JPS58135788A - Laser machining device - Google Patents

Abstract

PURPOSE:To machine the work by laser fully automatically and stably by converting the power of the laser light to be irradiated to the work to an electrical signal, inputting the same to a control device and maintaining the operated value of power density at a desired value. CONSTITUTION:A laser oscillator 1 is turned on to generate laser light 2 by the signal from a control device 22 in which information on machining conditions is stored. A shuter 21 is held closed in this stage so that the laser light 2 reflected by a dichroic mirror 3' is not irradiated to the work 7. The laser light transmitted through the mirror 3' in this state is irradiated to a photodetector 15 through a rectangular aperture slit 16 for measurement and an interference filter 20. The detector 15 inputs the electric signal corresponding to the power of the light 2 to the device 22. The device 22 operates the actual power to be irradiated to the work 7 from said electric signal and controls the transmittivity of a variable transmittance filter 18 so as to make the same coincident with the stored power density. The shutter 21 is then opened automatically by the device 22.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of an aperture projection type Rade processing device, which makes it possible to automatically adjust the /99W density of the Rade light either before or during laser processing. . This invention relates to laser processing equipment.

Radical processing using the aperture projection method is performed by irradiating the processed portion of the workpiece with a laser beam of the same laser density.

Therefore, when the area of the processed part changes, the dimensions of the opening through which the laser beam passes are changed accordingly, and the arm V! is constant over the entire surface of the processed part. It is necessary to operate the device so that the irradiation is performed at a certain degree.

Also, 9W density is expressed by the amount of laser light per unit aperture area ρ, so 2. Of course, if the opening area changes, the arm ff
The i degree will also change.

Conventional power density 111141 was performed as follows. That is, the aperture slit is adjusted and set in order to determine the irradiation range that matches the processing area of the workpiece. Next, the workpiece is mounted, the nine tables are moved, and the position is adjusted so that the Raded light irradiated to the processed part enters the light detection part of the photodetector.After death, the Raded light is irradiated. The f-war of the Raded light is measured by a photodetector, and this is divided by the aperture slit area to obtain the arm density. It was adjusted by changing the voltage or excitation current.

Furthermore, these adjustments have been made manually through the observation optical system. As a result, it takes a lot of time to set the 9W density, and in addition, it is difficult to tell even if the laser beam changes during laser processing, resulting in uneven processing. Nine.

This conventional radar processing apparatus is shown in FIG. 1 and will be described in more detail.

In the figure, Rade light 2 oscillated from Rade oscillator 1
, the party strategy was distorted by Gikroic Mirror 3,
The radar light is guided through the rectangular opening slit 4 and its passage is restricted. □The nine led lights passing through this rectangular aperture slit 4 become a luminous flux having the shape of the rectangular aperture slit 4,
The light passes through the nof mirror 5, is focused by the objective lens 6, and is irradiated onto the workpiece 7.

Here, the workpiece 7 and the rectangular slit 4 are
The aperture of the objective lens 6 is determined by the objective lens 6.
The positional relationship is such that the image is projected while being reduced to the size of the reciprocal of the magnification MO (1/M).

To observe and align the workpiece 7, the light from the illumination light gI9 is combined with the half mirror 5 and lO, and the observation optical system 11
It is supposed to be done through. Note that 12 is a radar cut filter, which is provided in a round shape to ensure the safety of the observer. Reference numeral 13 denotes a slit illumination light source, which transmits through the gicroic mirror 3 and is projected onto the workpiece 7 by the objective lens 6 as a projected image of the rectangular aperture slit 4.
I will be taken away.

Here, the guichroic mirror 3 has a characteristic of reflecting 20 wavelengths of Radhe light and transmitting a specific wavelength of the slit illumination light 3. The rectangular opening slit 4 caused by the slit illumination light 3 can also be observed by the observation system 11.

When performing the radar processing using the conventional radar processing apparatus configured as described above, the following procedure is used.

First, IIK, the irradiation range of the Raded light 2 to be irradiated onto the workpiece 7 is set by operating the drive device 14 and moving the rectangular opening slit 4 .

Next, the CX-Y table 17 is moved, and the projected image of the rectangular aperture slit by the slit illumination light on the workpiece 7, which is reduced and projected by the objective lens 6, completely enters the photodetector part of the photodetector 15. Adjust as follows. In this case, since it is not possible to irradiate the Raded light 2 for 1 m before performing Raded processing, the X-Y tape A = 17 is moved between do.

After the above adjustment is completed, the laser beam 2 is emitted from the radar oscillator 1, and the laser beam 2 is transmitted through the objective lens 6.
9 hours are read by the hour meter 16.

