CN2544293Y - Objective lens carrier - Google Patents

Abstract

The utility model relates to an objective bears device, by with the upper and lower supporting part one end of non-parallel be connected to the objective frame, the other end is connected to the support arm fixing base to make the objective that sets up in the objective frame can not produce the inclination at skew (Yang), and have elastic support arm fixing base and also make the high frequency resonance frequency move to the frequency range that can restrain, therefore promote the stability of optical read-write head when reading and writing.

Description

Objective lens carrier

technical field

The utility model relates to a mechanical structure of an optical part, in particular to an objective lens carrying device.

technical background

The technology of using laser beams (such as semiconductor lasers) to read and record on optical recording media (such as CD or DVD discs) has long been known. The laser beam is focused on the surface of the optical disc by the objective lens in the optical pickup head. The track (track), and then use the optical detector (photo detector) to convert the reflected light from the optical disc into a reproduction signal, and then the data recorded on the optical disc can be obtained. In the process of reading the data, it is also necessary Obtain the tracking signal (TS) and focusing signal (FS) from the return light, and control the tracking actuator (tracking actuator) and focusing actuator (focusing actuator) to move in a timely manner according to the tracking signal and focusing signal The objective lens ensures that the laser beam can be correctly focused on the predetermined track on the surface of the optical disc.

In order to complete the servo operation of tracking and focusing, the objective lens must be free to move in the direction of the optical axis (focusing direction) and the radial direction of the optical disc (tracking direction), so a special The carrying device supports the objective lens and provides stable mobility. Known objective lens carrying devices generally include the following types:

1. Wire-supported type: For example, it is disclosed in US Patent No. 5381273, No. 5555623 and No. 5587845. In this design, the objective lens is supported by four elastic metal wires (such as stainless copper wires), these metal wires are parallel to each other, one end of which is fixed, and the other end is connected to the objective lens holder (lens holder), so The objective lens frame and the objective lens can move in two different directions under the promotion of the tracking driver and the focusing driver to complete the servo operation of tracking and focusing, but this design will cause the servo operation of tracking and focusing to The four metal wires are twisted, causing errors in tracking and focusing operations.

2. Utilize the objective lens carrying device of sheet spring (leaf spring): disclose a kind of mode that utilizes four parallel leaf springs to support objective lens in the U.S. Patent No. 5892628 for example, then disclose a A technology that only uses two parallel upper elastic pieces and lower elastic pieces to support the objective lens, but both of them are difficult to complete in terms of production and assembly.

3. Rotating and sliding type objective lens carrying device (axial sliding and rotating type device): as disclosed in Fig. 1 of U.S. Patent No. 5,587,845, the objective lens holder and the objective lens of this carrying device are installed on a supporting shaft (supporting shaft), And it can slide along the axial direction of the bearing shaft under the promotion of the tracking driver and the focus driver, or make a swinging motion with the bearing shaft as the axis to complete the servo operation of tracking and focusing, but it must accurately control the objective lens The matching size of the frame and the carrying shaft will increase the difficulty of manufacture, and once the carrying shaft and the objective lens frame are not well matched, it will easily cause the objective lens frame to shake.

But no matter what kind of objective lens carrying device is used, when the optical read-write head reads the optical disc, the inclination angle of the objective lens in the tangential direction of the track will change, which will affect the reading effect. Therefore, another objective lens carrying device is designed. It is necessary to use a device to improve the above-mentioned inclination angle change and improve the reading effect.

Contents of the invention

The main purpose of this utility model is to provide an objective lens carrying device, so that when the optical read-write head reads and writes the optical disc, the objective lens will not be tilted when it deviates from the steering (Yawing), and the high-frequency resonance frequency will be moved to a suppressable In the frequency range, to improve the stability of the optical read-write head when reading and writing.

The purpose of this utility model is achieved in that:

A kind of objective lens carrying device, is used for carrying an objective lens in the optical system of optical pick-up head, and this device comprises:

An objective lens frame has a through receiving hole for carrying the objective lens;

A support arm holder, which has elasticity and is located at a fixed position relative to the optical axis of the objective lens; and

An upper support part and a lower support part correspond to each other, and any one of the support parts has elasticity, one end is connected to the objective lens frame, and the other end is connected to the support arm fixing seat. After the two support parts are extended, they cross the support arm The positions of the mounts intersect. as well as

The upper and lower support parts respectively have a plurality of support arms parallel to each other, and each of the support arms corresponds to one of the support arms of the other group, and after the two corresponding to each other are extended, after crossing the support arm The positions of the mounts intersect.

