JP2018013680A - Optical lens - Google Patents

Abstract

An object of the present invention is to provide an optical lens capable of efficiently performing light distribution control and improving marketability by providing uniform lighting feeling. A light guide includes an incident part, an emitting part provided on the opposite side of the incident part, and a light guiding part for guiding the light incident from the incident part to the emitting part. The portion 4 includes a first reflecting surface 41 that totally reflects part of the light incident from the incident portion 2 in the direction of the optical axis x, and a second reflecting surface 41 that totally reflects the light in the direction of the optical axis x in a direction orthogonal to the optical axis x. A reflecting surface 42 and a plurality of stepped third reflecting surfaces 43 for totally reflecting the light totally reflected by the second reflecting surface 42 toward the output unit 3 in the direction of the optical axis x. In the optical lens 1 formed with a plurality of flute cuts 3a along the arrangement direction of the third reflecting surfaces 43, the arrangement pitch p of the plurality of third reflecting surfaces 43 and the arrangement pitch p of the plurality of flute cuts 3a are matched. , the center of each third reflecting surface 43 is aligned with the center of each flute cut 3a. [Selection drawing] Fig. 2

Description

  The present invention relates to an optical lens that emits light from the entire emission part by emitting light from the emission part while totally reflecting light incident from a light source.

  For example, LEDs (light emitting diodes) are being used instead of conventional bulbs (light bulbs) as light sources for vehicle signal lights such as tail lamps and stop lamps. This LED has high luminous efficiency and long life and has advantages such as power saving, but emits light with high directivity, and therefore has a problem that the light cannot be used as it is. For this reason, normally, light having a high directivity emitted from the LED is made incident on an optical lens having a high light transmittance, and light is emitted from the emission part by reflection in the process of guiding the light in the optical lens. The whole is made to emit light.

  Incidentally, with respect to such an optical lens, Patent Document 1 proposes an optical lens shown in FIG.

  That is, FIG. 4 is a longitudinal sectional view of the optical lens proposed in Patent Document 1, and the illustrated optical lens 101 is disposed in front of the light emitting direction of the LED 110 that is a light source (upward in FIG. 4), and is arranged on the LED 110 side. An incident portion 102 protruding from one surface (lower surface in FIG. 4), an emitting portion 103 provided on the other surface (upper surface in FIG. 4) opposite to the one surface, and the incident portion 102. A light guide unit 104 that guides the light incident from the light source to the emission unit 103.

  Here, the light guide unit 104 includes a first reflecting surface 141 that totally reflects a part of light incident from the incident unit 102 in the optical axis x direction (vertically upward in FIG. 4), and light in the optical axis x direction. And a pair of second reflecting surfaces 142 that totally reflect in the direction orthogonal to the optical axis x (the left-right direction in FIG. 4), and the light that is totally reflected by the second reflecting surface 142 in the direction of the optical axis x to the emitting unit 103 A plurality of step-like third reflecting surfaces 143 for total reflection are provided. A plurality of flute cuts 103a are formed in the emitting portion 103 along the arrangement direction on the third reflecting surface 143. The incident portion 102 includes a convex first incident surface 121 and a second incident surface 122 formed around the first incident surface 121.

  In such an optical lens 101, when the LED 110 is activated and emits light, a part of the light is incident on the optical lens 101 while being refracted in the optical axis x direction by the first incident surface 121 of the incident portion 102. The other light enters the optical lens 101 from the second incident surface 122 and is totally reflected by the first reflecting surface 141 toward the second reflecting surface 142. Then, the light traveling toward the second reflecting surface 142 in the optical lens 101 is totally reflected in the direction orthogonal to the optical axis x while being branched left and right by the pair of second reflecting surfaces 142 with the optical axis x as a boundary. 3 Head to the reflecting surface 143.

  In the optical lens 101, the light traveling toward the third reflecting surface 143 is totally reflected by each of the plurality of third reflecting surfaces 143, travels toward the emitting portion 103 along the optical axis x direction, and is formed in the emitting portion 103. Since the light is emitted out of the optical lens 101 while being diffused by the plurality of flute cuts 103a, the emission unit 103 emits light in a line shape.

