JP5695457B2 - Lamp - Google Patents

Description

  The present invention relates to a lamp.

  2. Description of the Related Art Conventionally, as a lamp used for a vehicle signal lamp, a general illumination lamp, or the like, a lamp that guides light from an LED (light emitting diode) with a light guide and emits light from a light emitting surface of the light guide is known.

  As this type of lamp, for example, in the one described in Patent Document 1, a light guide disposed in front of the LED is opposed to the light emitting surface of the LED, and a central incident surface disposed on the optical axis of the LED. A prism formed around the central entrance surface, a central exit surface formed corresponding to the central entrance surface on a surface opposite to the central entrance surface, and a prism around the central exit surface And a surrounding emission surface formed.

  In the lamp described in Patent Document 1, among the light emitted from the light emitting surface of the LED, the light emitted along the optical axis within a predetermined angle range from the optical axis is transmitted from the central incident surface into the light guide. And exits from the central exit surface. Of the light emitted from the light emitting surface of the LED, the light emitted in an oblique direction with a predetermined angle or more from the optical axis enters the light guide from the prism and exits from the surrounding light emitting surface. As described above, in the lamp described in Patent Document 1, light emitted from the LEDs is widely incident on the light guide, thereby causing the light emitting surface (the entire light emitting surface) to emit light widely.

JP 2010-165484 A

  By the way, the light emitted from the LED generally has a luminous flux distributed according to the emission angle with respect to the optical axis. Specifically, the light beam decreases as the light exit angle is larger (outgoing from the optical axis in an oblique direction).

  For this reason, in the lamp described in Patent Document 1, the central incident surface located on the optical axis of the LED causes more light flux to enter the light guide than the surrounding prism. Will emit more light flux than the surrounding light exit surface. Therefore, in the lamp described in Patent Document 1, the central emission surface emits light brighter than the peripheral emission surface, and conversely, the peripheral emission surface emits light brighter than the central emission surface. The contour cannot be emphasized.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the lamp | ramp which can light-emit the periphery of a light emission surface brighter than a center part, taking in the light from LED widely.

In order to solve the above-mentioned problem, the invention described in claim 1
An LED with its optical axis facing forward,
A light guide disposed in front of the LED;
In a lamp comprising:
The light guide is
A first incident that is provided on the rear surface of the light guide so as to be positioned on the optical axis so as to face the LED, and allows the light emitted from the LED to enter the light guide while being parallel light forward. And
Provided around the first incident portion of the rear surface and incident on the light guide body while making the light emitted from the LED toward the side of the first incident portion as parallel light forward. A second incident part to be made,
Provided in front of the first incident portion of the front surface of the light guide so as to spread light incident on the light guide from the first incident portion in a plurality of directions orthogonal to the optical axis. A first reflecting surface for internal reflection;
A second reflection surface provided around the second incident portion of the rear surface, and internally reflecting light internally reflected by the first reflection surface;
A central emission surface that is provided in front of the second incident portion of the front surface and emits light incident on the light guide from the second incident portion;
A surrounding emitting surface that is provided around the central emitting surface of the front surface and emits light internally reflected by the second reflecting surface from the light guide;
I have a,
The central emission surface is formed from each side parallel to a first optical axis orthogonal direction orthogonal to the optical axis and a second optical axis orthogonal direction orthogonal to both the optical axis and the first optical axis orthogonal direction. Formed into a substantially rectangular shape,
The surrounding emission surface is formed in a substantially square ring shape composed of two sides elongated along the direction orthogonal to the first optical axis and two sides elongated along the direction orthogonal to the second optical axis.
The first reflecting surface has a 45 degree angle with respect to the optical axis in four directions, ie, both sides in the orthogonal direction of the first optical axis and both sides in the orthogonal direction of the second optical axis, with a point on the optical axis as a base point. There are four individually inclined at an angle,
The light guide is provided at four locations on the periphery of the light guide and located on both sides of the first reflecting surface in the direction perpendicular to the first optical axis and on both sides in the direction perpendicular to the second optical axis. The light internally reflected by the four first reflecting surfaces to both sides of the first optical axis orthogonal direction or the second optical axis orthogonal direction is respectively the second optical axis orthogonal direction or the first optical axis orthogonal direction. 4 pairs of branched reflecting surfaces for internal reflection to both sides of the
A plurality of the second reflecting surfaces are provided on both sides in the longitudinal direction of each of the four pairs of branched reflecting surfaces along the longitudinal direction of the surrounding light emitting surface, and after being internally reflected by the four first reflecting surfaces, The light internally reflected by the four pairs of branch reflecting surfaces is individually internally reflected forward .