The support arm fixing seat has a base and an elastic body, wherein the elastic body is arranged on one side of the base and connected with the upper and lower supporting parts.

The elastomer is a thin plate.

According to the objective lens carrying device disclosed in the utility model, it has the following positive effects:

1. Since the objective lens carrying device disclosed in the utility model is used to carry the objective lens in the optical system of the optical pickup, the device includes an objective lens frame, a support arm fixing seat, an upper support portion and a lower support portion, wherein the objective lens The frame is used to carry the objective lens, and the support arm fixing seat is elastic, and is located at a fixed position relative to the optical axis of the objective lens, while the upper and lower support parts correspond to each other, and any support part is elastic, and one end is connected to the objective lens The other end is connected to the supporting arm fixing seat, and the two supporting parts intersect at a position beyond the supporting arm fixing seat after being extended. Therefore, when the optical read-write head reads the disc by the two non-parallel support portions of the present invention and the elastic support arm fixing seat, the oblique angles of the objective lens in opposite directions caused by the two will cancel each other out, so that The objective lens will not produce an inclination when it deviates from the steering;

2. The flexible support arm fixing seat of the utility model moves the high-frequency resonance frequency to a suppressable frequency range, so that it will not resonate with other components, and the damping can be maximized without adverse effects of the resonance mode. In the high-frequency frequency domain, the high-frequency resonant frequency can also be damped to improve the stability of the optical read-write head when reading and writing.

Description of drawings

Fig. 1 is the top view of the utility model;

The side view of Fig. 2 the utility model;

Fig. 3 is the schematic diagram of the objective lens carrying device of the present utility model in six degrees of freedom;

Fig. 4 When the optical read-write head reads the optical disc, the tilt angle of the objective lens due to the upper and lower parallel support parts is caused by the deviation from the steering (Yawing);

Fig. 5 When the optical read/write head reads the optical disc, the tilt angle of the objective lens due to the non-elasticity of the support arm holder;

Fig. 6 is a schematic diagram showing that when the optical read/write head of the present invention reads an optical disc, the oblique angle of the objective lens will not deviate from the yawing due to the non-parallel upper and lower support parts and the elastic support arm fixing seat. Part number comparison:

Objective lens holder 10

Storage hole (access hole) 11

Support arm holder 20, 20

Base 21

Elastomer 22

Upper supporting portion (upper supporting portion) 30, 30’

The first support arm (supporting arm) 31

Second support arm 32

Lower supporting portion (bottom supporting portion) 40, 40’

The third support arm 41

Fourth support arm 42

Objective lens 50

Detailed ways

In order to have a further understanding of the purpose, structural features and functions of the utility model, hereby cooperate with the drawings to describe in detail as follows:

As shown in Fig. 1, 2 and Fig. 3, the objective lens carrier device disclosed by the utility model is used to carry the objective lens 50 (objectiv lens) in the optical system of the optical pick-up head, and this device includes objective lens frame 10, support arm The fixing seat 20 , the upper supporting part 30 and the lower supporting part 40 .

The objective lens holder 10 (Objective lens holder) has a through receiving hole 11 (accesshole), used to carry the objective lens 50 that focuses the laser beam on the data recording surface of the optical disc, and this objective lens holder 10 can be in the tracking direction TD with the objective lens 50 (Tracking direction) and the radial direction of the optical disc and the focusing direction FD (Focusing direction) movement, wherein the tracking direction TD is exactly the radial direction of the optical disc, and the focusing direction is exactly the optical axis direction of the laser beam or the objective lens 50.

The supporting arm fixing seat 20 has elasticity, and is located at a fixed position relative to the optical axis of the objective lens. The supporting arm fixing seat 20 has a base 21 and an elastic body 22, wherein the elastic body 22 is located on one side of the base 21, and is sheet.

The upper supporting portion 30 (upper supporting portion) and the lower supporting portion 40 (bottom supporting portion), both correspond to each other, and any supporting portion 30, 40 has elasticity, one end is connected to the objective lens holder 10, and the other end is connected to the support arm for fixing After the seat 20 and the two supporting parts 30 and 40 are extended, they intersect at a position beyond the support arm fixing seat 20 .

