An optical scanning device causes a mirror portion to perform a spiral rotation operation with a first driving signal applied to a first actuator and a second driving signal applied to a second actuator as cyclic voltage signals. In a case where a resonance frequency and a resonance Q value of a resonance mode, among resonance modes accompanied by mirror tilt swing around a first axis, closest to a frequency of the cyclic voltage signal are respectively set as f.sub.r1 and Q.sub.1, a resonance frequency and a resonance Q value of a resonance mode, among resonance modes accompanied by mirror tilt swing around a second axis, closest to the frequency of the cyclic voltage signal are respectively set as f.sub.r2 and Q.sub.2, and the frequency of the cyclic voltage signal is f.sub.d, a relationship of Q.sub.1≠Q.sub.2, F.sub.r2<f.sub.r1, and f.sub.r2×(1−1/(1.2×Q.sub.2))≤f.sub.d≤f.sub.r1×(1+1/(6×Q.sub.1)) is satisfied.

A 3-dimensional shaping apparatus manufactures a 3-dimensional shaped object. The 3-dimensional shaping apparatus includes a beam irradiation unit, a spatial light modulator, a splitting optical system, and a scanning unit. The beam irradiation unit emits a light beam. The spatial light modulator spatially modulates the light beam emitted by the beam irradiation unit at least on the first axis. The splitting optical system includes at least one lens array having a plurality of lenses arranged along the first axis and splits the light beam modulated by the spatial light modulator into a plurality of light beams by the lens array. The scanning unit scans the shaping material with the plurality of light beams from the splitting optical system.

A multipass scanner usable e.g. in a near-eye display is disclosed. The multipass scanner scans a light beam angularly, forming an image in angular domain. The multipass scanner includes a light source, a tiltable reflector, and a multipass coupler that couples light emitted by the light source to the tiltable reflector, receives the reflected light and couples it back to the tiltable reflector to double the scanning angle. Then, the multipass coupler couples the light reflected at least twice from the tiltable reflector to an exit pupil of the scanner. A pupil-replicating waveguide disposed at the exit pupil of the scanner extends the image in angular domain. Multiple reflections of the light beam from the tiltable reflector enable one to increase the angular scanning range and associated field of view of the display without having to increase the angular scanning range of the tiltable reflector.

A microelectromechanical system MEMS structure is described. A first actuator is attached to a substrate and configured to rotate the substrate along a first axis of rotation. An array of rotatable MEMS mirrors is mounted on the substrate, aligned parallel to the first axis of rotation. Each rotatable MEMS mirror is rotatable about a second axis of rotation with each second axis of rotation being perpendicular to the first axis of rotation and parallel to every other axis of rotation. An array of second actuators is configured to rotate each of the rotatable MEMS mirrors about its corresponding second axis of rotation. A controller is configured to control the first actuator to rotate the substrate about the first axis of rotation. The controller further controls the array of second actuators to rotate each rotatable MEMS mirror of the array of rotatable MEMS mirrors about its corresponding second axis of rotation.

An excess heat-generating element is coupled to a heat sink through a heat conduction path. A thermal switch is mounted in the heat conduction path. A temperature-sensitive element is coupled to the heat conduction path on a same side of the thermal switch as the excess heat-generating element. A temperature monitor is mounted adjacent the temperature-sensitive element. A temperature controller has an input coupled to the temperature output of the temperature monitor and an output control line coupled to an input of the thermal switch. The temperature controller switches off the thermal switch, in response to detecting a temperature below a temperature threshold from the temperature output. When the thermal switch it off, it impedes heat flow from the excess heat-generating element to the heat sink, and the heat flow is redirected to increase heat flow from the excess heat-generating element to the heat-sensitive element.

To provide a display apparatus that makes it possible to further improve a performance in controlling video presentation according to characteristics of an eyeball of a user. A display apparatus is provided that includes a light source; a processor that performs processing on a distribution of characteristics of an eyeball; a monitoring section that monitors a state of the eyeball; a matching section that performs matching on the distribution of the characteristics of the eyeball and the state of the eyeball; and an irradiator that irradiates a specified position on a retina with video display light emitted by the light source.

An extreme ultra violet (EUV) light source apparatus includes a metal droplet generator, a collector mirror, an excitation laser inlet port for receiving an excitation laser, a first mirror configured to reflect the excitation laser that passes through a zone of excitation, and a second mirror configured to reflect the excitation laser reflected by the first mirror.

A mirror drive portion which causes a mirror portion to swing around a predetermined swing axis; a single optical sensor including a single light emission portion and a single light reception portion which receives light emitted from the light emission portion; a light blocking portion which is arranged in the mirror portion to swing together with the swing of the mirror portion and periodically blocks the light emitted from the light emission portion along with the swing; and a mirror control portion which controls the swing of the mirror portion based on an alternating voltage and a detection signal of the optical sensor, wherein the mirror control portion acquires a state of the swing of the mirror portion based on a light reception state of the light reception portion and a zero-cross timing of the alternating voltage, and controls the swing of the mirror portion.

This application discloses a galvanometer and a LiDAR. The galvanometer includes a first shaft and a second shaft. A first shaft drive voltage is used to control the galvanometer to vibrate around the first shaft, a second shaft drive voltage is used to control the galvanometer to vibrate around the second shaft, and the first shaft drive voltage and the second shaft drive voltage are superimposed to drive the galvanometer. There are N working intervals in a second shaft drive period, and in the N working intervals, the second shaft drive voltage and the first shaft drive voltage jointly drive the galvanometer to form N scanning tracks. The N scanning tracks do not coincide and N is a positive integer.

An optical combiner includes a curved reflective element and a rotating mirror configured to rotate through a range of angular displacement. During a first time period, the curved reflective element is configured to reflect a first light beam emitted from a first light source to the rotating mirror when the rotating mirror is disposed at a first angular displacement, and the rotating mirror is configured to receive the first reflected light beam and provide a first output light beam along an output optical axis. During a second time period, the curved reflective element is configured to reflect a second light beam emitted from a second light source to the rotating mirror when the rotating mirror is disposed at a second angular displacement, and the rotating mirror is configured to receive the second reflected light beam and provide a second output light beam along the output optical axis.