TWI448760B - Camera module - Google Patents

Description

Lens module

The invention relates to a lens module.

With the development of multimedia technology, electronic products with camera functions are increasingly favored by consumers. While people are pursuing miniaturization of electronic products, they have put forward higher requirements for the image quality of the objects they shoot. The image of the subject is clear. The quality of imaging depends to a large extent on the pros and cons of the lens module in the electronic product.

As shown in FIG. 1, most lens modules include a lens barrel 80 and a plurality of lenses 81 housed in the lens barrel 80. One end of the lens barrel 80 is provided with a light entrance hole 84. Each lens 81 includes an optical portion 811 facing the light entrance aperture 84 and a non-optical portion 813 surrounding the optical portion 811. The non-optical portion 813 is adhered to the inner surface of the lens barrel 80 by a colloid for supporting the corresponding optical portion 811. The outer surface of the non-optical portion 813 is a flat surface. During shooting, the optical image signal entering the lens barrel 80 from the light entrance hole 84 is focused by the lens 81 and reaches the image sensor located on the side of the lens module. The image sensor converts the optical image signal into an electronic image signal for imaging. As shown in the optical path I in FIG. 1 , since the outer surface of the non-optical portion 813 is a flat surface, a part of the light entering the lens barrel 80 during shooting may be totally reflected in the non-optical portion 813 when passing through the lens 81, resulting in multiple total reflections. The edge of the lens 81 forms stray light and is projected onto the image sensor, thereby affecting the shooting effect.

In view of this, it is necessary to provide a lens module that can eliminate stray light.

A lens module includes a lens barrel and at least one lens received in the lens barrel, the lens is fixed on an inner surface of the lens barrel, and the lens includes an optical portion and a non-optical portion surrounding the optical portion. The outer surface of the non-optical portion of the lens is provided with a plurality of tiny densely arranged protrusions for changing a direction of illumination of a portion of the light incident on the outer surface of the non-optical portion when the light penetrates the lens, such that Part of the light can exit the lens and exit outward.

Compared with the prior art, the outer surface of the non-optical portion of the lens of the lens module provided by the present invention is provided with a plurality of protrusions, and the protrusions change a part of the light that is incident on the outer surface of the non-optical portion when the light penetrates the lens. The illumination direction allows the light to pass through the lens and exit outward, thereby reducing stray light in the edge region of the lens and improving the imaging quality of the lens module.

10‧‧‧Mirror tube

11‧‧‧Cylinder

112‧‧‧ inner surface

12‧‧‧ front cover

120‧‧‧Into the light hole

20‧‧‧ lens group

20a‧‧‧first lens

20b, 30b‧‧‧ second lens

20c, 40c‧‧‧ third lens

22‧‧‧Optical Department

221‧‧‧Into the glossy surface

222, 322‧‧‧ glazing

24, 34, 44‧‧‧ Non-optical department

2411, 341, 441‧‧ ‧ end faces

242, 342, 442‧‧‧ like end face

243, 343, 443‧‧‧ outside

244‧‧‧First slope

245‧‧‧second slope

246, 346, 446‧‧

Θ‧‧‧ angle

80‧‧‧Mirror tube

81‧‧‧ lens

84‧‧‧Into the light hole

811‧‧‧Optical Department

813‧‧‧Non-optics

FIG. 1 is a schematic structural view of a lens module of the prior art.

2 is a schematic structural view of a lens module according to a first embodiment of the present invention.

Figure 3 is an enlarged schematic view of the portion of the circle III of Figure 2.

4 is a schematic structural view of a lens module according to a second embodiment of the present invention.

FIG. 5 is a schematic structural view of a lens module according to a third embodiment of the present invention.

The present invention will be further described below in conjunction with the embodiments with reference to the accompanying drawings.

Please refer to FIG. 2 , which is a lens module according to a first embodiment of the present invention. The lens module includes a lens barrel 10, a lens group 20 received in the lens barrel 10, and An image sensor (not shown) on one side of the lens group 20. The lens group 20 includes a first lens 20a, a second lens 20b and a third lens 20c which are sequentially received in the lens barrel 10.

The lens barrel 10 is a semi-closed cylindrical body. The lens barrel 10 includes an annular cylinder 11 and a front cover 12. The front cover 12 is formed at one end of the cylindrical body 11 close to the object to be photographed, and the cylindrical body 11 is integrally formed with the front cover 12. In the specific implementation, the front cover 12 may be separately formed separately from the tubular body 11 , and the front cover 12 is covered on the cylindrical body 11 during assembly. An entrance hole 120 is defined in the center of the front cover 12, and external light enters the lens barrel 10 through the light entrance hole 120. The barrel 11 includes an inner surface 112 that surrounds the periphery of the lens group. The inner surface of the cylinder 11 is black, which absorbs light projected onto the inner surface 112 of the cylinder 11 to reduce the influence of stray light formed by the light irradiated onto the inner surface 112 of the cylinder 11 on the image quality. .

