TWI235872B - Automatic focusing lens - Google Patents

Abstract

An automatic focusing lens which is applied to digital cameras comprises a coil seat, a lens seat, and an elasticity member. The coil seat comprises a coil winding externally in specific direction and a hollow with a stander on the bottom. The lens seat comprising permanent magnet on the surface is rotational in the hollow. The lens seat comprises a slanting guiding surface on one side near the stander. The elasticity member is against the other side of the lens seat, thus the guiding surface contacts the stander. When the coil electrifies, the coil produces magnetic force which is repulsive to the magnetic force of the permanent magnet of the lens seat that makes the lens seat rotate according to the guiding surface for changing the focal distance of the automatic focusing lens.

Description

1235872 V. Description of the invention (1) 'Technical field to which the invention belongs] A lens is applied to a digital camera, especially an autofocus lens. [Prior art]

There are many ways for people to commemorate the good times, and the most frequently used real photos are photos, so whether it is a trip, party, or even all memorable moments, you need to use a camera to record for users I will recall in the future that the thin and light design of the camera has been formed so far. Of course, the most popular digital cameras are even more so. I The current digital camera's focus structure can be roughly divided into two types: manual focus structure and auto focus structure. The manual focus structure can adjust the focus of the lens to the position where the image focus is the clearest. As for the auto focus structure, The image on the image sensor is used to focus on the target. Such an image sensor has a Charge Coupling Device (CCD) sensor or a complementary metal oxide semiconductor (C- MOS) sensor, which is controlled by the central processing unit set in the digital camera. At first the lens moves back and forth from its original position (still position). While the lens is still moving, the central processing unit passes through the lens from time to time. The image formed on the image sensor is checked, and then the lens stops at the position where the image is focused most clearly. In this case, the lens must be continuously driven back and forth along the ring cam. The ring cam is provided with a lens driving structure and is driven to rotate by the step motor to make the lens move back and forth when the step motor is rotated. When the lens moves back and forth, the CPU detects the moment when the image is in focus.

Page 8 1235872 V. Description of the invention (2) At the same time, a signal to stop the movement is sent to the lens. Then the lens stops at the position where the image is best in focus (still position), and when the lens is returned to the original position, the ring cam starts to rotate again. When the lens is turned back to the original position, a photo interrupter located next to the lens cylinder is used to detect the original position of the lens by using a shutter provided on the edge of the lens cylinder. This shutter will block the transmissive photo interrupter Light. The moment the photo interrupter detects the original position, the lens movement stops at this original position. If so, the lens of such a digital camera autofocus system must be continuously driven continuously, and the detection of the image must always be continuous. After each image is captured, the lens must return to its original position, so the focus adjustment steps of these lenses are quite It is time consuming, and in most cases, the best timing for image capture will be missed. Of course, because such a structure includes a stepper motor, a ring cam, and a photo interrupter, it costs a lot of money. Please refer to the cross-sectional view of the autofocus structure of the conventional digital camera shown in "Figure 1" and the perspective view of the autofocus structure of the conventional digital camera shown in "Figure 2". When the stepping motor 1 moves from the center of the digital camera When the processor receives the start signal, the stepping motor 1 starts to rotate, and the stepping motor gear 2 is engaged with the ring cam gear 3 provided on the edge of the ring cam 4 and also starts to rotate. Then, the ring cam 4 The gear 3 meshes with the stepping motor gear 2 and starts to rotate, and the position sensing lever 5 starts to move back and forth (up and down) along the slope surface of the ring cam 4, so the entire lens assembly 6 starts to be set along the lens assembly. Six guides 7 move back and forth. One side of the lens cylinder is made like a sleeve, and a position sensing rod 5 is provided on the sleeve, which becomes a part of the sleeve, protrudes from the sleeve, and the sleeve of the lens assembly 6

Page 91235872 V. Description of the invention (3) The outermost part of the barrel is provided with a bearing portion 8 which moves back and forth along the guide rail 7, and a position-stabilizing fork 9 is made on the other side of the lens cylinder to become a lens cylinder. A part of the position stabilizing fork 9 is provided with a position stabilizing pin 10 ° between the end of the position stabilizing fork 9 and the bearing part 8 and the guide 7 together with the position stabilizing fork 9 and the position stabilizing pin 10 to support the lens assembly 6 together. The lens assembly 6 is always pressed by the coil spring 12 toward the image sensor 11 so that the tip of the position sensing lever 5 always properly contacts the slope surface of the ring cam 4 without failure. When the power switch of the digital camera is turned on, the image is formed on the image sensor 11 through the lens assembly 6. Once the switch of the autofocus structure is turned on, the image focus is immediately transmitted to the center in a continuous manner. To check the image formed on the image sensor 11. When the focus of the image is sharpest, the CPU gives a stop check signal, and even if the stepping motor 1 stops, the shutter is relaxed and the image is captured. After these steps, the lens assembly 6 must return to the original position (rest position). On the edge of the ring cam 4, a sensing shutter blade 13 of this position is provided. After capturing the image, the ring cam 4 starts to rotate again, returning the lens assembly 6 to the original position, and when the sensing shutter blade 13 enters the slot of the photo interrupter 14, the photo interrupter 1 4 The light beam is blocked by the sensing shutter blades 13 and the ring cam 4 stops here immediately, so that the lens assembly 6 can return and stop at its original position of φ. Cheng is in his original position. The above-mentioned lens assembly 6 must be moved back and forth to allow the central processing unit to check the condition of the image. This best way to search for the focus, borrowing machinery

