Abstract: A compact single-axis confocal endomicroscope is provided, capable of complying with 2.8 mm diameter endoscope space requirements. The single-axis confocal endomicroscope uses a folded path design achieved between a fixed mirror and a lateral plane scanning mirror thereby producing high numerical apertures that allow for diffraction-limited resolution in sub-surface scanning. The scanning mirror has a central aperture that allows for illumination beam expansion in the folded path design.

Abstract: An oscillator control system includes an oscillator structure configured to oscillate about first and second rotation axes according to a Lissajous pattern, wherein an oscillation about the second rotation axis imparts a cross-coupling error onto an oscillation about the first rotation axis, and wherein the cross-coupling error changes in accordance with a Lissajous position within the Lissajous pattern; and a driver circuit that includes a phase-locked loop (PLL) configured to regulate a driving signal that drives the oscillation about the first rotation axis. The PLL is configured to generate a PLL signal based on a phase error of the oscillation about the first rotation axis. The PLL includes a compensation circuit configured to receive the PLL signal and the Lissajous position within the Lissajous pattern, apply a compensation value to the PLL signal to generate a compensated PLL signal used for generating the driving signal based on the Lissajous position.

Abstract: An optical module includes a light-forming unit configured to form light, and a protective member surrounding and sealing the light-forming unit. The light-forming unit includes a laser diode, a first MEMS including a first mirror having a first reflective surface that reflects and scans light from the laser diode, the first mirror oscillating to form a first plane, and a second MEMS including a second mirror having a second reflective surface that reflects and scans light from the first mirror, the second mirror oscillating to form a second plane orthogonal to the first plane.

Abstract: A micromechanical component. The micromechanical component includes: a mount; a displaceable part; and a first serpentine spring and a second serpentine spring which is embodied mirror-symmetrically with respect to the first serpentine spring in terms of a first plane of symmetry; a first actuator device and a second actuator device being embodied in such a way that by way of the first actuator device and the second actuator device, periodic deformations, mirror-symmetrical in terms of the first plane of symmetry, of the first serpentine spring and of the second serpentine spring are excitable; the micromechanical component also encompassing a first torsion spring and a second torsion spring that each extend along a rotation axis; and the displaceable part being displaceable, at least by way of the periodic and mirror-symmetrical deformations of the first serpentine spring and of the second serpentine spring, around the rotation axis with respect to the mount.

Abstract: An apparatus includes a scan module having one or more laser sources that generate one or more initial laser beams and two or more beam deflectors that deflect the initial laser beam(s). A beam optic substantially collimates the initial laser beam(s) to produce one or more collimated laser beams. One or more beam deflector controllers control the angle of beam deflection from each beam deflector. Relay optics between the two or more beam deflectors image each sequential beam deflector onto the subsequent beam deflector in such a manner that the beam deflecting from the last beam deflector in an optical chain contains a combination or superposition of all the beam deflections of the beam deflectors in the sequence, and maintains a beam divergence of the one or more collimated beams.

Abstract: 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.

Abstract: Controlling a mirror in a MEMS based projector. A method includes iteratively performing various acts. The method includes inputting a time domain target wave array, with target elements, to a system for a MEMS coupled to the mirror of the projector. The time domain target wave array includes a set of n target elements. The method further includes driving the driver to move the mirror using elements in a drive array comprising a set of drive elements. The method further includes sampling a time domain output wave for the movement of the mirror to construct an output wave array with output elements corresponding to the target elements. The method further includes identifying errors between the target elements and the output elements. The method further includes modifying the drive elements in the drive array to attempt to minimize the errors when driving the MEMS on subsequent drive cycles.

Abstract: A printer includes a head, a lamp, a first sensor, and a processor. The head is configured to eject photocurable ink onto the object to be printed supported by a platen. The lamp is configured to irradiate light onto the object to be printed on which the ink is ejected. The first sensor is provided inside the printer, and is configured to detect a temperature inside the printer. The processor causes the first sensor to acquire the temperature inside the printer. The processor acquires, based on the print data, a duty ratio indicating a printing ratio when ejecting the ink onto an ejection region of the object to be printed. The processor sets an illuminance of the light irradiated by the lamp, based on the temperature acquired by the first sensor and the acquired duty ratio.

