JPH02258185A - Laser beam machine - Google Patents

Abstract

PURPOSE:To contribute to maintenance of an optical fiber by projecting an inspection beam to one end face of the optical fiber and detecting the inspection beam from the other end face, setting a reference detection beam as a reference signal, comparing the reference signal with the inspection beam and controlling a light source for a machining laser beam in response to a compared result. CONSTITUTION:The machining laser beam is guided to the second end face 2b from the first end face 2a of the optical fiber 2 from the light source 1 for the machining laser beam and an object 3 to be machined is subjected to laser beam machining. The inspection beam is then projected on the first end face 2a of the optical fiber 2 from a light source 10 for the inspection beam and the inspection beam exiting from the other end face 2b is detected by a detector 6. The reference detection beam is set as the reference signal in this detection signal and the reference signal is compared with the inspection beam by a comparison means 8. The light source 1 for the machining laser beam is controlled by a control means 9 in response to the compared result. By this method, the deterioration of the optical fiber is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a laser device that transmits laser light emitted from a laser light source through an optical fiber and irradiates a desired position of an irradiation object with the laser light, and in particular, The present invention relates to a laser device equipped with means for detecting an abnormality occurring in an optical fiber. This laser device can irradiate the desired position of the irradiation target with laser light, so it is widely used for processing industrial products and treatment in the medical field (hereinafter referred to as
The irradiation of laser light onto the core part during the processing and treatment of industrial products with laser light is collectively referred to as "laser processing").

[Prior Art] When this type of laser device utilizes the flexibility of an optical fiber to irradiate a desired position of a workpiece with laser light, it imposes a load such as bending on the optical fiber. If this load becomes excessive, the optical fiber may break or break, and there is a risk that the laser light traveling within the optical fiber may leak to the outside. In order to solve these problems, for example, if an abnormal situation such as breakage or breakage occurs in the optical fiber that transmits the laser beam,
Focusing on the phenomenon in which the amount of laser light changes after passing through an optical fiber, a laser device has been proposed that is equipped with an optical fiber abnormality detection device that detects the fluctuation in the amount of light and identifies whether the optical fiber is in good condition or abnormal. (Refer to Japanese Unexamined Patent Publication No. 155833/1983).

FIG. 3 shows a laser device according to the above proposal. This laser device includes a processing laser light source 1 as a basic configuration for irradiating the processing laser beam onto the processing object 3, and a processing laser beam emitted from the processing laser light source 1 to irradiate the processing laser beam onto the processing object 3. It is equipped with an optical fiber 2 for guiding light. Then, the processing laser If emitted from the processing laser light source 1
A semi-transmissive mirror 11 and a condensing lens 4 are sequentially arranged on the path through which the light reaches the first end surface 2a of the optical fiber 2.
Further, the light emitted from the second end face 2b of the optical fiber 2 is
A condensing lens 5 is arranged on the path through which the light passes toward the workpiece 3. Therefore, the added energy light emitted from the processing laser light source 1 enters the semi-transmissive mirror 11, and the semi-transmissive mirror 11 separates the transmitted light that enters the second detector 7, which will be described later, and toward the condenser lens 4. It is separated into the traveling reflected light. This one reflected light is focused on the first end surface 2a of the optical fiber 2 by the condensing lens 4, and after passing through the optical fiber, it exits from the second end surface 2b, and then passes through the condensing lens 5. The light is focused on the workpiece 3 by. As a result, the workpiece 3 can be laser-processed 77I1.

Furthermore, in addition to the basic configuration for laser processing described above, this laser device also has the following features:
It is equipped with an optical fiber abnormality detector that stops the processing laser light source 1. This optical fiber abnormality detector includes a first detector 6 and a second detector 7 that detect the amount of processing laser light that is an indicator of the state of the optical fiber 2, and both detections obtained by these detectors. A signal processing section 8 which is a comparison means for identifying whether the optical fiber 2 is normal or abnormal based on the signal, and a control means 9 which controls the operation of the processing laser light source 1 in response to commands from the signal processing section 8. Become. The second detector 7 detects the laser beam 11 that has passed through the partially transmitting mirror 11, and the first detector 6 detects the processing laser beam that has been reflected on the surface of the condenser lens 5. Detected.