Calculate the power density by dividing the 20 mm of light obtained in this way by the area of the 9 apertures formed by the rectangular aperture slit 4. If the density differs from the desired value, adjust the excitation voltage or current of the two-laser oscillator 1, or continuously adjust the transmittance of the laser beam. By operating the variable transmittance filter 18, the I value of the Led light is changed, and the value is measured by the NOWER meter 16 and divided, and the desired light density value and 9 of the Led light actually irradiated are calculated.
Repeat the following operations over and over again until the arm density matches the arm and arm density.

After the quantity density is adjusted in this way, the X-Y table 17 is moved to align the workpiece 7 while observing the rectangular aperture projected image by the slit illumination light 3 using the observation optical system 11. After this, the laser oscillator 1 oscillates the Raded light 2 to perform the Raded processing. The above-mentioned complicated operations cannot be performed during laser processing, and even if the wafer density changes during laser processing, the laser processing will continue as is.

SUMMARY OF THE INVENTION The present invention aims to solve the problems and drawbacks of the conventional radar processing apparatus described above and to provide a nine radar processing apparatus.

In other words, the present invention automatically performs the conventional complicated manual operations, and allows the arm 92 to be moved to a high degree in a short time even before or during radar processing. 2. The amount of light that passes through the slit opening is automatically adjusted to a predetermined irradiation range, and a certain proportion of the light passes through the slit opening using an optical means such as a dichroic mirror. Then, the laser beam is taken out from the laser optical path, and this light is irradiated onto a photodetector.The 14 watts of the LED light is converted into a good electrical signal according to the wattage, and this signal is input to the control device to control the workpiece. The actual notaur density irradiated onto the object is calculated, and the actual notower density calculated in this way is calculated. The excitation voltage or current of the Radhe oscillator is adjusted so that the difference is within the permissible value by comparing the power density with the desired power density stored in advance in the control device. The variable filter is operated by a control device to adjust the /l ratio of the radar light so that the i4 power density is automatically adjusted to be always maintained within a certain range.

This embodiment is shown in FIGS. 2 and 3. In this embodiment, the nine laser beams 2 oscillated from the laser oscillator 1 are:
It passes through the variable transmittance filter 18 and is bent by the dichroic mirror 3, and thus bent, the fI-v-de light 2
The irradiation range is limited by a rectangular slit 4 (a rectangular slit is illustrated in this embodiment, but a pinhole or the like may also be used, but the invention is not limited to this). The principle of reducing the projection onto the workpiece 7 is the same as the conventional one. Furthermore, the light from the slit illumination light @t3 is imaged through half mirrors 5 and 10.

The configuration that can be observed by the observation optical system 11 is also the same as that of the conventional example shown in FIG.

First, the embodiment shown in FIG. #I2 will be described. In the figure,
3' is a light beam whose transmittance and reflectance are known for the wavelengths of light 2 and 2. A rectangular opening loss slit 16 for field determination is provided on the transmitting side of the dichroic mirror 3', and the nine LED light transmitted through the dichroic mirror 3' is shaped into a rectangular shape and irradiated onto the photodetector 15. Additionally, an interference filter is provided to prevent the radar light irradiated onto the photodetector 15 from being interfered with by the light from the slit illumination light source 13. The phototaxis detector 15 irradiated in this manner generates a voltage or current depending on the amount of light or heat of the Rade light 2 generated by the Rade oscillator 1.
K is configured to be input to the control device n as an electrical signal. The rectangular opening loss slit 16 for shelf fixing and the rectangular opening slit 4 correspond to each other, and the dichroic mirror 3
The laser beam is taken out under the same conditions from the Radhe optical path that passes through the rectangular opening slit 4 and is irradiated onto the workpiece 7 via the photodetector 15. It will detect the luxury of radar light. 21
Nine shutters are installed in the Radhe optical path between the rectangular loss slit 4 and the objective lens 6, and are rounded to open and close the Radhe optical path. This shutter 21 reflects the dichroic mirror 3' and nine led lights 2
It has a characteristic of only blocking the light from the slit illumination light source 13 that has passed through the dichroic filter 3'. For example, the shutter 21 can be constructed by mechanically moving in and out a mirror corresponding to the dichroic mirror 3'. n is a control device and has a primary function. First, there is a function to capture and store information such as machining conditions of the workpiece 7 from a magnetic medium or manual input. power density, laser irradiation time, laser irradiation/4 to 3000 sq. These are various conditions necessary for laser processing, such as reflectance and accuracy rate for 20 wavelengths of laser light (e.g.). Next, the function of driving the X-Y table 17 to reproduce the position to be processed and the rectangular opening slit 4. A function of driving the 16 drive devices 14 and 17 to reproduce the irradiation range of the laser beam 2 that matches pre-stored processing condition information, receiving an electric signal from the photodetector 15, From this electric signal and the irradiation range of the radar beam 2 or the opening size of the slit, the power fi degree of the laser beam 2 that is actually irradiated onto the processing portion of the workpiece 7 is calculated, and the processing condition information stored in advance is calculated. One of the following functions is the function of comparing and determining f with V1jlf, the function of generating the Rede light 2 from the Rade oscillator l and controlling the excitation voltage or current, the function of irradiating the workpiece 7 with the Rade light 2, Alternatively, an operating device II having a function of controlling the shutter 4 that controls the laser beam R#r and closes the irradiation of the workpiece 7, etc.
II! It is equipped with In addition, a variable transmittance filter 18 whose transmittance changes continuously for 20 wavelengths of laser light and its driving device are provided, and the driving device is used instead of controlling the excitation voltage or line current of the Raded oscillation ill. It is also possible to control the power of the two laser beams by controlling the power of the two laser beams.

