LENS ASSEMBLY

A lens assembly is provided, including a barrel, defining an axial direction and including an object side and an image side, an inner circumferential wall of the barrel including a stage portion extending inwardly, a first barrel side wall and a second barrel side wall, the stage portion including a first stage face facing the image side, the first barrel side wall being oblique to the axial direction and located between the first stage face and the second barrel side wall; and at least one optical member, mounted to the barrel, including a first face facing the first stage face and a first optical member side wall abutted against the first barrel side wall.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a lens assembly.

Description of the Prior Art

Generally, a lens assembly includes a barrel and at least one optical member (for example, including a lens, a shading sheet, a spacer) which is disposed in the barrel. The barrel has an object side and an image side which opposite to each other axially, an inner circumferential wall of the barrel has a stage portion which is annular and near the object side, and the stage portion defines a light entrance hole which expands toward the object side. Through using a mechanic device to assemble a lens from the image side into the barrel and abut against the stage portion, an outer periphery of the lens is tight fit to the inner circumferential wall of the barrel to be assembled with each other. During the process of mounting the lens, the mechanic device exerts a pressure toward the stage portion to ensure the lens is stably assembled. However, the pressure could make the stage portion deform easily, positions of each optical member of the lens assembly could shift, and there may problems like lower assembly precision or lower efficiency of the lens assembly.

SUMMARY OF THE INVENTION

The major object of the present invention is to provide a lens assembly, and the lens assembly has a barrel which will deform easily and has a preferable assembly precision.

To achieve the above and other objects, a lens assembly is provided, including a barrel, defining an axial direction and including an object side and an image side, an inner circumferential wall of the barrel including a stage portion extending inwardly, a first barrel side wall and a second barrel side wall, the stage portion including a first stage face facing toward the image side, the first barrel side wall being oblique to the axial direction and located between the first stage face and the second barrel side wall; and at least one optical member, mounted to the barrel, including a first face facing the first stage face and a first optical member side wall abutted against the first barrel side wall.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer toFIGS. 1 to 4for a first preferred embodiment. A lens assembly1includes a barrel10and at least one optical member20.

The barrel10defines an axial direction A and includes an object side11and an image side12, an inner circumferential wall of the barrel10includes a stage portion13extending inwardly, a first barrel side wall14and a second barrel side wall15, the stage portion13includes a first stage face131facing toward the image side12, and the first barrel side wall14is oblique to the axial direction A and located between the first stage face131and the second barrel side wall15. The at least one optical member20is mounted to the barrel10and includes a first face21facing the first stage face131and a first optical member side wall22abutted against the first barrel side wall14, so that the stage portion13will not easily deform due to contact force in the axial direction A during the mounting process of the at least one optical member20, and the assembling precision would be preferable.

Please refer toFIGS. 3 and 4, the first barrel side wall14is transitionally connected to the first stage face131, the second barrel side wall15is parallel to the axial direction A, and the first stage face131is perpendicular to the axial direction A; however, the first stage face131may be designed to be oblique to the axial direction A. The first barrel side wall14is obliquely connected to the first stage face131and the second barrel side wall15, models of the first barrel side wall14tilting toward the axial direction A include at least one of an inclined plane, an inclined convex surface and an inclined concave surface, the first barrel side wall14and the first optical member side wall22are abutted against each other in at least one of three ways: multi-points contact, line contact and surface contact, so as to make a pressure of mounting the at least one optical member20disperse laterally to effectively prevent the stage portion13from being deformed because of directly bearing a forward force transmitting along the axial direction A. In this embodiment, a smallest inner diameter of the first barrel side wall14is equal to or smaller than a smallest outer diameter of the first optical member side wall22to make the at least one optical member20and the barrel10mounted to each other more stably. The first face21is perpendicular to the axial direction A and parallel to the first stage face131, there is a gap between the first face21and the first stage face13to ensure the stage portion13will not be pressed and deformed by the forward force along the axial direction A when mounting the at least one optical member20, but the first stage face131may also be designed to be oblique to the axial direction A. In this embodiment, the first barrel side wall14is an inclined plane which is annular, an included angle α between the inclined plane and the axial direction A is between 1 and 89 degrees, and the optical option is between 15 and 45 degrees which can stably abut against the at least one optical member20to effectively and laterally disperse the forward force when mounting the at least one optical member20.

It is understandable that when the first barrel side wall14is abutted against the first optical member side wall22, the first face21partly contacts the first stage face131but not abuts against the first stage face131.