This optical fiber abnormality detection device detects that when an abnormality such as breakage, breakage, breakage, etc. occurs in the optical fiber 2, the processing laser beam traveling through the optical fiber 2 is absorbed or scattered at the safe part, and as a result, the optical fiber 2 The amount of processing laser light emitted from the second end surface 2b of the optical fiber 2 is lower than that when the optical fiber 2 is in normal condition. The processing laser beam is passed through. At this time, the first detector 6 and the second detector 7 detect the amount of light before and after the laser beam passes through the optical fiber 2, respectively.
Using the 2) type 1 detection signal obtained in the signal processing section 8 as a reference signal, the value of its ratio is stored in advance. After that, use this laser device to perform normal laser processing.
If the above-mentioned abnormality occurs in the optical fiber 2 during this process, the amount of light detected by the first detector 6 will be lower than when it is normal. A difference occurs between the value obtained by calculating the ratio of the two types of detection signals obtained from the second detector 7 and the value of the ratio of the reference signal described above.

The signal processing unit 8 determines that an abnormality has occurred in the optical fiber 2 based on such a difference, and sends a stop signal to the control unit 9.
The control means 9 stops the processing laser light source 1 in response to this stop signal.

In this way, if an abnormality occurs in the optical fiber during the process of laser processing, the processing laser light source 1 is stopped, and the processing laser is applied from the n-opening of the optical fiber 2, overlooking the abnormality in the optical fiber 2. It is possible to prevent light from leaking.

[Problems to be solved by the invention] However, the conventional laser device mentioned above uses the processing laser beam as the detection light for detecting the optical fiber. It is not possible to detect the state of the optical fiber before the d1 irradiation of the laser beam. For this reason,
The following problem could be avoided if the state of the optical fiber could be detected before the processing laser beam is emitted. Namely, there is an absorber on the end face of the optical fiber that absorbs and covers the processing laser beam. If the material is coated with -C, it will generate a large amount of heat and the processing laser beam will be absorbed by the absorber, thereby causing thermal destruction. If such a situation occurs, the end face of the optical fiber that has been thermally destroyed will be forced to undergo C1 wear, and in some cases, the optical fiber will have to be replaced. In addition, even if there is only one scratch on an optical fiber, even if it is a minor one, irradiation of the damaged part with the laser beam can accelerate the damage and even lead to destruction3. First of all, there was a problem with J3 in terms of the maintenance of the optical fiber. Furthermore, if the above-mentioned minor damage reaches the point of destruction, or
If the tool has already been damaged during use, there is a risk that the processing laser beam will leak outside from the damaged portion. However, problems still remain in terms of safety when operating the laser device, which was the main purpose of the conventional Rayleigh device.The present invention has been developed in view of these problems. The purpose is to provide a SEA device that can detect the state of the optical fiber and operate it safely not only during the emission of the processing laser beam but also before the emission of the processing laser beam. Another object of the present invention is to provide a Rayleigh device which does not cause any damage to the optical fiber during the process of detecting the condition of the optical fiber.

[Means for Solving the Problems] A laser device of the present invention includes a processing laser light source, and a light guide for guiding processing laser light emitted from the processing laser light source from a first glue surface to a second end surface. The processing laser beam is used to apply laser processing to the workpiece using the processing laser beam.
In the laser apparatus, a light source for test light emits test light consistent with the laser processing to one of the first and second end faces of the optical fiber; A detector detects the test light emitted from the CIJ plane 921, and a detector detects the test light emitted from the CIJ plane. and compares this reference signal with the detection signal of the inspection light at 451 when inspecting the optical fiber, and in response to the comparison result obtained by the comparison means, the processing laser light source is The present invention is characterized by comprising a control means for controlling the Rayleigh light to be in a state in which it can be emitted or in a state in which it cannot be emitted.

1 Effect 1 The laser device of the present invention is equipped with a light source for inspection light separately from the light source for the laser, so that the laser device of the present invention allows the inspection light to pass through the optical fiber regardless of whether or not the laser beam is emitted. With this, it is possible to detect the current status of A. Further, the light source for the inspection light can be placed on either side of the first and second end faces of the optical fiber. Since the inspection light emitted from the inspection light source does not contribute to laser processing, the heat J energy absorbed during the process of passing through the optical fiber is
Compared to laser light for processing, it can be kept much lower.

