JPS60171776A - Method and device for feeding laser energy - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION The present invention provides a method and apparatus for delivering a laser beam, and more specifically, a method and apparatus for delivering a laser beam, and more specifically, a method and apparatus for delivering a laser beam and, more specifically, for producing a laser beam at an energy level sufficiently high for manufacturing purposes. Concerning the transmission of C through optical fibers.

Typically, the delivery of a laser beam to process materials is accomplished using a mirror and prism assembly to direct the beam. Optical laser beam 4J
When passing through Jil, it is possible to improve the 81i permissibility of beam direction. This flexibility makes it easy to access difficult parts of the workpiece during manufacturing.Drilling, cutting, welding and other treatments such as selective heat treatment and spray painting with a laser beam. However, this is possible using a laser located at a distance from the T section.

Ray 1r energy has been transmitted along optical fibers for purposes of laser communications as well as laser surgery in the medical field. In each case, the laser beam was continuous wave (CW) and did not exceed an average energy level of C1100. As much as 20 watts of CW energy from the CO2 ray 1F, which has a far-infrared wavelength of 10.6 micrometers, was transmitted through 11 optical fibers. CW energy levels of 100 W from Ray IP with a wavelength of 1.06 micrometers in the near-infrared have also been achieved. For uses such as plate making and fabric cutting,
Only CO2 lasers are used to process materials and optical fibers.
It is used in t. The average energy or peak f1 energy is not sufficient to weld, cut, drill, and heat treat metals at cost effective rates. G O2
Rayleigh's optical fiber is composed of thallium bromide and thallium iodide, and can have a transmittance of 55% at 10.6 micrometers. Cooling is required to cover it. The neodymium-iso-1 helium-aluminum-garnet laser, which is an energy source with a wavelength of 1.06 micrometers, is
A CW of 100 watts outside the river generates an average of 1 energy. Although such energy levels are suitable for limited metal processing, they have never been used. 1゜0
A peak energy nof in excess of 0.00 watts is more desirable for metal processing.

SUMMARY OF THE INVENTION This defense couples laser energy into a single optical system. This optical IJli screen is used as a light guide to deliver sufficient pulse energy to the workpiece for material processing. Solid neodymium-Y operating in a pulsed manner and with wavelengths in the near-infrared and visible spectrum
An Ic laser beam generated by an AG laser or other laser is connected to an optical illuminator, preferably made of quartz.
It is focused at one end of the miscellaneous core. 1. With peak levels in the kilowatt range. Energy is passed through the fiber to the C output end. The output laser beam is focused onto a workpiece at a sufficiently high energy density for manufacturing processes such as drilling, cutting, welding, heat treating, and laser spray painting.

This device has a lens that focuses the laser beam into a small spot with a diameter smaller than the diameter of the core of the optical Ili. The aperture value is such that the internal angle of the focused beam is less than about 24°. In certain embodiments, the bond is made through a retaining jig made of copper or gold. This jig reflects the laser energy,
Stray energy is prevented from entering the coating of the optical fiber and causing it to melt and leak. Remove the coating from the ends of the fibers and fit the wear into the holes in the jig. The second fruit color interval for an average energy level of up to 250W1 uses another manual combiner J-'i-J'C. Sengumi rust 1i
1) Peel off the covering (1) and the shield, and in the next part, remove only the shield and place the end of the fiber thus prepared on a glass holder. There is a lens device on the output side (which collimates and focuses the laser beam onto the workpiece).

This device is a flexible laser beam delivery device with the lowest optical loss compared to Akira's device fTj It, making it easier for people to master the operation of the laser beam. This is particularly useful in metal processing using 1'' control equipment.

Revised Explanation 11 By the Ic laser energy delivery device shown in the drawing,
The processing of gold II alone and the processing of other materials is (-1).

Average energy levels on the order of 250 watts and peak energies of several kilowatts are transmitted through the individual optical fibers. A Neadium-Illium Aluminum Garnet laser with a wavelength in the near-infrared range is operated in a pulsed manner.

Other suitable solid-state lasers include the ruby laser, which has a wave length of 680 nanometers, and the Arechiline Dry Laser C, which has a wavelength of 630 to 730 nanometers.
Both are within the visible spectrum 1e range.

All wavelengths in the near-infrared and visible ranges melt 1Mi
Without exception, it is transmitted in the 6-Eng Optical IIi string. This type of optical fiber has a flexibility of C, (
It is preferable because it is a pure material and can be drawn into a good fiber. Impurities absorb energy 1
There are 111 directions. ′! The A position is used to combine the laser energy into the fibers, and also to extract the I, beam from the fibers to an energy density of 1, sufficient for processing the material. C
There is.

