JP2003090938A - Optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily achieve automatization of an optical axis adjustment process in an optical device which performs optical axis adjustment of optical components. SOLUTION: An operation part 114 determines a first focal length from an image pick-up device 109 to a light emitting element 201 and a second focal length from the image pick-up device 109 to a lens 202 by controlling a movable part 103 which moves the image pick-up device 109 and a lens adjustment part 102 which moves the lens 202. The operation part 114 then determines a third focal length from the image pick-up device 109 to the image of the light emitting element 201 through the lens 202 in the state the lens 202 is placed in agreement with the central axis of the light emitting element 201, further determines the moving distance vertical to the central axis of the image pick-up device 109 when the focus is adjusted on the image of the light emitting element 202 by moving the lens 201 vertically to the central axis, and still further determines the fourth focal length of the lens 202 relative to the light emitting element 201 from the first to third focal lengths and the moving distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device, and more particularly to an optical device for adjusting an optical axis of an optical component incorporated in a package of an optical module.

[0002]

2. Description of the Related Art FIG. 23 shows the structure of a conventional LD (Laser Diode) module. A Peltier element 502 is provided in the LD package 501, and a base is placed on the Peltier element 502.
Put 503. A light emission output from the LD element 504 mounted on the base 503 is converted into a parallel beam 506 by a first lens 505 and input to an optical fiber 508 via a second lens 507.

FIG. 24 shows an optical device used for adjusting the optical axes of the LD element 504 and the first lens 505 shown in FIG. That is, this optical device uses an LD element (not shown) (corresponding to the LD element 504 in FIG. 23) as an LD.
It is installed on the element-equipped base 608 (corresponding to the base 503 in the same figure), and the optical axis is adjusted with the first lens 505 which is also not shown.

In this optical device, the base fixing portion 601 further fixes the LD element-equipped base 608 at the reference position. The LD element driving unit 602 sets the LD driving pin 609 to L
The LD element 504 is caused to emit light by bringing it into contact with the D element 504. The lens adjustment unit 603 includes a lens chuck 612 for fixing a lens holder 611 that holds the first lens 505, and a three-axis (X / Y / Z axis) fine movement table for lens adjustment.

The fiber adjustment unit 604 fixes the reference fiber 617, and adjusts the reference fiber 617 by four axes (X /
(Y / θ / φ axis) fine movement table. The reference adjustment unit 605 fixes the sensor head 616 of the optical power meter 615, and is provided with a biaxial (X / Y axis) fine movement table.

The light emission pattern confirmation section 606 includes an infrared camera 613 for detecting the light emission pattern and a monitor 614 connected to the infrared camera 613. Then, the laser welding portion 607 fixes the laser welding head 618, and the welding position is biaxial (Y / Z axis).
The position is adjusted by the fine movement table.

Next, the LD in the conventional LD package 501
A method of adjusting the element 504 and the first lens 505 will be described with reference to FIG. The LD element-equipped base 608 is fixed according to the reference surface of the base fixing portion 601. The LD driving pin 609 of the LD element driving unit 602 is provided with three axes (X / Y) on the upper side of the base 608 with the LD element.
/ Z axis) Move it on the fine movement table and bring it into contact with the LD element
A current is supplied to the element from the LD driving power supply 610 to cause the LD element to emit light.

A lens holder 611 including a lens is fixed by a chuck of a lens fixing portion 612, and a lens adjusting portion 603 is moved to a predetermined position by a triaxial (X / Y / Z axis) fine movement table. The two-axis (X / Y-axis) fine movement table of the lens adjustment unit 603 is used to roughly adjust the lens holder 611 so that the LD emission pattern comes to the center position of the infrared camera 613, and the beam emitted from this lens is made into a parallel beam. Operator to monitor 614
While observing the emission pattern displayed in, make a coarse adjustment with the 1-axis (Z-axis) fine movement table.

Further, the optical power meter 615 is moved along the optical axis by using the optical power meter sensor head 616,
The reference adjustment unit 605 is adjusted by a two-axis (X / Y-axis) fine movement table so that the detected optical power becomes maximum, and reference measurement is performed. Set the reference fiber 617 in the fiber adjustment unit 604 and set the four axes (X / Y / θ until the maximum output value is obtained.
/ Φ axis) Adjust with the fine motion table. After the adjustment is completed, the lens adjustment unit 603 (Z axis) and the fiber adjustment unit 604 (X / Y / θ / φ axis) are finely adjusted until the maximum output value is obtained, and the infrared camera 613 again outputs the LD emission pattern. Is in the center position. If there is misalignment, the lens adjustment unit 603
Move to the center position with (X / Y axis).

