JPH05115569A - Laser device - Google Patents

Abstract

PURPOSE:To provide precise irradiating time and total irradiating energy of laser beam by opening a laser beam shielding means at the time of judging that the output value of laser beam reaches a set output value by the use of a comparing means to start the integrating operation of a set irradiating time together with the emission start. CONSTITUTION:Emission data is preliminarily inputted to a control part 3 by an output setting part 8 and an emitting time setting part 9. A laser source 2 supplies a power to a laser oscillator 1 according to the signal from the control part 3 to emit a laser beam from an emitting mirror 4. The beam is divided into two by a beam splitter 13, one beam is measured by an optical measuring equipment 14 and the beam output is compared with a set output in a comparator 15. When it is judged that the beam output reaches the set output, the signal of shutter open is transmitted to an emitting shutter driving part 16 to open an emitting shutter 12. Further, a timer in the control part 3 is started and the emission of the laser beam is continued for a required set time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device for treating a living body with laser light, for example.

[0002]

2. Description of the Related Art A general laser device has a laser power source controlled by a control unit and a laser oscillator driven by the laser power source. A foot switch and an output setting unit are provided for the control unit. A signal from the emission time setting unit is input. The shutter drive unit is controlled by the control unit, whereby the resonator shutter is opened and laser light is emitted.

Japanese Patent Laid-Open No. 1-197085 discloses that
A method of feedback controlling the laser power is shown. This control is to detect and control the laser output so that the laser output becomes constant.

[0004]

Normally, in this type of laser device, when the foot switch is not stepped on, the heat generation of the laser oscillator is kept low, so the input from the power source to the laser oscillator is kept small. Since the current value input to the laser oscillator is increased after stepping on the foot switch, the laser output value is low at the beginning of laser light, gradually approaches the required value, and reaches the required value only after a certain time. ..

That is, there is a rise time from the start of the laser light emission to the required laser output value. Due to this time lag, the actual laser light emission time is shorter than the set value, or As a result, the emitted energy may be low.

By the way, in PDT, for example, in which a drug having tumor affinity is administered to treat cancer, it is particularly important to control the total irradiation energy amount of laser light. Therefore, it is desired to provide a laser device capable of accurately emitting a laser beam having a set output for a set time.

The present invention has been made in view of the above problems, and an object thereof is to provide a laser device capable of accurately emitting a laser beam having a set output value for a set time. is there.

[0008]

In the laser device of the present invention, the laser oscillator drives the laser oscillator by the laser power source controlled by the control unit having the output setting unit, and the laser oscillator tries to emit the laser beam. Laser beam blocking means for blocking the laser beam to prevent the start of laser beam emission, means for detecting the output value of the laser output by the laser oscillator, output value of the detected laser and output set by the output setting section And a means for comparing with the value, and when it is determined that the output value of the laser beam to be emitted by the laser oscillator has reached the set output value based on the result of the comparison, the laser beam blocking means is opened and set together with the start of emission. And a control means for starting the emission operation of the irradiation time.

In this way, the output level of the laser beam is detected, and when it reaches the set value, the shutter for emitting the laser is opened, and the emission time is measured from the time when the final shutter is opened. Therefore, accurate irradiation time and total irradiation energy of the laser light can be obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A laser device according to an embodiment of the present invention will be described below with reference to the drawings. This laser device has a laser oscillator 1, and this laser oscillator 1 is driven by a laser power supply 2. It is controlled by the control unit 3 by the laser power supply 2. The laser oscillator 1 is composed of, for example, a laser rod excited by an excitation lamp, and an emission mirror 4 and a total reflection mirror 5 as a resonance mirror and a resonator shutter 6 are provided on the axis of the laser rod.

Signals from the foot switch 7, the output setting unit 8 and the emission time setting unit 9 are input to the control unit 3. Further, the control unit 3 drives the shutter drive unit 11, whereby the resonator shutter 6 is opened and the laser light emission operation is performed.

