CN102654252B - Lens and illumination device - Google Patents

Abstract

The present invention provides a lens which can easily mount LEDs, prevent uneven brightness of emitted light, and uniformly emit light in a substantially spherical shape, and an illuminating device using the lens. The lighting device has a substrate, a luminous body provided on the upper side of the substrate, and a lens covering the upper side of the luminous body, wherein the lens has a surface opposite to the light-emitting surface of the luminous body, and The surface opposite to the surface opposite to the light-emitting surface of the luminous body is concave to the inside of the lens, and the concave surface to the inside of the lens has the function of emitting light from the curved surface incident in the lens to the top of the lens, and to the lens. The side and bottom reflection function of the illuminant is provided with a concave portion on a part of the surface opposite to the light emitting surface of the luminous body. The concave portion uses the concave surface to reflect the light incident from the concave portion into the lens to the side and bottom of the lens. Shoot multiple shapes from above.

Description

Lenses and Lighting Devices

technical field

The present invention relates to a lighting device, and more particularly to a lighting device that includes a semiconductor light emitting element such as an LED (light emitting diode) as a light source and is mainly used as a substitute for an incandescent lamp.

Background technique

In recent years, in order to prevent global warming and promote energy saving, in the field of lighting, research and development of lamps using LEDs have been carried out as substitutes for conventional incandescent lamps. This is because lamps using LEDs are energy efficient compared to existing incandescent lamps. In consideration of expansion of applications of lamps using LEDs, existing incandescent lamp sockets are required to be used as they are, and it is desired to use them on a par with existing incandescent lamps. In addition, since an incandescent lamp uniformly emits light in a substantially spherical shape from the front to the rear of the incandescent lamp, lamps using LEDs are required to direct irradiation of light equivalent to the case where the incandescent lamp is mounted in a lighting fixture. However, since LEDs have strong rectilinear propagation properties of emitted light, when they are used on the same level as conventional incandescent lamps, it is necessary to expand the irradiation range (light distribution) of light without uneven brightness.

As an example of means for expanding the light distribution of light, as described in Patent Document 1, there is a method in which LEDs are arranged on the outer surface of a substantially cylindrical base, and light transmission is provided in a manner covering the base and the LEDs. of the hood, thereby extending the light distribution. However, since it is necessary to make the base substantially cylindrical and/or arrange LEDs and the like on the substantially cylindrical base, the manufacturing process may become complicated.

There is also a method of using a lens as a method of expanding light distribution. As prior art for expanding light distribution using a lens, there are technologies disclosed in Patent Document 2 and Patent Document 3. In Patent Document 2, it is disclosed that a light flux control member (lens) is provided on the upper part of the light emitting element, and that unevenness in brightness is prevented by providing a concave portion and a vent groove on the surface of the light flux control member opposite to the light emitting element. The shape of the lens through which light emerges. In addition, Patent Document 3 discloses that a first refraction surface having a bottom surface, a reflection surface, and a first refraction surface inclined at an angle with respect to the central axis of the lens, and a second refraction surface extending from the bottom surface to the first refraction surface as a smooth curved surface are disclosed. The lens is set on the upper part of the light-emitting element so that the light is emitted to the side of the lens shape.

Patent Document 1: JP-A-2008-103112

Patent Document 2: JP-A-2009-211990

Patent Document 3: JP-A-2004-133391

However, the lens disclosed in Patent Document 2 spreads the light irradiated from the light-emitting element uniformly in the irradiation direction (front) and can prevent the occurrence of brightness unevenness. outgoing light. Therefore, the illuminating device using the lens disclosed in Patent Document 2 cannot be used as a substitute for an incandescent lamp capable of emitting light to the side and rear. In addition, although the lens disclosed in Patent Document 3 can emit light in the side direction, it hardly emits light forward and backward, so it cannot be used as a substitute for an incandescent lamp. In addition, FIG. 10 shows the state of light emission when patent document 2 and patent document 3 are simply combined. Since more light is emitted to the side and the amount of light emitted to the front and rear is less, it is difficult to obtain the effect of uniformly emitting light in a substantially spherical shape required by an incandescent lamp substitute.

Contents of the invention

It is an object of the present invention to provide a lens that allows easy mounting of LEDs, prevents uneven brightness of emitted light, and uniformly emits light in a substantially spherical shape, and an illuminating device using the lens.

The lighting device of the present invention has a substrate, a luminous body arranged on the upper surface side of the substrate, and a lens covering the luminous body, wherein the lens has a surface opposite to the luminous surface of the luminous body, and a surface opposite to the luminous body. The opposite side of the surface opposite to the light-emitting surface is concave to the inside of the lens, and the surface concave to the inside of the lens has the function of making the light incident into the lens from the surface opposite to the light-emitting surface of the illuminant emit to the upper side of the lens , and the function of reflection to the side and below of the lens, a recess is provided on a part of the surface opposite to the light-emitting surface of the illuminant, and the recess is the following shape, that is, the surface that is concave to the inside of the lens makes the incident from the recess A shape in which light entering the lens is reflected toward the side and bottom of the lens more than it is emitted toward the top of the lens.