Abstract: A microelectromechanical device includes a fixed structure defining a cavity with a tiltable structure that is elastically suspended in the cavity. A piezoelectrically driven actuation structure, interposed between the tiltable structure and the fixed structure, is biased for causing rotation of the tiltable structure about a first rotation axis belonging to a horizontal plane in which the tiltable structure rests. The actuation structure includes a pair of driving arms carry respective regions of piezoelectric material and are elastically coupled to the tiltable structure on opposite sides of the first rotation axis through respective elastic decoupling elements. The elastic decoupling elements exhibit stiffness in regard to movements out of the horizontal plane and compliance to torsion about the first rotation axis.

Abstract: A mirror device includes a frame body, a shaft member provided inside the frame body and connected to the frame body at both end portions, and a reflection member fixed to the shaft member and provided so as to be capable of swinging around an axis of the shaft member. The reflection member has a base portion provided along an axial direction of the shaft member and a reflection portion provided on the base portion. The base portion has a three-dimensional uneven structure including a bottom wall portion having a main surface provided along the axial direction of the shaft member and a plurality of side wall portions extending from the bottom wall portion on the side opposite to the reflection portion.

Abstract: Methods and systems for using a dual sided MEMS mirror for determining a direction of a LiDAR beam are disclosed. In one example a MEMS package includes a dual sided MEMS mirror that is manipulable about two orthogonal axes. A first surface of the MEMS mirror is used to steer a LiDAR beam that is used to perform LiDAR imaging of an area of interest. As the mirror is moved, a second surface of the mirror reflects a sensing beam onto a position sensitive device. Data from the position sensitive device is used to determine a position of the mirror which can be used to determine a direction of the steered LiDAR beam.

Abstract: An oscillator system includes an electrostatic oscillator structure configured to oscillate about an axis based on a deflection that varies over time; an actuator configured to drive the electrostatic oscillator structure about the axis, the actuator including a first capacitive element having a first capacitance dependent on the deflection and a second capacitive element having a second capacitance dependent on the deflection; a sensing circuit configured to receive a first displacement current from the first capacitive element and a second displacement current from the second capacitive element, to integrate the first displacement current to generate a first capacitive charge value, and to integrate the second displacement current to generate a second capacitive charge value; and a measurement circuit configured to receive the first and the second capacitive charge values and to measure the deflection of the electrostatic oscillator structure based on the first and the second capacitive charge values.

Abstract: A light scanning apparatus includes a light source configured to intermittently emit light based on an irradiation timing signal; a mirror configured to reflect the light emitted by the light source; an actuator configured to cause the mirror to be deflected based on drive signals; a sensor configured to output a signal according to deflection of the mirror; an irradiation timing adjusting-unit configured to adjust the irradiation timing signal based on the output signal of the sensor; and an irradiation timing storage configured to store the adjusted irradiation timing signal.

Abstract: A MEMS scanning device (“Device”) includes at least (1) laser projector(s) controlled by a laser drive to project a laser beam, (2) MEMS scanning mirror(s) controlled by a MEMS drive to scan the laser beam to generate a raster scan, (3) a display configured to receive the raster scan, (4) a thermometer configured to detect a current temperature, (5) a display observing camera configured to capture an image of a predetermined area of the display, and (6) a computer-readable media that stores temperature model(s), each of which is custom-built using machine learning. The device uses the display observing camera to capture image(s) of predetermined pattern(s), which are then used to extract feature(s). The extracted feature(s) are compared with ideal feature(s) to identify a discrepancy. When the identified discrepancy is greater than a threshold, the temperature model(s) are updated accordingly.