On the optical axis of the laser beam emitted from the emission mirror 4, an emission shutter 12 as a laser beam interruption means for interrupting the laser beam which the laser oscillator 1 is about to emit and suppressing the emission start of the laser light. Is provided. A beam splitter 13 is arranged in front of the emission shutter 12. One of the laser beams divided by the beam splitter 13 is emitted as a treatment laser beam and becomes output energy when the emission shutter 12 is opened, and the beam splitter 1
The other laser beam divided by 3 is incident on the photodetector 14. That is, it constitutes a means for detecting the output value of the output energy emitted from the laser oscillator 1 as the treatment laser light.

The photodetector 14 detects information about the laser output and sends this information to the comparator 15. Here, the comparator 15 compares the actual laser output value with the output level set by the controller 3.
Further, the output of the comparator 15 is sent to the emission shutter drive unit 16 that opens the emission shutter 12 and the control unit 3.

Next, the operation of this laser device will be described. First, the output setting unit 8 and the emission time setting unit 9 input the emission data to the control unit 3 in advance. When the foot switch 7 is turned on, the laser power supply 2 is supplied with electric power for oscillating the laser oscillator 1 by a signal from the control unit 3 and, at the same time, an opening operation signal is sent to the shutter drive unit 11. 11 opens the resonator shutter 6.

As a result, the emission mirror 4 and the total reflection mirror 5
Then, laser excitation is performed and a laser beam is emitted from the emission mirror 4. This laser beam is split into two by the beam splitter 13, and the output of one beam is measured by the photodetector 14 and the output of the laser beam is converted.

In the comparator 15, the output of the laser beam detected by the photodetector 14 is compared with a preset output level, and it is judged that the output of the laser beam has reached the set output. In this case, a signal for opening the shutter is sent to the emission shutter drive unit 16 to output the emission shutter 1
Open two. As a result, laser light is emitted. Further, regarding the emission time, the timer in the control unit 3 is started from the time when the shutter open signal is sent from the comparator 15 to the control unit 3, and the emission of the laser light is continued for a required set time.

Therefore, the control unit 3 is linked with the comparator 15.
Detects the actual output power of the laser beam from the laser oscillator 1, and when the output power reaches a set output, the output shutter 12 is opened and the timer starts counting the output time, so that the set predetermined time is set. It is possible to perform laser emission with an accurate energy amount at a level output. In this embodiment, both the resonator shutter 6 and the emission shutter 12 are closed when the emission is stopped for safety.

FIG. 3 shows a modification of the laser oscillator. This laser oscillator is a solid-state laser excited by a semiconductor laser, which is a system that can be miniaturized. This is L
Although D is used, the wavelength of the LD has an advantage that a laser can be efficiently oscillated. However, there is a drawback in that the output of the LD itself is small and a large output cannot be obtained because it is excited by the LD instead of the excitation lamp.

Therefore, in order to obtain a large output, many LDs are often used. FIG. 3 shows an example of a YAG laser device of multi-facet excitation type. One plate N
A large number of incident lenses 22 are arranged around the d: YAG crystal rod 21, and the LD beam from each of the incident lenses 22 is passed through the reflection point of the Nd: YAG crystal rod 21 and coaxially with the oscillation beam in the laser medium. It is designed to be incident on. An LD beam is transmitted from an LD light source device 24 to each incident lens 22 through an optical fiber 23. An emission mirror 25 is provided on the emission end side of the Nd: YAG crystal rod 21, and a total reflection mirror 26 is provided on the other end side of the Nd: YAG crystal rod 21.

In this system, the number of LDs that can be made incident on the Nd: YAG crystal rod 21 through its reflection point is limited, but the one shown in FIG.
The YAG crystal rod 21 is divided into a plurality of parts to increase the number of LDs that can be made incident through the reflection points. That is, the plurality of plate-shaped Nd: YAG crystal rods 21a and 21b are arranged in a zigzag shape at a angle β equal to the beam propagation angle α. Then, by making the shapes of the Nd: YAG crystal rods 21a and 21b the same, the emission mirror 25 and the total reflection mirror 26 have the same axis, which facilitates the optical adjustment thereof.