Alternatively, the lighting device of the present invention has a substrate, a luminous body disposed on the upper side of the substrate, and a lens covering the luminous body, wherein the lens has a surface opposite to the light-emitting surface of the luminous body, and a surface opposite to the light-emitting surface. The opposite side of the surface opposite to the light-emitting surface of the body is concave to the inside of the lens, and the concave surface to the inside of the lens has an inclination from the bottom of the surface concave to the inside of the lens toward the top and bulges above the lens , On the surface opposite to the light-emitting surface of the illuminant, a concave portion concaved toward the inner side of the lens is provided.

Or, the lens of the present invention has a surface concave to the inside of the lens and a surface on the opposite side of the surface concave to the inside of the lens, and the surface concave to the inside of the lens has a concave surface from the inside of the lens. The bottom of the surface is inclined toward the top and swells upward of the lens, and a concave portion concave inward of the lens is provided on the opposite surface.

Alternatively, the lighting device of the present invention has a substrate, a plurality of semiconductor light emitting elements arranged above the substrate, and a lens arranged above the substrate in order to cover the semiconductor light emitting elements, wherein the lens includes an upper portion, a side portion and a bottom portion , the bottom has the first surface of the lens, the side has the second and third surfaces of the lens, the upper part has the fourth and fifth surfaces of the lens, and the first surface is a hemispherical curved surface concave inward of the lens , and set to cover the semiconductor light emitting element, one end of the second surface is connected to the end of the first surface, the second surface is a curved surface covering the side of the first surface, one end of the third surface is connected to the other end of the second surface, One end of the fourth surface is connected to the other end of the third surface, the fourth surface is a curved surface concave inward of the lens, and the fifth surface is connected to the other end of the fourth surface, which is a surface substantially parallel to the substrate, from The light of the semiconductor light-emitting element is incident into the lens from the first surface, and the light incident from the first surface is directed toward the second surface, the third surface, the fourth surface, and the fifth surface, and the second surface makes the light incident from the first surface Refracted toward the upper side of the lighting device and emitted from the lens, the third surface reflects the light incident from the first surface toward the fourth surface in the lens, and refracts the light reflected from the fourth surface toward the side and lower side of the lighting device And emitted from the lens, the fourth surface makes the light incident from the first surface reflect in the lens toward the third surface, refracts the light reflected from the third surface toward the top of the lighting device and emits from the lens, the fifth surface The light incident from the first surface is emitted from the lens toward the upper side of the lighting device, the first surface is provided with a concave portion recessed inwardly of the lens, and the light incident from the semiconductor light emitting element to the concave portion is directed to the fourth surface. More than towards the fifth side.

The effects of the invention are as follows.

According to the present invention, in an illuminating device having a substrate, a luminous body disposed on the upper surface side of the substrate, and a lens covering the luminous body, the lens has a surface opposite to the light-emitting surface of the luminous body, and an The opposite side of the opposing surface is concave toward the inside of the lens, and the concave surface toward the inside of the lens has the function of emitting light incident into the lens from the surface opposite to the light-emitting surface of the illuminant to the upper side of the lens, And the function of reflection to the side and bottom of the lens, a concave part is provided on a part of the surface opposite to the light-emitting surface of the illuminant, and the concave part is to use the surface concave to the inside of the lens to make the light incident into the lens from the concave part to the lens The side and bottom of the lens reflect more than the shape above the lens. Therefore, it is possible to realize a lighting device that can easily install LEDs, prevent uneven brightness, and emit light uniformly in a substantially spherical shape.

Or, according to the present invention, in a lighting device having a substrate, a luminous body disposed on the upper surface side of the substrate, and a lens covering the luminous body, the lens has a surface opposite to the light-emitting surface of the luminous body, and a surface opposite to the luminous body. The opposite side of the surface opposite to the light-emitting surface of the lens is a surface concave to the inside of the lens, and the surface concave to the inside of the lens has an inclination from the bottom of the surface concave to the inside of the lens toward the top and bulges toward the top of the lens, The surface facing the light emitting surface of the illuminant is provided with a concave portion recessed inwardly of the lens, so that the LED can be easily mounted, and can realize a lighting device that prevents brightness unevenness and uniformly emits light in a substantially spherical shape.

Or, according to the lens of the present invention, the lens has a surface concave to the inside of the lens and a surface on the opposite side of the surface concave to the inside of the lens, and the surface concave to the inside of the lens has a surface concave from the inside of the lens. The bottom of the concave surface is inclined toward the top and swells upward of the lens, and a concave portion is provided on the opposite surface to the inside of the lens, so that the installation of the LED is simple and uneven brightness can be prevented. A lens that emits light uniformly in a roughly spherical shape.