  According to the present invention, among the light emitted from the LED, the light having a small emission angle from the optical axis enters the light guide while being converted into parallel light forward through the first incident portion facing the LED, After being internally reflected by the first reflecting surface so as to spread in a plurality of directions perpendicular to the optical axis and internally reflected forward by the second reflecting surface, it is emitted from the surrounding emitting surface provided around the central emitting surface. On the other hand, among the light emitted from the LED, light having a large emission angle from the optical axis is incident on the light guide body as being parallel light forward through the second incident part provided around the first incident part. And exits from the central exit surface. Therefore, while the light from the LED is widely taken in by the first incident part and the second reflecting surface, the surrounding light exiting surface can be caused to emit light with a light having a smaller exit angle than the light that emits light from the central exit surface and with a large amount of light flux. As a result, the peripheral part of the light emitting surface (peripheral outgoing surface) can be made to emit light brighter than the central part (central outgoing surface).

It is a front view of the lamp in embodiment. It is a rear view of the lamp in embodiment. It is sectional drawing in the AA of FIG. It is sectional drawing in the BB line of FIG. It is sectional drawing in the CC line of FIG. It is sectional drawing in the DD line | wire of FIG. It is a figure for demonstrating the optical path in the lamp in embodiment. It is a figure for demonstrating the optical path in the lamp in embodiment. It is a figure for demonstrating the optical path in the lamp in embodiment. It is a figure for demonstrating the optical path in the lamp in embodiment. It is a figure for demonstrating the optical path in the lamp in embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 is a front (front) view of the lamp 1 in the present embodiment, FIG. 2 is a rear (rear) view of the lamp 1, and FIGS. 3 to 6 are AA to D in FIG. It is each sectional drawing in the -D line.
In the following description, the descriptions “front” and “rear” refer to the direction viewed from the lamp 1. Further, a direction along the front-rear direction of the lamp 1 is referred to as a “Z direction”, and two directions orthogonal to the Z direction and orthogonal to each other are referred to as an “X direction” and a “Y direction”.

As shown in FIGS. 1 to 4, the lamp 1 includes an LED (light emitting diode) 2 and a light guide 3 disposed in front of the LED 2.
Among these, LED2 is arrange | positioned in the state which orient | assigned the optical axis Ax to the front, and radiate | emits the light which has a Lambertian directivity centering on the said optical axis Ax ahead. Specifically, the light emitted from the LED 2 has a smaller luminous flux as the emission angle from the optical axis Ax is larger (outward from the optical axis Ax and obliquely forward).

  The light guide 3 emits light by guiding the light emitted from the LED 2 and is formed in a substantially flat plate shape orthogonal to the Z direction. The light guide 3 is disposed so as to surround the periphery along the side surface of the central portion 3a, which is formed in a square front view shape including sides parallel to the X direction and the Y direction. And a peripheral portion 3b formed in a substantially quadrangular annular shape in front view.

In the central portion 3a of the light guide 3, a first incident portion 31, a plurality of second incident portions 32,..., Four first reflecting surfaces 33,. .
Among these, the 1st incident part 31 is formed in the substantially cylindrical shape centering on the optical axis Ax, and is protrudingly provided by the rear surface of the center part 3a so that LED2 may be located on the optical axis Ax. A convex (aspheric) first incident surface 311 that bulges rearward is formed at the rear end of the first incident portion 31 so as to face the LED 2 with the optical axis Ax as a rotational symmetry axis. The first incident surface 311 is disposed so that the LED 2 is located at the focal point thereof, and the light emitted from the LED 2 has an emission angle less than a half-value angle (an angle half the maximum emission angle). The light is refracted in the direction along the optical axis Ax and is incident on the light guide 3 while being parallel light forward.

  The second incident portions 32,... Are provided over the entire periphery of the first incident portion 31 in the rear surface of the central portion 3a, and are formed concentrically with different diameters around the optical axis Ax. Each of the second incident portions 32 is a prism portion protruding rearward so that the radiation cross section has a substantially triangular shape. Among these, the surface close to the optical axis Ax is the first portion of the light emitted from the LED 2. A second incident surface 321 through which light directed to the side of the first incident portion 31, that is, light having an emission angle equal to or greater than a half-value angle, enters the light guide 3. The second incident surface 321 stands substantially vertically downward, and more specifically, slightly inclines to the side as a draft from the mold when the light guide 3 is molded. On the other hand, the surface farther from the optical axis Ax in the second incident portion 32 has a prism reflecting surface 322 that internally reflects light incident from the second incident surface 321 into the light guide 3 in the direction along the optical axis Ax. It has become. Therefore, the second incident portion 32 guides light emitted from the LED 2 toward the side from the first incident portion 31, that is, light having an emission angle of a half-value angle or more as parallel light forward. Incident into the body 3.