After that, the laser welding head 618 is moved to a predetermined position by a triaxial (X / Y / Z axis) fine movement table to weld the LD element base 608 and the lens holder 611. Next, the lens holder 611 is welded. In this way
Since the base 608 with the LD element on which the LD element and the lens are mounted is completed, the lens chuck 612 is removed, the current value of the LD element 504 is set to 0 mA, and the base 608 with the LD element is removed.

The base 608 with the LD element is shown in FIG.
The LD module is completed by using the base 503 shown in FIG.

[0012]

When the optical axis is adjusted by the above-mentioned method, it is necessary to confirm that the LD light emission pattern by the infrared camera is at the center position in order to make the emitted beam from the LD element a parallel beam. An adjustment process such as output confirmation with an optical power meter or a reference fiber is required, which complicates the adjustment process and increases man-hours.

Further, since such an adjusting process is performed manually, there is a problem that adjustment takes time and labor. Therefore, it is an object of the present invention to automate the optical axis adjustment process in an optical device that adjusts the optical axis of an optical component.

[0014]

In order to achieve the above object, an optical device according to the present invention comprises an image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, and a moving part of the lens. After obtaining the first focal length from the image pickup device to the light emitting element and the second focal length from the image pickup device to the lens, by controlling the lens adjusting part, the movable part and the lens adjusting part. , With the lens aligned with the central axis of the light emitting element, obtain a third focal length from the image pickup device to the image of the light emitting element through the lens, and move the lens by a predetermined distance perpendicular to the central axis. By obtaining the moving distance perpendicular to the central axis of the image pickup device when focusing on the image of the light emitting element, the fourth to fourth focal length of the lens with respect to the light emitting element from the first to third focal lengths and the moving distance. It is characterized by having a calculation unit for obtaining the focal length It is.

That is, in the present invention, the arithmetic unit controls the movable unit and the lens adjusting unit to execute the following arithmetic while moving the image pickup apparatus and the lens. First,
A first focal length from the image pickup device to the light emitting element is obtained, and then a second focal length from the image pickup device to the lens is obtained. Then, in a state in which the central axes of the lens and the light emitting element are aligned with each other, a third image from the imaging device to the light emitting element image passing through the lens is provided.
Find the focal length.

Further, the lens is moved by a predetermined distance in the direction perpendicular to the central axis to focus on the light emitting element image, and the moving distance of the image pickup device in the direction perpendicular to the central axis at this time is obtained. . Then, by using this movement distance and the first to third focal lengths, the fourth focal length between the light emitting element and the lens is obtained.

By thus obtaining the fourth focal length, if the position of the lens is adjusted to the fourth focal length, parallel light can be given from the lens to the image pickup device. Therefore, in obtaining parallel light, an adjustment process such as confirmation with an infrared light image or output confirmation with a reference fiber is unnecessary, and automation is possible, so that the optical axis adjustment time can be shortened ( Claim 1 / Appendix 1).

Further, the optical device according to the present invention includes an image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, a lens adjusting part for moving the lens, the movable part and the lens. By controlling the adjustment unit, the angle of the light emitting element with respect to the central axis of the light emitting element and the lens is obtained from the end face position of the light emitting element, and the first focal length from the imaging device to the light emitting element and the imaging After obtaining the second focal length from the device to the lens, the third focal length from the image pickup device to the light emitting element image passing through the lens is obtained while the lens is aligned with the central axis. By the second
When the first movement amount on the central axis from which the lens has moved from the focal length is obtained, and when the light emitting element image is focused by moving the lens by a predetermined distance perpendicular to the central axis The moving distance perpendicular to the central axis of the image pickup device is obtained, and the second moving distance perpendicular to the central axis moved by the lens from the time when the second focal length is obtained up to this time is obtained, and the angle, It can also be configured with a computing unit that obtains the fourth focal length of the lens with respect to the light emitting element from the first to third focal lengths, the first and second moving amounts, and the moving distances.

That is, in the present invention, the arithmetic unit controls the movable unit and the lens adjusting unit to execute the following arithmetic while moving the image pickup apparatus and the lens. First,
The angle of the light emitting element with respect to the central axis formed by the light emitting element and the lens is determined from the end face position of the light emitting element. Also, a first focal length from the image pickup device to the light emitting element is obtained, and then a second focal length from the image pickup device to the lens is obtained.