Alternatively, according to the present invention, in an illumination device having a substrate, a plurality of semiconductor light emitting elements disposed above the substrate, and a lens disposed above the substrate to cover the semiconductor light emitting elements, the lens includes an upper portion, a side portion and a bottom portion, The bottom has the first surface of the lens, the side has the second surface and the third surface of the lens, the upper part has the fourth surface and the fifth surface of the lens, and the first surface is a hemispherical curved surface concave to the inside of the lens, And set to cover the semiconductor light emitting element, one end of the second surface is connected to the end of the first surface, the second surface is a curved surface covering the side of the first surface, one end of the third surface is connected to the other end of the second surface, and the second surface is connected to the other end of the second surface. One end of the four sides is connected to the other end of the third surface, the fourth surface is a curved surface concave inward of the lens, and the fifth surface is connected to the other end of the fourth surface, which is a surface roughly parallel to the substrate, from semiconductor The light of the light-emitting element is incident into the lens from the first surface, and the light incident from the first surface is directed toward the second surface, the third surface, the fourth surface, and the fifth surface, and the second surface makes the light incident from the first surface toward the lens. The upper side of the lighting device is refracted and emitted from the lens, and the third surface reflects the light incident from the first surface toward the fourth surface in the lens, and the light reflected from the fourth surface is refracted toward the side and the bottom of the lighting device and then Out from the lens, the fourth surface reflects the light incident from the first surface toward the third surface in the lens, refracts the light reflected from the third surface toward the upper side of the lighting device, and emits it from the lens. The light incident from the first surface is emitted from the lens toward the upper side of the lighting device, and the first surface is provided with a concave portion recessed inwardly of the lens, and the light incident from the semiconductor light emitting element to the concave portion is directed toward the fourth surface. Since there are many faces toward the fifth surface, it is possible to realize an illuminating device in which LEDs are easily mounted, unevenness in brightness is prevented, and light is emitted uniformly in a substantially spherical shape.

Description of drawings

1( a ) is a cross-sectional view viewed from the side of the light emitting unit of Example 1 of the present invention, and (b) is an isometric view of the lens of Example 1 of the present invention.

Fig. 2 is a diagram showing the state of light rays in Example 1 of the present invention.

Among Fig. 3, figure (a) is the occasion of changing the installation of the lens of embodiment 1 of the present invention, the cross-sectional view viewed from the side of light-emitting part, figure (b) is the isometric projection view of the lens of Fig. 3 (a) .

Among Fig. 4, figure (a) is the occasion of changing the mounting of the lens of embodiment 1 of the present invention, the sectional view observed from the side of light-emitting part, figure (b) is the isometric projection view of the lens of Fig. 4 (a) .

Fig. 5 is a cross-sectional view seen from the side when Example 1 of the present invention is used as an incandescent lamp.

Fig. 6 is a cross-sectional view viewed from the side of a light emitting unit according to Example 2 of the present invention.

In FIG. 7 , (a) is a cross-sectional view viewed from the light emitting part of Example 3 of the present invention, and (b) is an isometric projection view of the lens in FIG. 7( a ).

Fig. 8 is a cross-sectional view seen from the side when Example 4 of the present invention is used as an incandescent lamp.

Fig. 9 is a cross-sectional view seen from the side when Example 5 of the present invention is used as an incandescent lamp.

Fig. 10 is a cross-sectional view of a conventional lens.

In the picture:

1-lens, 2-LED module, 3-light-emitting surface (fluorescent face), 4-substrate, 5-optical axis, 6-grip head, 7-extending part, 10, 151-frame, 11-circuit, 12-lamp holder, 13, 50-cover, 20-lens pressure plate, 21-screw, 100-lens including installation part, 150-other forms of substrate, 200-other forms of lens including installation part, 300, 400, 500 -Other forms of lens, 501-ray of light, 600-lens of conventional example, a-flat part, b-concave surface of funnel shape, c-refractive surface, d-curved surface of bowl shape, e-curved surface, f-conical The concave part, g-Mount Fuji-shaped concave surface, h-multiple conical concave parts.

Detailed ways

In the lighting device according to the present invention, it is characterized in that at least one luminous body is provided on one substrate, a light-transmitting cover is provided to protect the luminous body, and a lens is provided above the light-emitting surface of the luminous body and inside the cover. Among the lenses, there is a lens having a substantially conical concave portion at the approximate center of the surface opposite to the light emitting surface, and the size of the bottom surface of the concave portion is smaller than the area of the light emitting surface.