In the C1 comparison means, among the detection signals obtained by the detector, the detection signal of the test light that has passed through the optical fiber in the reference state is set in advance as a reference signal, and this reference signal and other signals obtained from time to time are Since the detection signal, that is, the detection signal at the time of inspection, is compared, it is possible to judge whether the optical fiber deviates from the reference state.

Furthermore, in response to the comparison result obtained by the comparison means, the processing laser light source is controlled by the control means so as to be in a state in which the processing laser beam can be emitted or in a state in which it cannot be emitted. The processing laser beam will not be emitted to an optical fiber that deviates from the

[Example] Hereinafter, an example of a laser device according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of a laser device according to a first embodiment, and FIG. 2 is a configuration diagram of a laser device according to a second embodiment. In FIGS. 1 and 2, the same or equivalent components as those of the conventional laser apparatus shown in FIG. 3 are designated by the same reference numerals.

First, a laser device according to a first embodiment of the present invention will be explained with reference to FIG. First, the optical system of this laser device will be explained.

This laser device includes a processing laser light source 1, a guide light light source 20, and an inspection light light source 10 as light sources serving as the sources of the optical system.

The processing laser light source 1 emits a processing laser beam with a high output having a wavelength that matches the absorption wavelength of the workpiece 3 in order to generate heat generation phenomena such as evaporation or melting at the processing location 3a of the workpiece 3. It is a possible light source. The light source 1 for Kanil +y of this embodiment uses E r : Y as a laser medium.
By using and exciting AG, Rayleigh light with a wavelength of 3IMl can be emitted with an output of about 1J.

The guide light light source 20 emits a guide light, which is visible light, used to aim the applied erage light at the processing location 3a of the workpiece 3, before irradiating the workpiece with the above-mentioned processing laser light. It is something to cover. In this embodiment, a 1-1ONe laser is used as the light source 20 for guide light. As a result, guide light having a wavelength of 633 nm, which is in the visible range, can be emitted with an output of about 2 mW.

The inspection light light source 10 is a light source that emits inspection light that indicates deviation of the optical fiber 2 from the reference state as a change in the amount of light after passing through the optical fiber 2. Since this inspection light does not contribute to the laser beam applied to the object 3 by the processing laser beam, heat is generated when the inspection light is absorbed or scattered inside the optical fiber 2, which causes fluctuations in the amount of light. It doesn't bring anything. In this embodiment, a light emitting diode that emits a wavelength of 55 Qnm with an output of 1 mW is used.

Therefore, the optical path of the laser device of this embodiment is formed by each of the lights emitted from the three types of light sources described above.

First, the optical path that the processing laser light emitted from the processing laser light source 1 travels includes the 11th circuit from the processing laser light source 1 to the first end surface 2a of the optical fiber 7 and fiber 2, and the 1st circuit of the optical fiber 2. A second path from the end surface 2a to the second end surface 2b, and a third path from the second end surface 2b to the workpiece 3.
It consists of a route.

The first path includes, along the traveling direction of the processing laser beam,
A partially transmitting mirror 21 and a partially transmitting mirror 12 are sequentially arranged. One partially transmitting mirror 21 guides the guide light emitted from the kite light light source 20 to the optical path of the processing laser light. Thereby, the guide light partially passes through the transmitting mirror 21 and then shares the same optical path as the processing laser light until it reaches the workpiece 3. In this way, the optical path of the guide light is formed. The other partially transmitting mirror 12 connects the optical path of the inspection light emitted from the inspection light light source 10 to the second detector 7 that detects the amount of the inspection light before passing through the optical fiber 2, and the third optical path. The optical path is separated into an optical path that matches the optical path of the processing laser beam up to the partially transparent cap 13 disposed on the 'M path. The optical path of the inspection light is formed by these optical paths and the optical path from the partially transmitting mirror 13 to the first detector 6 which detects the inspection light h1 after passing through the optical fiber 2.

Next, the optical elements arranged in the above-mentioned optical path will be further explained.