Page 10 1235872 V. Description of the invention (4) The repetitive image check of the continuous and continuous lens movement is necessarily time-consuming, and the best shutter timing will be missed. In addition, such a complex structure is difficult to combine and must be fine-tuned. Furthermore, its components are also quite expensive, so it is best to have a very simple structure that uses few and inexpensive components, and saves focusing time and reduces Power consumption and reduced space used. [Summary of the Invention] The main object of the present invention is to provide an autofocus lens to achieve a very simple structure, use few and inexpensive components, and save focusing time, reduce power consumption, and reduce the use of The purpose of space. The autofocus lens disclosed in the present invention is applied to a digital camera. The autofocus lens includes a coil holder, a lens holder, and an elastic element. The coil holder has a coil wound in a specific direction on the outside, and is provided with a housing. A hole is provided at the bottom of the accommodating hole. A permanent magnetic pole is arranged on the surface of the lens seat, and is rotatably provided in the accommodating hole. The guide surface is adjacent to the abutment, and the guide surface is an inclined surface. Resist the other end of the lens holder to make the guide surface permanently contact the abutment. When the coil is energized, a magnetic force is generated. The permanent magnetic pole of the lens holder is mutually exclusive, so that the lens holder rotates according to the guide surface and according to the design of the guide surface. Control the lens mount to move up and down while Lu changes the focal length. Of course, the lens holder can be made of rare earth, and the lens holder can be provided with permanent magnetic poles through the action of magnetization, so the lens holder can rotate in the accommodation hole of the coil holder.

Page 111235872 V. Description of the invention (5) In order to gain a better understanding of the purpose, structural features and functions of this creation, the detailed description with the illustrations is as follows: [Embodiment of the dagger step] As shown in "Figure 3" Shows the self-exploded view of the first embodiment of the present invention, and the combination of the first and second = master focus lens of the present invention as shown in "Fig. 4". The automatic camera disclosed in the present invention is moved to a digital camera. Autofocus lenses include a wired head shovel application. It is provided with a accommodating hole 22 on the outside, which accommodates: =; = ”221 'The lens holder 30 is provided with a lens 33, and the lens holder 3 is made of a rare earth material, and the surface is provided with a permanent magnetic pole 3 丨, which can be rotated. In order to have a leading surface 32 at the-end, the guiding surface 32 is provided with a hole adjacent to the valley: the guiding surface is an elastic element 4. Resisting to the mirror = 丄, sub-and: Health =: = = 221, and a current is passed to the coil 21 At this time, the head base 301ΐ, the magnetic pole 31 and the coil base 20 are mutually exclusive, so that the head base 30 rotates according to the guide surface 32, thereby changing the focal length. It scares the mirror as shown in Fig. 5 of the first embodiment of the present invention. Another combination of automatic confrontation-Baiyin, the lens holder 30 is set at the capacity ^ autofocus lens element 40 resists the lens holder 3Q, and the other item is per-sex resister 221, and the coil 21 is connected ^ Therefore, the permanent magnetic pole 31 that brought the guide surface 32 into contact with the coil holder 2 () generates magnetic force, and the lens holder 30 turns, and the reorganization also repels the lens holder 30 according to the guide surface 32 to rotate the lens holder 30 rotation; J : 疋: The guide surface 32 is a slanted surface, so while moving, at the same time two = seat 3 ° can face the line .... The outer side ', ^ makes the lens holder 3 0 abut against the abutment 2 2 1,

