JP2001155378A - Method and device for assembling optical pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the arrangement of a device optical system and a detecting method for adjusting a unit composed of light emission and receiving elements and a hologram, and to simply and accurately assemble a pickup device, in a method and a device for assembling the optical pickup device. SOLUTION: This device is provided with a collimator lens for receiving a luminous flux from a unit composed of light emission and receiving elements and a hologram, and a half mirror and an auto-collimator for receiving parallel lights from the collimator lens. The half mirror and the auto-collimator are placed oppositely to each other to make a pair, and capable of making a shifting adjustment for the luminous flux. While the parallel light adjustment of the collimator lens and the shifting adjustment of the half mirror are made based on the information of the auto-collimator, the relative positions of the light receiving element and the hologram are adjusted with the luminous flux from the light emission element set as a reference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for assembling an optical pickup device in a simple and accurate manner, and is applicable to the assembly of fine parts.

[0002]

2. Description of the Related Art As a conventional optical pickup adjusting method,
For example, those described in JP-A-8-111026 can be mentioned. This includes a light emitting element, a light receiving element that receives reflected light of irradiation light from the light emitting element, a collimator lens that makes the emitted light parallel, an anti-slope surface that reflects irradiation light from the light emitting element, An objective lens for condensing the irradiation light from the element on the anti-slope surface, and an optical element (diffraction grating and hologram) for applying the irradiation light from the light-emitting element to the objective lens and providing the reflection light from the anti-slope surface to the light receiving element. This is a method for adjusting the provided optical pickup. Under this configuration, the collimator lens creates ideal parallel light, creates a state where the focal point of the objective lens coincides with the anti-slope surface, the light receiving intensity of the light receiving element at this time becomes maximum, and the objective lens is moved along the optical axis. The optical element (diffraction grating and hologram) is rotated about the optical axis so that the received light intensity when moved by + L and -L in the direction becomes equal. However, it is very difficult to adjust the position of the ideal parallel light or focus, and a detection system for the adjustment is required separately when actually performing the adjustment.

In recent years, among components constituting an optical pickup device, a light-emitting element, a hologram, and a light-receiving element are unitized (packaged) and adjusted and assembled in advance to form one component. Attempts have been made to simplify assembly adjustments. In the above unit, since the required accuracy of the relative position between the light emitting element, the hologram, and the light receiving element is high, as an adjustment method, an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device is used. It is conceivable to prepare as an equipment-side optical system and to assemble and adjust based on the light of the light emitting element in the unit.

However, the above-mentioned prior art does not assume the adjustment of the unitized components, and the adjustment and assembly of the equipment-side optical system effective for such adjustment and the pickup device have been performed with high accuracy. No effective method or apparatus has been proposed.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention proposes a configuration of an equipment optical system and a detection method for adjusting a unit composed of a light emitting element, a light receiving element, and a hologram, thereby simplifying the assembly of a pickup device. The task is to do well.

[0006]

Means taken to solve the problem are a collimator lens receiving a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, and a half mirror receiving parallel light from the lens. The auto-collimator has a half mirror and an auto-collimator that can be tilted and adjusted for the luminous flux as a pair while facing each other, and adjusts the parallel light of the collimator lens and the tilt of the half mirror from the information of the auto-collimator. In this state, the relative positions of the light receiving element and the hologram are adjusted based on the light flux from the light emitting element. Also, a collimator lens that receives a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, an objective lens that receives parallel light from the lens, a half mirror that receives a spot focused by the objective lens, and a collimator lens Means for detecting parallel light in each of the forward and backward paths between the lens and the objective lens, and a collimator lens and an objective lens having a movable mechanism in the focal direction, and operating the collimator lens and the objective lens based on information from the parallel light detection means. With the parallel light adjustment performed, the relative positions of the light receiving element and the hologram are adjusted based on the light flux from the light emitting element. Further, the double knife edge method is used as the parallel light adjusting means. In addition, two parallel plates arranged at a predetermined angle in a light beam to be adjusted to parallel light are installed as parallel light adjusting means, and interference fringes of the light beam are measured. Also, the relative positioning of the light receiving element and the hologram is roughly adjusted from the image processing information of the CCD camera capable of recognizing the position and orientation of the light receiving element, the light emitting element, and the hologram. Relative positioning was performed by fine adjustment.

[0007]

[Function] Since parallel light adjustment of the collimator lens and tilt adjustment of the half mirror are performed based on the information of the autocollimator, an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device can be achieved with high accuracy. The relative positions of the light receiving element and the hologram can be adjusted based on the light flux from the light emitting element. In addition, a parallel light detecting means is provided, and the collimator lens and the objective lens are operated based on the information to adjust the parallel light, so that the optical system that is equivalent to or has the same effect as the optical system of the optical pickup device is accurately obtained. This can be achieved well, and the relative positions of the light receiving element and the hologram can be adjusted based on the light flux from the light emitting element. Further, by using the double knife edge method, the parallel light can be adjusted with high accuracy. Further, since two flat plates are provided in the light beam and the interference fringes of the light beam are measured, the parallel light can be adjusted with high accuracy. Also,
Since the relative position adjustment of the light emitting element, the light receiving element, and the hologram is performed separately for the coarse adjustment and the fine adjustment, the adjustment time is shortened and the accuracy is improved.

