JPS62136085A - Laser irradiation apparatus - Google Patents

Abstract

PURPOSE:To detect securely the deterioration of an optical fiber cable and the abnormality when the optical fiber is burnt and facilitate monitoring and checking the characteristics of a power sensor by a method wherein the resistance value of the power sensor is measured at the time of initial operation and at the time when a laser beam is not emitted and compared with a reference value. CONSTITUTION:An analog switch 8 is so controlled as to put the output of a power sensor 2 into a voltage dividing resistance 9 and a comparator 10 and a voltage A corresponding to the resistance of the power sensor 2 is compared with the reference voltage B of a reference voltage source 11 at the time of initial operation and at the time when a laser beam is not emitted. If A<B, the apparatus can be operated and, if A>B, a central control circuit 6 transmits a signal to an alarm indicator 15 in accordance with the comparison signal and the indicator 15 gives an alarm or abnormality indication or stops the apparatus. When the laser beam is emitted, the analog switch 8 is changed over to the opposite porality and the voltage A is amplified by an amplifier 12 and the output C of the amplifier 12 is compared with the reference voltage D of a reference voltage source 14. If C<D, the apparatus can be operated and, if C>D, the central control circuit 6 receives the output signal and the alarm indicator 15 gives an alarm or abnormality indication or stops the operation of the apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a laser irradiation device equipped with an optical fiber cable, and more specifically to a configuration for detecting an abnormality in the optical fiber cable of the same device. Conventional technology In recent years, the scope of application of laser irradiation equipment has been expanding more and more, and there is a demand for equipment that is smaller, lighter, and easier to use.In particular, for laser scalpels, etc., the optical cable that guides the laser beam to the irradiation point has not been used in the past. Instead of a mirror-articulated optical cable that reflects the laser beam with a mirror, an optical fiber cable that guides the laser beam to the irradiation point using an optical fiber is now being used. Not only laser light, but also 106 μm of Co2 laser
It has become possible to transmit far-infrared laser light, and as a result, optical cables have become thinner, more flexible, and easier to operate.

Problems to be Solved by the Invention However, along with this, absorption and scattering of laser light during laser transmission and emission of the optical fiber cable, and furthermore, a decrease in transmission efficiency due to an increase in end face reflected light, etc., and when abnormalities such as melting and burning occur. Reliable detection of these, reliable power sensors for detecting them, and checking the reliability of the power sensors are major issues.

In order to solve the above problems, the laser irradiation device of the present invention is equipped with a power sensor consisting of a thermocouple group at the input end or the output end of the optical fiber cable, and the power sensor is provided during initial operation and when the laser beam is not emitted. It is equipped with an abnormality detection circuit and a central control unit that measure the resistance value of the power sensor and compare it with a reference value, and measure the output of the power sensor when emitting laser light and compare it with the reference value. The device is equipped with an alarm display unit that displays an alarm 9 when the alarm is off.

Effect: By the above means, the resistance value of the power sensor is compared with the reference value, and when an abnormality occurs, a judgment is made based on the fact that the resistance value deviates from the reference value, and the alarm display section can notify that the abnormal state is present.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an example of an implementation configuration according to the present invention.

In the figure, 1 is an optical fiber cable, 2 (-1 is a power sensor consisting of a group of thermocouples that detects abnormalities in the cable, 3 is a beam shutter that controls the incidence of laser light into the optical fiber cable 1, and 4 is a sensor such as CO2). A gas laser oscillator, 5 a high-voltage power supply that excites the discharge, 6 a central control unit that controls the entire device, 7 an internal analog switch 8 for detecting the output from the power sensor 2 and determining whether it is good or bad, and a voltage divider. An optical fiber abnormality detection circuit includes a resistor 9, comparators 10 and 13, reference voltage sources jl and 14, an amplifier 12, etc., and 15 is an alarm display unit that issues an alarm and displays an alarm in the event of an abnormality. The sensor 2 detects the reflected light of the laser beam at the input end of the optical fiber cable 1. Under normal conditions, the reflected light is small and the output level is low, but if the end face deteriorates or an abnormality such as melting occurs, it may spread. The angle of reflected light increases,
The output increases and can be detected, and since the configuration consists of a group of thermocouples, it usually exhibits a constant resistance value of about 10 to 42 ohms. First, the analog switch 8 is controlled by the central control unit 6 so that the output of the liquid power sensor 2 enters the voltage dividing resistor 9 and the comparator 10 during the initial operation of the device and when the laser is not emitted with the beam shiner 3 closed. Compare the voltage value A corresponding to the resistance value of 2 with the reference voltage B of the reference voltage source 11, which is set in advance to a voltage value directly corresponding to the resistance f of the power sensor 2 at the time of an abnormality, and if A<B. For example, the comparator output can be used at rLJ, and A
>B, the comparator 10 immediately outputs the "rH" signal, and the central control circuit 6 uses that signal to turn on the alarm display section 16.
The system sends a signal to the system to display alarms and abnormalities, and may also stop the equipment. Also, when emitting a laser, the analog switch 8 is switched to the opposite direction, the output is amplified by the amplifier 12, and the output value C is compared by the comparator 13 to the power sensor output at the time of abnormality in advance. A comparison is made with a reference voltage source 140 set to a corresponding voltage value,
When C<D, the output of the comparator 13 can be used at rLJ, and when C>D, the rH'' signal of the comparator 13 is output as described above, and the central control circuit 6 receives the output signal, and ≦ The information display unit 15 performs warnings, abnormality display, or device operation stoppage.

Further, the present invention is similarly applicable to a configuration in which the power sensor 2 is attached to the output end of the optical fiber cable 1 and detects a part of the laser light emitted from the optical fiber cable 1, but in this case, j. In the event of an abnormality such as loss of optical fiber cable, the output of the power sensor 2 becomes small, so the comparison condition is that C>D is normal, and C (D is abnormal).

Effects of the Invention As described above, according to the present invention, abnormalities such as deterioration and burnout of optical fiber cables can always be reliably detected, and the power sensor system is also improved because the unexamined patent application of the power sensor that detects the same is constantly monitored and checked. This makes it possible to create a highly reliable optical fiber cable anomaly detection system that is free from detection errors.

[Brief explanation of drawings]

The figure is a circuit diagram of a laser irradiation device showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Optical fiber cable, 2... Power sensor, 4... Laser oscillator, 6... Central control unit, 7... Abnormality detection circuit, 15...・・・・・・
Alarm display section.

Claims (1)

[Claims] In a laser irradiation device equipped with a power sensor consisting of a group of thermocouples or the like at the input end or output end of an optical fiber cable, the resistance value of the power sensor is measured during initial operation and when laser light is not emitted, and compared with a reference value. , and includes an abnormality detection circuit and a central control unit that measure the output of the power sensor and compare it with a reference value when emitting laser light,
A laser irradiation device equipped with an alarm display unit that issues an abnormality alarm and an abnormality display when both values deviate from standard values.