As another example, it is characterized in that the surface opposite to the light emitting surface is a curved surface, and a funnel-shaped recess is provided on the opposite side of the surface. In addition, as another example, a lens having a flat portion is provided on the bottom surface of the funnel-shaped concave portion. The above-mentioned lens has a substantially conical concave portion having a bottom surface smaller than the light emitting surface on a surface opposite to the light emitting surface, thereby suppressing unevenness in brightness of light emitted toward the cover surface. In addition, the funnel-shaped concave portion formed on the opposite side of the light emitting surface increases the light emitted backward. In addition, by making the bottom surface of the funnel-shaped concave portion flat, the amount of light emitted forward can be increased. By combining these effects, it is possible to obtain a lens that emits light uniformly on the surface of the cover. In addition, by giving the cover a scattering property, the uniformity of light can also be increased. In addition, in the lighting device according to the present invention, it is desirable to have a shape similar to that of a light bulb in consideration of use as an alternative to an incandescent lamp. As an example of implementation, an LED module is used as a luminous body, a frame body having a cavity is provided on the back side of a substrate on which the LED module is mounted, and a cap for connecting to a socket of a conventional incandescent lamp is provided. In addition, a circuit for driving the LED module is housed in the cavity of the housing.

Next, Embodiments 1 to 5 will be described using the drawings. As a basic configuration, an LED module 2 as a luminous body is provided on one surface of a base body 4 . Next, in Examples 1 to 5, the direction of one surface on which the LED module 2 is provided is referred to as the front (upper direction) and the direction of the other surface is referred to as the rear (lower side) with reference to the substrate 4 . The directions other than the front and the bottom are taken as sides. When the globe side and the base side are used in the light bulb, the globe side is upward, and the base side is downward.

Example 1

In this embodiment, an example of a lens that prevents brightness unevenness and expands light distribution will be described.

Fig. 1(a) is a cross-sectional view viewed from the side of a light emitting unit according to Example 1 of the present invention. The LED module 2 is mounted on one surface of the substrate 4 , and the light emitting surface 3 of the LED module 2 faces forward (upper) which is a direction opposite to the substrate 4 . In addition, the lens 1 is provided so that most of the lens 1 is located in front of (upper) the light emitting surface 3 of the LED module 2 . The substrate 4 is a component for mounting the LED module 2 . Electric power is supplied from the circuit to the LED module 2 , and light is irradiated from the light emitting surface 3 to the front (upper side) of the LED module 2 . The light irradiated from the light emitting surface 3 enters the lens 1 .

The lens 1 is arranged to cover the LED module 2 . In this embodiment, the lens 1 includes a flat portion a (fifth surface), a concave surface b (fourth surface), a refractive surface c (third surface), a curved surface d (second surface), and a curved surface e (first surface) , concave f and grab head (take つ hanging かり) part 6. In the lens 1 , the curved surface e is a surface facing the LED module 2 . The LED module 2 is surrounded by the curved surface e and the substrate 4 . The curved surface e has a hemispherical shape covering the LED module 2 arranged on one surface of the flat substrate 4 . A conical recess f is formed on the curved surface e. Assuming that a typical ray of light irradiated from the light emitting surface 3 of the LED module 2 is the optical axis 5 , a concave portion f is formed at a portion where the optical axis 5 intersects the curved surface e. In the curved surface e, the part farthest from the substrate 4 is defined as the curved surface e1. In this embodiment, since the optical axis 5 passes through the curved surface e1, the concave portion f is provided on the curved surface e1. The concave portion f is provided to be concave toward the inner side of the lens 1 . The recess f is a conical recess. Light from the light emitting surface 3 of the LED module 2 goes toward the curved surface e and the concave portion f, and enters the lens 1 from the curved surface e and the concave portion f. The light emitting surface of the lens 1 includes a flat portion a, a concave surface b, a refracting surface c, and a curved surface d. The flat part a and the concave surface b are located on the upper part of the lens 1 , and the refracting surface c and the curved surface d are located on the side part of the lens 1 . The concave surface b has an inclination such that it bulges upward from the lens toward a portion connecting the concave surface b and the refractive surface c from the flat portion a. A substantially funnel shape is formed by the flat portion a, the concave surface b, and the refracting surface c. The refractive surface c is located in the range from the side surface to the rear of the concave surface b. A flat portion a is provided on the bottom surface surrounded by the concave surface b. The concave surface b has a function as a surface that reflects light incident on the lens 1 from the curved surface e and the concave portion f in the direction of the refracting surface c located on the side and rear of the lens 1, and transmits the light reflected by the refracting surface c to the lens. 1 function of front injection. The flat portion a has a function of transmitting light entering the lens 1 from the curved surface e and the concave portion f to the front of the lighting device. The flat portion a is used to increase the output amount of light toward the front of the lighting device. In addition, the refractive surface c has the function of refracting the light reflected by the concave surface b and emitting it from the lens 1 to the side and rear of the lighting device, and the function of reflecting the light incident from the curved surface e in the direction of the concave surface b. The curved surface d has a function of refracting light entering the lens 1 from the curved surface e and emitting it from the lens 1 . The light from the curved surface d is emitted within a range from the front to the side of the lighting device. By forming the conical concave portion f on the curved surface e, the amount of light incident on the concave surface b can be increased. By increasing the amount of light incident on the concave surface b, the amount of light reflected from the concave surface b can be increased, so that light can be irradiated to the front, side, and rear of the bulb, and uneven brightness can be prevented. The light incident from the concave portion f is reflected by the concave surface b, and the emission of light from the side of the lighting device to the rear is increased compared with the case where only the curved surface e is provided. By increasing the emission of light from the side to the rear of the lighting device, it has the function of reducing the brightness unevenness of the lighting device as a whole.

