CN104296066A - Lens and its light source module - Google Patents

Abstract

The invention relates to a lens which is used for adjusting light rays emitted by a light source, and comprises a first lens, a second lens and a third lens, wherein the third lens covers the second lens, the second lens covers the first lens, the second lens and the third lens are sequentially overlapped, the refractive index of the third lens is smaller than that of the second lens, the refractive index of the second lens is smaller than that of the first lens, and the light rays emitted by the light source finally exit to the outside of the lens after sequentially passing through the first lens, the second lens and the third lens, so that the light rays emitted into the lenses can be better deflected to the side parts of the lenses, the forward light intensity is reduced, the lateral light intensity is enhanced, and the light-exiting angle is enlarged. The invention also relates to a light source module comprising the lens.

Description

Lens and its light source module

technical field

The invention relates to the field of optics, in particular to a lens and a light source module thereof.

Background technique

The effect of lamps using traditional light sources can basically meet the needs of various aspects, but the energy consumption is too large. Therefore, as a new generation of light sources, LEDs (Light Emitting Diode) have a tendency to gradually replace traditional light sources. The light source of the backlight module of the existing display is gradually replaced by light emitting diodes.

Existing display backlight modules are usually direct-lit light sources. The advantage of the direct light source lies in the use of the lens, so a small amount of light-emitting diodes can meet the demand. That is, the first optical adjustment is made to the light of the light-emitting diode through the lens to form a relatively divergent light, and then it is injected into the diffusion plate for further diffusion, so as to obtain a more uniform outgoing light. However, the optical adjustment capability of the existing lenses is still insufficient. Therefore, how to design a lens that can make the light emitted by the light-emitting diodes diverge better to both sides has been a subject that the industry has been exploring.

Contents of the invention

In view of this, it is necessary to provide a lens and a light source module thereof that can better diverge the light emitted by the LED.

A lens, which is used to adjust the light emitted by a light source, the lens includes a first lens, a second lens and a third lens, the third lens covers the second lens, the second lens covers the first lens, the first lens , the second lens and the third lens are sequentially stacked, the refractive index of the third lens is smaller than the refractive index of the second lens, the refractive index of the second lens is smaller than the refractive index of the first lens, the light emitted by the light source passes through the first lens, The second lens and the third lens finally emerge outside the lens.

A light source module includes a light source and the above-mentioned lens.

Since the lens of the embodiment of the present invention uses three lenses with different refractive indices, when light enters a lens with a lower refractive index from a layer with a higher refractive index, the light is deflected, so that the light can be better directed toward the lens. The side deflection reduces the forward light intensity, enhances the side light intensity and expands the light angle.

Description of drawings

FIG. 1 is a schematic perspective view of a lens provided by an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the lens in FIG. 1 .

FIG. 3 is a sectional view of the lens along III-III in FIG. 1 and a sectional view of a light source module composed of a light source.

Description of main component symbols

Light source module 100 lens 10 first lens 11 first incident surface 111 first light emitting surface 112 second lens 12 Second incident surface 121 second light emitting surface 122 concave 1221 curved surface 1222 bottom surface 123 side 124, 133 third lens 13 third incident surface 131 third light emitting surface 132 light source 20

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

Detailed ways

Please refer to FIG. 1 and FIG. 2 , the lens 10 provided by the embodiment of the present invention includes three lenses, and the refractive indices of the three lenses are different. In this embodiment, the three lenses are the first lens 11, the second lens 12 and the third lens 13, wherein the first lens 11 is located at the innermost layer of the lens 10, and the third lens 13 is located at the outermost layer of the lens 10 , the second lens 12 is located between the first lens 11 and the third lens 13 , that is, the third lens 13 covers the second lens 12 , and the second lens 12 covers the first lens 11 .