In Figure 1, Nd-YAG Rayleigh 1 used in pulse mode
0 is coupled to a fused 6-inch optical fiber 11 with a diameter i and an ooo microphone L1 meter. For this purpose, the ray IJ' beam 12 is focused by means of a lens 13 onto the end of the fiber. Two rays '1 are required for the laser energy to enter the fiber. First, the small focus plane 1~ has a diameter smaller than the diameter of the core 14 of H. Second
In addition, the aperture 11 of the optical fiber is such that the internal angle (such as the cone angle) of the focused beam is less than 22° to 24°. Turn to get the best result.]
The end of the core 4 was ground by 1Ill so that it was optically flat 114mm, and it had a +44 resistance and 11. Set up 15 seedlings. C-bond 11 is made through a copper holding jig 1-6 which has a hole for receiving 1/411=J from the end of the fiber.
Remove the transparent 4" silicon coating 17. Copper jig 1
6 is the best for stray rays that don't get into the ends of the fibers!・It helps to protect the fiber coating from energy and melts the coating.81
to prevent; Copper has a medium energy level1.
It has a tendency to reflect laser energy of 0.06 micrometers. A better material is gold, which is a more reflective material.

To explain the cross section of the optical fiber 11 shown in FIG. Optical fibers must have a buoy shield or jacket 18. When using fused glass optical fibers with a glass coating, the IQ properties of the fibers will be reduced. This is because the 1.06 micrometer wavelength is transparent to the glass, which reduces the risk of damage to the coating. The wear is less than 1mm!
'1 diameter.

Fibers thicker than this have less flexibility.

After transmitting the C laser energy through optical fiber 11, lens assemblies 19 and 20 are used to collimate and focus the laser beam. The beam emerging from the output end of the optical fiber has a tendency to diverge. The beam is collimated by lens 19 and focused by lens 20 onto the workpiece 21. The energy density of the beam focused at the focal plane is sufficient for various metal processing. To protect the lens from metal vapor, laser
The beam can pass through 6rl -F 4N , 22. Three lens element anti-reflection coatings increase transmission.

This 41 average energy level up to 155 watts!
Conveyed to I. 0.6 ms pulse width (pulse 1k)
and a pulse rate e1/I of 30 pulses per second, 000
A peak energy range of 3,000 sots1 to (3,000 sots.
An energy density of 2 was achieved. A laser pulse energy of 155 watts was transmitted through a 1 millimeter optical fiber with no detectable attenuation when the bend radius was increased to 8114 (200 millimeters). With a fiber bend radius of 1.5 inches (37.5 millimeters), the transmission at 1.06 micrometers is 87%. As a result of focusing the rake beam output from an optical fiber onto a 19 x 0.3011 J (0.75 mm) Inconel 718 workpiece,
Both drilling and cutting of materials were possible.

The diameter of the output lens 19,20 may be much smaller than shown, so that the output end can be moved around 1
becomes even easier. The ends of the fibers can be shaved to become a lens element or part of a lens, or can be cut into separate hexagons.

The human-powered mechanism in Figure 1 has an average rate tF of 155 watts 1 ~
・I can only get Ninergi. This is not sufficient for all processing tasks. Higher 1 energies are prohibited due to thermal constraints at the input coupling. The improved coupler shown in FIG. 3 was used to transfer an average energy of 250 watts to the optical fiber. 0 from the tip of the fiber.
Strip off 75 inches of the silicone coating 17 and shield 18. In the next part, remove only the shield by the same distance. The end thus prepared is placed in a Pyrex (O, registered trademark) holder 23 and positioned at the desired focal plane of the laser. This °C prepared end has two areas,
That is, the beams can be connected through the core and the air and the core and the coating. The first zone allows a highly divergent incident beam to enter the fiber 11 through the larger acceptance angle created at the core-air interface. A second area provides a direct reflection of the collected light energy. 2 is guaranteed. A third section consisting of the core, sheath and shield provides a sturdy housing for handling the fibers.

An average of up to 250 watts for a fiber of approximately 55 meters in length1
communicated energy level. With a pulse width of 0.2 ms and a pulse rate of 200 10 s pulses, b, 000/
A peak 1 energy range of 9.000 W 1 to 1 I was achieved. After focusing the output C′ beam of the optical fiber,
Soil energy density U (106 no J I) that allows drilling and cutting
Q7W/C1112) was achieved and IC.

Even if the pulse energy of 250 watts of Nd-YAG ray is transmitted to a 1 mm optical fiber,
l! If the radius of the rough bend was greater than 411'j (100 millimeters), there was no detectable attenuation. When the radius is 411 iJ, the transmission at 1.06 mCl meters is 90%. Thickness 0゜0001
14 (1,54mm 1~le) titanium 6A1-4v
It was possible to drill and cut workpieces. By having the ability to transfer larger amounts of average energy, this device is very flexible for the iA specific processing industry.