Then, the third focal length from the image pickup device to the image of the light emitting element passing through the lens is obtained with the central axes of the lens and the light emitting element aligned. On the other hand, the first amount of movement on the central axis by which the lens has moved is calculated from the time the second focal length is calculated to the time the third focal length is calculated.

Further, the lens is moved by a predetermined distance in the direction perpendicular to the central axis to focus the light emitting element image, and the moving distance of the image pickup device in the direction perpendicular to the central axis at this time is obtained. . On the other hand, a second amount of movement perpendicular to the central axis that the lens has moved is obtained from the time when the second focal length is obtained to the time when the movement distance is obtained.

Then, at this angle, the first to third focal lengths,
By using 1 and the second movement amount, and the movement distance,
A fourth focal length between the light emitting element and the lens is obtained. In this way, even when the direction of the light emitting element is tilted with respect to the central axis, the tilt amount can be corrected to obtain the fourth focal length, so the position of the lens can be adjusted to this fourth focal length. Then, parallel light can be given from the lens to the imaging device.

Therefore, in obtaining the parallel light, the adjusting process can be automated without considering the inclination of the light emitting element, and the optical axis adjusting time can be shortened (claim 2 / Appendix 2). . A laser welded portion for welding and fixing the lens at the position of the fourth focal length may be further provided (claim 3 / appendix 3).

In Claim 1 / Appendix 1, the first focal length is Z1, the second focal length is Z2, the third focal length is Z3, and the lens is moved perpendicularly to the central axis. The predetermined focal length is set to X3, and the moving distance perpendicular to the central axis of the image pickup device when the lens is moved by X3 to focus on the light emitting element image is set to X2. f can also be calculated as follows (Appendix
Four).

F = a × b / (a + b) Equation (1) where a = (Z1-Z3) / m Equation (2) b = Z1-Z3-a Equation (3) m = ((Z1 -Z3) / X3) / ((Z1-Z2) / X2) Formula (4) In Claim 2 / Appendix 2, the angle of the light emitting element with respect to the central axis is θ1, and the first focal length is Z1. And the second
The focal length is Z2, the third focal length is Z3, the first movement amount is Zr1-Zr2, the second movement amount is Xr5-Xr1, and the predetermined distance for moving the lens vertically to the central axis is .DELTA.Xr5. Then, the moving distance perpendicular to the central axis of the image pickup device when the light emitting element image is focused by moving the lens by ΔXr5 is ΔX3, and the fourth focal length f is as follows. It can also be calculated (Appendix 5).

[0026]   f = a × b / (a + b) Equation (5)   However, a = (Z1-Z3) / m ... Formula (6)         b = Z1−Z3−a Equation (7)         m = {((cos θ1 / (Zrα-Z1)) / (cosθ2 × ΔXr5))}         / {(Cos θ1 / (Z3−Z1) / (cos θ2 × ΔX3))} Equation (8)   However, θ2 = arctan (Xr5−Xr1) / Z2α Equation (9)         Zrα = (Z1-Z2)-(Zr1-Zr2) (10)         Z2α = Z2− (Zr1−Zr2) Equation (11)

[0027]

1 shows the structure of an embodiment of an optical device according to the present invention. In this embodiment, a base fixing portion 101, a lens adjusting portion 102 and a movable portion 103 are shown.
The laser welding section 104, the calculation section 114, and the vibration isolation table 115 for fixing them.

The base fixing portion 101 is for fixing the LD element-equipped base 105 in the same manner as in the conventional example of FIG. 24, and is a 1-axis (X-axis) automatic stage for adjusting the Z-axis coordinate between the LD element and the lens. I have it. Regarding the coordinate axes, the X axis is the vertical direction of the paper, the Y axis is the vertical direction of the paper, and the Z axis is the horizontal direction of the paper.

The lens adjustment unit 102 is provided with a lens chuck 107 for fixing a lens holder 106 including a lens (not shown), as in the conventional example shown in FIG. Equipped with a motorized stage (Y / Z axis). The movable unit 103 moves the CCD camera 109, and has three axes (X / Y / Z axes) for moving the CCD camera 109.
Equipped with a motorized stage. The CCD camera 109 acquires an image through the objective lens 108 attached to the tip.

The laser welding portion 104 is a laser welding head 113.
And is equipped with a two-axis (Y / Z-axis) automatic stage for moving the laser welding head 113 to the welding position. Then, the calculation unit 114 takes in the image obtained by the CCD camera 109 by the image processing unit 110, calculates the focus position and the like by the calculation processing unit 111 from this image, and the automatic stage controller 112 adjusts the lens by the focus position and the like. Part 10
2. The movable part 103 and the laser welded parts 104a and 104b are controlled.