JP 2011-228185 A

  However, in the optical lens 101 proposed in Patent Document 1, as shown in detail in FIG. 5, a plurality of light diffusing flute cuts 103 a are laid out by dividing the area of the exit surface evenly in the exit portion 103. Therefore, the positional relationship between the plurality of third reflecting surfaces 143 that totally reflect the light toward the emitting portion 103 in the direction of the optical axis x and the flute cut 103a vary depending on the location. For this reason, if the flute shape of the flute cut 103a is formed with the same R value (curvature radius), the aiming angle (light distribution angle) changes for each flute cut 103a, and light distribution control cannot be performed efficiently. There is a problem that the merchantability of the optical lens 101 is lowered because the lighting feeling is not uniform.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical lens capable of efficiently performing light distribution control and improving the merchantability by providing a lighting feeling. There is.

In order to achieve the above-described object, the invention according to claim 1 is arranged in front of the light emitting direction of the light source and protrudes from one surface on the light source side and the other side opposite to the one surface. And a light guide part that guides the light incident from the incident part to the emission part,
The light guide unit includes a first reflection surface that totally reflects a part of light incident from the incident unit in an optical axis direction, and a second reflection surface that totally reflects light in the optical axis direction in a direction orthogonal to the optical axis. And a plurality of step-like third reflecting surfaces that totally reflect the light totally reflected by the second reflecting surface toward the emitting portion in the optical axis direction,
In the optical lens formed by forming a plurality of flute cuts along the arrangement direction of the third reflecting surface in the emitting portion,
The arrangement pitch of the plurality of third reflection surfaces and the arrangement pitch of the plurality of flute cuts formed in the emitting portion are matched, and the center of each third reflection surface is matched with the center of each flute cut. And

  According to a second aspect of the present invention, in the first aspect of the present invention, a base offset surface is set at a position offset in parallel to the light emitting direction from the base surface of the light emitting portion, and the third reflection on the base offset surface. The flute shape of the flute cut is set in the light irradiation range from the surface, and the flute shape is extended to another region to form a plurality of flute cuts.

  According to the present invention, in the optical lens, the arrangement pitch of the plurality of third reflection surfaces that totally reflect light in the optical axis direction toward the emission portion is matched with the arrangement pitch of the plurality of flute cuts formed in the emission portion, Since the center of each third reflecting surface and the center of each flute cut are matched, the aiming angles (light distribution angles) by each flute cut are all equal, and light distribution control by flute cut can be performed efficiently, Since the lighting feeling is uniform, the merchantability of the optical lens can be improved.

1 is a perspective view of an optical lens according to the present invention. It is a longitudinal cross-sectional view of the optical lens which concerns on this invention. It is a principal part expanded sectional view of FIG. It is a longitudinal cross-sectional view of the optical lens proposed in Patent Document 1. It is a principal part expanded sectional view of FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a perspective view of an optical lens according to the present invention, FIG. 2 is a longitudinal sectional view of the optical lens, and FIG. 3 is an enlarged sectional view of a main part of FIG.

  The optical lens 1 according to the present embodiment is integrally formed of a transparent resin such as acrylic or polycarbonate having high light transmittance, and as shown in FIG. 2, the light emitting direction front of the LED 10 that is a light source (FIG. 2). 2 is disposed on the LED 10 side and is provided on the other surface (upper surface in FIG. 2) opposite to the one surface. The light emitting unit 3 and the light guide unit 4 that guides the light incident from the incident unit 2 to the light emitting unit 3. Note that the LED 10 that is a light source is disposed so as to emit light upward in FIG. 2, and the optical lens 1 is formed in a bilaterally symmetric shape with the optical axis x of the LED 10 as the center.