Fig. s3 shows another embodiment.The difference from the embodiment shown in Fig. 2 is that the measuring aperture slit 16 and its driving device 17 are eliminated, and the nine... Zuler 5
Instead, a dichroic mirror 8 is provided to take out the radar light for detection from the laser optical path. That is, by extracting the laser beam that has passed through the rectangular slit 4, detection Rade light having the same conditions as the Rade light irradiated onto the workpiece 7 is extracted. In this case, the shutter 21 is located in the laser beam path between the dichroic mirror 8 and the objective lens 6, and regardless of whether the shutter 21 is opened or closed, the detection radar beam is extracted from the laser beam path and the photodetector 15 It is possible to irradiate the area and input electrical signals to the control device at all times.

The operation of the ninth embodiment constructed as described above will now be described.

First, the operating procedure of the embodiment of the present application will be explained.

(2) Processing condition information is input manually or stored in the control device 22 using a magnetic medium such as a magnetic tape.

■ Drive device 14 according to the stored machining condition information.
, 17 are operated (in the case of the embodiment shown in FIG. 3, the drive value f
f114 only) and a rectangular opening slit 14. The aperture size of the rectangular opening 16 (rectangular in the case of the embodiment shown in FIG. 3, .'opening 14) is controlled, and the irradiation range or opening size of the slit is set.

■ Next, the workpiece 7 is placed on the X-Y table 17, and a signal is sent from the control device n based on the processing condition information (position information), and the X-Y table 17 moves, at least A workpiece enters the field of view of the observation optical system 11.

In some cases, the projection of the rectangular aperture slit 4 by the slit illumination light source 13 is observed and checked using the observation optical system 11, and if it is found to be misaligned, precise positioning is performed manually.

■ Laser oscillator 1 is turned on by a signal from control device a.
becomes N, and laser light 2 is generated. At this time, shutter 2
The laser beam 1 is kept closed and is reflected by the dichroic mirror 3', and the laser beam 2 does not irradiate the workpiece 7. In this state, the dichroic mirror 3'
The laser beam that has passed through the laser beam (in the embodiment shown in FIG. 3, the laser beam reflected by the aperture power 8) is passed through the fixing rectangular opening slit 16 (in the embodiment shown in FIG. 3, the rectangular opening slit 4). The light is shaped into a rectangle and is irradiated onto the photodetector 15 through an interference filter. The phototactic detector 15 irradiated in this way inputs an electric signal corresponding to the power of the laser beam 2 to the control device n. Optical elements provided in the optical path (dyke mirror 3',
Half mirror 5, shutter 21 in transparent state. An objective lens 6 and an interference filter are added, and in the case of the embodiment shown in FIG. 3, a dichroic mirror 8 is also added. ) is calculated from the transmittance and reflectance of the actual Rade light 2 irradiated onto the workpiece. This calculated Nol of Rede light 2
The power density actually irradiated to the workpiece is calculated from the irradiation range and the aperture size of the ore slit stored as machining condition information. It is stored as condition information.
If the two match within a certain tolerance range, the shutter 21 will be automatically opened by the control device n and the radar processing will be performed. ,・Determine whether to perform armpit adjustment.