The partially transmitting mirror 21 has a film formed on each of its opposing main surfaces to determine wavelength selectivity, transmitting approximately 100% of the wavelength component of the processing laser beam and reflecting approximately 100% of the wavelength component of the guide light. ing. The processing laser beam is incident on one of the opposing main surfaces, and the guide light is incident on the other, and the angle between the optical axis of each incident light and the main surface is 45. It is set at a certain time. Therefore, its main surface is inclined so that the guide light reflected from the main surface travels toward the optical fiber 2.

The partially transmitting mirror 12 transmits approximately 100% of each wavelength component of the primary light and the guide light on each of its opposing main surfaces, and transmits approximately 100% of the wavelength components of the inspection light in a ratio of approximately 2 to 8.
A film is formed that determines the wavelength selectivity of separating the transmitted light and the anti-QA mirror at a ratio of . Then, the laser 1f light and the guide light q4 are made to enter one of the opposing main surfaces, and
Inspection light is incident on the other side, and the angles between the optical axis of each incident light and the main surface are both set to 45 degrees. The main surface is inclined so that the inspection light reflected from the main surface travels toward the optical fiber 2.

Further, the partially transmitting mirror 13 transmits approximately 10 wavelength components of the processing laser beam and the guide light onto each of its opposing main surfaces.
A film is formed that transmits 0% and reflects almost 100% of the wavelength component of the inspection light, which covers the wavelength selectivity to 0. The main surface thereof is inclined at 45 degrees with respect to the optical axis shared by the processing laser beam, the guide light, and the inspection light. and,
Its main surface is inclined such that the inspection light reflected on the main surface travels towards the first detector 6.

Further, the optical fiber 2 corresponding to the second path has a first end surface 2a and a second end surface 2b facing each other, and a side surface extending between these end surfaces. The optical fiber 2 of this embodiment is made of fluoride glass and is formed into a shape with a core diameter of 450mm, a cladding diameter of 500mm, and a total length of 2m. And, because of its flexibility, it is possible to avoid changing the direction to the second end surface 2b.

Furthermore, by arranging a condenser lens 4 between the partially transmitting mirror 12 in the first path and the first end surface 2a of the optical fiber 2, the processing laser beam and guide light that have passed through the partially transmitting mirror 12 are The inspection light is focused on the first end surface 2a of the optical fiber 2. Furthermore, by arranging the condenser lens 5 between the partially transmitting mirror 13 and the workpiece 3 in the third path, the guide light that has passed through the partly transmitting mirror 13 and Processing laser light is focused.

It should be noted that both of the partially transmitting mirrors and the condensing lenses described above are obtained by processing a sapphire material that absorbs little processing laser light.

Next, a description will be given of the means from detecting the inspection light to controlling the laser light source 1 based on the detection signal.

This means includes a second detector 7 that photoelectrically converts the test light before passing through the optical fiber 2, a first detector 6 that photoelectrically converts the test light after passing through the optical fiber 2, and these detectors. Comparison means 8 calculates the ratio of both detection signals obtained in , and compares the value with the detection signal 1q obtained when passing through the optical fiber 2 in a pre-stored reference state, that is, the ratio of the reference signal. and a control means 9 for controlling the processing laser light of the laser light source 1 to be in a state in which it can be emitted or in a state in which it cannot be emitted in response to the comparison result obtained by the comparison means 8. Consisting of Furthermore, comparison means 8
The reference state of the optical fiber 2 when obtaining the reference signal to be stored in advance is defined as one in which the amount of laser light after passing through the optical fiber 2 is within a predetermined range. That is, the predetermined range is defined as the upper limit of the amount of light in a state where there is no absorption of processing laser light due to structural defects of the optical fiber 2 such as chipping, breakage, breakage, etc., excluding absorption inherent to the material of the optical fiber 2, and This range exceeds the amount of light in a state where there is an absorber attached to the end face of the optical fiber 2 or attached to the end face of the optical fiber 2 that causes the Ellery light to leak to the outside of the optical fiber 2 or deteriorates the optical fiber 2. In this embodiment, the detection signal obtained by the first detector 6 is referred to as IO,
The detection signal obtained by the detector 7 with a resistance of 2 is defined as Ii, and the value of the ratio 10/1 is in the range of more than 0.8 and less than 1.0, which is regarded as the reference state of the optical fiber 2. There is.