An embodiment of the optical axis adjusting procedure of the optical device according to the present invention shown in FIG. 1 will be described below. Embodiment (1): FIGS. 2 to 11 First, an embodiment (1) of the optical axis adjusting procedure by the optical device shown in FIG. 1 when the end surface of the LD element has no angle will be described.

2 to 9 show the LD in this embodiment (1).
The arrangement of the element-equipped base 105 and the lens holder 106 is shown, and these procedures are described in accordance with the flowchart (steps S1 to 21) of the optical axis adjustment procedure executed by the calculation unit 114 shown in FIGS. Explain.

First, the LD element-equipped base 105 is fixed according to the reference surface of the base fixing portion 101 (step S1). The movable unit 103 is an automatic stage controller 112 of the calculation unit 114.
Output from the CCD camera 109 to the end surface 20 of the LD element 201.
It is moved to the initial position of 3 (step S2).

The movable section 103 further irradiates the visible light from the CCD camera 109 to the end surface 203 of the LD element so that the CCD camera 109
Is moved in units of several μm pitch on the Z axis. Arithmetic unit 11
4 recognizes the image of the LD element end surface 203,
The CCD camera 109 is moved by the automatic stage controller 112 and the movable part 103 to a position where the image data of (1) matches the image data prepared in advance, and the focus on the Z axis is adjusted (step S3).

Further, the movable portion 103 is, as shown in FIG.
Move the CD camera 109 on the X and Y axes to move the LD element end face 20
Image recognition of 3 and coordinate value of CCD camera 109 (X1, Y1)
Is read (step S4). The lens adjustment unit 102 fixes the lens holder 106 with the lens chuck 107, and under the control of the automatic stage controller 112, as shown in FIG. 3 (1), a predetermined position (Xr1, Yr
1, Zr1) (step S5).

The movable portion 103 is used by the CCD camera 109 for image recognition of the metal portion on the outer periphery of the lens.
The lens recognition position (X
(1, Y1, Z2) (step S6). movable part
103 is a lens 202 and a metal part 2 as shown in FIG.
Boundary part with 04 A (Xa, Ya), B (Xb, Yb),
The CCD camera 109 is moved on the X and Y axes to a position where C (Xc, Yc) is image-recognized and coincides with the image data prepared in advance, and the calculation unit 114 reads each coordinate value (steps S7 to 9). .

For image recognition, a method of performing pattern matching by using the normalized correlation value method shown in FIG. 3C to find a position where the degree of matching (correlation value) is maximum may be used. The movable unit 103 returns the CCD camera 109 to the above lens recognition position (X1, Y1, Z2) (step S1).
0). The calculation unit 114 moves the CCD camera 109 on the X and Y axes as described above, and thereby the boundary portion A
(Xa, Ya), B (Xb, Yb), C (Xc, Yc)
The lens center position (Xd, Yd) is calculated from the coordinate position of (step S11).

The lens adjusting unit 102 sets the center position (Xd, Yd) of the lens 202 to the center position (see FIG. 2) of the LD element end face 203 corresponding to the coordinates (X1, Y1) of the CCD camera 109 obtained in step S4. Lens holder 106 is moved as shown in FIG. 4 (step S12). The center coordinates of the lens 202 at this time are (Xr2, Yr2, Zr1).

Next, in order to enable the CCD camera 109 to recognize the image of the LD element end face 203 through the lens 202, the movable portion 103 first temporarily moves the CCD camera 109 by 3 mm on the Z axis as shown in FIG. It is moved and placed at the temporary position of coordinate Z3 (step S13). The lens adjusting unit 102 further moves the lens 202 on the Z axis as shown in FIG.
03 is image-recognized and moved to a position (Xr2, Yr2, Zr2) that matches the image data prepared in advance (step S14).

As a result, the image on the end surface 203 of the LD element can be recognized, but the output light from the lens 202 is not parallel light. Therefore, the lens adjustment unit 102 further moves the lens holder 106 on the X axis by a predetermined length (X3: 100 μm) as shown in FIG. 7 (step S1).
Five). As a result, the focal position of the LD element end surface 203 passing through the lens 202 also moves, so the computing unit 114 again recognizes the image of the LD element end surface 203 and reads the coordinate position (X2) on the X axis of the CCD camera 109. (Step S16), lens 20
The image magnification (m) of the LD element 201 over 2 is calculated (step S17).