The main advantage of fiber optic laser delivery devices is increased beam steering flexibility. The degree of freedom in manipulating the laser beam increases. Since optical fibers are basically lightweight, the laser beam can move at high speeds and in almost any direction without moving. The ability to position the laser remote from the processing area is another advantage of transmitting the laser beam through a light guide, such as an optical fiber. Because of the inherent flexibility of the fiber optic laser beam delivery system, the system is highly self-sufficient for laser processing using a robotic controller.

Although the invention has been particularly illustrated and described with reference to preferred embodiments, it will be obvious that various modifications may be made within the scope of the invention.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a fiber optic device coupled to a laser used to apply laser energy to metal workpieces;
The figure is a longitudinal cross-sectional view of an optical fiber, showing the passage of a Radhe beam along the core. Figure 3 shows more optical fibers! An improved human-powered PGM 1fii is used to transfer the average energy of Ji. Description of main loads ÷] 10: Laser, 11: Optical fiber, 13: Focusing lens, 19.20 + output lens device. patent applicant

Claims (1)

[Claims] 1) In a method for performing a manufacturing process without transmitting laser energy, a pulsed laser beam of wavelength in the near-infrared or visible range is generated, and the laser energy is not transmitted. Focusing the beam to a small spot on the end of the core of one optical fiber delivers energy with a peak level in the range of 1-kilowal to the optical 1u
11& and refocusing the emerging beam onto the workpiece with an energy density of 1 sufficient to process the material. 2. In the ts method as claimed in claim 1), C1 the laser beam is focused into a small spot having a diameter smaller than the diameter of the core, and the frontage value is such that the internal angle of the focused beam is less than about 24°. How to make it have a small angle. 3) A method as claimed in claim 1), wherein the core end of the optical fiber is optically flat and has an anti-reflection coating to enhance energy coupling. 4) The method of claim 1), wherein an average energy level of up to about 250 watts is transmitted to the optical fiber. 5) a pulsed laser that generates a laser beam in the near-infrared or visible range of wavelength; an optical fiber having a quartz core and coating; said optical fiber transmits over 1 kilowatt of peak energy to its output end and further collimates the emerging laser beam; An industrial laser energy delivery system having means for focusing onto a workpiece to carry out the treatment. 6) In the industrial laser energy delivery device according to claim 5), the laser is an industrial laser energy delivery device selected from the group consisting of a neodymium-YAG laser, a ruby laser, and an alexandrite laser. Device. 7) In the industrial laser energy delivery device according to claim 5), C1 a holding jig for the end of the optical fiber reflects the laser beam so that the stray beam does not enter the coating. Industrial laser energy delivery equipment. 8) In the industrial laser energy delivery device according to claim 5), the coating at 1@ of the optical fiber is removed and the laser beam is reflected to cause the melting at t°C. An industrial laser energy delivery device in which the optical fiber is placed in a hole in a holding jig made of metal such as copper and gold, such that the optical fiber can be prevented. 9) Particularly in the industrial laser energy delivery device according to i,' [Claim 5), - C1 removing the optical fiber 1n and the shield thereon over a short distance 1 from one end of the optical fiber; Remove only the shield in the next section, place the end of the optical fiber thus adjusted on a glass holder, and attach it to the glass holder.
industrial laser energy delivery equipment. 10) Neodymium-YAG operating in a pulsed manner producing a laser beam with a wavelength of 1.06 micrometres
a laser, one optical fiber having a core of fused silica, a coating and a shield, and directing the light beam to one of the cores of the optical fiber.
At the end, the core diameter J, focuses into a small spot with a smaller diameter and the internal angle of the focused beam is 24
The optics 11[E act as a light guide to transmit peak energy in the kilowatt range to the output end; An industrial laser If energy delivery system having a lens system that collimates the exiting laser beam and focuses it on the workpiece for performing metal processing. 11) The industrial laser described in claim 10)
In an energy delivery device, the coating and shielding on the optical fiber 1 is removed to reflect the laser beam and prevent stray light from melting the coating - retaining the copper. Insert the +'+Fj optical aI & navy blue into the hole of the jig and lζ industrial laser energy delivery device. 12. Industrial Ray 1F described in claim 10)
・In one energy delivery device, the coating and shielding is removed over a short distance from one end of the optical fiber, and the shielding is removed at approximately the same distance in the next section, and thus Industrial Ray 1F/Energy delivery device where the end of the prepared optical fiber is placed inside the glass container 1.1. 13) The industrial laser described in claim 10)
In the energy delivery device, the optical W! Industrial laser energy delivery device whose main coating is transparent silicon. 14) The industrial relay I described in claim 10)
A. In the energy delivery device, the one end of the optical fiber to which the beam is coupled is coated with an optically flat C1 anti-reflection coating. "Jru Industrial Laser"
・J~ Energy sending device.