The first, second, and third lenses 20a, 20b, and 20c are each made of glass or plastic. Each of the lenses 20a, 20b, 20c includes an intermediate optical portion 22 and a non-optical portion 24 that surrounds and surrounds the optical portion 22. The optical portion 22 is an optically active portion of each of the lenses 20a, 20b, and 20c. The optical portion 22 includes a light incident surface 221 facing the light entrance hole 120 and an opposite light exit surface 222. The 221 and the light exiting surface 222 may be arranged in a concave or convex shape as needed to diverge or converge the light. The optical portion 22 is a spherical lens or an aspheric lens. The light exit surface 222 of the optical portion 22 of the second lens 20b is a convex surface. The non-optical portion 24 of the second lens 20b surrounds and connects the optical portion 22. The non-optical portion 24 is substantially in the shape of a circular plate, and includes an object end surface 241 that radiates outwardly from a periphery of the light incident surface 221, and an image end surface 242 that radiates outward from a periphery of the light exit surface 222. An outer side surface 243 between the object end surface 241 and the outer peripheral edge of the image end surface 242 is joined. The non-optical portion 24 The outer side surface 243 is directly adhered to the inner surface 112 of the lens barrel 10, and the non-optical portion 24 mainly functions to position and support the optical portion 22. The object end surface 241, the image end surface 242 and the outer surface 243 of the non-optical portion 24 of the first and third lenses 20a, 20c, and the object end surface 241 and the image end surface 242 of the second lens 20b are both planar.

A plurality of minutely densely arranged projections 246 are formed on the outer side surface 243 of the non-optical portion 24 of the second lens 20b. As shown in FIG. 3, each of the protrusions 246 has a "V" shape in cross section and includes a first slope 244 and a second slope 245. The first inclined surface 244 and the second inclined surface 245 are inclined from the outer side surface 243 of the second lens 20b toward the inner surface 112 of the lens barrel 10 and extend close to each other, and intersect at an end close to the inner surface 112 of the lens barrel 10, respectively. An angle θ is formed. In various embodiments, the angle θ between the first bevel 244 and the second bevel 245 of each protrusion 246 may vary between 1° and 179°. The first and second slopes 244 and 245 are all flat. The protrusions 246 are continuously arranged in the axial direction of the lens barrel 10. The first slopes 244 of the protrusions 246 are parallel to each other, wherein the first slopes 244 of the protrusions 246 located near the object end surface 241 of the two outermost protrusions 246 extend obliquely from the outer circumference of the object end surface 241 toward the direction of the image end surface 242. The first inclined surface 244 and the object end surface 241 have an obtuse angle. The second slopes 245 of the protrusions 246 are parallel to each other, and the second slopes 245 of the protrusions 246 located near the image end surface 242 in the outermost two protrusions 246 extend obliquely from the outer circumference of the image end surface 242 toward the object end surface 241. The second slope 245 is at an obtuse angle with the image end surface 242. The first bevel 244 of each protrusion 246 at the central portion intersects the second bevel 245 of an adjacent protrusion 246.

At the time of photographing, light entering the lens barrel 10 from the light entrance hole 120 penetrates the optical portion 22 of the first lens 20a and enters the second lens 20b. Since the light-emitting surface 222 of the optical portion 22 of the second lens 20b is convex, when the light passes through the light-emitting surface 222 of the second lens 20b, A small amount of light is divergently reflected into the non-optical portion 24 of the second lens 20b. As shown in the optical path II in FIG. 2, a part of the light is reflected by the light-emitting surface 222 of the second lens 20b, and is emitted toward the object end surface 241 of the non-optical portion 24 of the second lens 22b at a large incident angle, since the object end surface 241 is In the plane, when the incident angle of the light is greater than the critical angle, the light is totally reflected on the object end surface 241 and is emitted toward the outer side surface 243 of the non-optical portion 24. At the same time, another portion of the light is refracted or reflected by the light incident surface 221 and the light exit surface 222 of the optical portion 22 during the penetration of the second lens 20b or toward the object end surface 241 or the image end surface 242 of the non-optical portion 24, and The object end surface 241 or the image end surface 242 is totally reflected by one or more times and then emitted toward the outer side surface 243 of the non-optical portion 24 of the second lens 20b. Since the protrusion 246 is formed on the outer side surface 243 of the non-optical portion 24, the first slope 244 and the second slope 245 of the protrusion 246 are inclined with respect to the object end surface 241 or the image end surface 242, so that the object end surface 241 or the image When the total reflected light on the end surface 242 is incident on the first inclined surface 244 or the second inclined surface 245 of the protrusion 246, the incident angle of the light is reduced, thereby changing the original traveling direction from the first inclined surface 244. Alternatively, the second inclined surface 245 is directly emitted outward or is reflected and then emitted outward from the object end surface 241 or the image end surface 242. Therefore, by the arrangement of the protrusions 246 on the outer side surface 243 of the non-optical portion 24 of the second lens 20b, total reflection of light in the edge region of the lens can be eliminated, thereby preventing the occurrence of stray light and improving the image quality.