That is, the optical fiber 2 for which Io/I i = 0.8 is obtained as the calculation result, passes the processing laser beam from the first end face 2a to the second end face 2a.
The processing laser beam has a structural defect that causes the processing laser light to leak to the outside when it advances to the end face 2b of the optical fiber 2, or an absorber that causes the end face of the optical fiber 2 to deteriorate due to heat generation on the optical path of the processing laser light. The optical fiber 2 that has obtained Io/l1-=1.0, which is the upper limit of the predetermined range, has no structural defects or absorbers.

Further, the control means 9 opens and closes a shielding plate (not shown) disposed at the processing laser light emission hole (not shown) of the processing laser light source 1 to advance or block the processing laser light. As a result, the processing laser light source 1 is controlled to be in a state where it can emit processing laser light or a state where it cannot emit processing laser light (fp).

Next, the operation of this laser device will be explained.

This laser device detects whether or not the optical fiber 2 deviates from the reference state, not only during the emission of the processing beam, but also when the optical fiber 2 deviates from the reference state.
It is possible to cover the inspection even before emission. When inspecting the condition of the optical fiber 2 before emitting the radiation beam, first, the light source 10 for inspection light is turned on. The inspection light emitted from the inspection light light source 10 partially enters the transmitting mirror 12, passes through the negative section of the transmitting mirror 12, and enters the second detector 7 and the condensing lens 4. The reflected light is separated from the reflected light that is focused on the first end surface 2a of the optical fiber 2.

The inspection light focused on the first end surface 2a travels inside the optical fiber covered with the side surface and exits from the second end surface 2b, and is then partially reflected by the transmitting mirror 13 to be detected by the first detection light. 4 is incident on the vessel 6. Here, each of the first detector 6 and the second detector 7 r q! The comparison means 8 performs a ratio of 10/Ii on the detected detection signals IO and 11, and compares the result with the ratio of the reference signal stored in the comparison means 8 in advance. As mentioned above! (as expected, the value of lo/Ii is 0
．． Since the ratio of the reference signal is set to be within the range of 8 to 1.0, the detection signal ratio I obtained during the inspection is
If the value of O/■l is, for example, 0.7, the comparing means 8 determines that the optical fiber 2 is in a state deviating from the reference state, and the processing laser light source 1 becomes unable to emit the processing laser beam. A command to close is sent to the control means 5 as a comparison result. In response to this command, the control means 9 blocks the optical path of the machining laser beam with a shielding plate, so that the machining laser light source 1 becomes unable to emit the machining laser beam. Also, inspection 1.1 in 1! If the ratio of the detected detector g is in the range of more than 0°8 and less than 1.0, processing laser light can be sent from the processing laser light source 1 from the comparison means 8 to the control means 9. A command is sent to bring the shielding plate into the 2i state, and in response to this command, the control means 9 applies the shielding plate.
- Release it from the optical path of the laser beam so that the processing laser beam can be emitted. In this way, the light source 1 for the heating element is activated and the iFI+ is started! DA′?
If the optical fiber 2 is already in a state that has deviated from the semi-standard state before the processing, the laser light source 1 should be turned off once until the processing laser beam cannot be emitted. ,
Leakage of the applied energy from the optical fiber 2 or optical flux due to absorbers attached to the end face of the optical fiber 2.
It is possible to prevent the deterioration of the fiber 2 +L.

Next, apply processing energy light from the first light source for processing laser]
A case J8 in which the state of the optical fiber 2 is inspected during the process of performing laser processing by irradiating the processing location 3a of the object 3 will be explained.