[0008]

FIG. 1 shows an embodiment of an optical pickup assembling apparatus. 1 is a light emitting element (LD), 2 is a light receiving element (PD) and 3 is a hologram (HOE), and these components constitute one unit. In this case, the light emitting element 1 and the hologram 3 are assembled with respect to the reference surface of the unit housing 4, and the position of the light receiving element 2 is adjusted based on the light of the light emitting element 1. Depending on the configuration of the unit, a prism (mirror) 5 may be provided as shown in the figure.

The equipment side optical system 10 has a collimator lens 6 for receiving a light beam from the unit, a half mirror 7 for receiving parallel light from the lens, and an autocollimator 8. The half mirror 7 and the autocollimator 8 are adjusted so as to face each other, and then a stage 9 having an α axis (a rotation axis around the X axis) and a β axis (a rotation axis around the Y axis).
To be mounted on. According to this configuration, the tilt adjustment of the stage 9 can be performed by the facility-side optical system movable mechanism 12 such that the half mirror 7 and the autocollimator 8 are paired and the anti-slope surface is perpendicular to the optical axis.

The adjustment of the equipment-side optical system 10 is performed by
Due to variations in the hologram 3, the unit housing 4, and the like, it is necessary to adjust the parallel light of the collimator lens 6 and adjust the tilt of the half mirror 7 each time it is assembled. The autocollimator 8 is used as a detection system for these two types of adjustment.

In the parallel light adjustment, the position of the collimator lens 6 is adjusted in the optical axis direction so that the spot reflected on the autocollimator 8 is minimized. As shown in FIG. 2, the tilt adjustment is performed by a pair of the half mirror 7 and the autocollimator 8 so that the position of the spot reflected on the autocollimator 8 is centered. By performing this adjustment, an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device can be achieved. When performing this adjustment automatically, as shown in FIG.
11 and image processing is performed.

After the adjustment of the equipment-side optical system 10, the position of the light receiving element 2 is adjusted by the light receiving element moving mechanism 13. FIG.
The adjustment is performed so that the spot is located at an appropriate position as shown in (2), and the assembly of the unit is completed. The spot on the dividing line is for focusing, and the other two points are for tracking. This position adjustment is performed by calculating the light amount of the light receiving element 2.

Further, the adjustment of the light receiving element 2 is divided into two of coarse and fine adjustment, and the coarse adjustment is performed based on image processing information by a CCD (not shown), and then the above adjustment (fine adjustment) is performed. Good.

FIG. 4 shows another embodiment. The prerequisites for assembling the units are the same as in the above-described embodiment. The equipment-side optical system 30 includes a collimator lens 26 that receives a light beam from the unit and an objective lens 2 that receives parallel light from the lens.
And a half mirror 27 for receiving the spot focused by the objective lens 29, means 31 for detecting parallel light in each of the forward and backward paths between the collimator lens 26 and the objective lens 29, the collimator lens 26 and the objective Equipment-side optical system movable mechanism 3 in focal direction (optical axis direction) on lens 29
2 According to this, it is possible to achieve an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device in a pseudo manner only by adjusting the parallel light. The half mirror 27 plays the same role as the disk of the pickup device,
Since the light is reflected at the focal position, it may be installed substantially vertically.

As a means for detecting and adjusting the parallel light, for example, a double knife edge method may be used. Alternatively, two flat plates may be arranged at a predetermined angle in the light beam to be adjusted to parallel light, and the light beams separated by these flat plates may interfere with each other, and the interference fringes may be measured and adjusted.

Based on the information from the parallel light detecting means 31, the collimator lens 26 and the objective lens 29 are operated to adjust the parallel light, and the position of the light receiving element 22 is determined based on the light beam from the light emitting element 21. After adjustment, unit assembly is completed.

Also in this embodiment, the adjustment of the light receiving element 22 may be divided into two, that is, coarse adjustment and fine adjustment, and the coarse adjustment may be performed based on image processing information by the CCD 34, and then the fine adjustment may be performed.

[0018]

The parallel light adjustment of the collimator lens and the tilt adjustment of the half mirror are performed based on the information of the autocollimator, so that an optical system which is equivalent to or has the same effect as the optical system of the optical pickup device is simplified. In this state, the relative position of the light receiving element and the hologram is adjusted based on the light flux from the light emitting element. Therefore, even a unit that requires high-precision positioning can accurately receive light based on the light flux from the light emitting point. The position of the element can be adjusted. In addition, since the position of the collimator lens and the objective lens is adjusted based on the information of the parallel light detecting means and the parallel light is adjusted, an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device is simple and quick. Can be achieved. In this state, since the relative positions of the light receiving element and the hologram can be adjusted based on the light flux from the light emitting element, the position of the light receiving element can be accurately adjusted even with a single unit, based on the light flux from the light emitting point. Further, since the double knife edge method is used as the parallel light adjusting means, parallel light adjustment can be performed with high accuracy, and an optical system that is equivalent to or has the same effect as the optical system of the optical pickup device can be achieved quickly and accurately. Moreover, since the parallel light adjusting means measures the interference fringes of the light beam separated by the two flat plates, the parallel light can be adjusted with high accuracy, and is equivalent to or has the same effect as the optical system of the optical pickup device. Can be quickly and accurately achieved. In addition, since the relative position adjustment of the light emitting element, the light receiving element, and the hologram is separately performed for the coarse adjustment and the fine adjustment, the adjustment time is shortened and the positioning accuracy is improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an adjustment device for assembling an optical pickup.