Please also refer to FIG. 3 , the lens 10 is in the shape of a cylinder as a whole. The first lens 11 includes a first light incident surface 111 and a first light exit surface 112 . The first light incident surface 111 is a plane, and the first light exit surface 112 is a curved surface. The curved surface protrudes upward from the first light incident surface 111 to form an upwardly convex smooth curved surface. The central axis of the first light emitting surface 112 coincides with the central axis of the lens 10 . The slope of the section of the first light-emitting surface 112 gradually decreases from the bottom of the first light-incident surface 111 to the top of the lens 10 , and is smoothly connected at the top.

The second lens 12 is disposed on the first lens 11 . The second lens 12 includes a second light incident surface 121 , a second light exit surface 122 , a bottom surface 123 and a side surface 124 .

The second light incident surface 121 is recessed from the bottom surface 123 toward the inside of the lens 10 . The second light incident surface 121 is a curved surface, and the shape of the curved surface is the same as that of the first light exit surface 112 of the first lens 11, so that the second light incident surface 121 of the second lens 12 is the same as the first light incident surface 112 of the first lens 11. The light-emitting surface 112 is completely bonded to completely cover the second lens 12 on the first lens 11 . In this embodiment, the outline of the second light incident surface 121 is roughly an ellipsoid, the short axis of which is located on the plane where the bottom surface 123 is located, and the long axis is perpendicular to the bottom surface 123 . After the light is incident on the first lens 11 from the first light incident surface 111, it is refracted by the first light exit surface 112, and the light diverges towards both sides of the first lens 11, and due to the curved shape of the first light exit surface 112, Thus more light is deflected towards the side.

The second light emitting surface 122 is disposed above the second light incident surface 121 . The second light emitting surface 122 is an aspheric surface, which includes a concave surface 1221 at the center of the top and an arc surface 1222 on the periphery of the concave surface 1221 . The concave surface 1221 is located at the center of the lens 10 and is facing the second light-incident surface 121 and is recessed toward the second light-incident surface 121 . The concave surface 1221 may be a concave arc surface, etc., for diverging the forward light reaching the concave surface 1221 . The arc surface 1222 is a curved surface protruding outward in a direction away from the light source 20 , and the arc surface 1222 is smoothly connected with the concave surface 1221 .

The bottom surface 123 is coplanar with the first light incident surface 111 of the first lens 11 , so that when the second lens 12 covers the first lens 11 , the bottoms of the two form a plane.

The side surface 124 extends from the bottom surface 123 toward a direction parallel to the optical axis of the lens 10 . The side surface 124 extends vertically upward along the optical axis and intersects with the second light-emitting surface 122 to form an edge of the second light-emitting surface 122 . The side surface 124 is cylindrical, and its center is located on the optical axis of the lens 10 . The projection of the side surface 124 on the plane where the bottom surface 123 is located is a circle.

The third lens 13 includes a third light incident surface 131 , a third light exit surface 132 and a side surface 133 . The third light incident surface 131 is an aspheric surface, and its curved shape is the same as that of the second light exit surface 122 of the second lens 12, so that the third light incident surface 131 of the third lens 13 can be completely attached to the surface of the second lens 12. on the second light-emitting surface 122 . The third light emitting surface 132 is a plane, which is perpendicular to the optical axis of the lens 10 . The side surface 133 connects the third light incident surface 131 and the third light exit surface 132 . The side surface 133 extends from the third light incident surface 131 toward a direction parallel to the optical axis of the lens 10 and intersects with the third light exit surface 132 . The side surface 133 is cylindrical, and its center is located on the optical axis of the lens 10 . The projection of the side surface 133 on the plane where the third light emitting surface 132 is located is a circle.