Page 121235872___ V. Description of the invention (6) __ Conversely, the lens holder 30 can move towards the inside of the coil holder 2 0, and _ pieces 40 will also make the lens holder 30 hold against the contact piece 2 21, so Taking t / simultaneous elastic element as a matter of course, using rare earth as the material of the lens holder 30, " mainly changing the η focal length. Due to the action of magnetization, the lens holder 30 can be permanently blocked because the lens holder 30 can be rotated in the accommodation hole 22 of the coil holder 20 through the lens holder 30. Pole 3 1 'So the exploded view of the second embodiment of the present invention as shown in "Figure 6" and the combined view of the focusing lens of the second real focus lens of the present invention as shown in "Figure 7". The autofocus digital camera disclosed, this autofocus lens includes a coil ;: the head is applied to the outside of 21, ... has a receiving hole: the lens holder 30 is provided inside the lens holder 30 and the lens holder 30 The material of the surface is a rare earth material, the surface is provided with a permanent magnetic pole 3 i, the hole 22 is arranged, and the-end has a guide surface 32, and the guide surface Rongya and the guide surface 32 are inclined surfaces. Hold the other end of the lens holder 30 so that the guide surface 32 contacts the contact piece 221, and a current is passed through the coil 21 to generate magnetic force. The permanent magnetic pole 3 of the lens holder 30 and the coil holder 2 are mutually exclusive. Rotate the lens mount 30 according to the guide surface 32 to change the focal length. As shown in FIG. 8, another combination view of the autofocus lens according to the second embodiment of the present invention, when the lens holder 30 is disposed in the accommodation hole 22, the elastic member 40 abuts against the lens holder 3. 〇 the other end, so that the guide surface 32 will contact the abutment 2 2 1, and when the coil 2 1 is energized, a magnetic force is generated. The permanent magnetic pole 31 of the lens holder 3 Q and the coil holder 2 are mutually exclusive, making the lens holder 3 〇 Change to the “cross focus” according to the rotation of the guide surface 32, that is, because the guide surface 32 is a slope, so

1235872 V. Description of the invention (7) During the rotation of the lens holder 30, the lens holder 30 can move toward the outside of the coil holder 20, and at the same time, the elastic member 40 will also make the lens holder 30 hold against the contact member 2 2 1. Conversely, the lens holder 30 can move toward the inside of the coil holder 20, and at the same time, the elastic member 40 can also make the lens holder 30 hold against the contact member 2 21, so the focal length can be changed. Of course, the use of rare earth as the material of the surface of the lens holder 30 is mainly because the surface of the lens holder 30 can be provided with a permanent magnetic pole 3 through the action of magnetization, so the lens holder 30 can be accommodated in the coil holder 20. Hole 2 2 rotates. The above are only the preferred embodiments of this creation, and are not intended to limit the scope of implementation of this creation; that is, all equivalent changes and modifications made in accordance with the scope of the patent application for this creation are covered by the scope of this creation patent .

Page 141235872_ Brief description of the drawings. Figure 1 is a cross-sectional view of the autofocus structure of a conventional digital camera. Figure 2 is a perspective view of the autofocus structure of a conventional digital camera. Figure 3 is an automatic view of the first embodiment of the present invention. Exploded view of the focusing lens; FIG. 4 is a combined view of the autofocus lens of the first embodiment of the present invention, and FIG. 5 is another combined view of the autofocus lens of the first embodiment of the present invention; FIG. 6 is the present invention Exploded view of the autofocus lens of the second embodiment; FIG. 7 is a combined view of the autofocus lens of the second embodiment of the present invention; and FIG. 8 is another combined view of the autofocus lens of the second embodiment of the present invention .

[Illustration of Symbols] Stepping Motor Stepping Motor Gear Ring Cam Gear Ring Cam Position Sensing Rod Lens Assembly Guide Bearing Bearing Position Stabilizing Fork

Page 15 1235872 Simple description of the position stabilizing pin Image sensor Coil spring Sensing shutter blade Photointerrupter Coil holder Coil Hold? L contact lens holder permanent magnetic pole guide surface lens elastic element

Page 16

Claims (1)

1235872 VI. Scope of patent application 1. An autofocus lens used in a digital camera, the autofocus lens includes: a coil holder with a coil wound in a specific direction on the outside, and an accommodation hole is provided, An abutment is provided at the bottom of the accommodating hole; a lens holder with permanent magnetic poles on the surface is rotatably disposed on the accommodating hole, and has a guide surface at one end, the guide surface is adjacent to the abutment, and the guide surface is Is an inclined surface; and an elastic element abuts against the other end of the lens holder so that the guide surface contacts the abutment member and 'generates a magnetic force' when the coil is energized, and the permanent magnetic pole of the lens holder is mutually exclusive, The lens holder is rotated according to the guide surface to change the focal length. 2. The autofocus lens according to item 1 of the scope of patent application, wherein a lens is arranged inside the lens holder. 3. The autofocus lens described in item 1 of the scope of patent application, wherein the material of the lens holder is a rare earth material. 4. The autofocus lens according to item 1 of the scope of patent application, wherein the material of the lens holder surface is a rare earth material. Page 17