When irradiating the processing laser beam to two points 3a of the workpiece 3, the processing laser beam is focused on the condensing lens 5 and the processing point is It is necessary to perform alignment 1 so that 3a matches.In this alignment 1, first, the light source 20 for guide light is turned on.The guide light emitted from this light source 20 for guide light is partially transmitted through the transmissive mirror. 21, and is partially reflected by the transmitting mirror 21 so as to proceed toward the first beam i: surface 2a of the optical fiber 2. This reflected light passes partially through the transmitting mirror 12. After passing through, the condensing lens 4 condenses the light onto the first end surface 2a of the optical fiber 2.Then, the condensed guide light travels inside the optical fiber 2 covered by the side surface and reaches the second end surface 2b. Furthermore, this emitted guide light partly passes through the transmitting mirror 13 and is then condensed at the focal point of the condensing lens 5. This condensing point and the processing location 3a of the workpiece 3 The flexibility of the optical fiber 2 is utilized to connect the second
Alignment 1- is achieved by partially changing the direction of the end surface 2b of the transmissive mirror 13, the condensing lens 5, and the first detector 6. After the alignment is completed in this way, the light source 20 for the guide light is turned off, and the light source 1 for the processing laser and the light source 10 for the inspection light are operated as shown in 1). The processing laser light emitted from one processing laser light source 1 is
As mentioned above, since it follows the same optical path as the guide light from the partially transmitting mirror 21 to the processing location 3a, the partially transmitting mirror 21 follows the same optical path as the guide light.
7-Q 1 After entering the mirror 21, the light passes through the same path as the guide light and is focused on the processing location 3a. The inspection light emitted from the other inspection light light source 10 enters -.partially transmitted ↓J12, and through this partially transmitting mirror 12, the transmitted light proceeds to the second detector 7 and partially reaches the transmitting mirror 13. The beam is separated into the beam of radiation, which is being emitted, and the reflected inspection beam, which follows the same optical path. This reflected inspection light is partially transmitted through the transmitting mirror 13.
The first
The respective detection signals obtained by the detector 6 and the second detector 7 are sent to the comparing means 8, where the processing laser beams described above are output.
l) In the process of checking the state of the light beams and ibar before performing J, the comparison results are sent to the control means 9 through the same red and latitude as described in c).

If the comparison result is a command to enable the emission of the machining laser beam, the control means 9 releases the shielding plate from the optical path of the machining laser beam and starts emitting the machining laser beam. The operation of the laser light source 1 is continued. or,
If the comparison result sent from the comparison means 8 is a command that makes it impossible to emit the processing laser beam, the optical path of the processing laser beam is blocked by the shielding plate, and the processing laser beam from the processing laser light source 1 is interrupted. stop the emission of. In this way, even when the processing laser beam is being emitted, if the optical fiber 2 deviates from the reference state during the process, the processing laser light source 1 is brought into a state where the processing laser beam cannot be emitted.
That is, by stopping the emission of the IJ' light, it is possible to prevent the processing laser light from leaking from the optical fiber 2 to the outside or to prevent deterioration due to the absorber attached to the end face of the optical fiber 2.

Next, a laser device according to a second embodiment of the present invention will be described with reference to FIG. The laser device according to the second embodiment is different in that the inspection light is passed from the second end surface 2[) of the optical fiber 2 to the first end surface 2a, that is, the traveling direction of the inspection light is different from that of the first embodiment. This differs from the laser device of the first embodiment in that the direction is opposite to that of the laser device.

To explain this difference in detail, the components surrounded by broken lines in the figure, that is, the first detector 6, the second detector 7, the partially transmitting mirror 15, and the inspection light source 10 are different from those in the first embodiment. Unlike the laser device in the example, the other components and the effects derived from the components are the same as in the first embodiment. Therefore, only the different constituent elements will be explained here, and the explanation of the other constituent elements will be omitted. A transmissive mirror 14 and a partially transmissive mirror 15 are disposed on the third path, respectively.

This partially transmitting mirror 15 is connected to the second end surface 2b of the optical fiber 2.
The wavelength components of the inspection light are provided on each of the opposing main surfaces of the partially transmissive mirror 15, which is interposed between the laser beam and the condenser lens 5 and serves as a path for the processing laser beam, the guide light, and the inspection light. 8 to 2
A film is formed which has a wavelength selectivity that separates reflected light and transmitted light at a ratio of 1, and transmits almost 100% of the wavelength components of the processing laser light and guide light. Thus, the processing energy light, the guide light, and the inspection light are made incident on one of the opposing main surfaces, and the angle between the optical axis of each incident light and the main surface is 45 degrees. The main surface is inclined so that the inspection light reflected from the main surface travels toward the optical fiber 2.