The lens group 20 in the present embodiment includes three lenses 20a, 20b, and 20c, and the protrusions 246 are disposed on the outer side surface 243 of the non-optical portion 24 of the second lens 20b. It can be understood that the lens group 20 can also be One or more lenses are added according to the imaging requirements, and the protrusions 246 may also be disposed on the object end surface 241 or the image end surface 242 of the non-optical portion 24 of the second lens 20b, or may be disposed in any according to the requirements of the specific implementation. The outer side surface 243 of the non-optical portion 24 of the one or more lenses, the object end surface 241 or Like the end face 243. As shown in FIG. 4, a lens module according to a second embodiment of the present invention is different from the first embodiment in that all outer surfaces of the non-optical portion 34 of the second lens 30b, that is, the object end surface 341, Protrusions 346 are formed on both the end surface 342 and the outer side surface 343. As shown by the optical path IV in FIG. 4, a part of the light is reflected by the light-emitting surface 322 of the second lens 30b in the process of penetrating the second lens 30b, and is emitted toward the object end surface 341 of the non-optical portion 34 at a large incident angle. Since the protrusion 346 is formed on the section 341 of the object, the light is incident on the slope of the protrusion 346 of the object end surface 341, and the incident angle is smaller with respect to the incident end surface 241 of the object, so that it can be directly from the object. The end surface 341 is emitted outward or emitted from the outer side surface 343 of the non-optical portion 34 of the second lens 30b or the image end surface 342 after a small number of reflections. Similarly, in the process of penetrating the second lens 30b, each light entering the non-optical portion 34 is incident on the image end surface 342 or the outer side surface 343 of the non-optical portion 34, The arrangement of the protrusions 346 changes the magnitude of the incident angle, so that the second lens 30b can be smoothly emitted outwardly, thereby effectively eliminating total reflection of light in the edge region of the lens and avoiding generation of stray light.

As shown in FIG. 5, a lens module according to a third embodiment of the present invention is different from the second embodiment in that all outer surfaces of the non-optical portion 44 of the third lens 40c, that is, the object end surface 441 A plurality of protrusions 446 are also formed on the end surface 442 and the outer side surface 443, respectively. As shown in the optical path V and the optical path VI in FIG. 5, the action principle of the protrusion 446 provided on the outer surface of the non-optical portion 44 of the third lens 40c and the protrusion provided on the outer surface of the second lens 30b in the second embodiment are shown. The function of 346 is the same, so it will not be described here.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above is only a preferred embodiment of the present invention, and those skilled in the art will be familiar with the present invention. Equivalent modifications or variations made in accordance with the spirit of the invention are intended to be included within the scope of the following claims.

10‧‧‧Mirror tube

11‧‧‧Cylinder

12‧‧‧ front cover

120‧‧‧Into the light hole

20‧‧‧ lens group

20a‧‧‧first lens

20b‧‧‧second lens

20c‧‧‧ third lens

22‧‧‧Optical Department

221‧‧‧Into the glossy surface

222‧‧‧Glossy

24‧‧‧ Non-optical department

241‧‧‧ object end face

242‧‧‧like end face

243‧‧‧ outside side

Claims (6)

A lens module includes a lens barrel, a first lens, a second lens and a third lens, the lens barrel includes a barrel and a front cover formed on the end of the barrel near the object to be photographed, The first lens, the second lens and the third lens are fixed to the inner surface of the cylinder from the front cover, and the first lens, the second lens and the third lens respectively comprise an optical portion and a surrounding A non-optical portion of the optical portion is improved in that the non-optical portion of the first lens is disposed adjacent to the front cover and completely covers the front cover, and the outer surface of the non-optical portion of the first lens is a plane, the first The outer surface of the non-optical portion of the two lenses is provided with a plurality of tiny densely arranged projections. The lens module of claim 1, wherein the plurality of protrusions are continuously arranged, and each of the protrusions includes a first slope and a second slope that are inclined outward from the outer surface of the non-optical portion and are adjacent to each other. The angle between the first inclined surface and the second inclined surface varies between 1° and 179°, and each of the first inclined surfaces is parallel to each other, and each of the second inclined surfaces is parallel to each other. The lens module of claim 1, wherein the inner surface of the lens barrel is black. The lens module of claim 1, wherein each of the optical portions includes a light incident surface and an opposite light exiting surface, and each of the non-optical portions includes an object end surface extending from the light incident surface and extending from the light emitting surface. The image end surface extending outwardly and the outer side surface connected between the object end surface and the outer peripheral edge of the image end surface are formed on the outer side surface of the second lens. The lens module of claim 4, wherein the protrusion is further formed on the object end surface and the image end surface of the second lens. The lens module of claim 1, wherein the protrusion is also formed on an outer surface of the non-optical portion of the third lens.