TWI383124B - Concentricity checking apparatus and concentricity checking method - Google Patents

Description

Concentricity detecting device and method thereof

The invention relates to a concentricity detecting device, in particular to a concentricity detecting device and a concentricity detecting method applied to a lens module.

In recent years, with the development of optical products, the application range of lens modules has continued to expand, such as digital cameras and electronic products with camera functions. For electronic products, especially consumer electronic products, the development trend is lighter and thinner. The corresponding lens modules are also getting smaller and smaller, and the precision requirements are getting higher and higher. The assembly process of the module also requires higher precision and stability to ensure production efficiency and yield.

Generally, the assembling step of the lens module includes assembling an optical component such as an optical lens, a spacer, and a diaphragm into the lens barrel, and then assembling the lens barrel with the optical component into the lens holder. The lens barrel and the lens holder are generally connected by a mutual meshing structure, such as a threaded structure or a cam structure that is intermeshing. After the lens barrel is loaded into the lens holder, a step of detecting the concentricity between the lens barrel and the lens holder is further included. Generally, a light source is disposed on one side of the axial direction of the lens barrel, and the lens axis is A position sensing element is disposed near the focus position of the optical lens in the other side of the lens, and the light source is used to illuminate the lens barrel, the light enters the lens barrel, and then a spot is formed on the position sensing element. Manually rotating the lens barrel to rotate the lens barrel at a certain angle with respect to the lens holder, repeating the above steps, forming another spot on the sensing element at the position; comparing whether the distances of the two spot centers are offset from each other is an error Within the allowable range.

However, the practice of manually rotating the lens barrel is slow, the efficiency and precision are low, and due to the influence of human fatigue and mood, it is impossible to ensure that the required angle can be achieved every time the manual rotation is performed, sometimes it is more Big error.

In view of this, it is necessary to provide a concentricity detecting device and a concentricity detecting method with high efficiency and high precision.

A concentricity detecting device for detecting the axial concentricity between the lens holder and the lens barrel disposed in the lens holder. The concentricity detecting device includes a position recording device and at least one rotary driving device. The position recording device is used to record the position of the axis of the lens barrel. The rotary driving device is used to drive the rotation of the lens barrel around the axis of the lens barrel. The rotary drive includes a drive wheel. The periphery of the driving wheel is configured to mesh with the outer edge of the end of the barrel.

A concentricity detecting method for detecting the concentricity between the lens barrel and the lens holder, the concentricity detecting device comprising the following steps: providing a detecting platform, and positioning the lens holder and the lens barrel on the detecting platform; Providing a rotary driving device including a driving wheel having a structure in which a peripheral edge is engaged with an outer edge of the end of the lens barrel, and engaging the driving wheel with the lens barrel; and providing a position recording device for recording the position of the lens barrel a first position; activating the rotary driving device, causing the driving wheel to drive the lens barrel to rotate around a shaft of the lens barrel by a predetermined angle; and recording the position of the lens barrel by the position recording device as a second The position is determined whether the relative offset between the second position and the first position is within the range allowed by the error.

Compared with the prior art, the concentricity detecting device comprises a rotary driving device for driving the lens barrel to rotate a certain angle along its optical axis, and the rotary driving device can save manpower, reduce production cost, and greatly improve efficiency; The rotation angle of the driving wheel and the rotation angle of the lens barrel have a certain proportional relationship, and the rotation angle of the lens barrel can be precisely controlled by precisely controlling the rotation angle of the driving wheel. Therefore, the concentricity detecting method of the concentricity detecting device can improve the accuracy and efficiency of the axial concentricity detection between the lens barrel and the lens holder.

The invention will be further described in detail below with reference to the accompanying drawings.

