JPH0624015Y2 - Assembly of optical parts for optical head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of use) The present invention relates to an optical component assembly for an optical head, which is formed by combining a plurality of optical members constituting an optical head used for reading information from an optical disk. .

(Summary of the Invention) The present invention spreads an optical head assembly for an optical head including a laser light source element and a grating element, which are components of an optical head for emitting a laser beam, to a cylindrical portion and its surroundings. A holder member formed integrally with a mounting plate portion is provided, and a grating element is fixed to one end side of an internal hollow portion of the tubular portion in a position-regulated state, and a laser light source element is provided on the other end side. It is fixed in a position-regulated state, and further, a mounting plate-shaped portion of the holder member is provided with a mounting hole that allows the mounting plate-shaped portion to be rotatably adjustable with respect to the fixed portion. With a simple configuration with a small number of points, the laser light source element and the grating element in the optical head can be stably held appropriately, and the laser light source element and the grating element can be stably held. The position and orientation of the pointing element can be easily adjusted.

(Prior Art) In an optical disc player that reproduces recorded information from a disc used as an information recording medium, an optical system for reading recorded information from spiral or concentric recording tracks formed on the disc. Is provided.

In such an optical head device, for example, as shown in a simplified manner in FIG. 6, the entire device including the laser diode 1 and the photodetector 7 can be moved along the radial direction of the disk D. Then, the laser light beam emitted from the laser diode 1 is diffracted by the grating 2 into three laser light beams (in FIG. 6, these three laser light beams are represented by one solid line for simplification. (Shown by), the light beam passes through the polarization beam splitter 3 without changing its optical axis direction, and then enters the collimator lens 4. The three laser light beams that have entered the collimator lens 4 are collimated and enter the objective lens 5, and are converged by the objective lens 5 to reach the disc D, and a recording track formed on the disc D. Is reflected by the modulation at.

The reflected laser light beam from the disk D is reflected by the objective lens 5
After passing through the collimator lens 4 and returning, the optical axis direction is changed by the polarization beam splitter 3, it is guided to the photodetector 7 through the light receiving lens 6. Then, the detection output obtained from the photodetector 7 is supplied to a signal processing unit (not shown) to form a reproduction information signal, a focus control signal, a tracking control signal and the like. The focus control signal and tracking control signal are
Each of them is supplied to a focus control drive unit 8 and a tracking control drive unit 9 arranged in association with the objective lens 5, whereby the objective lens 5 is moved toward and away from the disc D along its optical axis. Drive operation for focus control is performed to move it to
A driving operation for tracking control is performed to move the objective lens 5 in the radial direction of the disc, which is the direction orthogonal to the optical axis.

In constructing such an optical head device, a block 1 including a laser diode 1 and a grating 2
At 0, the laser diode 1 is securely fixed, and the laser light beam incident from the laser diode 1 is adjusted so that the grating 2 can rotate and adjust the array surface of the three laser light beams obtained therefrom. It is required to be rotatably held around the optical axis of. In the conventionally proposed optical disc player, the block 10 including the laser diode 1 and the grating 2 is configured, for example, as shown in FIG.

In the configuration shown in FIG. 7, the cylindrical lens barrel 1
1 is used, and in the inner hollow portion of the lens barrel 11,
The grating holder 12 to which the grating 2 is fixed is disposed so as to abut on the annular stepped portion 11a provided on the lens barrel 11 from the inside, and further, the annular spacer 13 and the coil spring 14 are sequentially disposed, The laser diode 1 is inserted. Then, the holding plate member 15 is brought into contact with the end surface portion of the lens barrel 11 on the laser diode 1 side, and the set screw 16 is screwed into the screw hole 17 formed in the lens barrel 11, whereby the laser diode 1 is The lens barrel 11 is pressed and fixed to the annular step portion 11a side. In this way, the lens barrel 11 containing the laser diode 1 and the grating 2 is fixed to the optical head housing 18.

Based on such a configuration, the rotation adjustment of the grating 2 is
As shown in FIG. 8, the adjusting tool 20 inserted through the through hole 11b provided in the lens barrel 11 is engaged with the engaging groove 12a formed in the side surface of the grating holder 12 to which the grating 2 is fixed. The adjustment is performed by rotating the entire grating holder 12 in the direction of arrow G by the adjusting tool 20. After this rotation adjustment is made, the grating holder 12
Is fixed to the lens barrel 11 with an adhesive, for example.

(Problems to be Solved by the Invention) However, in the above-mentioned conventionally proposed holding mechanism for the laser diode 1 and the grating 2, the rotation adjustment of the grating 2 is performed by the grating arranged in the lens barrel 11. Since the holder 12 is rotated by the adjusting tool 20 inserted into the lens barrel 11 through the through hole 11b provided in the lens barrel 11, the adjustment work is difficult to perform and the holder 12 is relatively small. Since the grating holder 12 having the following dimensions is directly rotated, it is difficult to perform fine adjustment accurately.

