TW201716722A - Total internal reflection lens - Google Patents

Abstract

A total internal reflection lens comprises a translucent main body which has a annular convex portion surrounding a symmetry axis of the translucent main body, and has a first cavity and a second cavity arranged in the symmetry axis. The first cavity has an upward opening, and the second cavity has a downward opening. The translucent main body provides two light paths which are different in their light incident surfaces, total reflection surfaces and light exit surfaces. A first light path includes a first light incident surface located at an inside wall of the first cavity, an outside total reflection surface connected with a lower edge of the annular convex portion, and a first light exit surface located at a surface of the annular convex portion. A second light path includes a second light incident surface which is convex downward and located at an inside top surface of the first cavity, an inside total reflection surface located at an inside surface of the second cavity and opposite to the outside total reflection surface, and a second light exit surface connected between the inside total reflection surface and the first light exit surface. Angles between the light exit directions of the two light paths and the symmetry axis are in the range of 10 to 30 degrees.

Description

Total reflection lens

The present invention relates to a total reflection lens, and more particularly to a total reflection lens that provides an independent light path that is different from the two entrance surfaces, the total reflection surface, and the exit surface.

Since the general light source has a large illumination angle, it will illuminate many areas that do not need illumination, such as the bottom side of the lamp cover. In order to improve the lighting effect, a total reflection lens is added above the light source to adjust the direction of the light.

Conventional total reflection lenses utilize optical total reflection properties to concentrate the light source in the center of the lens, reducing the angle of illumination, allowing energy to concentrate and transmit further. For example, in FIG. 1, a conventional total reflection lens 100 has a recessed opening 110 that is open to the light source 200. The recessed hole 110 has a convex top surface 112 and an inner side wall 114 as two light incident surfaces, respectively. The light entering from the convex top surface 112 is refracted by the light-emitting surface 130 in the direction of the parallel central axis C ₁ without being totally reflected inside the total reflection lens 100. Entering by the inner sidewall 114 of the light 120 after being reflected in a total reflection surface of the internal total reflection lens 100, in a direction parallel to the central axis C ₁ of the light emitted by the light-receiving surface 130 a.

In addition, there are also total reflection lenses for a wide range of illumination. For example, FIGS. 2A and 2B show a total reflection lens 300 of an amplifiable illumination region disclosed in the prior patent Taiwan Patent No. I368761, which has a function of guiding the formation of side illumination, and can be applied to a target region requiring a large range of illumination. The total reflection lens 300 of the prior art has a wide-necked and narrow-conical light-transmissive body, and a continuous through-hole 310 is disposed along the central axis C ₂ , and an outer taper hole 320 is connected to the upper end of the through-hole 310. The through hole 310 is provided as a light incident mirror surface, and the outer taper hole 320 is provided as a light exit mirror surface. One or more plurality of grooving grooves 321 may be formed at the outer taper hole 320 to provide the light source 200 at the through hole 310 of the total reflection lens 300. The light source 200 may be unshielded from the central through hole 310 and outside. In addition to expanding the light distribution angle at the taper hole 320, the ring side light around the light source 200 can be redirected to the outer taper hole 320 by the refraction of the entrance mirror 330 and the cone 330 outside the total reflection lens. In order to achieve the illuminating effect, the illuminating intensity and the symmetry of the illuminating light with the increased illumination area, the total reflection lens can also provide the light to be projected from the grooving 321 so that it has the function of guiding the light side view. .

However, when the above-mentioned total reflection lens 100 or 300 is used with a lamp cover of a special specification, such as the lamp cover 200A having the ink-jet engraving shown in FIG. 3, the light guided by the total reflection lens 100 of FIG. 1 is excessively concentrated. The light guided by the total reflection lens 300 of FIGS. 2A and 2B is too diffuse in the direction of emission, and it is difficult to cooperate with such a lamp cover to produce a better illuminating effect. In order to illuminate with such a lampshade, it is necessary to design a lens of a special specification in order to reduce unnecessary light source loss and enhance illumination, and the user can also feel the artistic effect exerted by the lampshade.