The first lens 11, the second lens 12 and the third lens 13 are stacked sequentially, the first light-emitting surface 112 of the first lens 11 is bonded to the second light-incident surface 121 of the second lens 12, and the second light-emitting surface 121 of the second lens 12 The light emitting surface 122 is bonded to the third light incident surface 131 of the third lens 13 , so that the combined lens 10 has a cylindrical shape. Wherein, the first light incident surface 111 of the first lens 11 and the bottom surface 123 of the second lens 12 form a plane, which is parallel to the third light exit surface 132 of the third lens 13 . The first lens 11, the second lens 12 and the third lens 13 are made of different materials respectively, wherein the refractive index of the material of the first lens 11 is greater than the refractive index of the material of the second lens 12, and the refractive index of the material of the second lens 12 The refractive index is greater than that of the material of the third lens 13 . In this embodiment, the first lens 11 adopts optical-grade glass material lead glass (ZF6), the second lens 12 adopts polydimethylsiloxane (polydimethylsiloxane, PDMS), and the third lens 13 adopts polymethyl methacrylate (polymethylmethacrylate, PMMA). The polydimethylsiloxane used in the second lens 12 has good adhesiveness, and can better combine the first lens 11 and the third lens 13 .

The light source 20 is disposed below the lens 10 to form a light source module 100 . Further, the light source 20 is a light emitting diode, and the light emitting surface of the light emitting diode is attached to the first light incident surface 111 of the first lens 11 . The light emitted by the light source 20 directly enters the lens 10, first enters the first lens 11, and when entering the second lens 12 from the first lens 11, since the refractive index of the first lens 11 is greater than that of the second lens 12, the light Towards the lateral deflection of the lens 10; when light enters the third lens 13 from the second lens 12, since the refractive index of the second lens 12 is greater than the refractive index of the third lens 13, the light is further deflected toward the lateral direction of the lens 10, Reduce the front light intensity, increase the side light intensity and expand the light angle.

It can be understood that, for those skilled in the art, various other corresponding changes and deformations can be made according to the technical concept of the present invention, and all these changes and deformations should belong to the protection scope of the claims of the present invention .

Claims (10)

1. A lens, which is used to adjust the light emitted by the light source, is characterized in that: the lens includes a first lens, a second lens and a third lens, the third lens covers the second lens, and the second lens covers the second lens One lens, the first lens, the second lens and the third lens are stacked in sequence, the refractive index of the third lens is smaller than the refractive index of the second lens, the refractive index of the second lens is smaller than the refractive index of the first lens, the light emitted by the light source After passing through the first lens, the second lens and the third lens in sequence, it finally exits the lens. 2. The lens according to claim 1, wherein the first lens comprises a first light incident surface and a first light exit surface, the second lens comprises a second light incident surface and a second light exit surface, and the first light exit surface The surface and the second light incident surface are both curved surfaces and have the same shape, and the second light incident surface is bonded to the first light exit surface. 3. The lens according to claim 2, wherein the third lens comprises a third light incident surface and a third light exit surface, the second light exit surface of the second lens and the third light incident surface of the third lens They are all curved surfaces and have the same shape, and the third light-incident surface and the second light-exit surface are bonded and connected. 4. The lens according to claim 2, wherein the second light-emitting surface of the second lens includes a concave surface at the center of the top and an arc surface on the periphery of the concave surface, the concave surface is concave toward the direction of the second light-incident surface, The arc surface protrudes outward in a direction away from the second light incident surface. 5. The lens according to claim 4, wherein the second lens further comprises a bottom surface and a side surface, the bottom surface and the first light incident surface of the first lens are flat and coplanar, and the side surface is on the bottom surface The projection of is a circle. 6. The lens according to claim 5, wherein the third lens comprises a third light incident surface and a third light exit surface, the third light incident surface is attached to the second light exit surface of the second lens, and the third light incident surface is bonded to the second light exit surface of the second lens. The three light exit surfaces are a plane parallel to the first light incident surface of the first lens. 7. The lens according to claim 6, wherein the third lens further comprises a side surface, the side surface is connected to the third light incident surface and the third light exit surface, and the projection of the side surface on the third light exit surface is a round. 8. The lens according to claim 1, wherein the first lens is made of optical-grade glass material lead glass, the second lens is made of polydimethylsiloxane, and the third lens is made of polymethacrylic acid Methyl ester manufacture. 9. A light source module, comprising a light source and the lens according to any one of claims 1-8. 10. The light source module according to claim 9, wherein the light source is a light emitting diode, and the light emitting surface of the light emitting diode is attached to the first light incident surface of the first lens.