  As shown in FIGS. 2 and 3, the incident portion 2 is formed in a truncated conical shape with the optical axis x as a rotationally symmetric axis, and the head of the incident portion 2 has an LED 10 side (FIG. 2). And the recessed part 2a opened toward the downward direction of FIG. 3 is formed. And the convex-shaped (aspherical) 1st entrance surface 21 which bulges toward LED10 side is formed in the bottom part of this recessed part 2a so that it may oppose LED10 by making optical axis x into a rotational symmetry axis. Yes. Here, the first incident surface 21 is disposed so that the LED 10 is positioned at the focal point, and refracts light emitted from the LED 10 in a direction along the optical axis x (vertically upward in FIGS. 2 and 3). The optical lens 1 has a function of being incident on the optical lens 1.

  Further, the inner peripheral surface of the recess 2a formed at the periphery of the first incident surface 21 constitutes a second incident surface 22, and the second incident surface 22 is erected so as to cover the periphery of the LED 10. It is a conical surface, and has a function of causing the light emitted from the LED 10 toward the side of the first incident surface 21 to enter the optical lens 1.

  The light guide unit 4 includes a first reflection surface 41 that totally reflects light incident from the second incident surface 22 of the incident unit 2 in the optical axis x direction (vertically upward in FIGS. 2 and 3), and an optical axis x. A pair of second reflecting surfaces 42 that totally reflect light in the direction perpendicular to the optical axis x (left and right direction in FIGS. 2 and 3), and horizontal light that is totally reflected by the second reflecting surface 42 as an optical axis. There are provided a plurality of step-like third reflecting surfaces 43 (three on the left and right in the illustrated example) that are totally reflected toward the emitting portion 3 in the x direction.

  Here, the first reflection surface 41 is formed as an outer peripheral surface of the incident portion 2, and the pair of second reflection surfaces 42 are surfaces opposite to the LED 10 of the optical lens 1 (FIGS. 2 and 2). 3 is recessed on the left and right with the optical axis x as the center. Specifically, the pair of second reflecting surfaces 42 are formed as slopes inclined in the left-right direction at an angle of 45 ° with respect to the optical axis x, and the first reflecting surface 21 and the second incident surface 22 It has a function of totally reflecting light incident on the optical lens 1 from side to side about the optical axis x.

  A plurality (three in the illustrated example) of the third reflecting surface 43 is formed on each of the left and right side portions of the surface of the optical lens 1 on the LED 10 side (the lower surface in FIGS. 2 and 3). Specifically, these third reflecting surfaces 43 are formed in a stepped shape with a predetermined arrangement pitch p in the left-right direction, and the light totally reflected in the left-right direction by the second reflecting surface 42 in the optical axis x direction. And has a function of individually totally reflecting the light toward the emitting portion 3.

  The emitting portion 3 is positioned on the side opposite to the LED 10 of the optical lens 1 (shown in FIGS. 2 and 3) so as to be positioned in the optical axis x direction of the third reflecting surface 43 (upward in FIGS. 2 and 3). It is formed on both the left and right sides of the second reflecting surface 42 on the upper surface, and each emitting part 3 has the same number (three) of flutes as the number of the left and right third reflecting surfaces 43 (three in the illustrated example). Cuts 3a are formed at a predetermined arrangement pitch p in the left-right direction. Here, the left and right emitting portions 3 have a function of emitting light that is totally reflected by the third reflecting surface 43 and that is directed toward the emitting portion 3 while being diffused by the flute cut 3a at a predetermined aiming angle (light distribution angle). doing.

  Thus, in the optical lens 1 according to the present embodiment, as shown in FIG. 2, the arrangement pitch p of a plurality of (three each) third reflecting surfaces 43 and a pair of left and right emitting portions 3. The arrangement pitch p of a plurality of (three each) flute cuts 3a formed in the same is made to coincide, and the center of each third reflecting surface 43 is made to coincide with the center of each flute cut 3a.

