2),
a connecting portion (5) for connecting said light source portion (1) with said power control portion (4) is disposed in said LED illuminating apparatus (10), and
said power control portion (4) is separated from said light source portion (1) across said connecting portion (5) and space open to the outside surrounding said connecting portion (5).
An LED illuminating apparatus (10) of Claim 6, wherein said connecting portion (5) is flexible and self form-keeping.
An LED illuminating apparatus (10) of Claim 6 or 7,
wherein
said LED light-emitting device (3a) comprises a main LED light-emitting element (3A), an additional LED light-emitting element (3C), and an optical regulator which covers said additional LED light-emitting element (3C),
said main LED light-emitting element (3A) emits white light,
said additional LED light-emitting element (3C) emits light different from the white light emitted by said main LED light-emitting element (3A), and
said optical regulator includes a complex prism (11) composed of a right-angle prism (21), a flat-convex lens (23), and a transparent column (22), which are arranged such that one end surface (22d) of said transparent column (22) is in close contact with one surface (21b) of said right-angle prism (21) neighboring the right angle thereof, the other end surface (22e) of said transparent column (22) is in close contact with a flat surface (23f) of said flat-convex lens (23), the other surface (21a) of said right-angle prism (21) neighboring the right angle thereof faces said additional LED light-emitting element (3C), and a convex surface (23g) of said flat-convex lens (23) faces open space.
An LED illuminating apparatus (10) comprising an LED light-emitting device (3a) and a base board (3b) having said light-emitting device (3a) mounted on one surface thereof, wherein
said LED light-emitting device (3a) comprises an LED light-emitting element (3C),
said LED light-emitting device (3a) further comprises an optical regulator which covers said LED light-emitting element (3C), and
said optical regulator comprises a complex prism (11) which is composed of a right-angle prism (21), a flat-convex lens (23), and a transparent column (22), which are arranged such that one end surface (22d) of said transparent column (22) is in close contact with one surface (21b) of said right-angle prism (21) neighboring the right angle thereof, the other end surface (22e) of said transparent column (22) is in close contact with a flat surface (23f) of said flat-convex lens (23), the other surface (21a) of said right-angle prism (21) neighboring the right angle thereof faces said LED light-emitting element (3C), and a convex surface (23g) of said flat-convex lens (23) faces open space.