The image magnification (m) in this case is, as shown in the above equation (4), the coordinate values Z1 to Z3 and the movement amount X2,
It can be calculated from X3. On the other hand, the focal length f of the lens 202 is given by the above equation (1), the parameters a and b in this equation (1) have the lengths shown in FIG. 8, and the above equation (2) and Given in (3).

Therefore, the focal length f can be obtained by using the equations (2) to (4). The lens adjustment unit 102 moves the lens holder 106 to the position of the focal length f calculated by the equation (1) (step S18). As a result, as shown in FIG.
The light emission output from the D element 201 passes through the lens 202, becomes parallel light, and is given to the CCD camera 109.

Then, the automatic stage controller 112
Moves the laser welding parts 104a and 104b fixing the laser welding head 113 to the welding position. Laser weld 10
The lens holder 106 is welded and fixed at 4a and 104b (step S19). After confirming the welding condition, if the welding is insufficient, perform the welding again in step S19.
If the element-equipped base 105 is in a defective state, the process ends as a defective product (step S20).

If welding is performed well, lens chuck
107 is removed and the base 105 with the LD element is removed (step S21). Embodiment (2): FIGS. 12 to 22 Next, an embodiment (2) of the optical axis adjusting procedure by the optical device shown in FIG. 1 when the LD element end face has an angle will be described. 12 to 20 show the arrangement of the LD element-equipped base 105 and the lens holder 106 in this embodiment (2), and these procedures are shown in FIG.
The procedure will be described with reference to the flowchart (steps S30 to 55) of the optical axis adjustment procedure executed in step 4.

First, the LD element-equipped base 105 is fixed to the reference surface of the base fixing portion 101 (step S30).
The movable part 103 is a CCD camera 109 as shown in FIG.
Is moved to the initial position for image recognition of the LD element 201 (step S31). The movable unit 103 is the CCD camera 1
Applying visible light from 09 to the end face 203 of the LD element, a few μ on the Z axis
It is moved in units of m pitches, and the focus (Ze) of the corner E of the LD element end face 203 on the Z axis is adjusted (step S32).

The movable portion 103 is, as shown in FIG.
The D camera 109 is moved on the X and Y axes to a position where the image data of the corner portion E of the LD element end surface 203 matches any one of a plurality of image data prepared in advance, and the LD element end surface 20 is moved.
3 is recognized as an image and the coordinate value (Xe, Y
e, Ze) is read (step S33).

Image recognition is performed in the same manner as in the embodiment (1).
A method may be used in which pattern matching is performed using the normalized correlation value method shown in FIG. 3C and a position at which the degree of matching (correlation value) is maximized is obtained. The movable portion 103 has a corner E
Similarly to the case of (3), the corner F of the LD element end face 203 is also focused (Zf) on the Z axis (step S34), and the coordinate values (Xf, Yf,
Zf) is read (step S35).

The calculation unit 114 calculates the angle and center position of the LD element 201. The angle θ1 is calculated by the following equation. θ1 = arctan ((Ze−Zf) / (Xe−Xf)) Equation (12) The movable portion 103 is focused on the center position (X1, Y1, Z1) of the LD element end face 203 as shown in FIG. Thus, the CCD camera 109 is moved (step S36).

The lens adjusting unit 102 fixes the lens holder 106 with the lens chuck 107, and as shown in FIG.
Predetermined position (Xr1, Yr1, Z on the base 105 with D element)
It is moved to r1) (step S37). In addition, the movable part 103
Moves the CCD camera 109 to the lens recognition position (X1, Y1, Z2) in the unit of several μm pitch on the Z-axis in order to image-recognize the metal portion 204 around the lens with the CCD camera 109 (step S38).

As shown in FIG. 2B, the movable portion 103 has a boundary portion A (Xa, Ya) between the lens 202 and the metal portion 204,
B (Xb, Yb) and C (Xc, Yc) are image-recognized and the CCD camera 109 is moved on the X- and Y-axes to a position that coincides with the image data prepared in advance, and the calculation unit 114 causes the coordinate value ( Z2) is read (steps S39-41).

Note that this image recognition may be performed in the same manner as in FIG. 3C in the embodiment (1). The calculation unit 114 moves the CCD camera 109 on the X and Y axes as described above, and thereby the boundary portions A (Xa, Ya) and B (Xb,
The lens center position (Xd, Yd) is calculated from the coordinate positions of Yb) and C (Xc, Yc) (step S42). The movable unit 103 returns the CCD camera 109 to the lens recognition position shown in the above step S38 (step S43).