  In the optical lens 1 configured as described above, when the LED 10 is activated and emits light, a part of the light enters the optical lens 1 while being refracted by the first incident surface 21 in the optical axis x direction. It becomes parallel light and travels toward the second reflecting surface 42. Further, the other light emitted from the first incident surface 21 to the side is incident on the optical lens 1 from the second incident surface 22 and then totally reflected by the first reflecting surface 41 in the optical axis x direction. The light then travels toward the second reflecting surface 42 as parallel light.

  Then, the parallel light traveling toward the second reflecting surface 42 is totally reflected by the pair of left and right second reflecting surfaces 42, is directed left and right about the optical axis x, and is intermittently arranged in the left and right direction. The light is totally reflected in the direction of the optical axis x by the three reflecting surfaces 43, travels toward the pair of left and right emitting portions 3, and is emitted while the light distribution is controlled by a plurality of flute cuts 3 a formed in each emitting portion 3. As a result, in the optical lens 1, the left and right emitting portions 3 emit light in a line shape with the left and right second reflecting surfaces 42 interposed therebetween.

  In the above, according to the optical lens 1 according to the present embodiment, the plurality of third reflection surfaces 43 that are totally reflected in the direction of the optical axis x toward the emission unit 3 are formed on the arrangement pitch p and the emission unit 3. Since the arrangement pitch p of the plurality of flute cuts 3a is matched and the center of each third reflecting surface 43 is matched with the center of each flute cut 3a, all the aiming angles (light distribution angles) of each flute cut 3a are As a result, the light distribution control by the flute cut 3a can be performed efficiently, and the lighting feeling is uniform, so that the merchantability of the optical lens 1 can be improved.

  Here, a method of forming the flute cut 3a on the left and right emitting portions 3 of the optical lens 1 will be described with reference to FIG.

  A base offset surface S ′ is set at a position offset in parallel to the light emitting direction (upward in FIG. 3) from the base surface S of the emitting portion 3, and the light from each third reflecting surface 43 on the base offset surface S ′. The flute shape (R value or free-form surface) of the flute cut 3a is set in the irradiation range (the range of points a and b in FIG. 3), and the flute shape is extended to other regions to form a plurality of flute cuts 3a. Form. In this case, it is necessary to set the offset amount ε of the base offset surface S ′ so that the extended surface does not dive below the base surface S.

  The optical lens according to the present invention is suitable for vehicular lamps, general lighting equipment, game lighting equipment, and the like.

DESCRIPTION OF SYMBOLS 1 Optical lens 2 Incident part 21 1st incident surface 22 2nd incident surface 3 Output part 3a Flute cut 4 Light guide part 41 1st reflective surface 42 2nd reflective surface 43 3rd reflective surface 10 LED (light source)
p 3rd reflecting surface and flute cut arrangement pitch S Base surface S 'Base offset surface x Optical axis ε Offset amount of base offset surface

Claims (2)

An incident part arranged in front of the light emitting direction of the light source and projecting from one surface on the light source side, an emitting part provided on the other surface opposite to the one surface, and incident from the incident portion A light guide part that guides the emitted light to the emission part,
The light guide unit includes a first reflection surface that totally reflects a part of light incident from the incident unit in an optical axis direction, and a second reflection surface that totally reflects light in the optical axis direction in a direction orthogonal to the optical axis. And a plurality of step-like third reflecting surfaces that totally reflect the light totally reflected by the second reflecting surface toward the emitting portion in the optical axis direction,
In the optical lens formed by forming a plurality of flute cuts along the arrangement direction of the third reflecting surface in the emitting portion,
The arrangement pitch of the plurality of third reflection surfaces and the arrangement pitch of the plurality of flute cuts formed in the emitting portion are matched, and the center of each third reflection surface is matched with the center of each flute cut. An optical lens. A base offset surface is set at a position offset in parallel to the light emitting direction from the base surface of the emitting part, and the flute shape of the flute cut is set in the light irradiation range from the third reflecting surface on the base offset surface, respectively. 2. The optical lens according to claim 1, wherein a plurality of flute cuts are formed by setting and extending the flute shape to another region.

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