In addition, the number of parts required to hold the laser diode 1 and the grating 2 is large, so that the assembly is troublesome and the cost is high.

In view of such a point, the present invention ensures that the laser light source element such as the laser diode and the grating element are held with an appropriate positional relationship based on a relatively simple configuration with a small number of parts. Moreover, it is an object of the present invention to provide an optical component assembly for an optical head, which is capable of easily adjusting the rotation of the grating element.

(Means for Solving the Problems) In order to achieve the above-mentioned object, in the optical component assembly for an optical head according to the present invention, a cylindrical portion and a mounting plate portion extending around the cylindrical portion are integrally made of a high thermal conductivity material. It is formed by molding, and the first and second ends are formed on one end side and the other end side of the inner hollow portion of the tubular portion.
And a holder member provided with mounting holes for allowing the mounting plate-shaped portion to be mounted to the fixing portion, and fixed to the first component storage mounting portion of the holder member. A grating element,
A laser light source element fixed to the second component housing attachment portion of the holder member and configured to cause laser light to enter the grating element through the inner hollow portion of the cylindrical portion of the holder member. The first and second component storage mounting portions provided on the tubular portion of the holder member have first and second position regulating surface portions, respectively, and the grating element has the first component storage mounting portion. The position of the laser light source element is regulated by the first position regulation surface portion, and the position of the laser light source element is regulated by the second position regulation surface portion of the second component housing attachment portion. Further, the mounting hole provided in the mounting plate-shaped portion of the holder member makes the mounting plate-shaped portion rotatable and adjustable with respect to the fixed portion.

(Operation) In the optical component assembly for the optical head according to the present invention configured as described above, the first component housing mounting portions of the grating element and the holder member are subjected to the position regulation by the first position regulating surface portion. And the laser light source element is fixed to the second component housing mounting portion of the holder member in a state of being regulated by the second position regulating surface portion, thereby facilitating easy mounting work. In addition, the laser light source element and the grating element are surely held in a proper positional relationship.
Then, the holder member in which the grating element and the laser light source element are respectively fixed to the first and second component housing attachment portions is attached to the fixing portion via the attachment holes provided in the attachment plate portion. At that time, the mounting plate-shaped portion can be rotationally adjusted with respect to the fixed portion, so that the entire holder member can be rotationally adjusted with respect to the fixed portion, and the grating element can be adjusted through rotational adjustment of the entire holder member. Since the rotation adjustment is performed and the grating element is not directly rotated, the delicate adjustment of the grating element can be accurately performed.

(Embodiment) FIGS. 1 and 2 are a sectional view and a plan view showing an example of an optical component assembly for an optical head according to the present invention. This example is, for example, the optical system shown in FIG. The block 10 including the laser diode 1 and the grating 2 in the head device is formed.

This example is configured to include a holder member 31 formed of a high thermal conductivity material such as a metal material, and a laser diode 1 and a grating 2 fixed to the holder member 31. The holder member 31 is made by, for example, zinc die casting, and as clearly shown in FIG. 3, a cylindrical tubular portion 32 and a mounting plate portion 33 extending around the tubular portion 32.
And are integrally molded. And the tubular portion 3
2 includes, on one end side of its internal hollow portion 34, a component storage mounting portion 35 for a grating having a rectangular plane contour.
And a component housing mounting portion 36 for a laser diode having a circular plane contour is provided on the other end side of the inner hollow portion 34, and the component housing mounting portion 35 for the grating is the inner hollow portion. 34 has a position regulating surface portion 35a that surrounds a part of one end side of 34, and the component housing mounting portion 36 for the laser diode also has a position regulating surface portion 36a that surrounds a part of the inner hollow portion 34 on the other end side. It is said that. Further, the peripheral wall end 36b of the component housing mounting portion 36 for the laser diode is
Is thinly formed, and the caulking portions 3 are provided at a plurality of locations.
6c is provided.

On the other hand, the mounting plate-shaped portion 33 of the holder member 31 is provided with a pair of mounting holes 37 at positions sandwiching the tubular portion 32,
As shown in FIG. 2, each of the mounting holes 37 is a long hole. Further, one end side of the mounting plate-shaped portion 33 is a bifurcated portion 38. Further, a pair of leg portions 39 are projected from a side edge portion of the attachment plate-shaped portion 33 from a position sandwiching the tubular portion 32 in a direction orthogonal to a direction connecting the pair of attachment holes 37.

For such a holder member 31, as shown in FIGS.
As shown in the figure, the rectangular grating 2 is housed and fixed in the component housing mounting portion 35 for the grating. At this time, the inside surface of the grating 2 is brought into contact with the position regulating surface portion 35a of the component accommodating attachment portion 35, and the position is regulated by the position regulating surface portion 35a. It is fixed to the mounting portion 35. Along with this, as shown in FIG. 1, the laser diode 1 is housed and fixed in the component housing mounting portion 36 for the laser diode. At this time, in the laser diode 1, the position regulation surface portion 3 of the component housing mounting portion 36 is provided at the peripheral portion of the upper surface of the base portion 1a.
6a, the position is regulated by the position regulating surface portion 36a, and the lower surface of the base portion 1a is provided on the peripheral wall end portion 36b of the component storage mounting portion 36 as shown in an enlarged view in FIG. By being caulked by the caulked portion 36c, it is fixed to the component storage mounting portion 36.

