摘要:
In a laser welding, a laser beam is focused on a workpiece by a focusing lens or lenses. The focusing lens or lenses image an aperture liming the size of the laser beam on the workpiece and the size of focused laser beam is the image size of the aperture on the workpiece at the wavelength of the laser. A weld pool is generated by the interaction of the focused laser beam and the workpiece. Due to the thermal conduction of the workpiece, the size of the weld pool is generally not the same as the size of the focused laser beam and varies with the power of the laser or with the focus shift of the focusing lens or lenses. The weld pool irradiates a thermal radiation. The thermal radiation is measured back through the focusing lens or lenses and through the aperture limiting the size of the laser beam or any other aperture limiting a size of the thermal radiation to be measured in three spectral bands with single element detectors. Due to the chromatic aberration of the focusing lens or lenses, the transmittance of each spectral band of the thermal radiation varies with the size variation and with the focus position of a weld pool and the spectral band signals measured with single-element detectors vary if the size and/or the focus position of a weld pool varies. However, the chromatic aberration of the focusing lens or lenses is usually unknown and is not easy to measure. A method to monitor the size variation and/or the focus position of a weld pool is disclosed wherein the effects of the chromatic aberration are measured experimentally and the size variation of a weld pool is monitored independently from the focus shift of the focusing lens or lenses and the focus position of a weld pool is monitored independently from the power variation of the laser.
摘要:
In a laser welding, a laser beam is focused on a workpiece by a focusing lens or lenses. The focusing lens or lenses image an aperture liming the size of the laser beam on the workpiece and the size of focused laser beam is the image size of the aperture on the workpiece at the wavelength of the laser. A weld pool is generated by the interaction of the focused laser beam and the workpiece. Due to the thermal conduction of the workpiece, the size of the weld pool is generally not the same as the size of the focused laser beam and varies with the power of the laser or with the focus shift of the focusing lens or lenses. The weld pool radiates a thermal radiation. An apparatus and method is disclosed wherein the thermal radiation is measured back through the focusing lens or lenses and through the aperture limiting the size of the laser beam or any other aperture limiting a size of the thermal radiation to be measured in at least three spectral bands with single element detectors. Due to the chromatic aberration of the focusing lens or lenses, the transmittance of each spectral band of the thermal radiation varies with the size variation and with the focus position of a weld pool and the spectral band signals measured with single-element detectors vary if the size and/or the focus position of a weld pool varies. Algorithm to monitor the size variation and/or the focus position of a weld pool is disclosed wherein the size variation of a weld pool is monitored independently from the focus shift of the focusing lens or lenses and the focus position of a weld pool is monitored independently from the power variation of the laser.
摘要:
A mobile terminal is provided including a battery, an output unit, a memory, and a controller. The battery provides power. The output unit outputs a wireless recharge state. The memory stores recharge menus and recharge menu settings. The controller provides recharge menus for wireless recharging of the battery based on whether payment is required for the wireless recharging. The controller also performs a wireless recharging operation according to selection of the recharge menu settings.
摘要:
A mobile terminal is provided including a battery, an output unit, a memory, and a controller. The battery provides power. The output unit outputs a wireless recharge state. The memory stores recharge menus and recharge menu settings. The controller provides recharge menus for wireless recharging of the battery based on whether payment is required for the wireless recharging. The controller also performs a wireless recharging operation according to selection of the recharge menu settings.
摘要:
A method and apparatus for real-time weld process monitoring are provided for a pulsed laser welding. The thermal radiation from a weld pool is measured at several spectral bands through an aperture with single-element detectors after splitting the spectral bands with dichromatic mirrors and beam splitters. The distal end of an optical fiber for laser delivery can be used as an aperture and each spectral band signal is measured with a single-element detector. Due to the chromatic aberration of an imaging optics, the field of view from a single-element detector through the aperture is varied by the wavelength of spectral band. The weld pool size contributing to the spectral band signal varies by the wavelength of the spectral band. The transmittance profile of each spectral band also depends on the focus shift of imaging optics. By processing the measured spectral band signals, the size of a weld pool, the power variation on a workpiece and the focus shift of imaging optics can be monitored simultaneously. Furthermore, the weld pool sizes at predetermined positions in time are correlated to the weld depth and the weld defect such as a weld gap for weld quality assurance.