An object of the present invention is to provide a total reflection lens capable of providing two independent light paths, which are different from the total reflection surface and the exit surface, and the illumination angle can be matched with a special size lampshade to enhance illumination and reduce unnecessary light source. loss.

In order to achieve the above object, a total reflection lens provided by the present invention comprises a light transmitting body and has an axis of symmetry. The light-transmitting body includes an annular protrusion surrounding the axis of symmetry, and has a first recess and a second recess arranged on the axis of symmetry. The first recessed hole is located below the second recessed hole, has a first opening facing downward for receiving a light source, and has an inner top surface opposite to the first opening, and an inner side wall connected to the first opening and the inner side Between the faces. The second recess has an upwardly facing second opening and an inner side connecting the second opening. The surface of the light transmissive body includes: a first light incident surface is located on an inner sidewall of the first recessed hole to guide light from the light source into a first light path; and a second light incident surface is located inside the first recessed hole The top surface is connected to the first light incident surface, wherein the second light incident surface is a convex downward curved surface to guide the light from the light source into a second light path; and the external total reflection surface is located outside the first concave hole Connecting a lower edge of the annular projection and located on the first light path for reflecting light from the first light incident surface in the light transmissive body; an inner total reflection surface is located on the inner side of the second recess, and external The total reflection surface is opposite to the second light path for reflecting the light from the second light incident surface in the light transmitting body; the first exit surface is a surface of the annular convex portion and is located on the external total reflection surface a first light path between the internal total reflection surface for guiding light from the external total reflection surface to a first exit direction; and a second exit surface coupled to the internal total reflection surface and the first exit surface Between the second light path for the future Total internal reflection light is guided to a second surface of the outgoing direction.

In one embodiment, the light transmissive body includes an upper narrow upper and lower upper cone located above the annular convex portion, and an upper wide and narrow lower lower cone is located below the annular convex portion, wherein the first concave hole is a A cylindrical recessed hole, the second recessed hole being an inverted conical recessed hole. In this case, the internal total reflection surface may be a convex surface convex toward the inside of the inverted conical recess, the external total reflection surface is a convex surface convex toward the outside of the transparent body, and the first exit surface is a convex surface convex toward the outside of the transparent body. And the second exit surface is a concave surface that is concave toward the inside of the light-transmitting body.

In an embodiment, the angle between the internal total reflection surface and the second exit surface is between 50 and 54 degrees. The first exit mask has a first width, and the second exit mask has a second width, the ratio of the first width to the second width being between 1 and 1.1. The internal total reflection surface has a slope of 2 and the external total reflection surface has a slope of 1.67. The slope of the first exit surface is 0.19.

In an embodiment, the angle between the first exit direction and the axis of symmetry is between 10 and 30 degrees. Moreover, the angle between the second exit direction and the axis of symmetry is also between 10 and 30 degrees.

In one embodiment, the light transmissive body has a material refractive index of 1.49 and a total reflection critical angle of 42 degrees.

The invention modifies the overall shape of the lens, and designs an annular projection and two cones above and below, and two recessed holes in the two cones, providing two main totally reflected light paths, and the light is The angle between the exit direction and the direction of the symmetry axis converges to within 10 to 30 degrees and is evenly distributed, which can guide the light to a specific illumination area, thereby effectively improving the illumination brightness and the chromaticity of the light in a small area. Therefore, it is different from the traditional lens structure and the illumination effect it can provide.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments. The directional terms mentioned in the following embodiments, such as upper, lower, left, right, front or rear, etc., are only used to refer to the directions of the accompanying drawings. Therefore, the directional terms are used for illustration only and are not intended to limit the invention.