In this way, the laser diode 1 and the grating 2 are fixed to the holder member 31 under the condition that the position regulating surface portions 35a and 36a provided on the holder member 31 respectively regulate the position of the holder member 31. Therefore, it is surely held.

As shown in FIG. 5, the holder member 31 to which the laser diode 1 and the grating 2 are attached is further provided with a printed wiring board 40 on which other components are mounted as necessary, as shown in FIG. The pair of leg portions 39 projecting from is engaged and attached. At that time, each of the pair of leg portions 39 penetrates the through hole formed in the printed wiring board 40, and the tip thereof is the printed wiring board 4.
The printed wiring board 40 is fixed by being bent on the lower surface side of 0.

The holder member 31, which holds the laser diode 1 and the grating 2 and to which the printed wiring board 40 is attached as necessary, is a pair of holder members formed on the attachment plate portion 33 as shown in FIG. It is attached to a fixing portion 42 such as an optical head housing by a mounting screw 41 penetrating each mounting hole 37. At the time of such mounting, since the pair of mounting holes 37 formed in the mounting plate portion 33 are elongated holes, for example, as shown in FIG. 2, when the mounting screws 41 are temporarily tightened. Mounting plate part 3
With the adjuster 43 engaged with the bifurcated portion 38 forming one end of 3, the entire mounting plate portion 33, and hence the entire holder member 31, can be rotated in the direction along the arrow H. To be done. That is, the pair of mounting holes 37 formed in the mounting plate-shaped portion 33 are elongated holes, so that when mounting the mounting plate-shaped portion 33, the entire mounting plate-shaped portion 33, and hence the entire holder member 31. Is adjustable with respect to the fixed portion 42.

As described above, the entire holder member 31 is rotationally adjusted in the direction along the arrow H, so that the grating 2 held by the holder member 31 is rotationally adjusted with respect to the fixed portion 42. Such rotation adjustment of the grating 2 is performed without directly rotating the grating 2 and by placing the rotation acting position at a position separated from the grating 2 by charging and separating, so that the rotation acting position can be moved. As compared with this, the movement of the grating 2 is reduced, and therefore, fine rotation adjustment of the grating 2 can be accurately performed.

(Effects of the Invention) As is apparent from the above description, according to the optical member assembly for an optical head according to the present invention, the laser light source element such as a laser diode and the grating element, which are constituent elements of the optical head, have a reduced number of parts. With a relatively small and relatively simple structure and an easy mounting operation, it can be held in a state of being reliably held with an appropriate positional relationship. In addition, the rotation adjustment of the grating element is performed by rotating the holder member that holds the grating element without rotating the grating element directly, and thereby the grating element is rotated. The advantage that the delicate adjustment of the element can be accurately performed is obtained.

[Brief description of drawings]

1 is a sectional view showing an example of an optical member assembly for an optical head according to the present invention, FIG. 2 is a plan view of the example shown in FIG. 1,
3 is a sectional view of the holder member in the example shown in FIG. 1, FIG. 4 is a partially enlarged view of the example shown in FIG. 1, and FIG.
FIG. 1 is a side view showing a state in which other parts are attached to the example shown in FIG. 1, FIG. 6 is a schematic configuration diagram showing an example of an optical head, and FIG. 7 shows a conventionally proposed optical member assembly. FIG. 8 is an exploded view, and FIG. 8 is a sectional view provided for explaining the conventionally proposed optical member assembly shown in FIG. In the figure, 1 is a laser diode, 2 is a grating, and 3 is
1 is a holder member, 32 is a tubular part, 33 is a mounting plate part,
Reference numerals 35 and 36 are component storage attachment portions, 35a and 36a are position regulating surface portions, 36c is a caulking portion, and 37 is an attachment hole.

Claims (1)

[Scope of utility model registration request] 1. A tubular portion and a mounting plate portion that extends around the tubular portion are integrally formed of a high thermal conductivity material, and a first hollow portion is provided on one end side of an internal hollow portion of the tubular portion. A first component storage mounting portion having a position regulating surface portion is provided, and a second position regulating surface portion is provided on the other end side of the inner hollow portion of the tubular portion. A holder member provided with a component housing mounting portion, and further provided with a mounting hole for allowing the mounting plate-shaped portion to be rotatably adjustable with respect to the fixed portion, and the holder. A grating element fixed to the first component storage / attachment portion of the member in a state of being positionally regulated by the first position regulation surface portion; and a second element storage / attachment portion of the holder member on the second component storage / attachment portion. Depending on the position control surface of Is fixed in a state of being regulated, internal hollow section through an optical component assembling an optical head which is configured to include a laser light source device has been made as to be incident on the grating element in the tubular portion of the laser beam.