Further, in this case, any number of Nd: YAG crystal rods 21a, 21b, ... May be arranged, but in order to make the emission mirror 25 and the total reflection mirror 26 have the same axis, 2 × n.
It is preferable that the number is n (n is an integer). Like this Nd: YA
By arranging the G crystal rods 21a, 21b, ... In a zigzag manner, a compact and high-power LD-excited YAG
A laser is obtained.

FIG. 5 shows an example of using this laser device in laparoscopic surgery. A laser probe 31 is inserted into the body cavity 32 from the laser device 30. The laser probe 31 is provided with an air supply passage 34 for cooling the tip 33, and carbon dioxide gas, for example, is sent from the air supply gas cylinder 35 through the valve 36 through the air supply passage 34. After cooling 33, it flows into the body cavity 32.

A pneumoperitoneum 37 is inserted into the body cavity 32 for the purpose of inflating the body cavity 32. The pneumoperitoneum 37 is connected to the pneumoperitoneum 39 through the air supply conduit system 38. Therefore, the internal pressure of the body cavity 32 is maintained at a predetermined constant pressure set in advance.

Further, the conduit system 38 of the pneumoperitoneum 37 has a pressure regulating valve 41 and a pressure sensor 42, and the pressure sensor 42
The information on the pressure value detected in (4) is sent to the control unit 43. When the detected pressure value is equal to or higher than the set value, a signal is sent to the pressure regulating valve 41 and the laser device 30, and the pressure regulating valve 41 is opened until the pressure falls to the set value, and the valve 36 is further opened. Is closed to stop the air supply from the air supply gas cylinder 35 to the air supply passage 34 of the laser probe 31. During this period, if the laser is output, the laser probe 31 will be overheated, so the output of the laser device 30 is stopped. In this embodiment, it is also effective to dispose the pressure regulating valve 41 and the pressure sensor 42 in the conduit system of the laser probe 31.

Here, in a pneumoperitoneum system that has a laser probe 31 that guides the laser light generated by the laser device 30 into the body cavity 32, the gas pressure in the body cavity is measured. A pressure sensor 42 is provided, and the pressure sensor 42 can control at least three of a valve 36 that releases gas in the body cavity according to the signal, air supply from the laser probe 31, and laser oscillation of the laser device 30. Since it is configured such that the internal pressure of the body cavity 32 can be kept constant.

FIG. 6 shows a laser device 50 having a laser oscillator 51, a power supply 52 and a controller 53, to which a laser probe 54 is connected. This laser probe 54 has a contact sensor 55 over its entire length, as shown in FIG. The contact sensor 55 is used to detect the tightening pressure from a rubber cap or the like to detect the usage status and use the laser probe 54 safely when the laser probe 54 is inserted into an endoscope or a trocar.

The signal detected by the contact sensor 55 is input to the control unit 53 of the laser device 50, and it is determined that the laser probe 54 is in use. Then, the mounting state is determined, and the laser oscillation is performed when a signal from the foot switch 56 is received. Therefore, even if the foot switch 56 is erroneously operated, the laser probe 54 does not emit light unless it is in use. FIG. 8 shows such a contact sensor 55.
The number is increased to a plurality, such as above and below, and the detection is performed more reliably.

FIG. 9 shows that when the tip of the laser probe 54 projects from the tip of the endoscope, the contact sensor 57 is arranged only at the position where the tightening rubber cap comes, and laser irradiation can be performed only at the projected position. It is the one.

FIG. 10 shows an example of a laser probe for surgery that does not pass through an endoscope or the like. A contact sensor 58 is arranged at the grip portion of the handpiece 61 so that the laser is emitted only when the operator grips the handpiece 61. It is possible to emit light.

FIG. 11 shows a modification of the tip of the flexible laser probe. A cylindrical metal tip 73 is fixedly attached to one end of the Teflon sheath 72 for accommodating the optical fiber 71, that is, the emitting end, and a threaded portion formed on the inner diameter of the inner end of the metal tip 73. The outer circumference of the optical fiber 71 is attached to the optical fiber 74. The outer circumference of the optical fiber 71 is provided with a resin coating. Further, the distal end of the sheath 72 is fitted and fixed to the outer periphery of the base end of the metal tip 73. Installed over the entire length of the optical fiber.