  The first reflecting surfaces 33 are provided in front of the first incident portion 31 in the front surface of the central portion 3a. The first reflecting surfaces 33,... Are individually inclined at an angle of 45 degrees with respect to the optical axis Ax in four directions, ie, both sides in the X direction and both sides in the Y direction, starting from a point on the optical axis Ax. Four triangular planes are connected to each other with the adjacent first reflecting surfaces 33 so as to form a peripheral surface of a regular square pyramid that is vertically inverted with its apex positioned on the optical axis Ax. With such a configuration, the first reflecting surfaces 33,... Receive light that has entered the light guide 3 from the first incident portion 31 into four in the X direction and on both sides in the Y direction with the optical axis Ax as a boundary. Internal reflection is performed so as to be branched equally in the direction.

  The central exit surface 34 is provided on the entire front surface of the central portion 3a around the first reflecting surfaces 33, that is, in front of the second incident portion 32 in the front surface of the central portion 3a. The central exit surface 34 emits light that has entered the light guide 3 from the second incident portion 32 from within the light guide 3. In addition, a lens cut for diffusing outgoing light is formed on the central outgoing surface 34 over the entire surface.

In the peripheral portion 3 b of the light guide 3, four pairs of branched reflection surfaces 35,..., A plurality of second reflection surfaces 36,.
Among these, the four pairs of branched reflecting surfaces 35,... Are two pairs of branched reflecting surfaces 35a,... And the first reflecting surfaces 33,. It is comprised from two pairs of branch reflective surfaces 35b and ... located in two places of the both sides of a Y direction. Among these, the two pairs of branched reflection surfaces 35a,... Are at an angle of 45 degrees with respect to the X direction, with the base line being the intersection of the line obtained by shifting the optical axis Ax in the X direction and the side end surface of the central portion 3a. Each pair is configured as a pair of planes that are individually inclined to both sides in the Y direction. The branched reflection surfaces 35a,... Divide the light internally reflected to both sides in the X direction by two surfaces inclined to both sides in the X direction among the first reflection surfaces 33,. To be internally reflected. On the other hand, the two pairs of branched reflecting surfaces 35b,... Are X at an angle of 45 degrees with respect to the Y direction, with the base line being the intersection of the line obtained by shifting the optical axis Ax in the Y direction and the side end surface of the central portion 3a. It is each comprised as a pair of plane which inclines to the both sides of a direction separately. The branched reflection surfaces 35b,... Divide the light internally reflected to both sides in the Y direction by two surfaces inclined to both sides in the Y direction among the first reflection surfaces 33,. To be internally reflected.

  As shown in FIGS. 2, 5, and 6, the second reflecting surfaces 36,... Are provided around the second incident portions 32, of the rear surface of the light guide 3, that is, on the rear surface of the peripheral portion 3b. More specifically, it is provided in a portion excluding the four places where the branch reflecting surfaces 35,. The second reflection surfaces 36,... Are second reflection surfaces 36a,... Provided in a portion elongated in the Y direction and the second reflection provided in a portion elongated in the X direction. It has the surface 36b. The rear surface of the peripheral portion 3b provided with any of the second reflecting surfaces 36,... Is also formed in a step shape along the longitudinal direction (X direction or Y direction) of the peripheral portion 3b. It is formed so as to be positioned forward stepwise as it goes to the end (corner) of the peripheral portion 3b while being orthogonal to the direction. Each of the second reflecting surfaces 36 forms a stepped surface that is alternately connected in the longitudinal direction of each of the step surfaces and the peripheral portion 3b, and is inclined at an angle of 45 degrees with respect to the longitudinal direction of the peripheral portion 3b. ing. However, the second reflecting surfaces 36a,... Provided in a portion elongated in the Y direction in the peripheral portion 3b are formed up to the end portion in the Y direction of the light guide 3, while the X direction in the peripheral portion 3b. The second reflecting surfaces 36b,... Provided in the long part are formed only up to the end of the central part 3a. As described above, the second reflecting surfaces 36,... Are provided on both sides of the pair of branch reflecting surfaces 35, 35 (both sides in the longitudinal direction of the peripheral portion 3b) in each of the four long portions of the peripheral portion 3b. That is, it is divided into 8 groups. Further, the range (position and length) in the Z direction of the second reflecting surfaces 36,... Of each group coincides with the range (position and length) in the Z direction of the branched reflecting surfaces 35,. With such a configuration, the second reflection surfaces 36 are internally reflected by the first reflection surfaces 33, and are branched and internally reflected by the branch reflection surfaces 35,... To both sides in the X direction or both sides in the Y direction. The reflected light is individually internally reflected forward.