The angle θ1 formed by the optical axis 5 and the conical concave portion f is desirably about 10° to 50° in consideration of the incident light on the concave surface b. For example, when the angle θ1 is 48°, it is desirable that the length of the flat portion a be 0.6 mm, and the size of the concave surface b be an arc of 1/4 of an ellipse with a radius of 6 mm×12 mm. However, if the angle of θ1 and the size of the flat portion a change, the size of the concave surface b also changes. In addition, when the opening of the concave portion f on the curved surface e is referred to as the bottom surface of the conical concave portion f, it is desirable that the size _X1 of the bottom surface of the concave portion f is smaller than the size _X2 of the light emitting surface 3 . Since X ₁ < X ₂ , two types of light reflected by the concave surface b through the concave portion f and two kinds of light reflected by the concave surface b through the curved surface e can be generated, thereby preventing unevenness in brightness from spreading the outgoing light from the side to the rear. The size ratio of X ₁ and X ₂ is preferably around 1:2 in consideration of the light incident on the concave surface b. For example, when _X1 is 3.4mm, the size of _X2 is preferably about 8mm. In addition, when the angle of θ1 is 48°, it is preferable as follows: the length of the flat portion a is 0.6 mm, the size of the concave portion b is an arc of 1/4 of an ellipse with a radius of 6×12 mm, and the concave portion b and the refractive surface c The angle formed is 55°, the vertical base of the curved surface d and the curved surface e is 1mm, the curved surface d is an arc of a part of an ellipse with a radius of 9mm×12mm, and the curved surface e is an arc of a part of an ellipse with a radius of 3mm×8mm, the lens 1 The thickness of the central part is 0.5 mm. However, other ratios may be used as long as the curvature of the concave surface b is adjusted to adjust the output amount of light to the rear.

The outer shape of the lens 1 is a combination of a substantially funnel-shaped and a substantially bowl-shaped (bowl-shaped) such that their respective small-area parts face each other. When the lens 1 is viewed from the side, it has a substantially hourglass shape. The substantially funnel-shaped outer peripheral side is the refraction surface c referred to in this embodiment, and the substantially funnel-shaped inner peripheral side is the concave surface b referred to in this embodiment. The portion surrounded by the substantially funnel-shaped inner peripheral side is the bottom surface a in this embodiment. The generally bowl-shaped outer peripheral side is the curved surface d in this embodiment, and the inner peripheral side of the substantially bowl-shaped truncated cone is the curved surface e mentioned in this embodiment. A concave portion is provided on a part of the curved surface e. The concave portion provided in a part of the curved surface e is the concave portion f referred to in this embodiment. In this embodiment, the shape of the recess f is conical. One end of the curved surface d is connected to the end of the curved surface e, and one end of the refraction surface c is connected to the other end of the curved surface d. One end of the concave surface b is connected to the other end of the refractive surface c, and the bottom surface a is connected to the other end of the concave surface b. In the present embodiment, a general funnel shape and a bowl shape are shown, but it is not limited thereto. The outer shape of the lens 1 is not limited as long as the function of each surface is realized.

The lens 1 is arranged to cover the LED module 2 by the curved surface e. Light from the light emitting surface 3 of the LED module 2 enters the curved surface e and the concave portion f. The light incident on the curved surface e is refracted according to the curvature of the curved surface e and the refractive index of the lens 1 . The light from the LED module 2 with strong rectilinear propagation is extended to the forward light distribution by the curved surface e. In addition, the light incident on the concave portion f is also refracted. The light passing through the curved surface e reaches the flat surface a, the curved surface b, the refracting surface c and the curved surface d. The light passing through the concave portion f reaches the curved surface b. The light that has reached the flat surface a is emitted forward. Part of the light that has reached the curved surface b is emitted forward from the curved surface b, and the rest of the light is reflected into the lens 1 again. The light that reaches the refracting surface c and the curved surface d from the curved surface e and the concave surface b is refracted and emitted to the front, side and rear. The curved surface e is provided to expand the light distribution of the light from the LED module 2 . The recess b is provided to transmit light forward or reflect it inside the lens 1 . The flat surface a is provided to transmit light forward of the lens 1 . The refractive surface c is provided to direct light toward the side and rear of the lens 1 . The curved surface d is set to direct the light towards the front and side.

