This laser irradiation mechanism includes a control unit which has a function allowing the focal point of a laser beam to describe a circle, performs control such that the focal point describes a spiral, and performs control such that the central axis of the spiral moves along a curved surface.

This laser irradiation mechanism includes a control unit which has a function allowing the focal point of a laser beam to describe a circle, performs control such that the focal point describes a spiral, and performs control such that the central axis of the spiral moves along a curved surface.

An apparatus and method for making a three-dimensional object from a solidifiable material using two photon absorption is described. The use of two photon absorption allows for the creation of a non-solidification zone beneath the exposed surface of a solidifiable material so that no separation is required between the most recently solidified layer of the object and a substrate such as a glass, a film, or a glass/film combination. In addition, when used with a linear scanning device, two photon absorption causes solidification to occur within a small spot area, which provides a means for creating larger, higher resolution objects than DLP systems or laser systems that use single photon absorption.

A laser beam irradiation unit of a laser processing apparatus includes a pulse laser oscillator, a condenser which converges and irradiates a pulse laser beam upon a workpiece held on a chuck table, a dichroic mirror disposed between the pulse laser oscillator and the condenser, a strobo flash irradiation unit which irradiates light on a route of the dichroic mirror and the condenser, a beam splitter disposed between the strobo flash irradiation unit and the dichroic mirror, and an image pickup unit disposed on the route of the light split by the beam splitter. A control unit renders the strobo flash irradiation unit and the image pickup unit operative in a timed relationship with the pulse laser beam oscillated from the pulse laser beam oscillator and irradiated upon the workpiece and detects a processed state on the basis of an image signal from the image pickup unit.

A laser beam irradiation unit of a laser processing apparatus includes a pulse laser oscillator, a condenser which converges and irradiates a pulse laser beam upon a workpiece held on a chuck table, a dichroic mirror disposed between the pulse laser oscillator and the condenser, a strobo flash irradiation unit which irradiates light on a route of the dichroic mirror and the condenser, a beam splitter disposed between the strobo flash irradiation unit and the dichroic mirror, and an image pickup unit disposed on the route of the light split by the beam splitter. A control unit renders the strobo flash irradiation unit and the image pickup unit operative in a timed relationship with the pulse laser beam oscillated from the pulse laser beam oscillator and irradiated upon the workpiece and detects a processed state on the basis of an image signal from the image pickup unit.

A process head for processing a substrate using a laser beam, comprising: an optical unit including at least one optical element for directing the laser beam; a plurality of Bernoulli air bearings arranged to surround an optical axis of the optical element and configured to eject a first fluid flow for producing an attractive force between said Bernoulli air bearing and said substrate by the Bernoulli principle, so as to maintain a substantially constant spacing between said optical element and said substrate.

A method calibrates a laser processing machine by commanding a scan head to direct a laser beam to a desired position, then senses an actual position of the laser beam directly using a position sensitive detector (PSD) after the scan head is positioned. A relative position between the scan head and PSD is altered using one or more linear actuators. A position feedback loop is closed around the linear actuators so that the relative position of the laser beam on the PSD is reduced to zero. The actual position of the laser spot is then measured indirectly by encoders attached to linear axes of the laser processing machine. The actual position is stored in a memory. An error is determined as a difference between the desired position and the actual position. Compensation coefficients are determined from the error and stored for later use during operation of the laser processing machine.

The invention relates to a method and a laser machining device 10 for machining a workpiece 13. The laser machining device 10 has a laser 11 for generating a laser beam 12, which is deflected by way of a deflecting device 15 in accordance with a pattern defined by a control unit 14 and is directed onto a workpiece surface 17 of a workpiece 13, which surface is to be machined. The point of impingement 18 of the deflected laser beam 12b on the workpiece surface 17 is guided along at least one spiral path within a circular hatched area 16. The spiral path 19 is characterized by spiral path parameters. One spiral path parameter is the line spacing a between neighboring points of intersection P of the spiral path 19 with an axis running through the center point M of the spiral path 19.

According to a method for measuring the distance between a workpiece and a machining head of a laser machining apparatus, a machining head is provided, which has a housing that has an interior and an opening for emergence of the laser radiation from the machining head. The laser radiation is directed on to the workpiece, after it has passed through the interior and the opening. An object beam is directed on to the workpiece by a light source of an optical coherence tomograph in such a manner that the object beam passes through the interior and the opening before being incident upon the workpiece. In addition to the object beam, a measuring beam passes through the interior. The measuring beam is used to compensate falsifications of the measured distance that have been caused by pressure fluctuations in the interior. The measuring beam in this case may be reflected at a reflective face that is formed on an inner face of an outlet nozzle that comprises the opening, which inner face delimits the interior.

According to a method for measuring the distance between a workpiece and a machining head of a laser machining apparatus, a machining head is provided, which has a housing that has an interior and an opening for emergence of the laser radiation from the machining head. The laser radiation is directed on to the workpiece, after it has passed through the interior and the opening. An object beam is directed on to the workpiece by a light source of an optical coherence tomograph in such a manner that the object beam passes through the interior and the opening before being incident upon the workpiece. In addition to the object beam, a measuring beam passes through the interior. The measuring beam is used to compensate falsifications of the measured distance that have been caused by pressure fluctuations in the interior. The measuring beam in this case may be reflected at a reflective face that is formed on an inner face of an outlet nozzle that comprises the opening, which inner face delimits the interior.