  The peripheral light exit surfaces 37 are provided around the central light exit surface 34 in the front surface of the light guide 3, that is, on the front surface of the peripheral portion 3b, and more specifically, the branched reflection surface 35 of the front surface of the peripheral portion 3b. ,... Are provided at the forward projecting portions except for the four places where the. Therefore, the peripheral light exit surfaces 37,... As a whole have a shape that substantially matches the front view shape of the peripheral portion 3b, that is, the long sides along the X direction and the long sides along the Y direction. It is formed in a substantially square ring shape consisting of two sides. The surrounding light emitting surfaces 37,... Are located in front of the second reflecting surfaces 36,..., And the surrounding light emitting surfaces 37a,... Located in front of the second reflecting surfaces 36a,. It is comprised from the surrounding light emission surface 37b located in front of the surface 36b. Each of the surrounding light emitting surfaces 37,... Is formed in a planar shape orthogonal to the Z direction, and the light internally reflected forward by the second reflecting surfaces 36,.

Then, the light emission aspect of the lamp 1 is demonstrated.
7-11 is a figure for demonstrating the optical path in the lamp 1, and has shown each part shown in FIG. 1, FIG.

  As shown in these drawings, among the light emitted from the LED 2, the light L <b> 1 whose emission angle is less than the half-value angle enters the light guide 3 through the first incident surface 311 while being converted into parallel light forward. . The light L1 travels forward from the first incident surface 311 and enters the four first reflecting surfaces 33,..., And the first reflecting surfaces 33,. The light is internally reflected while being branched in four directions with both sides.

  Among these, the light L11 and the light L12 branched to both sides in the X direction by the first reflecting surfaces 33,... Travel to both sides in the X direction and enter the pair of branch reflecting surfaces 35a,. ,... Are internally reflected while being branched to both sides in the Y direction. Thus, the light L11 is branched into the light L111 and the light L112, and the light L12 is branched into the light L121 and the light L122. The light L111, L112, L121, L122 travels from the branch reflecting surface 35a,... To both sides in the Y direction, enters the second reflecting surface 36a,. .. Are scattered in the Y direction by the surfaces 36a,. And when these light L111, L112, L121, L122 is radiate | emitted ahead from the surrounding radiation | emission surface 37a, ..., the said circumference | surroundings emission surface 37a, ... will light-emit.

  On the other hand, the light L13 and the light L14 branched to both sides in the Y direction by the first reflecting surfaces 33,... Travel to both sides in the Y direction and enter the pair of reflecting surfaces 35b,. Are internally reflected while being branched to both sides in the X direction. Thus, the light L13 is branched into the light L131 and the light L132, and the light L14 is branched into the light L141 and the light L142. The light L131, L132, L141, L142 proceeds from the branch reflection surface 35b,... To both sides in the X direction, enters the second reflection surface 36b,..., And the second reflection is intermittently distributed in the X direction. Are internally reflected individually forward while being dispersed in the X direction by the surfaces 36b,. Then, when these lights L131, L132, L141, and L142 are emitted forward from the surrounding emission surfaces 37b,..., The surrounding emission surfaces 37b,.

  Of the light emitted from the LED 2, the light L <b> 2 having an emission angle equal to or greater than the half-value angle enters the light guide 3 through the second incident portions 32,. More specifically, the light L2 is incident on the light guide 3 while being refracted laterally through the second incident surfaces 321,... And then internally reflected forward by the prism reflecting surfaces 322,. The light L2 travels forward from the second incident portion 32 and exits forward from the central exit surface 34, whereby the central exit surface 34 emits light.

  As described above, in the lamp 1, the light L1 having a small emission angle from the LED 2 is divided into eight lights L111 to L142 to emit the peripheral emission surfaces 37,. The light is emitted. Therefore, the surrounding light emitting surfaces 37,... Can be caused to emit light by the light L1 having a larger luminous flux than the light L2 that emits light from the central emitting surface 34. As a result, the surrounding light emitting surfaces 37,. be able to.

  As described above, according to the lamp 1, the light from the LED 2 is taken into the light guide 3 over a wide range of emission angles by the first incident portion 31 and the second reflection surface 32, and the central emission surface 34. Can be emitted by the light L1 having an emission angle smaller than that of the light L2 that emits light and a large amount of light flux. Therefore, it is possible to make the surrounding light emitting surfaces 37,... Emit light brighter than the central light emitting surface 34 while capturing light from the LEDs 2 widely.