The lens 1 can be manufactured using a number of known techniques such as lathes, injection moulding, light modeling and casting. The lens 1 is made of polymethyl methacrylate (PMMA, commonly known as propylene) or polycarbonate (PC, commonly known as Polyka). However, it is not limited to these materials as long as it is a light-transmitting material, but from the viewpoint of energy saving, it is preferable to use a material with a small loss of light in the lens. In addition, various materials may be used, or the lens 1 may have scattering characteristics by mixing fine particles of about 1000 nm in size made of polymethyl methacrylate and/or polycarbonate, etc. inside the lens 1 . By giving the lens 1 a scattering characteristic, although the loss of light due to scattering increases, it is possible to have more uniform light with less unevenness in brightness.

The refractive index of the lens 1 is desirably about 1.54 which a common transparent member has, but it may have a higher or lower refractive index depending on the material used. The angle of refraction and/or reflection of light inside the lens 1 depends on the refractive index, so a change in shape is required depending on the refractive index of the material used for the lens 1 .

FIG. 1( b ) shows an isometric view of the lens 1 . As an example of the means for mounting the lens 1 on the substrate 4, at least two holes are opened on the substrate 4, and a grip 6 is formed on a cylindrical portion extending from the bottom surface of the lens 1 to prevent the lens from falling off. installation method. In order to prevent the deviation of the lens 1 in the up and down direction, it is preferable to form a gripping portion 6 on both sides of the upper side and the lower side with respect to the substrate 4 of the part of the cylindrical part that is in contact with the substrate 4 (in FIG. 1 (a) , only the lower gripping head 6) is shown. In addition, the lens 1 may be mounted on the substrate 4 by adjusting the thickness of the columnar portion of the lens and the fitting of the hole of the substrate without forming the gripping portion 6 .

Fig. 2 is a diagram showing the state of light rays in Example 1 of the present invention. The light emitted from the light emitting surface 3 of the LED module 2 enters the lens 1 from the curved surface e and the concave portion f, and exits the lens 1 from the flat portion a, the concave surface b, the refracting surface c, and the curved surface d.

As another example of the mounting method, FIG. 3 shows a method of mounting the lens 100 on the substrate 4 . The basic configurations of the lens 1 and the lens 100 are the same. There is a member 106 extending flatly from the bottom surface of the lens 100 along the upper surface of the substrate 4 , and both ends of the member 106 are fitted into the end surfaces of the substrate 4 to be fixed. In order to fix the lens 100, although an adhesive such as silicon can be used, it is also possible to form the gripper 6 to prevent it from coming off, as in the above-mentioned attachment example. According to the method shown in this embodiment, compared with the case of FIG. 1 in which holes are opened in the substrate 4 near the LED module 2, since the area of the substrate 4 near the LED module 2 as a heat generating body becomes larger, it has the advantage of being easy to use. The heat from the LED module 2 is dissipated through the substrate 4 .

In addition, FIG. 4 shows a method of mounting the lens 200 on the substrate 4 as another example of the mounting method. The basic configurations of the lens 1 and the lens 200 are the same. At least two protruding parts 7 are formed at the bottom of the lens 1, the protruding parts 7 are pressed on the substrate 4 with a pressure plate 20, and the substrate 4 and the pressure plate 20 are fastened and connected with screws 21, so that the lens 200 is installed on the substrate 4 on. In this embodiment, screws 21 are used to mount the substrate 4 and the lens 200, and since no resin such as silicon is used for bonding, it has the effect of preventing the adhesive from deteriorating with time due to heat or the like.

As the material of the substrate 4 , it is desirable to use a member with high thermal conductivity in consideration of heat dissipation. For example, it is preferable to use metal materials such as aluminum or aluminum alloy, copper, etc., but other materials may be used if it is a part with high thermal conductivity.

Fig. 5 is a cross-sectional view showing a case where the lens of the present invention is used as an illuminating device as an alternative to an incandescent lamp. The basic structure is as follows: the LED module 2 is mounted on the substrate 4, the lens 1 is provided on the upper part of the LED module 2, and the light-transmitting cover 13 is provided to cover the substrate 4. The housing 10 having a cavity is equipped with an electric circuit 11 inside the housing 10 and has a base 12 for connecting to a socket of an existing incandescent lamp. Instead of merely simulating the shape of an incandescent lamp, the lens 1 expands the light distribution without causing brightness unevenness, making the light distribution close to that of an incandescent lamp, thereby realizing the replacement of an incandescent lamp.