Further, the partially transmitting mirror 14 is interposed between the partially transmitting mirror 21 and the first end surface 2a of the optical fiber 2, and has opposing main beams that serve as paths for processing laser light, guide light, and inspection light. A film is formed on each surface, which has wavelength selectivity that allows approximately 100% of the processing laser beam and guide light to pass therethrough and reflects approximately 100% of the inspection light. Then, a processing laser beam and a guide beam are incident on one of the opposing main surfaces,
Also, the inspection light is on the other side! ) The angle between each incident light beam and the main surface is 45 degrees. The main surface is such that the inspection light reflected from the main surface is transmitted to a second detector 6.
It is inclined to progress to.

Therefore, the test light emitted from the test light light source 10 partially enters the transmitting mirror 15, and the test light is transmitted through the partially transmitting mirror 15, and the test light enters the second detector 7. It is separated into the inspection light which is reflected and enters the second end face 2b of the optical fiber 2. The inspection light incident on the second end surface 2b travels through the interior covered by the side surface, exits from the first end surface 2a, and further passes through the condenser lens 4, after which it is reflected by the - part transmission mirror 14. and enters the first detector 6. In this way, the amount of light that is received before and after passing through the optical fiber 2 can be detected by the second detector and the first detector, respectively. Similar to the laser device of the first embodiment, the detected signal is compared with the reference signal in the comparison means 8, and in response to a command from the comparison result, the control means 9 controls the processing laser light source 1 to produce a processing laser beam. In this way, in the laser device of this embodiment, as well as in the laser device of the first embodiment, when the optical fiber 2 deviates from the reference state, In this case, the processing laser light source 1 becomes unable to emit processing laser light, so it is necessary to prevent the processing laser light from leaking from the optical fiber 2 to the outside and to prevent the optical fiber 2 from deteriorating due to the absorber attached to the end face of the optical fiber 2. I can do it.

In addition, as described above, both the laser devices shown in the first and second embodiments can ensure high safety in operating the laser device, and are superior to conventional Rayleigh devices in terms of maintaining the optical fiber. The effect of being able to have an advantage can be obtained. Furthermore, the Rayleigh apparatus of the first and second embodiments includes a light source 20 for guide light in addition to a processing laser light source and an inspection light source, and a workpiece is placed between the optical fiber 2 and the workpiece 3. Partly transmitting mirrors 13 and 15 are arranged to prevent the inspection light from proceeding.
By turning off the guide light light source when alignment 1~ for the workpiece 3 is completed, only the processing laser light reaches the processing location 3a during the process of processing the workpiece 3 with the processing laser light. . This means that, for example, when this laser device is used for treatment in the medical field, the guide light and inspection light, which are visible light that can be an eyesore for patients or surgeons, do not enter the visual field during treatment, so treatment can be performed smoothly. It also has the effect of being able to. Furthermore, as is clear from the comparison of the laser devices of the first and second embodiments, since an independent inspection light source is used separately from the processing laser light source, the inspection light source is used as the first and second light source of the optical fiber. Since it can be placed on either side of the end face of the laser device, it is possible to have a high degree of freedom in designing the laser device.

Other aspects of the constituent elements adopted in the first and second embodiments will be described below.

First, regarding the first and second detectors, in order to improve the accuracy of the detection signal, two detectors were used to detect the amount of test light before and after passing through the optical fiber.
Since the state of the optical fiber can be identified based on the fluctuation in the amount of the test light that has passed through the optical fiber, if priority is given to simplifying the structure of the laser device, a detector that detects the test light that has passed through the optical fiber is recommended. may be used only. Also, if a detector is not installed to detect the amount of inspection light before it passes through the optical fiber,
As in the first and second embodiments, the inspection light from the inspection light source 10 is partially transmitted to the second detector by the transmitting mirror 13.15.
Since there is no need to separate the inspection light that covers the optical fiber and the inspection light that passes through the optical fiber, the partially transmitting mirror 12.15 is not used and is opposed to either the first or second end surface of the optical fiber 2, Moreover, it is also easy to arrange the inspection light source 10 in a direction different from the optical axis of the processing laser beam and the guide light, and to make the inspection light directly enter the end face of the optical fiber 2 from this inspection light light source 10. obtain. Further, as a means for detecting the amount of the inspection light after passing through the optical fiber 2, a partially transmitting mirror 13, 14 is installed in the optical path of the processing laser beam and the guide light to separate the inspection light from the processing laser beam. However, without using a partially transmitting mirror like that shown in A, for example, it is possible to transmit the wavelength component of the inspection light to the surface facing the optical fan 1 of the condenser lens placed outside both end faces of the optical fiber. By forming a reflective film and arranging a detector in the traveling direction of the inspection light reflected by the film, the optical fiber 2
The amount of inspection light after passing through may be detected.