And upper supporting part 30 has the first supporting arm 31 (supporting arm) and the second supporting arm 32 that are parallel to each other, and first, second supporting arm 31,32 one ends are connected with objective lens holder 10, and the other end is connected with supporting arm holder. The elastic body 22 of 20, the lower support part 40 also has the third support arm 41 and the fourth support arm 42 that are parallel to each other, and the third and fourth support arms 41, 42 are connected to the objective lens frame 10 at one end, and connected to the support at the other end. The elastic body 22 of the arm fixing seat 20, and the first support arm 31 corresponds to the third support arm 41, the second support arm 32 corresponds to the fourth support arm 42, and the two corresponding support arms will cross the support arm after being extended. The positions of the fixing seats 20 intersect, for example, the first support arm 31 and the third support arm 41 will intersect after being extended, and the second support arm 32 and the fourth support arm 42 will intersect after being extended.

As shown in Figure 4, when the two supporting parts 30', 40' are parallel and the optical head reads the optical disc, the objective lens 50 will move as the disc rises and falls, so that the support arm holder 20 provides an The thrust and pull in the direction of the upper and lower support parts 30' and 40' will produce the rotation motion (Pitching) of tilting and steering, so that the objective lens will produce an inclination angle when it deviates from the steering (Yawing). Therefore, the support arm fixing seat 20 can also damp and suppress the high-frequency resonance frequency.

As shown in Figure 5, when the support arm fixing seat 20' has no elasticity, and when the optical read-write head reads the optical disc, the objective lens 50 will move with the up and down of the disc, thus causing the objective lens to be in a state of deviation from the steering (Yawing) inclination.

As shown in Figure 6, under the condition that the two supporting parts 30, 40 of the present utility model are not parallel to each other, and the supporting arm fixing base 20 has elasticity, the inclination angles of the above-mentioned objective lens in the two opposite directions of deviation from the steering (Yawing) will mutually offset each other. pin without producing objective lens tilt. In addition, the upper and lower supporting parts 30, 40 and the support arm fixing seat 20 can reduce the inclination angle of the objective lens 50 during low-frequency focusing movement, and the support arm fixing seat 20 can also damp and suppress the high-frequency resonance frequency.

Therefore, when the objective lens 50 performs low-frequency focusing, the optical read-write head objective lens carrying device can maintain the vibration mode in the focus direction, so that when the optical read-write head moves at low frequency, only the focus direction FD moves, and the suspension of the objective lens can also be increased. The rigidity of the device in the rolling direction. And when the objective lens 50 carries out high-frequency focusing, the optical read-write head objective lens carrying device can reduce the high-frequency resonance frequency, so as not to resonate with other components, and make the damping play the most effective, and the resonance mode without adverse effect appears at the high frequency domain.

According to the objective lens carrying device disclosed in the utility model, it includes the following effects:

1. The utility model uses the non-parallel upper and lower support parts and the elastic support arm fixing seat to prevent the objective lens from inclination when it deviates from the steering (Yawing).

2. The utility model moves the high-frequency resonance frequency to a suppressable frequency range through the elastic support arm fixing seat, so that it will not resonate with other components, and the damping can be maximized without adverse effects on the resonance The modes appear in the high-frequency domain to improve the stability of the optical read/write head when reading and writing.

The above are only preferred embodiments of the present utility model, and are not used to limit the scope of implementation of the present utility model; that is, all equal changes and modifications made according to the patent scope of the utility model are all the utility model. covered by the patent.

Claims (4)

1. An objective lens carrying device, used to carry an objective lens in the optical system of an optical pick-up head, the device includes: An objective lens frame has a through receiving hole for carrying the objective lens; A support arm holder, which has elasticity and is located at a fixed position relative to the optical axis of the objective lens; and An upper support part and a lower support part correspond to each other, and any one of the support parts has elasticity, one end is connected to the objective lens frame, and the other end is connected to the support arm fixing seat. After the two support parts are extended, they cross the support arm The positions of the mounts intersect. 2. The objective lens carrying device according to claim 1, wherein the upper and lower supporting parts respectively have a plurality of supporting arms parallel to each other, and each of the supporting arms corresponds to one supporting arm of another group, After the two corresponding to each other are extended, they intersect at the position beyond the support arm fixing seat. 3. The objective lens carrying device according to claim 1, wherein the support arm fixing base has a base and an elastic body, wherein the elastic body is arranged on one side of the base, and is connected with the upper and lower supporting parts connect. 4. The objective lens carrying device according to claim 3, wherein the elastic body is a thin plate.

Images