In the above judgment, if it is determined that power adjustment should be performed, a signal is sent from the control device n to the drive device 19 of the Rade oscillator 1 or the variable transmittance filter 18, and the excitation voltage of the Rade oscillator 1 or By changing the current or the transmittance of the variable transmittance filter 18, the amount of radar light 2 irradiated onto the photodetector 15 and the processed portion of the workpiece 7 is changed. Regarding the arm of the radar light 2 that can be changed in this way, the computation and comparison judgment of the f-war density is carried out at fixed time intervals (
For example, /f adjustment is performed in 0.5 seconds, and calculation and comparison 9 judgment are performed in 0.1 seconds) alternately. However, when the calculation result falls within a certain tolerance range in comparison with the machining condition information, it is determined that the radar machining should be performed.

■ If the control device n judges in this way, the shutter 21
An electric signal is sent to the opening, and the portion to be processed of the workpiece 7 is irradiated with the radar light 2, thereby performing laser processing.

Even during laser processing, the control device n receives electrical signals from the photodetector 15 at regular intervals, and performs operations such as adjusting the arm and arm of the radar beam 2, calculating the density, and comparing. is repeated to maintain the power density within the allowable range while the power density is fluctuating.

■ Next, an electrical signal is sent from the control device ρ to the shutter 21 according to the processing condition information (laser irradiation time or number of arm pulses) stored in the control device ρ, and the shutter 21
1 is closed, irradiation to the workpiece 7 is stopped, and the radar processing is completed.

If necessary, the machining state is observed by the observation optical system 11, and when a signal to finish machining is manually inputted by one operator, 1
The X-Y table 17 is moved to reproduce the next workpiece position, and the next radar processing begins.

In this way, the laser light that is actually irradiated onto the workpiece 7 is optically taken out from the optical path of the laser light, and the laser beam emitted from the weir is irradiated onto the photodetector 15, and the workpiece 7 is inputs the power of the laser beam actually irradiated to the control device 22 as an electrical signal, compares it with processing condition information stored in the control device n, and controls the /4 power of the laser beam;
It performs stable radar processing completely automatically.

As described above in detail, according to the present invention, the 9 watts of the radar light that is actually irradiated onto the workpiece is converted into an electrical signal,
This is input into the control device and the actual irradiation is performed.9
The density of the round arm is calculated and the /l of the V-f light is controlled so that the calculated round arm density becomes the desired density. The laser beam density to be applied is a desired value and is adjusted while checking the laser beam density actually being irradiated, so that laser processing can be carried out more reliably. In addition to this, during laser processing, 4
・Wah'i! l! Since the adjustment is carried out, the f-war density must be checked at all times during the laser processing, which enables uniform laser processing and has the advantage of further improving the reliability of the laser processing. . Furthermore, since the rede processing time is greatly shortened and the rede processing is performed uniformly on all products, it has excellent effects such as further improving the vortex effect and the effect on quality assurance. .

[Brief explanation of the drawing]

FIG. 1 shows a conventional aperture projection type laser processing apparatus. FIGS. 2 and 3 show one embodiment of the present invention, and FIG.
The figure shows a system in which a rectangular aperture slit is used to extract the Radhe light, and FIG. 3 shows a system in which the rectangular aperture slit is omitted and a dichroic mirror is used to extract the Rade light. . 1... Rade oscillator, 2... Rade light, 3,3'・
... Dichroic mirror, 4... Rectangular aperture slit, 5... Half mirror 16... Objective lens, 7.
...Workpiece, 8...Dichroic mirror, 15.
...Photodetector, 16.. Rectangular aperture slit for measurement, Addition..Interference filter, n..Control device. Agent: Tadashi Akimoto, Patent Attorney (Continued from Figure 2, Page 1) 0 Inventor: Masaaki Okunaka, Hitachi, Ltd. Production Technology Laboratory, 292 Yoshida-cho, Totsuka-ku, Yokohama 0 Inventor: Takao Yonabe, Kodaira City 1450 Mizuhonmachi, Hitachi, Ltd., Musashi Factory 0 Inventor: Isao Tanabe, Kodaira City, Kamizuhonmachi 1450, Hitachi, Ltd. Musashi Factory

Claims (1)

[Claims] The radar light from the laser transmitter is reflected by the dichroic slurry, and the reflected light is guided to the objective lens through a slit and condensed to a predetermined area to be processed on the workpiece. ! In a Rade processing device that performs Rade processing by irradiating Rade light of degree F, a certain proportion of the amount of Rade light is extracted with respect to the amount of laser light passing through the slit, and the Rade light is irradiated to a photodetector through an interference filter. A good electrical signal is oscillated in response to the laser light output, and the electrical signal is input to the control Il @ position, and the actual power density of the laser light irradiated to the attached knee is calculated and controlled in advance. The power density of the Lede light is compared with the power density stored in the device, and the power density of the led light is 9. A reed processing device characterized by the following: