JPH02110984A - Device for adjusting optical axis of laser - Google Patents

Abstract

PURPOSE:To enable an adjusting operation to be very easily performed by a method wherein an irradiation point of laser rays is made to be coincident with a center axis at two parts whose lengths are different from each other, and the amount of adjustment is displayed basing on the computation of a deviation quantity of the irradiation point. CONSTITUTION:Laser rays flux 81 projected from a light projecting point 2' of a laser tube 2 is separated into light fluxes 81' and 81'' through a half mirror 7, where the light flux 81' half the flux 81 or so in volume travels straight and irradiates a first position detector 9 and the other light flux 81'' half the flux 81 or so in volume is reflected by the half mirror 7 and furthermore reflected two times by reflective film 10s to be a flux in parallel with optical axes 8 and 8', which irradiates a second position detector 11 the same as the flux 81'. Next, the totaled eight detected signals of eight photodetecting elements of the position detectors 9 and 11, which are provided with four photodetecting elements each, are separately amplified through an amplifier 14 and inputted into a computer 15. And, a required set condition is inputted through a set value input 16. As the result of the computation executes basing on the set values and the detected signals of the position detectors 9 and 11, the adjustment quantities of screw members 4 are shown on a display 17.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical axis adjustment device for a laser having a cylindrical outer tube.

(Prior art and its problems) Conventionally, a cylindrical outer tube 1 has been fitted at two locations (a, b) in the front and back, as shown in the front view of FIG.
It is necessary to adjust the optical axis of the laser tube 2, which is held at three points each (in two places), so that the optical axis of the laser beam is completely aligned with the central axis of the outer tube 1. .

In order to easily adjust the holding position of this laser at three points, one of the three points is a pressure member 3 that presses the laser tube 2 in the direction of the central axis of the outer tube 1 with a spring, and two points are the 1 each with a screw member 4 screwed onto the outer tube 1 in the direction of the central axis.
They are held at 20° intervals.

In order to adjust the optical axis 21 of the laser having such a structure,
As shown in FIG. 5, a position detector 22 for detecting the irradiation position is placed at the irradiation point of the laser beam 211, and the irradiation position is adjusted. This position detector 22, as shown in FIG. If the outputs of elements 13.13.13.13 are adjusted to be the same, the irradiation point 18 can be moved to the center point 1.
2 can be made to match.

However, with the above-mentioned adjustment method, although it is possible to irradiate the center point 12 at a certain distance after adjustment, it is not always clear whether or not the center point 12 will be irradiated at points at different distances. This means that even if the optical axis 21 is inclined with respect to the central axis, the irradiation point 18 at the above-mentioned constant distance is the central point 1.
Since the optical axis may be adjusted to 2, perfect optical axis adjustment is impossible.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide an optical axis adjustment device that can always align the optical axis with the central axis.

(Means for Achieving the Object) In order to achieve the above-mentioned object, the present invention provides a cylindrical outer tube 1
In a laser optical axis adjustment device having a laser tube 2 held at three points each at two places before and after the optical axis 8 of the laser beam,
The half mirror 7 provided above divides the system into two systems of first and second optical axes 8'' and 8'', and a first position detector 9 is placed above the first optical axis 8'', and a first position detector 9 is placed above the second optical axis. A second position detector 11 is provided on the optical axis 8'', and an optical system with different distances from the half mirror 7 to the first and second position detectors 9. It consists of a control system that calculates and displays the optical axis adjustment amount based on the detection signal of the second position detector 9.11, and a setting value input device 16 that inputs a setting value that is a condition for calculating the adjustment amount to the control system. , a calculator 15 that calculates the adjustment amount based on the input set value and the outputs of the first and second position detectors 9.11, and a display 17 that displays the calculation results of this calculator 15. It is equipped with.

(Function) As described above, in the adjustment device of the present invention, since the laser beam irradiation point 18 is made to coincide with the central axis at two different lengths, it is easy to make the optical axis 8 and the central axis coincide with each other completely. be.

Further, since the adjustment amount is calculated from the deviation amount of the irradiation point 18 and displayed, after the rough adjustment, fine adjustment can be made according to the display of the calculation result, and the adjustment work is extremely easy.

(Example) Fig. 1 shows a laser having a cylindrical outer tube whose optical axis can be adjusted by the optical axis adjusting device of the present invention, (A) is a front view, (B) is a side view (partially shown), FIG. 2 is an explanatory diagram of the optical system of the optical axis adjusting device of the present invention, and FIG. 3 is an explanatory diagram of the position detector of the irradiation point.

First, a laser that can be adjusted by this optical axis adjustment device will be explained. As shown in Figure 1 (a) and (b), the laser tube 2
1 at two places on the front and back so that it is coaxial with the cylindrical outer tube 1.
Three points are held at 20° intervals. These three points are held on a plane perpendicular to the central axis at two locations a and b at the front and rear of the laser tube 2, as shown in the same figure (b), and three points are located on a plane perpendicular to the central axis, as shown in
One of the points is held by a resilient member 3 that presses the outer tube 1 in the radial direction toward the central axis by a spring, and the other two points are held by a screw member 4 screwed into the outer tube 1. are held by pressing in the radial direction toward the central axis.

As a result, there are 4 laser tubes 2 in total, 2 each in the front and back.
By adjusting the screw members 4.4.4.4, the light projection point 2' can be adjusted to be on the central axis of the outer tube 1, and the optical axis 8 can also be made to coincide with the central axis.

In addition, although the laser tube 2 is directly held by the elastic member 3 and the screw member 4 in the above laser, an elastic member such as rubber is wrapped around the outer periphery of the laser tube 2, and the elastic member 3 and the screw member 4 are held by the elastic member. Of course, the structure for holding the laser tube 2 on the outside of the laser tube 2 may be one in which the laser tube 2 has earthquake resistance and shock resistance.

Next, the configuration of the optical system will be explained.

As shown in FIG. 2, the above-mentioned laser is mounted on two ``■'' shaped holders 6.6 fixed to the substrate 5 so as to be rotatable about the central axis.

On the optical axis 8 of this laser, a Hara mirror 7 fixed to a substrate 5 is fixed at an inclination angle of 45° with respect to the optical axis 8, and this optical axis 8 is designated as a straight first optical axis 8. It splits into a second optical axis 8'' which is reflected in the orthogonal direction.

The first optical axis 8' continues straight and reaches the first position detector 9 fixed to the substrate 5. The second optical axis 8'' is further reflected by two reflecting mirrors 10.10 to become parallel to the optical axis 8 and the first optical axis 8'', and is connected to a second position detector 11 fixed to the substrate 5. reach.

This is to make the passage distance of the second optical axis 8'' longer than that of the first optical axis 8''.

As shown in FIG. 3, the first and second position detectors 9.11 have four light-receiving elements 13.13.13 arranged at equal minute distances in two directions perpendicular to each other with the center point 12 of the light-receiving surface as the intersection point. .1
3 is the placement.

Next, the control system will be explained.

FIG. 4 is a circuit diagram of the control system. Four light receiving elements 13.13 of each of the first and second position detectors 9.11
．． A total of eight detection signals of 13.13 are amplified separately by an amplifier 14 and input to a calculator 15.

In addition to the above-mentioned detection signal, necessary setting conditions are input to the calculator 15 by the setting value input device 16. The setting conditions entered here are as follows.

1) Outer diameter d of the laser tube 2 (shown in Figure 2, same below) 2)
Distance between holding points of laser tube 2 (distance between a and b) j2t3)
l Distance 12 from alignment reference point a to first position detector 9
(Total length of optical axis 8 and first optical axis 8゛) 4) Adjustment reference point a
to the second position detector 11 (optical axis 8,
Total length of the second optical axis 8'') 5) Maximum permissible error range Based on the above settings and the detection signals of the position detectors 9 and 11, the calculation results of the calculator 15, that is, each screw member 4
．． The adjustment amount in 4.4.4 is displayed on the display 17.

Next, the operation of the above optical system will be explained.

a laser beam 8 projected from a laser tube 20 and a light projection point 2″;
By the half mirror 7, a luminous flux 8,' with approximately 1/2 light intensity is generated.
travels straight and irradiates the first position detector 9.

This irradiation point is indicated by 18. Other luminous flux 8 with approximately 1/2 light intensity
,” is reflected by the half mirror 7, and further reflected by the reflecting mirror 10.10
The light beam is reflected twice and is parallel to the optical axis 8.8゛.
The irradiation point 18 of the second position detector 11 is irradiated in the same manner as in step 1.

As a result, the lengths of the first optical axis 8'' and the second optical axis 8'' are different.

Next, the operation of the above adjustment device will be explained.

First, the outer tube 1 of the laser as shown in FIG. 1 is placed on the holder 6.6 as shown in FIG. 2, and the laser tube 2 is operated to generate a laser beam 81.

Next, the light beams B, + pass through the half mirror 7 and illuminate the light receiving surface of the first position detector 9, and the light beams 8,' pass through the half mirror 7.
7 and is separated from the light beam 311 and illuminates the light-receiving surface of the second position detector 11, so that the screw member 4.
Make rough adjustments in 4.4.4.