Please refer to FIG. 1 and FIG. 2 , which are schematic diagrams showing the combination of the concentricity detecting device 100 and the lens module 200 to be detected according to the first embodiment of the present invention. The concentricity detecting apparatus 100 includes a detecting platform 12, a rotation driving device 14, and a position recording device 16. The lens module 200 includes a lens holder 22, a lens barrel 24 disposed in the lens holder 22 and engaged with the lens holder 22, and a lens group 26 disposed in the lens barrel. The concentricity detecting device 100 is configured to detect the axial concentricity between the lens barrel 24 and the lens holder 22 after the lens barrel 24 is assembled into the lens holder 22, that is, the axis of the lens barrel 24 and the lens holder 22 The positional deviation between the axes. A plurality of notches 242 are defined in the outer edge of one end of the lens barrel 24, and the plurality of notches 242 in the embodiment are uniformly disposed on the outer edge of the end of the lens barrel 24. The lens group 26 may be composed of one lens or two or more lenses. This embodiment takes a lens as an example.

The detecting platform 12 is provided with a placing groove 122 and a sliding groove 124 adjacent to the positioning groove 122. The bottom end of the mirror base 22 of this embodiment is square. Therefore, the placement groove 122 for placing the lens module 200 including the lens holder 22 is also designed to be square. Of course, the placement groove 122 can be changed according to the shape of the lens holder 22, and is not limited to the embodiment. A through hole 1222 is defined in the placement groove 122, and the placement groove 122 is stepped. The through hole 1222 is used to pass light. The sliding groove 124 is an elongated groove extending in a direction close to and away from the positioning groove 122.

The rotary driving device 14 includes a driver 142 and a driving wheel 144 connected to the driver 142 for driving the lens barrel 24 to rotate. The driver 142 may be a stepping motor, a servo motor, a DC motor, or the like. Of course, it may be other types of drivers, and is not limited to the embodiment. In this embodiment, the driving wheel 144 is a cylindrical body having a plurality of protrusions 1442 at one circumference, and the plurality of protrusions 1442 can be engaged with the notches 242 of the outer edge of the end portion of the lens barrel 24. The driving unit 142 is connected to the driving wheel 144 via a rotating shaft 146. One end of the rotating shaft 146 is connected to the center of the driving wheel 144, and the other end is connected to the driving unit 142. When the driving unit 142 is in operation, the rotating shaft 146 is rotated to drive the driving wheel. 144 rotates along its central axis. The rotary driving device 14 is disposed in cooperation with the sliding slot 124. The sliding slot 124 of the embodiment penetrates the slot of the detecting platform 12. The rotating shaft 146 passes through the sliding slot 124, the driving wheel 144 is located on the outer side of one surface of the detecting platform 12, and the driver 142 is located on the outer side of the other surface of the detecting platform 12, and the rotary driving device 14 can be along The chute 124 slides. When the lens module 200 is placed in the placement slot 122, the driving wheel 144 can slide along the sliding slot 124 and have its peripheral projection 1442 in meshing contact with the notch 242 of the outer edge of the end of the lens barrel 24.

The position recording device 16 includes a light source 162 and a position sensing element 164. The light source 162 is disposed on one side of the axial direction of the lens barrel 24. The position sensing element 164 is located on the other side of the lens barrel 24 opposite to the position of the light source 162. Generally, the position sensing element 164 is disposed near the focus of the lens group 26 for The light spot obtained by the light source 162 passing through the lens group 26 in the lens barrel 24 is sensed. In this embodiment, the optical axis of the lens group 26 and the axis of the lens barrel 24 are approximately coincident, so that the light spot records the mirror. The axial position of the barrel 24. The position sensing component 164 can be a light sensitive component, such as a Charge Coupled Device (CCD) or the like.

The embodiment further includes a rotation control device (not shown) for controlling the rotation of the rotary drive unit 14 to the lens barrel 24. The rotation driving device 14 can precisely control the rotation angle of the lens barrel 24 according to the proportional relationship between the rotation angle of the lens barrel 24, and the rotation direction of the lens barrel 24 when the rotation driving device 14 rotates by 90 degrees, then the rotation driving device The ratio of the rotation angle between the 14 and the lens barrel 24 is 2:1. If the lens barrel 24 needs to be rotated by 90 degrees, it is only necessary to rotate the rotation control device 14 to rotate the rotation driving device 14 by 180 degrees.