Please refer to FIG. 4, which is a total reflection lens according to a first embodiment of the present invention. The total reflection lens 400 includes a light transmissive body 410. The light-transmitting body 410 has an axis of symmetry C, and its outer shape includes an annular protrusion 411 surrounding the axis of symmetry C, and has a first recessed hole 420 and a second recessed hole 430 arranged along the axis of symmetry C. The first recessed hole 420 is open downward to accommodate a light source 200. The second recessed hole 430 has an opening facing upward and is located above the first recessed hole 420.

It is worth mentioning that the transparent body 410 is divided into a first light incident surface 421, a second light incident surface 422, an external total reflection surface 412, and an internal total reflection surface 432 by its outer shape structure. A first exit surface 413 and a second exit surface 414. The first light incident surface 421, the outer total reflection surface 412, and the first exit surface 413 constitute a first light path L ₁ . The second light incident surface 422, the inner total reflection surface 432, and the second exit surface 414 constitute a second light path L ₂ . Therefore, the total reflection lens 400 of the present invention can provide two independent light paths, which are different from the total reflection surface and the exit surface, wherein the light is refracted on both the light incident surface and the exit surface.

The first light incident surface 421 is an inner sidewall of the first recess 420 for guiding light from the light source 200 into a first light path L ₁ ; the outer total reflection surface 412 is an outer surface of the lower half of the light transmitting body 410 . Connecting the lower edge of the annular projection 411 and located on the first optical path L ₁ for totally reflecting the light from the first light incident surface 421; the first exit surface 413 is the surface of the annular projection 411, located outside The first light path L ₁ between the total reflection surface 412 and the internal total reflection surface 432 is used to guide the light from the external total reflection surface 412 to a first emission direction D ₁ . The angle β between the first exit direction D ₁ and the axis of symmetry C is between 10 and 30 degrees.

The second light incident surface 422 is a convex downward curved surface located on the inner top surface of the first recessed hole 420 and connected to the first light incident surface 421 for guiding the light from the light source 200 into a second light path L _{2 .} The inner total reflection surface 432 is an inner side surface of the second recessed hole 430, opposite to the outer total reflection surface 412, on the second light path L ₂ for totally reflecting the light from the second light incident surface 422; the second exit The surface 414 is connected between the internal total reflection surface 432 and the first exit surface 413 and is located on the second light path L ₂ for guiding the light from the internal total reflection surface 432 to a second emission direction D ₂ . The angle γ between the second exit direction D ₂ and the axis of symmetry C is between 10 and 30 degrees.

In one embodiment, the light transmissive body 410 has a material refractive index of 1.49 and a total reflection critical angle of 42 degrees. By exemplifying the bevel design method of the transparent body 410: first, the slope of the internal total reflection surface 432 is set to 2, and then the angle λ between the internal total reflection surface 432 and the second exit surface 414 is adjusted to be between 50 and 54 degrees. . The slope of the external total reflection surface 412 was set to 1.67, and the slope of the first exit surface 413 was adjusted to be 0.19. In one embodiment, the first exit surface 413 has a first width W ₁ that is the distance between the intersection E of the first exit surface 413 and the second exit surface 414 to the outer edge E ₁ of the first exit surface 413. Second exit surface 414 has a second width W _2, as the distance between the first emission surface 413 and the second exit surface 414 of the cross line E to the second exit surface 414 and the line of intersection of the total internal reflection surface 432 of the E _2. The ratio of the width W _{2 of the} first width W ₁ to the second exit surface 414 may be between 1 and 1.1.

4A illustrates a method of designing a surface tangent slope of a total reflection lens according to an embodiment of the present invention, such as a curved surface design for a second light incident surface 422 or a total reflection lens shown in FIG. The refracting surface shown in FIG. 4A is a curved surface, and the ray is incident on the P ₂ point on the curved surface by the light source position P ₁ in the incident direction I before the refracting, and the refracted exiting the refracting surface in the outgoing direction O. The tangential direction T tangent to the refracting surface at point P ₂ is the normal direction N perpendicular to the tangential direction T. The incident direction I has an angle θ with the normal direction N; the exit direction O has an angle θ' with the normal direction N. The incident direction I has an angle α with the optical axis, and the horizontal axis H is perpendicular to the optical axis and has an angle θ _T with the tangential direction T. The exit direction O has an angle θ _P with the horizontal axis H. Designed with the following operations:

Bring the above two types into Snell's law, Where n _air is the refractive index of the air and n' is the refractive index of the material of the light transmitting body 410, so that:

Then calculate the slope of the surface tangent.