The lens adjustment unit 102 moves the lens holder 106 to the center position (X1, Y1) of the LD element end surface 203 on the X and Y axes.
As shown in FIG. 15, the lens holder 106 is moved to X, Y so that the center position (Xd, Yd) of the lens 202 comes to (see FIG. 13).
It is moved along the axis (step S44). Lens at this time
The center coordinates of 202 are (Xr2, Yr2, Zr1).

In the movable part 103, the CCD camera 109 has a lens 20.
First, in order to recognize the image of the LD element end face 203 over two, first, FIG.
As shown in (3), it is temporarily moved by 3 mm on the Z axis and placed at a temporary position of coordinate Z3 (step S45). Next, as shown in FIG.
The movable unit 103 recognizes the image of the LD element end face 203 through the lens 202 in consideration of the inclination of the LD element 201. Therefore, first, the CCD camera 109 is moved on the X axis by ΔX2 (for example, −1047 μm). It is moved (step S46).

Then, the lens adjustment unit 102
Is moved by a movement amount ΔXr3 (for example, -388 μm) on the X axis as shown in the figure (step S47).
As shown in FIG. 18, the calculation unit 114 is moved on the Z axis.
Recognizes the image of the end face 203 of the LD element, and the coordinate position (Xr4, Yr2, Zr when it matches the image data prepared in advance)
2) is read (step S48).

As a result, the CCD camera 109 is the LD element 2
Although the end face image of 01 can be recognized, the output light from the lens 202 is not parallel light. Therefore, as shown in FIG. 19, the lens adjusting unit 102 further includes the lens holder 1
06 is moved on the X axis by a predetermined length .DELTA.Xr5 (for example, 100 .mu.m) (step S49). At this time, the lens center position coordinates are (Xr5, Yr2, Zr2).

As a result, the focal position of the LD element end surface 203 passing through the lens 202 also moves, so the computing unit 114 again
The CCD camera 109 is moved on the X axis by the amount ΔX3, and the LD element end face 203 is image-recognized.
The coordinate position (X3) on the X axis of the CD camera 109 is read (step S50), and the image magnification (m) of the LD element 201 passing through the lens 202 is calculated (step S51).

The image magnification (m) in this case is, as shown in the above equation (8), the coordinate values Z1 to Z3, Xr1 and Xr.
5, Zr1, Zr2, movement amounts X2, ΔX3, ΔXr5, and angle θ1 (equation (12)). On the other hand, the focal length f of the lens 202 is given by the above equation (5), and the parameters a and b in this equation (5) indicate the lengths shown in FIG. 8, and the above equation (6) And given in (7).

Therefore, the focal length f can be obtained by using the equations (6) to (11). The lens adjustment unit 102 moves the lens holder 106 to the position of the focal length f calculated by the equation (5). (Step S52). As a result, as shown in FIG. 20, the light emission output from the LD element 201 passes through the lens 202, becomes parallel light, and is given to the CCD camera 109.

Thereafter, steps S53 to S55 corresponding to steps S19 to S21 shown in FIG. 11 of the embodiment (1) are executed. (Supplementary Note 1) By controlling an image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, a lens adjustment part for moving the lens, and the movable part and the lens adjustment part, After obtaining the first focal length from the image pickup device to the light emitting element and the second focal length from the image pickup device to the lens, the image pickup device from the image pickup device with the lens aligned with the central axis of the light emitting device. The third focal length of the light emitting element image through the lens is determined, and the central axis of the image pickup device when the light emitting element image is focused by moving the lens by a predetermined distance perpendicular to the central axis Calculate the vertical movement distance
An optical device comprising: a first to third focal lengths and a calculation unit that obtains a fourth focal length of the lens with respect to the light emitting element from the moving distance.

(Supplementary Note 2) An image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, a lens adjusting part for moving the lens, and controlling the movable part and the lens adjusting part. The angle of the light emitting element with respect to the central axis formed by the light emitting element and the lens is obtained from the end face position of the light emitting element, and the first focal length from the imaging device to the light emitting element and the distance from the imaging device to the lens After determining the second focal length, determine the third focal length from the imaging device to the light emitting element image through the lens with the lens aligned with the central axis, From the time when the distance is obtained, the first movement amount on the central axis by which the lens is moved is obtained, and when the light emitting element image is focused by moving the lens by a predetermined distance perpendicularly to the central axis. Movement of the imaging device perpendicular to the central axis Obtains a second amount of movement perpendicular to the central axis of the lens is moved from the time of obtaining the second focal length by this time with obtaining the release, the angle, said 1
An optical device comprising: a third focal length, the first and second movement amounts, and a calculation unit that obtains a fourth focal length of the lens with respect to the light emitting element from the movement distance.