The process of detecting the concentricity between the lens barrel 24 and the lens holder 22 by the concentricity detecting device 100 is as follows: (1) placing the lens module 200 including the lens holder 22 and the lens barrel 24 to be detected. (2) sliding the rotary driving device 14 along the sliding slot 124 to the meshing contact between the driving wheel 144 and the lens barrel 24; (3) turning on the light source 162 to illuminate the lens barrel 24, so that the light source 162 emits The light obtains a first spot on the position sensing element 164; (4) The rotation driving device 14 is activated to rotate the lens barrel 24 around the axis of the lens barrel 24 by an angle θ. In this embodiment, θ=180° is taken as an example; (5) Step (3) is repeated to sense the position. A second spot is obtained on the component 164, and the offset of the center of the second spot relative to the first spot is compared, and it is determined whether the offset is within the error tolerance range. If so, the lens barrel 24 and the mirror The axial concentricity between the seats 22 meets the requirements; if not, the optical axis concentricity between the lens barrel 24 and the lens holder 22 does not meet the requirements. It can be understood that the sequence of steps of the above detection process can be appropriately adjusted according to actual conditions, and the order of step (2) and step (3) can be interchanged.

In this embodiment, the offset of the two spots is compared once by rotating 180°. In practical applications, other angles can be rotated, and multiple data can be measured multiple times to obtain higher detection accuracy. In the steps (3) and (5), since the lens holder 22 is not moved, the lens barrel 24 is rotated, so that the first spot and the second spot recorded by the position sensing element 164 can be compared with the rotation of the lens barrel 24 The relative positional change of the lens barrel 24 and the lens holder 22 can be understood. The position recording device 16 can be of other forms as long as the axial position of the lens barrel 24 can be recorded.

It can be understood that the shape of the driving wheel 144 can also be designed to provide a plurality of protrusions on the periphery of a positive polygonal prism, and is not limited to the embodiment. It can also be understood that the cooperation relationship between the rotary driving device 14 and the detecting platform 12 can be other manners, as long as the driving wheel 144 can be moved away from and close to the positioning slot 122, for example, the sliding slot 124 has a bottom surface. The slotted wheel 144 is placed in the slot and slidable along the slot.

Compared with the prior art, the concentricity detecting apparatus 100 of the present embodiment includes a rotary driving device 14 for driving the lens barrel 24 to rotate along a certain angle thereof, and the rotary driving device 14 can save manpower, reduce production cost, and improve efficiency. Also greatly improved; and since the rotation of the rotary driving device 14 is controlled by the rotation control means, the rotation of the lens barrel 24 can be controlled more precisely.

Referring to FIG. 3, the present invention provides a concentricity detecting apparatus 300 of the second embodiment. The concentricity detecting device 300 is substantially the same as the concentricity detecting device 300 of the first embodiment, except that the concentricity detecting device 300 of the present embodiment includes two rotating driving devices 14 and two rotating drive devices 14 Corresponding to the chute 324 of the detecting platform 32 of the embodiment. The two rotary drives 14 collectively act on the lens barrel 24 to rotate the lens barrel 24. It can be understood that the number of the rotary driving devices 14 may also be three or more, depending on actual needs, and is not limited to the embodiment.

Referring to FIG. 4, the present invention also provides a concentricity detecting apparatus 400 of the third embodiment. The concentricity detecting device 400 is substantially the same as the concentricity detecting device 100 of the first embodiment, except that the meshing relationship between the driving wheel 444 and the lens barrel 54 of the concentricity detecting device 400 of the embodiment is a driving wheel. The inter-engagement between the notch 4442 of the peripheral edge of the 444 and the protrusion 542 of the outer edge of the end. Of course, the engagement between the driving wheel 444 and the lens barrel 54 can also be by other means, and is not limited to the embodiment.

The process of detecting the concentricity between the barrel 24 and the lens holder 22 by the concentricity detecting devices 300 and 400 is similar to the detection process using the concentricity detecting device 100, and details are not described herein again.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and those skilled in the art will be able to make equivalent modifications or changes in accordance with the spirit of the present invention. It should be covered by the following patent application.