Please refer toFIG. 3, the stage portion13further includes a slant face132which is oblique to the axial direction A and oppositely arranged relative to the first stage face131, and the slant face132defines a light entrance hole16which radially expands toward the object side11. A line which passes through an outer periphery of the slant face132and is parallel to the axial direction A is defined as a first straight line L1; a point which the first barrel side wall14contacts the first optical member side wall22is defined as a contact position P, a line which passes through the contact position P and parallel to the axial direction A is defined as a second straight line L2, and a distance D2between the second straight line L2and an inner periphery of the stage portion13is equal to or greater than ⅓ of a distance D1between the first straight line L1and the inner periphery of the stage portion13. InFIG. 3, the first barrel side wall14and the first optical member side wall22are in a face contact relationship and define a face contact area, and any point within the face contact area which matches the above definition (D2≥⅓×D1) can be defined as the contact position P; in other embodiments, the first optical member side wall may be arc-shaped, the first optical member side wall and the first barrel side wall are in a point contact relationship, and a tangent point of the first optical member side wall and the first barrel side wall is the contact position P. In this embodiment, the second straight line L2is near the first straight line L1, the contact position P corresponds to a position of the stage portion13which is axially thicker, a pressure along the axial direction A can be guided through the first barrel side wall14laterally or obliquely to the position of the stage portion13which is thicker and has greater structure strength, so a position of the stage portion13which is axially thinner can be prevented from force deformation.

The inner circumferential wall of the barrel10further includes a plurality of annular walls17which are steppedly arranged, and each said optical member20is abutted against one of the plurality of annular walls17to provide preferable assembling stability. Specifically, the at least one optical member20further includes a second optical member side wall23which extends along the axial direction A, the first optical member side wall22is connected to and between the second optical member side wall23and the first face21, and the second optical member side wall23is abutted against the second barrel side wall15to increase assembling stability. Preferably, an inner diameter of the second barrel side wall15is equal to or smaller than an outer diameter of the second optical member side wall23to prevent the at least one optical member20from moving toward the stage portion13excessively and further to maintain a distance between the first face12and the first stage face131. In other embodiments, the second barrel side wall may be also non-abutted against the second optical member side wall.

In a second preferred embodiment shown inFIGS. 5 and 6, the at least one optical member20afurther includes a second face24which is laterally connected to and between the second optical member side wall23aand the first optical member side wall22a, and an inner circumferential wall of the barrel10afurther includes a second stage face18which is lateral to the axial direction A and connected to the first barrel side wall14a; when the first barrel side wall14ais abutted against the first optical member side wall22a, the second face24is abutted against the second stage face18, and the second stage face18supports the at least one optical member20ato effectively prevent the first stage face131afrom directly contacting the first face21aand to provide preferable assembling stability. The second barrel side wall15aand the second optical member side wall23aare abutted against each other to increase a radial support and disperse a force along the axial direction A.

Please refer toFIG. 7for a third preferred embodiment. Compared with the second preferred embodiment, when the first barrel side wall14ais abutted against the first optical member side wall22a, the second face24is abutted against the second stage face18, and the second stage face18supports the at least one optical member20ato prevent the first stage face131afrom directly contacting the first face21aand to provide preferable assembling stability. The second barrel side wall15aand the second optical member side wall23aare spacingly arranged to have a greater range of tolerance, and it is convenient to mount the second barrel side wall15aand the second optical member side wall23a.

Please refer toFIG. 8for a fourth preferred embodiment. Compared with the second preferred embodiment, when the first barrel side wall14ais abutted against the first optical member side wall22a, the second face24does not contact the second stage face18, and the second barrel side wall15aand the second optical member side wall23aare abutted against each other to prevent the first stage face131afrom directly contacting the first face21a, and a pressure of mounting the at least one optical member20acan be obliquely dispersed through the first barrel side wall14aand laterally dispersed through the second barrel side wall15a, so as to largely decrease a force exerted on the stage portion13aalong the axial direction A to effectively prevent the stage portion13afrom force deformation.

Please refer to a fifth preferred embodiment shown inFIGS. 9 and 10, the fifth preferred embodiment is a combination of the above mentioned first and second preferred embodiments. The lens assembly la includes the plurality of optical members20,20a, the plurality of optical members20,20amay include at least one of a lens, a spacer ring, an optical filter and a junk ring which can be arranged if needed. The inner circumferential wall of the barrel10further includes the plurality of first barrel side walls14band the plurality of second barrel side walls15bwhich are located between two said first barrel side walls14bneighboring to each other, the plurality of second barrel side walls15bare steppedly arranged, the first optical member side wall22,22aof each said optical member20,20ais abutted against one said first barrel side wall14bto prevent the stage portion13bfrom force deformation and to prevent each said optical member20,20afrom abutting against each other.