  Further, since the square central emission surface 34 and the substantially square annular peripheral emission surfaces 37,... Provided around the center emission surface 34 can emit light, a simple circular light emission surface corresponding to the shape of the LED can be provided. Unlike the conventional case where light is emitted, the design at the time of light emission can be made unique.

  The embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

  For example, in the above-described embodiment, among the light emitted from the LED 2, the surrounding light emitting surfaces 37,... However, the threshold of the emission angle that separates the light L1 and the light L2 may not be a half-value angle. Specifically, the threshold value may be changed to a half-value angle or more if it is desired to make the surrounding light exit surfaces 37,. In this case, however, it is needless to say that the size and position of the first incident portion 31, the second incident portion 32, the first reflecting surface 33,.

Further, the rectangular central emission surface 34 and the substantially square annular peripheral emission surfaces 37 provided around the central emission surface 34 are caused to emit light. However, the central emission surface 34 and the peripheral emission surface 37 are circular. May be. In this case, for example, the first reflecting surface 33 is formed in a conical circumferential surface so that the light internally reflected by the first reflecting surface 33 is spread in the XY plane, and the branch reflecting surfaces 35,. It is only necessary that the light from the first reflection surface 33 is directly internally reflected by the second reflection surface 36 forward.
Further, the central exit surface 34 and the surrounding exit surface 37 may have a polygonal shape other than a quadrangle.

1 Light 2 LED
Ax optical axis 3 light guide 3a central portion 31 first incident portion 311 first incident surface 32 second incident portion 321 second incident surface 322 prism reflecting surface 33 first reflecting surface 34 central emitting surface 3b peripheral portions 35, 35a, 35b Branch reflection surface 36, 36a, 36b Second reflection surface 37, 37a, 37b Ambient emission surface L1 light (light with a small emission angle)
L2 light (light with a large emission angle)
X direction (first optical axis orthogonal direction)
Y direction (second optical axis orthogonal direction)

Claims (1)

An LED with its optical axis facing forward,
A light guide disposed in front of the LED;
In a lamp comprising:
The light guide is
A first incident that is provided on the rear surface of the light guide so as to be positioned on the optical axis so as to face the LED, and allows the light emitted from the LED to enter the light guide while being parallel light forward. And
Provided around the first incident portion of the rear surface and incident on the light guide body while making the light emitted from the LED toward the side of the first incident portion as parallel light forward. A second incident part to be made,
Provided in front of the first incident portion of the front surface of the light guide so as to spread light incident on the light guide from the first incident portion in a plurality of directions orthogonal to the optical axis. A first reflecting surface for internal reflection;
A second reflection surface provided around the second incident portion of the rear surface, and internally reflecting light internally reflected by the first reflection surface;
A central emission surface that is provided in front of the second incident portion of the front surface and emits light incident on the light guide from the second incident portion;
A surrounding emitting surface that is provided around the central emitting surface of the front surface and emits light internally reflected by the second reflecting surface from the light guide;
I have a,
The central emission surface is formed from each side parallel to a first optical axis orthogonal direction orthogonal to the optical axis and a second optical axis orthogonal direction orthogonal to both the optical axis and the first optical axis orthogonal direction. Formed into a substantially rectangular shape,
The surrounding emission surface is formed in a substantially square ring shape composed of two sides elongated along the direction orthogonal to the first optical axis and two sides elongated along the direction orthogonal to the second optical axis.
The first reflecting surface has a 45 degree angle with respect to the optical axis in four directions, ie, both sides in the orthogonal direction of the first optical axis and both sides in the orthogonal direction of the second optical axis, with a point on the optical axis as a base point. There are four individually inclined at an angle,
The light guide is provided at four locations on the periphery of the light guide and located on both sides of the first reflecting surface in the direction perpendicular to the first optical axis and on both sides in the direction perpendicular to the second optical axis. The light internally reflected by the four first reflecting surfaces to both sides of the first optical axis orthogonal direction or the second optical axis orthogonal direction is respectively the second optical axis orthogonal direction or the first optical axis orthogonal direction. 4 pairs of branched reflecting surfaces for internal reflection to both sides of the
A plurality of the second reflecting surfaces are provided on both sides in the longitudinal direction of each of the four pairs of branched reflecting surfaces along the longitudinal direction of the surrounding light emitting surface, and after being internally reflected by the four first reflecting surfaces, A lamp characterized in that the light internally reflected by the four pairs of branch reflecting surfaces is individually internally reflected forward .

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