5A to 5D are a total reflection lens 400a according to a second embodiment of the present invention. According to the above structural features and design methods, the slope of the first exit surface 413a and the shape of the annular projection 411a are adjusted such that the overall appearance of the total reflection lens 400a is different from that of the previous embodiment. 5A is a perspective view of the total reflection lens 400a; FIG. 5B is a plan view of FIG. 5A; FIG. 5C is a side view of FIG. 5A, and FIG. 5D is a bottom view of FIG. Fig. 5A shows the three-dimensional structure of the annular projection 411a. The outer reflection lens 400a has an outer shape formed by an annular projection 411a, an upper cone 440a located above the annular projection 411a, and a lower cone 450b located below the annular projection 411a. The upper cone 440a is a structure that is narrow and wide, and has an inverted conical recess 430a inside. The opening of the inverted conical recess 430a is the top of the upper cone 440a. The lower cone 450b is an upper wide and narrower structure having a cylindrical recessed hole 420a therein. The opening of the cylindrical recess 420a is the bottom of the lower cone 450a.

Fig. 6 shows a total reflection lens 400b according to a third embodiment of the present invention. The outer surface of the total reflection lens 400b is mainly curved, and the side view of the overall shape is similar to the shape of a bat. The first recessed hole 420b is also a cylindrical recessed hole, and the second recessed hole 430b is also an inverted conical recessed hole 430b. However, in the inverted conical recessed hole, the internal total reflection surface 432b is an inclined convex surface which is convex toward the inside of the inverted conical recessed hole 430b and which is convex toward the inverted conical recessed hole 430b. The external total reflection surface 412b is a convex surface convex toward the outside of the light-transmitting body 410b, and the first exit surface 413b is a convex surface convex toward the outside of the light-transmitting body 410b or convex toward the outside of the annular convex portion 411b, that is, outside the lower cone The surface, and the second exit surface 414b is a concave surface that is recessed toward the interior of the light-transmissive body 410b.

Figure 7 is a perspective view of an embodiment of the present invention in which a total reflection lens 400 of the present invention is applied to a lamp cover 200A having an ink-jet engraving as shown in Figure 3. The effect is that the angle β between the first exit direction D ₁ and the axis of symmetry C is between 10 and 30 degrees. The angle γ between the second exit direction D ₂ and the axis of symmetry C is between 10 and 30 degrees.

The present invention utilizes the principle of a total reflection lens, but the direction of illumination is not concentrated. The illuminating angles β and γ of the present invention are located between ±10 degrees and ±30 degrees. In order to reduce the light-emitting area, the present invention modifies the overall shape of the lens, and designs an annular projection and two cones above and below, and two recessed holes in the two cones, providing two main full Reflecting the light path, guiding the light to the fixed illumination area, effectively improving the brightness and chromaticity of the small area. Therefore, it is different from the structure of the conventional total reflection lens and the illumination effect it can provide.

Based on the structural features described in the embodiments of the present invention, the total reflection lens of the present invention is suitable for use with a lampshade of a particular specification. Moreover, the lens designer can more conveniently adjust the lens shape and the illumination angle according to the appearance of the lampshade to be matched, and unnecessary light source loss can be reduced without greatly changing the lens structure. Compared to conventional total reflection lenses, users can get brighter visual effects at the same power.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent. In addition, any of the objects or advantages or features of the present invention are not required to be achieved by any embodiment or application of the invention. In addition, the abstract sections and headings are only used to assist in the search of patent documents and are not intended to limit the scope of the invention.