FIG. 2 is a diagram showing a half mirror tilt adjustment method.

FIG. 3 is a diagram showing a positional relationship between a light receiving element and a spot.

FIG. 4 is a schematic configuration diagram of an adjusting device according to another embodiment. Description of the reference numerals in FIGS. 1 to 4 1,21... Light emitting element 2,22... Light receiving element 3. Hologram 4, 24 Unit housing 5, 25 Prism (mirror) 6, 26 Collimator lens 7, 27 ········· Half mirror 8 ····· Autocollimator 9 ··· Stage 10 and 30 ········ Equipment side optical system 11 ・ ・ ・ CCD 12, 32 ・ ・ ・ ・ ・ ・ ・ ・ ・ Equipment side optical system movable mechanism 13, 33 ・ ・ ・ ・ ・ ・ ・ ・ ・ Light receiving element movable mechanism 31 ... Parallel light detection means 34 CCD for coarse adjustment

Claims (10)

[Claims] 1. A collimator lens for receiving a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, a half mirror for receiving parallel light from the lens, and an autocollimator, wherein the half mirror and the autocollimator face each other. In a state where the light beam can be adjusted as a pair in a state, the parallel light adjustment of the collimator lens and the tilt adjustment of the half mirror have been performed based on the information of the autocollimator, and the light receiving element and hologram based on the light beam from the light emitting element. Adjusting the relative position of the optical pickup device. 2. A collimator lens for receiving a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, an objective lens for receiving parallel light from the lens, and a half mirror for receiving a spot focused by the objective lens. ,
The collimator lens and the objective lens have means for detecting parallel light in each of the forward and backward paths, and the collimator lens and the objective lens have a movable mechanism in the focal direction, and the collimator lens and the objective lens are provided with information from the parallel light detection means. A method for assembling an optical pickup device, comprising adjusting a relative position of a light receiving element and a hologram with reference to a light beam from a light emitting element while operating and adjusting parallel light. 3. The method of assembling an optical pickup device according to claim 2, wherein a double knife edge method is used as the parallel light adjusting means. 4. A method for assembling an optical pickup device according to claim 2, wherein two parallel flat plates arranged at a predetermined angle in a light beam to be adjusted to parallel light are installed as parallel light adjusting means. A method for assembling an optical pickup device, comprising measuring interference fringes of the light beam. 5. A light receiving element, a light emitting element, and relative positioning of the light receiving element and the hologram are roughly adjusted from image processing information of a CCD camera capable of recognizing the position and orientation of the hologram. 5. The method for assembling an optical pickup device according to claim 1, wherein relative positioning of the hologram and the hologram is performed by fine adjustment. 6. A collimator lens for receiving a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, a half mirror for receiving parallel light from the lens, and an autocollimator, wherein the half mirror and the autocollimator face each other. In a state where the light beam can be adjusted as a pair in a state, the parallel light adjustment of the collimator lens and the tilt adjustment of the half mirror have been performed based on the information of the autocollimator, and the light receiving element and hologram based on the light beam from the light emitting element. An optical pickup device for adjusting the relative position of the optical pickup device. 7. A collimator lens for receiving a light beam from a unit composed of a light emitting element, a light receiving element, and a hologram, an objective lens for receiving parallel light from the lens, and a half mirror for receiving a spot focused by the objective lens. ,
The collimator lens and the objective lens have means for detecting parallel light in each of the forward and backward paths, and the collimator lens and the objective lens have a movable mechanism in the focal direction, and the collimator lens and the objective lens are provided with information from the parallel light detection means. An apparatus for assembling an optical pickup device, wherein the relative positions of a light receiving element and a hologram are adjusted based on a light beam from a light emitting element while operating to adjust parallel light. 8. The apparatus for assembling an optical pickup device according to claim 7, wherein a double knife edge method is used as the parallel light adjusting means. 9. An apparatus for assembling an optical pickup device according to claim 7, wherein two parallel flat plates arranged at a predetermined angle in a light beam to be adjusted to parallel light are installed as parallel light adjusting means. An apparatus for assembling an optical pickup device, wherein interference fringes of the light beam are measured. 10. A light receiving element, a light emitting element, and relative positioning of the light receiving element and the hologram are roughly adjusted from image processing information of a CCD camera capable of recognizing the position and orientation of the hologram. 9. The relative positioning of the hologram and the hologram is performed by fine adjustment.
Optical pickup device assembly equipment.