100,300,400‧‧‧Concentricity testing equipment

122‧‧‧Place slot

124,324‧‧‧ chute

142‧‧‧ drive

146‧‧‧ shaft

162‧‧‧Light source

1442, 542‧‧ ‧ raised

22‧‧‧Mirror base

242, 4442 ‧ ‧ gap

12,32‧‧‧Testing platform

1222‧‧‧through hole

14‧‧‧Rotary drive

144,444‧‧‧Drive wheel

16‧‧‧Location Recording Device

164‧‧‧ position sensing components

200‧‧‧ lens module

24,54‧‧‧Mirror tube

26‧‧‧ lens group

1 is a perspective view showing a combination of a concentricity detecting device and a lens module according to a first embodiment of the present invention.

Figure 2 is a schematic cross-sectional view taken along line II-II of Figure 1.

3 and FIG. 4 are respectively a perspective view showing a combination of a concentricity detecting device and a lens module according to the second and third embodiments of the present invention.

100‧‧‧Concentricity testing equipment

122‧‧‧Place slot

1442‧‧‧ bumps

22‧‧‧Mirror base

242‧‧‧ gap

12‧‧‧Testing platform

124‧‧‧Chute

200‧‧‧ lens module

24‧‧‧Mirror tube

Claims (9)

A concentricity detecting device for detecting the axial concentricity between the lens holder and the lens barrel disposed in the lens holder, the concentricity detecting device comprising a position recording device for recording the axial position of the lens barrel, The concentricity detecting apparatus further includes at least one rotation driving device for driving the lens barrel to rotate about the axis of the lens barrel, and a detecting platform, wherein the at least one rotating driving device includes a driving wheel, The periphery of the driving wheel is disposed to engage with the outer edge of the end of the lens barrel, and the detecting platform surface is provided with a placing groove and a sliding groove for placing the lens holder and the lens barrel, the sliding groove The slit is for a narrow groove and extends in a direction toward and away from the placement groove for sliding the rotary drive along the slide. The concentricity detecting apparatus of claim 1, wherein the at least one rotary driving device further comprises a driver for driving the driving wheel to rotate. The concentricity detecting apparatus according to claim 2, wherein the at least one rotary driving device comprises a rotation control device for controlling driving of the driving wheel by the driver. The concentricity detecting device according to claim 1, wherein the position recording device comprises a light source and a position sensing element, and the light source and the position sensing element are respectively disposed on the lens barrel along the lens barrel axis. On both sides of the heart direction, the light source is used to emit light that is irradiated in the axial direction of the lens barrel, and the position sensing element is configured to sense a spot formed by the light passing through the lens barrel. The concentricity detecting device according to claim 1, wherein the driving wheel has a plurality of protrusions at a periphery thereof for engaging with the notch when the outer edge of the barrel end is notched. The concentricity detecting device according to claim 1, wherein the driving wheel has a plurality of notches at the periphery thereof for engaging the convex contact when the outer edge of the end of the lens barrel is convex. A concentricity detecting method for detecting the axial concentricity between the lens holder and the lens barrel disposed in the lens holder, the concentricity detecting method comprising the steps of: providing a detecting platform, and setting a surface of the detecting platform Positioning a slot and a sliding slot, the sliding slot is a narrow groove and extending in a direction close to and away from the positioning slot; the mirror base and the lens barrel are disposed in the positioning slot of the detecting platform; providing a peripheral edge and a lens barrel a rotating driving device for driving the wheel with the outer edge of the end engaging, and sliding the rotary driving device along the sliding groove to the driving wheel to engage with the lens barrel; providing a position recording device for recording the mirror Positioning the cylinder as a first position; activating the rotary driving device to cause the driving wheel to drive the lens barrel to rotate by a predetermined angle with respect to an axis of the lens barrel; and recording the lens barrel by using the position recording device The position is the second position, and it is determined whether the relative offset between the second position and the first position is within the range allowed by the error. The concentricity detecting method according to claim 7, wherein the rotary driving device further includes a driver for driving the driving wheel to rotate. The concentricity detecting method according to claim 7, wherein the position recording device comprises a light source and a position sensing element, and the step of recording the position of the lens barrel is: the light source and the position sense The measuring elements are respectively disposed on two sides of the lens barrel along the axial direction of the lens barrel to activate the light source Light is emitted, and the position sensing element senses a spot formed by the light passing through the lens barrel.