A laser alignment system is used to align an output fiber with a fiber laser, for example, when coupling a feeding fiber to a process fiber using a beam coupler or switch. The alignment system includes a laser alignment apparatus that is coupled at a first end to the output fiber and at a second end to a beam dump/power meter. The alignment apparatus defines a light passage and a light capture chamber along the light passage. When light is not aligned into the core of the output fiber, at least a portion of the light passing out of the output fiber will be captured by the light capture chamber and detected by a photodetector in optical communication with the light capture chamber. By monitoring the readings of the photodetector, the output fiber may be properly aligned with the laser light from the fiber laser.

There is provided a laser processing device that includes a laser light source configured to output laser light, a spatial light modulator configured to modulate the laser light output from the laser light source according to a phase pattern and emit the modulated laser light, an objective lens configured to converge the laser light emitted from the spatial light modulator onto an object, a controller configured to control a phase pattern to be displayed on the spatial light modulator, and a determiner configured to determine whether operation of the spatial light modulator is normal, in which the controller performs switching control in which the phase pattern to be displayed on the spatial light modulator is switched, and the determiner makes the determination on the basis of a change in intensity of the laser light emitted from the spatial light modulator between before the switching control and after the switching control.

A machine learning device is connected to a fiber laser device. The machine learning device observes, as a state variable representing a driving state of the fiber laser device, a state quantity including time-series data on output light detection results obtained by detecting a light output of laser light emitted from the fiber laser device and time-series data on reflected light detection results obtained by detecting reflected light of the laser light, and acquires determination data representing a failure occurrence situation in the fiber laser device as determined from a difference between the output light detection results and a light output instruction of the fiber laser device. The machine learning device learns a boundary condition for failure occurrence caused by the reflected light by using the state variable and the determination data.

A laser oscillator capable of detecting scattered light intensity when a laser beam is incident on an end surface of a fiber more appropriately is provided. A laser oscillator monitoring control system includes: a scattered light detection unit that detects a scattered light intensity on an input end surface of a process fiber of a fiber laser oscillator; a control unit that controls a laser output value on the basis of a laser output command value from a CNC and a detection result obtained by the scattered light detection unit; a normal scattered light calculation unit that calculates a normal index value; a first threshold setting unit that sets a first threshold indicating an abnormality resulting from a contamination and/or a scratch; a second threshold setting unit that sets a second threshold indicating an abnormality resulting from an optical axis shift; and a third threshold setting unit that sets a third threshold indicating an abnormality of a level in which a component is destroyed. The control unit controls a laser output value on the basis of the scattered light intensity detected by the scattered light detection unit, the first threshold, the second threshold, and the third threshold.

An optical inspection device designed for testing an optical component such as a protective glass, an optical transmission system of a welding laser beam having a laser wavelength, comprising: a light source designed to emit a test light, receiving means designed to receive at least a portion of the test light and to quantify at least one quantity of the received light, means for holding the optical component designed to position the optical component between the light source and the receiving means, characterized in that: the portion of the test light received by the receiving means has a wavelength at ±20% of the laser wavelength.

A laser processing apparatus includes a laser beam applying unit, an imaging unit, and a processing section. The processing unit includes a histogram generating section and a determining section. The histogram generating section generates, from an image obtained by the imaging unit imaging a plurality of processing marks formed by applying the laser beam from the laser beam applying unit to a one-surface side of the workpiece, a first histogram including a plurality of first positions along a first direction of the image and brightness at each of the first positions and a second histogram including a plurality of second positions along a second direction orthogonal to the first direction and brightness at each of the second positions. The determining section determines a boundary of each region where one of the processing marks is formed, based on the first histogram and the second histogram generated by the histogram generating section.

A laser processing apparatus includes a laser oscillator; a processing head; a driver that controls a relative positional relationship between a workpiece and the processing head; control circuitry that controls the laser oscillator and the driver in order for the laser beam to scan a processing path on the workpiece; detection circuitry that observes a state of the workpiece being processed and outputs a result of observation as a time series signal; processed state observation circuitry that obtains evaluation information including a determination result that indicates whether a processed state of the workpiece is satisfactory or defective by evaluating the processed state of the workpiece on the basis of the time series signal for each of a plurality of sections obtained by dividing the processing path; and estimation circuitry that estimates a cause of a defect on the basis of the evaluation information of two or more of the sections.

Monitoring of protective glasses (8) in laser machining heads, which are exposed to dust, sputtering and/or soiling, with the aim of predicting the contamination of the protective glass. For this purpose, image sections (19) are captured by means of at least two image capture systems (16) at capture-times, computer-readable image files are stored by means of a frequency-based compression algorithm, and a file size value (kB) is determined for each image file on the basis of its file size. A signal is generated if for a majority of the image capture systems (16) the file size values (kB) decrease and/or are below one of a predefined number of threshold values (20) for a predetermined minimum number of consecutive capture-times.

A cutting device for a thin semiconductor wafer includes a laser light generator and a polygonal mirror structure. The laser light generator is used to provide a femtosecond laser light with a pulse width on a femtosecond order (10.sup.−15 second). The polygonal mirror structure is used to reflect the femtosecond laser light. The polygonal mirror structure has a plurality of reflective surfaces. The polygonal mirror structure rotates continuously with respect to the femtosecond laser light, such that the femtosecond laser light is sequentially and repeatedly reflected by the plurality of reflective surfaces and projected on a semiconductor wafer. The femtosecond laser light projected on a semiconductor wafer moves repeatedly along a same predetermined direction in a predetermined range during a predetermined time to groove or cut the semiconductor wafer.

A first detector detects an output of a reflected beam from an exit end surface of a first parallel plate. A determination unit determines that an abnormality occurs in the first parallel plate when the detection value of the first detector is smaller than a predetermined determination threshold.