The translucent cover 13 is connected to the LED substrate 4 or the housing 10 . The material of the cover 13 may be resin such as polymethyl methacrylate or polycarbonate, or glass may be used. The cover 13 can be either transparent or colored, but in order to increase the uniformity of the light emitted from the lens, it is finally mixed with particles of about 1000nm in size such as silicon dioxide and/or polycarbonate. Has scattering properties. In addition, when glass is used as the material of the cover 13, it is possible to have a scattering characteristic by coating fine particles such as SiO ₂ on the inner surface of the glass. When it is desired to obtain a flickering feeling like a candle flame, the translucent cover 13 may not have scattering properties.

The frame body 10 also serves as a storage for the circuit 11 and a heat sink for the heat generated in the LED module 2, so it is preferable to use a material with high thermal conductivity such as aluminum or aluminum alloy, copper and other metal materials, but other materials can also be used. In addition, the cavity portion of the housing 10 may be filled with resin such as silicon.

The circuit 11 is used to drive the LED module 2 and has the function of converting AC power into DC power. The circuit 11 is composed of a transformer, a capacitor, and the like, but the configuration of the circuit 11 differs depending on the specifications of the LED module 2 to be used.

For this method, an illumination device installed on a socket for an incandescent lamp is used as an example for description, but the above-mentioned lens is not limited to be used for the incandescent lamp, and can also be applied to other types of illumination devices, as described in the scope of the claim Items can be implemented in various forms.

In addition, in the above embodiments, the surface-mounted LED module 2 is used as the light source, but it is not limited to this, and other types of LEDs and other light emitting elements such as organic EL and inorganic EL can also be used.

Example 2

In this second embodiment, another embodiment of the first embodiment will be described. Fig. 6 is a cross-sectional view viewed from the side of a light emitting unit according to Example 2 of the present invention. The material and manufacturing method of the lens are the same as in Example 1. In addition, the flat portion a, the concave surface b, the refractive surface c, the curved surface d, and the curved surface e have the same configuration as the lens 1 of the first embodiment. In the lens 300 , a configuration different from that of the lens 1 is a truncated conical concave portion g provided on a surface opposite to the light emitting surface 3 of the LED module 2 . The concave part g has a side surface g1 and a bottom surface g2. The recess g has a truncated cone shape whose cross-sectional area decreases from the light emitting surface side to the front. The bottom surface g2 as a flat portion is provided on the opposite surface of the light emitting surface 3 so that g2 as a flat portion faces a, and the amount of light from g2 to a can be increased. The concave portion g has a flat portion in a direction perpendicular to the optical axis 5 , but may have another shape, for example, a hemispherical shape that draws a parabola. If it is hemispherical, light can be bent more uniformly by refraction. In addition, in order to prevent excessive emission of light forward, it is preferable that the size X ₃ of the bottom portion g2 of the concave portion g is smaller than the size X ₄ of the light emitting surface 3 . The size ratio of X ₃ and X ₄ is preferably about 2:3 when considering that the light is incident on the concave surface b. However, other ratios may be used as long as the curved surface of the concave surface b is adjusted to control the emission of light to the rear.

Example 3

In this third embodiment, another embodiment of the first embodiment will be described. Fig. 7(a) is a cross-sectional view viewed from the side of the light emitting unit according to Example 3 of the present invention. The material and manufacturing method of the lens are the same as in Example 1. In addition, the flat portion a, the concave surface b, the refractive surface c, the curved surface d, and the curved surface e have the same configuration as the lens 1 of the first embodiment. The lens 400 differs from the lens 100 in that it has a conical recess f on the surface facing the LED module 2 , and there are also a plurality of conical recesses h. By providing a plurality of conical recesses h, refraction occurs in the recesses h, and the uniformity of light hitting the funnel-shaped concave surface b is increased. As a result, the uniformity of light distribution becomes better. FIG. 7( b ) shows an isometric view of the lens 400 . A plurality of conical recesses h are concentrically arranged. The arrangement of the plurality of conical recesses h is desirably symmetrical when viewed with the optical axis 5 as the center line in order to spread the light uniformly. The conical recess f shown in FIG. 7( a ) may also be a truncated conical shape as in Example 2 or a hemispherical shape that draws a parabola. In addition, although the plurality of conical recesses h are shown as conical shapes in FIG. 7 , they may be in other shapes, such as a Mt.

Example 4

In this fourth embodiment, another embodiment of the first embodiment will be described. 8 is a cross-sectional view viewed from the side of a light emitting unit according to Embodiment 4 of the present invention. The material and manufacturing method of the lens are the same as in Example 1. It is characterized in that the end of the substrate 150 on which the LED module 2 is mounted is bent to a position lower than the surface on which the LED module 2 is mounted. In the planar substrate 4, the light from the LED module 2 is scattered at the end of the substrate 4, so the amount of emitted light to the rear is reduced, but if the substrate 150 is used, the light to the rear will not be blocked, so the direction of light can be increased. Rear exit volume. The material of the substrate 150 is preferably a material with high thermal conductivity and easy processing such as aluminum or an aluminum alloy. When the end of the substrate 150 and the frame body 151 are bonded, thermal conductivity becomes better.