In this case, three points are held, but since one point is pressed in the direction of the central axis by a spring, the optical axis can be adjusted using screw members 4 in two directions.

In this state, on the light receiving surface of the position detector 9.11, if the irradiation point 18 of the luminous flux 81" or 81" comes to a position slightly shifted from the center point 12 as shown in FIG. The light receiving element 13.13.13.13 outputs a voltage corresponding to the amount of deviation of the irradiation point 18 as a detection signal.

These respective detection signals are separately amplified by an amplifier 14 and input to a calculator 15.

In this case, in order to correct deviations from the perfect circle due to manufacturing errors in the outer tube 1 and the laser tube 2, this input operation is performed four times by rotating the laser 90 degrees each on the central axis.

On the other hand, the calculator 15 has the setting conditions d, 2, ~
l8. Since the maximum allowable range has been input, the adjustment value is calculated based on each of the above input values, and the four screw members 4.
The adjustment amounts of 4.4.4 are individually displayed on the display 17.

This calculation operation is as follows.

1) Light receiving element 13.13.13 of each position detector 9.11
．． 13 and 13.13.13.13, each light receiving element 13 on each position detector 9.11 is compared.
The position of the irradiation point 18 is calculated using X-Y coordinates (the origin coincides with the center point 12), respectively. In this case, the position of the irradiation point in the X direction is calculated based on the output difference between the left and right pair of light receiving elements 13.13, and the position in the Y direction is calculated based on the output difference between the upper and lower pair of light receiving elements 13.13, and the position of the irradiation point 18 is calculated. Calculate.

2) On the first position detector 9, the position of the irradiation point 18 calculated in the previous section is set to have the same origin as the origin of the X-Y coordinates, and 1
Convert to 3-axis coordinates with 3 axes spaced at 20° intervals and adjust the adjustment amount α of the screw member 4.4 so that it comes to the origin (center point 12)
Calculate. The calculation in this case is performed using an assumed coefficient δ such that the light projection point 2'' is on the optical axis 8.

3) Similar calculations are performed for the second position adjuster 11 to calculate the adjustment amount β of the screw member 4.4. In this case, as in the previous section, the assumption count ε is used.

4) Compare the above α and β, and if there is a difference, change the above δ and ε and redo the calculation in Section 2.3.

5) As a result of the previous section, if the difference between α and β is within the set tolerance range, calculate the average value γ of the adjustment amounts α and β.

6) Perform the above calculation four times by rotating the laser 90 degrees as described above, calculate the average value of each γ, and display it on the display 17.
to be displayed.

According to the above-mentioned indication, by adjusting the four screw members 4.4.4.4 to their respective indications, the illumination points 18.18 on the first and second position detectors 9.11 can be set together. Adjustment can be made to the center point 12 or within a circle within its tolerance.

(Effects of the Invention) As described above, the luminous flux 81 obtained by decomposing the laser luminous flux 81
By aligning the irradiation points 18 of the ", 8" with the center points 12 of the first and second position detectors 9 and 11, it is possible to adjust the light flux to pass through the center points at different distances, so that the center line of the laser It is possible to easily match the light beam (optical axis) and the light beam (optical axis).

[Brief explanation of drawings]

Fig. 1 shows a laser having a cylindrical outer tube, (a) is a front view, (b) is a side view (partially), and Fig. 2 is an explanation of the optical system of the optical axis adjustment device of the present invention. 3 is an explanatory diagram of the position detector of the irradiation point, FIG. 4 is an explanatory diagram of the control system of the optical axis adjustment device of the present invention, and FIG. 5 is an explanatory diagram of the conventional optical system for optical axis adjustment. be. 1: Outer tube, 2: Laser tube, 7: Half mirror, 8:
Optical axis, 8゛: first optical axis, 8'': second optical axis, 9
: first position detector, 11: second position detector, 1
5: Calculator, 16: Setting value input device, Kiichimokukig! - 5th sticky note

Claims (1)

[Claims] In a laser optical axis adjustment device that has a laser tube held at three points each at two points in front and back of a cylindrical outer tube, two systems of first and second beams are adjusted by a half mirror installed on the optical axis of the laser beam. A first position detector is provided on the first optical axis, a second position detector is provided on the second optical axis, and the first and second position detection is performed from the half mirror. It consists of an optical system with different lengths to the instrument, and a control system that calculates and displays the amount of optical axis adjustment based on the outputs of the first and second position detectors. a set value input device for inputting a set value serving as a condition; a calculator for calculating an adjustment amount based on the input set value and the detection signals of the first and second position detectors; and a calculation result of this calculator. What is claimed is: 1. A laser optical axis adjustment device, comprising: a display that displays;