FIG. 11 shows the sheath 72 made of Teflon over the entire length. However, as shown in FIG. 12, only the tip portion is changed to a flexible tube 75 made of silicon or the like, and the flexible tube 75 is provided with the above-mentioned tip at the distal end. Attach the metal tip 73. That is, a fixed length portion from the metal tip 73 is formed on the front end side of the optical fiber 71 by the flexible tube 75, and a portion behind the flexible tube 75 is a sheath 72 made of Teflon.

By doing so, it is possible to make the vicinity of the tip, which is particularly required to be flexible, soft. As described above, it is possible to easily operate the angle of the endoscope while being inserted in the channel of the endoscope, as compared with the case where the entire length is formed of the Teflon tube. Flexible tube 7
Since 5 is a silicon-based resin, its heat resistance can be improved.

Further, when a soft material such as a silicon tube is used, expansion and contraction in the length direction can be absorbed, so that even when the entire laser probe is wrapped around and stored, it is impossible to fix both ends of the optical fiber. Need not be added, and its operability can be improved.

[0034]

As described above, according to the present invention, the output level of laser light is detected, and when it reaches the set value, the shutter for emitting the laser is opened, and the emission time is finally measured. Perform from the point when the shutter is opened. Therefore, accurate irradiation time of laser light and total irradiation energy can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration of a laser device according to an embodiment of the present invention.

FIG. 2 is a graph showing a characteristic of a laser output emitted from the laser device.

FIG. 3 is a schematic configuration diagram showing a modified example of a laser oscillator in a laser device.

FIG. 4 is a schematic configuration diagram showing another modification of the laser oscillator of the laser device.

FIG. 5 is a diagram showing the configuration of a system when the laser device is used in laparoscopic surgery.

FIG. 6 is an explanatory diagram of a schematic configuration of a pneumoperitoneum device of a laser device.

7A is a front view of the laser probe, and FIG. 7B is a side view of the laser probe.

8A is a front view of the laser probe, and FIG. 8B is a side view of the laser probe.

FIG. 9 is a side view of the laser probe.

FIG. 10 is a side view of the laser probe.

FIG. 11 is a cross-sectional view of the tip of the laser probe.

FIG. 12 is a cross-sectional view of the tip of the laser probe.

[Explanation of symbols]

1 ... Laser oscillator, 2 ... Laser power supply, 3 ... Control unit,
7 ... Foot switch, 8 ... Output setting unit, 9 ... Ejection time setting unit, 11 ... Shutter drive unit, 12 ... Ejection shutter, 1
3 ... Beam splitter, 14 ... Photodetector, 15 ... Comparator, 16 ... Ejection shutter drive section.

[Procedure amendment]

[Submission date] February 5, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

A laser device according to an embodiment of the present invention will be described below with reference to the drawings. This laser device has a laser oscillator 1, and this laser oscillator 1 is driven by a laser power supply 2. The laser power supply 2 is controlled by the control unit 3. The laser oscillator 1 is composed of, for example, a laser rod excited by an excitation lamp, and an emission mirror 4 and a total reflection mirror 5 as a resonance mirror and a resonator shutter 6 are provided on the axis of the laser rod.

Claims (1)

[Claims] 1. A laser device for driving a laser oscillator by a laser power source controlled by a control unit having an output setting unit, wherein a laser beam which is to be emitted by the laser oscillator is cut off to suppress emission start of laser light. Beam blocking means, means for detecting the output value of the laser output by the laser oscillator, means for comparing the detected output value of the laser with the output value set by the output setting section, and the result of the comparison And a control means for opening the laser beam cutoff means and starting an integration operation of the set irradiation time with the start of the emission when it is determined that the output value of the laser beam to be emitted by the laser oscillator has reached the set output value. A laser device characterized by the above.