(Supplementary Note 3) The optical apparatus according to Supplementary Note 1 or 2, further comprising a laser welded portion for welding and fixing the lens at the position of the fourth focal length. (Supplementary Note 4) In Supplementary Note 1, the first focal length is Z1 and
The second focal length is Z2, the third focal length is Z3, a predetermined distance for moving the lens vertically to the central axis is X3, and the lens is moved by X3 to focus on the light emitting element image. An optical device, wherein a fourth focal length f is calculated as follows, where X2 is a movement distance perpendicular to the central axis of the image pickup device when the above are combined.

F = a × b / (a + b) Equation (1) where a = (Z1-Z3) / m Equation (2) b = Z1-Z3-a Equation (3) m = ((Z1 -Z3) / X3) / ((Z1−Z2) / X2) Equation (4) (Supplementary note 5) In Supplementary note 2, the angle of the light emitting element with respect to the central axis is θ1, and the first focal length is Z1. The second focal length is Z2, the third focal length is Z3, the first movement amount is Zr1-Zr2, the second movement amount is Xr5-Xr1, and the lens is moved vertically to the central axis. The distance is ΔXr
5 and the fourth focal length f when ΔX3 is the moving distance perpendicular to the central axis of the image pickup device when the light emitting element image is focused by moving the lens by ΔXr5.
Is calculated as follows.

[0063]   f = a × b / (a + b) Equation (5)   However, a = (Z1-Z3) / m ... Formula (6)         b = Z1−Z3−a Equation (7)         m = {((cos θ1 / (Zrα-Z1)) / (cosθ2 × ΔXr5))}         / {(Cos θ1 / (Z3−Z1) / (cos θ2 × ΔX3))} Equation (8)   However, θ2 = arctan (Xr5−Xr1) / Z2α Equation (9)         Zrα = (Z1-Z2)-(Zr1-Zr2) (10)         Z2α = Z2− (Zr1−Zr2) Equation (11)

[0064]

As described above, according to the optical device of the present invention, the arithmetic unit controls the movable unit for moving the image pickup device and the lens adjusting unit for moving the lens, so that the image pickup device emits light. After determining the first focal length to the element and the second focal length from the image pickup device to the lens, the third image from the image pickup device to the light emitting device image through the lens with the lens aligned with the central axis of the light emitting device. The focal length is obtained, the moving distance perpendicular to the central axis of the image pickup device when the lens is moved by a predetermined distance perpendicularly to the central axis and the light emitting element image is focused, and the first to third focal lengths are obtained. Since the fourth focal length of the lens with respect to the light emitting element is obtained from the moving distance, parallel light can be given from the lens to the image pickup apparatus by adjusting the position of the lens at the fourth focal length. Therefore, in obtaining parallel light, automation can be performed, and adjustment processes such as confirmation with an infrared light image and output confirmation with a reference fiber are unnecessary, and the optical axis adjustment time can be shortened. According to the experimental results, the adjustment time could be 5 minutes per piece.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration according to an embodiment of an optical device according to the present invention.

FIG. 2 is a schematic plan view showing an arrangement example at the time of recognizing an LD element end face in an embodiment (1) of an optical axis adjusting procedure by the optical device according to the present invention.

FIG. 3 is a schematic plan view showing an arrangement example at the time of recognizing a lens end face in the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 4 is a schematic plan view showing an arrangement example when the lens center position is moved in the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 5 is a schematic plan view showing an arrangement example when moving the position of the CCD camera Z axis in recognizing the LD element over the lens in the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention. is there.

FIG. 6 is a schematic plan view showing an arrangement example when moving the position of the lens Z axis in recognizing the LD element over the lens in the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention. .

FIG. 7 is a schematic plan view showing an arrangement example when calculating an image magnification in the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 8 is a schematic plan view showing an arrangement example when calculating a lens focal length.

FIG. 9 is a schematic plan view showing an arrangement example when a parallel beam is obtained by the embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 10 is a flowchart diagram (No. 1) showing an embodiment (1) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 11 is a flowchart diagram (No. 2) showing the embodiment (1) of the optical axis adjusting procedure by the optical device according to the present invention.