100‧‧‧Traditional total reflection lens
110‧‧‧ recessed hole
112‧‧‧ protruding top
114‧‧‧ inside side wall
120‧‧‧ total reflection surface
130‧‧‧Glossy
C ₁ ‧‧‧ center axis
200‧‧‧Light source
200A‧‧‧shade with ink-carved
300‧‧‧Generally known total reflection lens
C ₂ ‧‧‧ central axis
310‧‧‧through holes
320‧‧‧Extended taper
321‧‧‧"
330‧‧‧ outer cone
400‧‧‧ total reflection lens
C‧‧‧Axis axis
410‧‧‧Lighting body
411‧‧‧ annular projection
420‧‧‧ first recess
430‧‧‧ second recess
421‧‧‧ first light surface
422‧‧‧Second entrance
412‧‧‧External total reflection surface
432‧‧‧Internal total reflection surface
413‧‧‧First exit surface
414‧‧‧second exit surface
W ₁ ‧‧‧first width of the first exit surface
W ₂ ‧‧‧second width of the second exit surface
E‧‧‧The intersection of the first exit surface and the second exit surface
E ₁ ‧‧‧Outer edge of the first exit face
E ₂ ‧‧‧The intersection of the second exit surface and the internal total reflection surface
L ₁ ‧‧‧First light path
L ₂ ‧‧‧second light path
D ₁ ‧‧‧first exit direction
D ₂ ‧‧‧Second direction of exit λ‧‧‧An angle between the total total reflection surface and the second exit surface β‧‧‧An angle between the first exit direction and the axis of symmetry γ‧‧‧An angle between the second exit direction and the axis of symmetry
P ₁ ‧‧‧Light source location
P ₂ ‧‧‧ Refraction points on the surface
I‧‧‧Injection direction
O‧‧‧Directing direction
T‧‧‧ Tangential direction of the refractive surface
N‧‧‧ normal direction of the refractive surface
H‧‧‧Horizontal axis θ‧‧‧An angle between the incident direction and the normal direction of the refractive surface θ'‧‧‧An angle between the exit direction and the normal direction of the refractive surface α‧‧‧An angle between the incident direction and the optical axis θ _T ‧‧‧An angle between the horizontal axis and the tangential direction θ _P ‧‧‧An angle between the exit direction and the horizontal axis
n'‧‧‧Refractive index of total reflection lens
400a‧‧‧ total reflection lens
413a‧‧‧First exit surface
411a‧‧‧ annular projection
420a‧‧‧ cylindrical recess
430a‧‧‧ inverted conical recess
440a‧‧‧Upper cone
450b‧‧‧ Lower cone
400b‧‧‧ total reflection lens
410b‧‧‧Lighting body
411b‧‧‧ annular projection
412b‧‧‧External total reflection surface
413b‧‧‧first exit surface
414b‧‧‧second exit surface
420b‧‧‧ first recess
430b‧‧‧Second recessed hole (inverted conical recessed hole)
432b‧‧‧Internal total reflection surface

FIG. 1 is a schematic view showing the structure of a conventional total reflection lens.

2A and 2B are schematic views showing another conventional total reflection lens structure and a light path.

Figure 3 is a schematic view of a lampshade having ink-like engraving.

4 is a schematic structural view of a total reflection lens according to a first embodiment of the present invention.

4A is a schematic view showing a design method of a total reflection lens into a curved surface according to an embodiment of the present invention.

FIG. 5A is a perspective view showing the three-dimensional structure of a total reflection lens according to a second embodiment of the present invention.

5B to 5D are a plan view, a side view, and a bottom view of a total reflection lens according to a second embodiment of the present invention.

Figure 6 is a schematic view showing the structure of a total reflection lens according to a third embodiment of the present invention.