Please refer toFIGS. 11, 12for a sixth preferred embodiment. Compared with the second preferred embodiment, the first stage face131ais perpendicular to the axial direction A, the second barrel side wall15cis oblique to the axial direction A, the inner circumferential wall of the barrel further includes a second stage face18which is perpendicular to the axial direction A and connected to and between the first barrel side wall14aand the second barrel side wall15c, and the first barrel side wall14ais connected to and between the first stage face131aand the second stage face18. The second optical member side wall23band the second barrel side wall15care oblique relative to the axial direction A, and the second face24and the second stage face18are perpendicular to the axial direction A. When the first barrel side wall14ais abutted against the first optical member side wall22a, the second optical member side wall23band the second barrel side wall15care obliquely abutted against each other to radially disperse forces effectively, and the second face24and the second stage face18can be further abutted against each other on the axial direction A to prevent the first stage face131afrom taking too much force and to prevent the position of the stage portion13awhich is axially thinner from deformation. The first stage face131aand the first face21apositionably contact each other.

Please refer toFIGS. 13, 14for a seventh preferred embodiment. Compared with the sixth preferred embodiment, the first stage face131ais perpendicular to the axial direction A, the second barrel side wall15cis oblique to the axial direction A, the inner circumferential wall of the barrel further includes a second stage face18awhich is oblique to the axial direction A and connected to and between the first barrel side wall14aand the second barrel side wall15c, and the first barrel side wall14ais connected to and between the first stage face131aand the second stage face18a. Specifically, the second optical member side wall23b, the second face24a, the second barrel side wall15cand the second stage face18aare oblique to the axial direction A; when the first barrel side wall14ais abutted against the first optical member side wall22a, the second face24ais obliquely abutted against the second stage face18a, and the second optical member side wall23bis obliquely abutted against the second barrel side wall15cto effectively disperse the force along the axial direction A and to provide preferable assembling stability.

Please refer toFIGS. 15, 16for an eighth preferred embodiment. Compared with the second preferred embodiment, the first stage face131bextends obliquely toward the object side11relative to the axial direction A, the first stage face131band the first barrel side wall14ahave different slopes, and the first face21band the first stage face131bextend toward the object side11relative to the axial direction A; when the first barrel side wall14ais abutted against the first optical member side wall22a, and the first face21bis obliquely abutted against the first stage face131bto disperse the force laterally or obliquely in order to prevent force deformation.

Please refer to a ninth preferred embodiment shown inFIGS. 17 and 18, the ninth preferred embodiment is a combination of the above mentioned sixth and eighth preferred embodiments. The second barrel side wall15cand the second optical member side wall23bobliquely extend relative to the axial direction A, the first face21band the first stage face131bextend toward the object side11relative to the axial direction A, and the first barrel side wall14a, the second barrel side wall15cand the first stage face131bobliquely support the at least one optical member20b, so the pressure along the axial direction A can be effectively dispersed.

Please refer toFIGS. 19, 20for a tenth preferred embodiment. Compared with the eighth preferred embodiment, the first stage face131bextends obliquely toward the object side11relative to the axial direction A, the inner circumferential wall of the barrel further includes the second stage face18which is perpendicular to the axial direction A and connected to the second barrel side wall15dand a third barrel side wall19which is connected to and between the second stage face18and the first barrel side wall14c, the first barrel side wall14cand the first stage face131bare on a lowest face of the barrel (a same plane) and have same slopes, the first barrel side wall14cand the first stage face131bcan be respectively viewed as a part of the lowest face of the barrel, and the first optical member side wall22band the first face21bare on a same face of the optical member and have same slopes to disperse the force obliquely.

Please refer toFIGS. 21, 22for an eleventh preferred embodiment. Compared with the first preferred embodiment, the second barrel side wall15eis parallel to the axial direction A, the inner circumferential wall of the barrel10cfurther includes the third barrel side wall19awhich is connected to and between the first barrel side wall14dand the first stage face131c, the at least one optical member20cfurther includes a third optical member side wall25which is connected to and between the first optical member side wall22cand the first face21c, and the first barrel side wall14dis connected to and between the second barrel side wall15eand the third barrel side wall19a. In this embodiment, the third barrel side wall19aand the third optical member side wall25respectively extend along a direction parallel to the axial direction A; when the first barrel side wall14dis abutted against the first optical member side wall22c, the third barrel side wall19aabuts against the third optical member side wall25to increase the radial support; the first stage face131ccontacts the first face21c, and the assembling precision would be preferable.

Please refer toFIGS. 23, 24for a twelfth preferred embodiment. Compared with the eleventh preferred embodiment, the second barrel side wall15fand the second optical member side wall23cobliquely extend relative to the axial direction A, preferably, the first barrel side wall14dand the second barrel side wall15fextend relative to the axial direction A differently to provide support in different angles, so the stability and the force dispersion effect are preferable.

It is to be noted that in any of the above-mentioned embodiments, a transitional profile of the outer circumferential face of the optical member may be partly or completely correspond to a transitional profile of the inner circumferential face of the inner circumferential wall of the barrel.