Example 5

In this fifth embodiment, another embodiment of the first embodiment will be described. Fig. 9 is a cross-sectional view seen from the side when Example 5 of the present invention is used as an incandescent lamp. In Embodiment 1, the lens is fixed to the substrate 4 , but in this embodiment, the lens 500 is fixed to the cover 50 . By separating the distance between the LED module 2 and the lens, it is possible to prevent the lens 500 from deteriorating due to heat generation. In addition, since the emission position of light is located at the upper part compared with Example 1, the emission of light to the rear can be increased.

The material and manufacturing method of the lens 500 are the same as those of the first embodiment. It is preferable to use a transparent adhesive to fix the lens 500 to the cover 50 so as to prevent the lens 500 from being projected on the cover 50 as a shadow. As examples of the transparent adhesive, adhesives such as silicone, acrylic, cycloaliphatic epoxy, and polyurethane can be used, but other adhesives can also be used. Furthermore, the lens 500 can be fabricated integrally with the cover 50 using a number of well-known techniques such as light modeling and casting. When integrally formed, the lens 500 and the cover 50 are preferably made of the same material, but they may be made of different materials.

Claims (4)

1. A lighting device having a substrate, an illuminant disposed on the upper side of the substrate, and a lens covering the illuminant, characterized in that, The above-mentioned lens has a surface opposite to the light-emitting surface of the above-mentioned illuminant, and a surface that is concave inward of the above-mentioned lens on the opposite side of the surface opposite to the light-emitting surface of the above-mentioned illuminant, The surface concave to the inside of the above-mentioned lens has an inclination from the bottom of the surface concave to the inside of the above-mentioned lens towards the top and swells above the above-mentioned lens, and has the ability to make the incident from the surface opposite to the light-emitting surface of the above-mentioned illuminant The light entering the above-mentioned lens has a function of emitting to the upper side of the above-mentioned lens, and a function of reflecting to the side and the lower side of the above-mentioned lens, A part of the surface opposite to the light-emitting surface of the above-mentioned illuminant is provided with a concave portion that is concave inwardly of the above-mentioned lens, The concave portion has a shape in which light incident into the lens from the concave portion is reflected more toward the side and lower side of the lens than emitted toward the upper side of the lens by a surface concave toward the inner side of the lens. 2. The lighting device according to claim 1, characterized in that, A flat portion is formed at the bottom of the surface concaved inwardly of the lens. 3. The lighting device according to claim 1 or 2, characterized in that, The concave portion is substantially conical, and the area of the opening of the concave portion on the surface facing the light-emitting surface of the light-emitting body is 1/2 or less of the area of the light-emitting surface of the light-emitting body. 4. A lighting device having a substrate, a plurality of semiconductor light emitting elements arranged above the substrate, and a lens arranged above the substrate to cover the semiconductor light emitting elements, characterized in that, The above-mentioned lens includes an upper part, a side part and a bottom part, said bottom has a first face of said lens, The side portion has a second surface and a third surface of the lens, The above-mentioned upper part has the fourth surface and the fifth surface of the above-mentioned lens, The above-mentioned first surface is a hemispherical curved surface concave inwardly of the above-mentioned lens, and is arranged to cover the above-mentioned semiconductor light-emitting element, One end of the second surface is connected to an end of the first surface, and the second surface is a curved surface covering a side portion of the first surface, One end of the third surface is connected to the other end of the second surface, One end of the above-mentioned fourth surface is connected to the other end of the above-mentioned third surface, and the above-mentioned fourth surface is a curved surface concave inwardly of the above-mentioned lens, The fifth surface is connected to the other end of the fourth surface and is a surface substantially parallel to the substrate, The light from the above-mentioned semiconductor light-emitting element is incident into the above-mentioned lens from the above-mentioned first surface, The light incident from the first surface is directed toward the second surface, the third surface, the fourth surface, and the fifth surface, The second surface refracts the light incident from the first surface toward the upper side of the lighting device and emits it from the lens, The third surface reflects the light incident from the first surface toward the fourth surface in the lens, and the light reflected from the fourth surface is refracted toward a side surface and a lower side of the lighting device, and is emitted from the lens. , The fourth surface reflects the light incident from the first surface toward the third surface in the lens, refracts the light reflected from the third surface toward the upper side of the lighting device, and emits it from the lens, The fifth surface makes the light incident from the first surface to be emitted from the lens toward the upper side of the lighting device, On the first surface, there is a concave portion concave inwardly of the lens, More light incident on the concave portion from the semiconductor light emitting element goes toward the fourth surface than toward the fifth surface.