FIG. 7 is a schematic diagram of an illumination angle of a total reflection lens applied to a lamp according to an embodiment of the present invention.

no

no

200‧‧‧Light source

400‧‧‧ total reflection lens

C‧‧‧Axis axis

410‧‧‧Lighting body

411‧‧‧ annular projection

412‧‧‧External total reflection surface

413‧‧‧First exit surface

414‧‧‧second exit surface

420‧‧‧ first recess

421‧‧‧ first light surface

422‧‧‧Second entrance

430‧‧‧ second recess

432‧‧‧Internal total reflection surface

L ₁ ‧‧‧First light path

L ₂ ‧‧‧second light path

D ₁ ‧‧‧first exit direction

D ₂ ‧‧‧second exit direction

λ‧‧‧An angle between the internal total reflection surface and the second exit surface

β‧‧‧The angle between the first exit direction and the axis of symmetry

γ‧‧‧An angle between the second exit direction and the axis of symmetry

W ₁ ‧‧‧first width of the first exit surface

W ₂ ‧‧‧second width of the second exit surface

E‧‧‧The intersection of the first exit surface and the second exit surface

E ₁ ‧‧‧Outer edge of the first exit face

E ₂ ‧‧‧The intersection of the second exit surface and the internal total reflection surface

Claims (10)

A total reflection lens includes: a light transmitting body having an axis of symmetry, the light transmitting body including an annular protrusion surrounding the axis of symmetry, and having a first recessed hole and a second recessed hole arranged on the axis of symmetry The first recessed hole is located below the second recessed hole, and has a first opening facing downward for receiving a light source, and has an inner top surface opposite to the first opening, and an inner side wall is connected thereto Between the first opening and the inner top surface, the second recess has an upwardly facing second opening and an inner side connecting the second opening, wherein the surface of the transparent body comprises: a first light incident surface, The inner side wall of the first recessed hole is configured to guide light from the light source into a first light path; a second light incident surface is located on the inner top surface of the first recessed hole and connects the first light incident surface a surface, wherein the second light incident surface is a convex downward curved surface to guide light from the light source into a second light path; an external total reflection surface located outside the first concave hole, connecting the annular convex The lower edge of the outlet and located on the first light path The light from the first light incident surface is reflected in the light transmissive body; an inner total reflection surface is located on the inner side surface of the second recessed hole, opposite to the outer total reflection surface, and located in the second light a path for reflecting light from the second light incident surface in the light transmissive body; a first exit surface being a surface of the annular projection and located at the outer total reflection surface and the internal total reflection The first light path between the faces is for guiding light from the external total reflection surface to a first exit direction; and a second exit surface is connected to the inner total reflection surface and the first exit surface Between the two light paths, the light from the internal total reflection surface is guided to a second exit direction. The total reflection lens of claim 1, wherein the light-transmissive body comprises an upper narrow upper and lower upper cone located above the annular convex portion, and an upper wide and narrow lower lower cone is located in the annular shape Below the projection, wherein the first recess is a cylindrical recess and the second recess is an inverted conical recess. The total reflection lens of claim 2, wherein the internal total reflection surface is a convex surface that protrudes toward the inside of the inverted conical recess and protrudes toward the second opening, and the external total reflection surface is a convex surface. a convex surface on the outside of the light-transmitting body, the first exit surface is a convex surface convex toward the outside of the light-transmitting body, and the second exit surface is a concave surface concave toward the inside of the light-transmitting body. The total reflection lens of claim 2, wherein the angle between the internal total reflection surface and the second exit surface is between 50 and 54 degrees. The total reflection lens of claim 4, wherein the first exit mask has a first width, the second exit mask has a second width, and a ratio of the first width to the second width is Between 1 and 1.1. The total reflection lens of claim 5, wherein the internal total reflection surface has a slope of 2, and the external total reflection surface has a slope of 1.67. The total reflection lens of claim 6, wherein the first exit surface has a slope of 0.19. The total reflection lens of claim 1, wherein the first exit direction and the axis of symmetry are between 10 and 30 degrees. The total reflection lens of claim 1, wherein an angle between the second exit direction and the axis of symmetry is between 10 and 30 degrees. The total reflection lens of claim 1, wherein the transparent body has a material refractive index of 1.49 and a total reflection critical angle of 42 degrees.