Further, as a similar device, a condensing lens 5 that condenses the processing laser beam onto the workpiece is usually disposed on a holder such as a hand piece or a probe that supports and accommodates the peripheral portion of the condensing lens 5. Therefore, it is also possible to detect the inspection light reflected by the portion of the holder that holds the peripheral edge of the condensing lens using a detector.

Next, in the processing laser light source, Nd:YAG may be used as a laser medium instead of Er:YAG, or
You may also use a Ruby Rayli or Areclean dry mill laser. In this case, when using these laser beams, it is preferable to use a quartz fiber as the optical fiber, which has low absorption for any of the oscillated laser beams. Can be used.

Also, as in Example 1 and Example 2 above, Er:YAG
When E r is used as a laser medium, in order to suppress the absorption to the oscillation wavelength of YAG, the material for the optical fiber is Zaphire, and the material for the condensing lens is 7n 3 e. Alternatively, Ca U 2 etc. can be suitably used.

Furthermore, as a control means, if it is possible to control the processing laser light source to a state in which the processing laser light can be emitted or not emitted, the drive circuit for controlling the laser oscillation can be electrically cut off. Alternatively, the processing laser light source may be controlled in conjunction.

Also, as a light source for inspection light, the inspection light emitted by it will not deviate from the reference state of the optical fiber! No output,
Alternatively, it is preferable to use a wavelength band that does not overlap with the absorption wavelength band of the optical fiber. For example, use a light emitting diode, etc.
can be done.

[Effects of the Invention] Since the laser device of the present invention is equipped with a light source for inspection light separately from a light source for processing laser, the process of adding J: Relay 1f to processing laser light is different from the original. It is possible to detect the state of the optical fiber even before the processing laser beam is emitted, and based on this detection result, if the optical fiber deviates from the standard state, it is possible to change the processing laser beam of the processing laser light source. Since the state is made such that the laser beam cannot be emitted, it is possible to prevent the processing laser beam from being emitted to an optical fiber that deviates from the reference state. This provides a high degree of safety when operating the laser device. Furthermore, since the inspection light that does not contribute to laser processing is used as the light source for inspection light, deterioration of the optical fiber due to the inspection light can be prevented in the process of inspecting the condition of the optical fiber. This can contribute to the preservation of optical fibers.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a laser device according to a first embodiment of the present invention, FIG. 2 is a configuration diagram of a laser device according to a second embodiment of the present invention, and FIG. 3 is a configuration diagram of a conventional laser device. It is. 1... Light source for processing laser, 2... Optical fiber 2a.
...First end face, 2b... Second end face, 3... Workpiece, 6... First detector, 7... Second detector, 8... Comparison means , 9...control means. Patent applicant Hoya Co., Ltd.

Claims (1)

[Scope of Claims] A processing laser light source, and an optical fiber that guides a processing laser beam emitted from the processing laser light source from a first end face to a second end face, A laser device that performs laser processing on an optical fiber, comprising: an inspection light light source that emits an inspection light that does not contribute to the laser processing to one of the first and second end surfaces of the optical fiber; and the other end surface of the optical fiber. a detector that detects the test light emitted from the end face of the detector; and among the detection signals obtained by the detector, the detection signal of the test light that has passed through the optical fiber in a reference state is set as a reference signal in advance, and this reference signal is set in advance as a reference signal. and a comparison means for comparing the detection signal of the inspection light obtained during the inspection of the optical fiber; and in response to the comparison result obtained by the comparison means, the processing laser light source is set to a state in which the processing laser light can be emitted; 1. A laser device comprising: a control means for controlling the laser device so that it is in a state where it cannot emit light.