FIG. 12 is a schematic plan view showing an arrangement example at the time of calculating the LD element end face angle in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 13 is a schematic plan view showing an arrangement example at the time of recognizing an LD element end face in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 14 is a schematic plan view showing an arrangement example at the time of recognizing a lens end face in an example (2) of an optical axis adjusting procedure by the optical device according to the present invention.

FIG. 15 is a schematic plan view showing an arrangement example when the lens center position is moved in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 16 is a schematic plan view showing an arrangement example when moving the position of the CCD camera Z-axis in recognizing the LD element passing through the lens in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention. is there.

FIG. 17 is a schematic plan view showing an arrangement example in the case of recognizing an LD element passing through a lens in an embodiment (2) of an optical axis adjustment procedure by the optical device according to the present invention, when correcting the LD element angle.

FIG. 18 is a schematic plan view showing an arrangement example in the case of moving the position of the lens Z axis in recognizing the LD element over the lens in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention. .

FIG. 19 is a schematic plan view showing an arrangement example at the time of calculating the image magnification in the embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 20 is a schematic plan view showing an arrangement example when a parallel beam is obtained by the example (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 21 is a flowchart diagram (part 1) showing an embodiment (2) of the optical axis adjustment procedure by the optical device according to the present invention.

FIG. 22 is a flowchart diagram (No. 2) showing the embodiment (2) of the optical axis adjusting procedure by the optical device according to the present invention.

FIG. 23 is a diagram showing a structure of a conventional LD module.

FIG. 24 is a perspective view showing a configuration of a conventional optical device.

[Explanation of symbols]

101 Base fixing part 102 Lens adjusting part 103 Movable part 104a, 10
4b Laser welding part 105 Base with LD element 106 Lens holder 107 Lens chuck 108 Objective lens 109 CCD camera 110 Image processing part 111 Arithmetic processing part 112 Auto stage controller 113 Laser welding head 114 Arithmetic part 115 Vibration isolation table 201 LD
Element 202 lens 501 LD
Package 502 Peltier element 503 Base 504 LD element 505 First lens 506 Parallel lens 507 Second lens 508 Optical fiber 601 Base fixing part 602 LD element driving part 603 Lens adjusting part 604 Fiber adjusting part 605 Reference adjusting part 606 Light emitting pattern checking part 607 Laser weld 608 LD element base 609 LD
Drive pin 610 LD drive power supply 611 Lens / lens holder 612 Lens chuck 613 Infrared camera 614 Monitor 615 Optical power meter 616 Optical power meter sensor head 617 Reference fiber 618 Laser welding head 619 Vibration isolator A considerable part is shown.

Continued front page    F-term (reference) 2H037 BA03 BA11 DA03 DA05 DA22                 2H044 AC01                 5F073 AB27 AB28 FA25

Claims (3)

[Claims] 1. An image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, a lens adjusting part for moving the lens, and a movable part and the lens adjusting part are controlled, After obtaining the first focal length from the image pickup device to the light emitting element and the second focal length from the image pickup device to the lens, the lens is aligned with the central axis of the light emitting device from the image pickup device. The central axis of the image pickup device when the third focal length of the light emitting element image through the lens is obtained and the light emitting element image is focused by moving the lens by a predetermined distance perpendicular to the central axis. A moving distance perpendicular to the first to third focal lengths and the moving distance, and
4 An optical device comprising: a calculation unit for obtaining a focal length; 2. An image pickup device, a light emitting element, a lens, a movable part for moving the image pickup device, a lens adjusting part for moving the lens, and a movable part and the lens adjusting part for controlling, The angle of the light emitting element with respect to the central axis formed by the light emitting element and the lens is determined from the end face position of the light emitting element, and the first focal length from the imaging device to the light emitting element and the second focal length from the imaging device to the lens After obtaining the focal length, the third focal length from the image pickup device to the light emitting element image passing through the lens is obtained while the lens is aligned with the central axis, and the second focal length is set by this time. The image pickup device when the light-emitting element image is focused by obtaining a first movement amount on the central axis by which the lens has moved from the obtained time and moving the lens by a predetermined distance perpendicularly to the central axis. Find the distance traveled perpendicular to the central axis of Along with this time, the second movement amount perpendicular to the center axis from which the lens has moved is obtained from the time when the second focal length is obtained, and the angle, the first to third focal lengths, the first and No. 2
An optical device comprising: a calculation unit that obtains a fourth focal length of the lens with respect to the light emitting element based on a movement amount and the movement distance. 3. The optical device according to claim 1, further comprising a laser welded portion for welding and fixing the lens at a position of the fourth focal length.