A measuring device (10) for the interferometric shape measurement of a surface (12) of a test object (14-1; 14-2)includes (i) a diffractive optical element (26-1; 26-2) that generates a test wave (28) from incoming measurement radiation (18), wherein the diffractive optical element radiates the test wave onto the surface of the test object, (ii) a deflection element (22) that is disposed upstream of the diffractive optical element in the beam path of the measurement radiation, and (iii) a holding device (24, 124) that holds the deflection element and that changes a position of the deflection element (22) through a combination of a tilting movement and a translation movement.

An optical arrangement for a laser beam includes an f-theta lens. The f-theta lens is disposed in a divergent beam path of the optical arrangement in order to focus the laser beam into a focus plane. The focus plane is located at a distance from a focal plane of the f-theta lens.

An image forming apparatus includes a light emitting device that emits light, a movable mirror that reflects the light emitted from the light emitting device, a first actuator that causes the movable mirror to swing about a first axis, a first reference signal output portion that outputs a first reference signal by estimating a point in time when a deflection angle of the movable mirror about the first axis becomes equal to a first reference angle, a light emission controller that causes the light emitting device to emit the light based on the first reference signal output from the first reference signal output portion, an imaging apparatus that images the light reflected by the movable mirror, and a correction portion that corrects a timing of the first reference signal output by the first reference signal output portion based on imaging information acquired by the imaging apparatus.

A light source module includes a light source, a fluorescent ring, a reflector, and a driving device. The light source is configured to emit light. The fluorescent ring has an inner surface. The reflector is configured to reflect the light to form a light spot on the inner surface. The driving device is configured to rotate the reflector to cause the light spot to move along a circular path on the inner surface.

The embodiments described herein provide systems and methods that can improve performance in scanning laser devices. Specifically, the systems and methods utilize a non-uniform variation in optical expansion coupled with variation in the energy level of laser light pulses to provide an improved effective range over a scanning area. In general, the improved effective range varies over the scan field, with relatively long effective range in some areas of the scan field and relatively short effective range in other areas of the scan field. This varying range over the scan field is facilitated by expansion optics that provide a non-uniform variation in optical expansion for laser light pulses relative to position along a first axis in the scan field and by a light source controller that varies the energy level of the laser light pulses according to position along the first axis of the scan field.

An additive manufacturing apparatus includes a platform, a dispenser configured to deliver a plurality of successive layers of feed material onto the platform, at least one light source configured to generate a first light beam and a second light beam, a polygon mirror scanner, an actuator, and a galvo mirror scanner. The polygon mirror scanner is configured to receive the first light beam and reflect the first light beam towards the platform. Rotation of the first polygon mirror causes the light beam to move in a first direction along a path on a layer of feed material on the platform. The actuator is configured to cause the path to move along a second direction at a non-zero angle relative to the first direction. The galvo mirror scanner system is configured to receive the second light beam and reflect the second light beam toward the platform.

Systems and methods are described that relate to a scanning laser system configured to emit laser light and an interlock circuit communicatively coupled to the scanning laser system. The interlock circuit may carry out certain operations. The operations include, as the scanning laser system emits laser light into one or more regions of an environment around the scanning laser system, determining a respective predicted dosage amount for each region based on the emitted laser light. The operations further include detecting an interlock condition. The interlock condition includes a predicted dosage amount for at least one region being greater than a threshold dose. In response to detecting the interlock condition, the operations include controlling the scanning laser system to reduce a subsequent dosage amount in the at least one region.

A rotating steering mirror assembly comprising a first wedge rotatable relative to a base and a second wedge rotatable relative to the first wedge to controllably tilt a mirror on an outward- or forward-facing surface of the second wedge. Respective motors can independently rotate the first and second wedges.

A driving controller provides a first driving signal having a first driving frequency to a first actuator, provides a second driving signal having a second driving frequency to a second actuator, derives a first average phase delay time by averaging a first phase delay time of an output signal of a first angle detection sensor with respect to the first driving signal in a plurality of cycles, derives a second average phase delay time by averaging a second phase delay time of an output signal of a second angle detection sensor with respect to the second driving signal in a plurality of cycles, generates a first reference signal based on the first driving signal and the first average phase delay time, and generates a second reference signal based on the second driving signal and the second average phase delay time.

Systems and methods for determining the resonant frequencies of at least one axis of a two-axis resonant light scanner based on a measured resistance of at least a portion of one of the axes are disclosed. Precise knowledge of the resonant frequencies of each axis enables quasi-closed-loop operation of a light scanner, wherein the resonant frequencies of its axes can be periodically updated to ensure the proper drive frequencies are used. Furthermore, by determining the relationship between the measured resistance and scanner angle, calibration of the scanner is facilitated and even enabled at the wafer level during fabrication. In some cases, it also enables real-time monitoring of scanner position. Scanners in accordance with the present disclosure are suitable for use in any application that requires one or more reflective elements that can be scanned or steered in at least one dimension.