Abstract: The techniques disclosed herein provide methods, devices, and systems to compensate the drive waveform to a slow-scan mirror in a laser beam scanning (LBS) display device. The slow-scan controller generates the drive waveform, which is combined with feedback and coupled to the input of a notch filter in the control loop. Ripple in the slow-scan mirror trajectory, which occurs as a consequence of mismatches between the notch frequency of the notch filter and the resonance of the slow-scan mirror, is effectively suppressed in real time by an adaptive notch compensator. Consequently, the described compensation scheme allows for relaxed notch filter design criteria with high tolerance and mitigation of ripple is achieved at reduced cost. The parameters, logic and blocks of the adaptive notch compensator scheme may be time-domain or frequency domain solutions that are implemented, in hardware, software or combinations thereof.

Abstract: An opto-electro-mechanical system for manipulating optical radiation comprising a rotationally or translationally movable element, wherein the element is itself an optical element or comprises an optical element. Furthermore the system comprises a stator for the movable element having a recess enabling a deflection range, a flexible connection between the stator and the movable element providing a corresponding kinematically defined mobility, and an actuator for deflecting the movable element, wherein the stator is connected as one piece to the movable element, and the one-piece connection consists of silicate glass- and the recess is arranged around the movable element in such a way that the movable element is deflectable in accordance with the kinematically defined mobility with elastic deformation of the connection by means of the actuator.

Abstract: 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.

Abstract: An input device includes an optical sensor which senses an object on a plane where the emitted light travels, an optical member which changes a path of the light emitted from the optical sensor, and a processing unit which performs input processing based on sensing results of the optical sensor; the optical sensor and the optical member form a first sensing surface consisting of a planar region in which the light emitted from the optical sensor travels and a second sensing surface that is farther from the optical sensor than the first sensing surface, and the processing unit performs the input processing based on a first sensing result of the optical sensor on the first sensing surface and a second sensing result of the optical sensor on the second sensing surface.

Abstract: A system that uses a scalable array of individually controllable laser beams that are generated by a fiber array system to process materials into an object. The adaptive control of individual beams may include beam power, focal spot width, centroid position, scanning orientation, amplitude and frequency, piston phase and polarization states of individual beams. Laser beam arrays may be arranged in a two dimensional cluster and configured to provide a pre-defined spatiotemporal laser power density distribution, or may be arranged linearly and configured to provide oscillating focal spots along a wide processing line. These systems may also have a set of material sensors that gather information on a material and environment immediately before, during, and immediately after processing, or a set of thermal management modules that pre-heat and post-heat material to control thermal gradient, or both.

Abstract: The present disclosure provides a laser projection device and a laser projection system. The laser projection device includes a light source scanner and a MEMS scanning mirror, the light source scanner including micro laser diodes; and the micro laser diodes are used to provide laser beams needed for image projection, and the laser beams are projected to the MEMS scanning mirror, and then reflected by the MEMS scanning mirror to a predetermined area to form a projection image. By providing the micro laser diodes in the laser projection device and initiatively emitting laser by exciting the micro laser diodes, the present disclosure does not need an external laser source and facilitates the reduction of the size of the laser projection device, as compared with the prior art.

Abstract: An optical fiber scanning system includes: an optical fiber with a magnet; four drive coils configured to apply a drive magnetic field generated using a drive power signal to the magnet; four detection coils configured to output a detection signal in response to variation of a magnetic field; a controller configured to perform feedback control of the drive power signal; a signal output circuit configured to output a drive signal; a voltage-current conversion circuit configured to convert the drive signal to the drive power signal; and a correction circuit configured to output a magnet magnetic field signal by removing the drive magnetic field signal from the detection signal, and the controller controls the signal output circuit based on the magnet magnetic field signal.

Abstract: An ear inspection device configured for being at least partially introduced into an external ear canal for determining an ear condition, such as temperature, in particular at the subject's eardrum, wherein the device comprises an infrared sensor unit configured for detecting infrared radiation from the ear, and an electronic imaging unit configured for capturing images based on radiation in the visible range from the ear, wherein the electronic imaging unit exhibits at least one optical axis arranged such that it can be radially offset within the ear canal, and wherein the infrared sensor unit exhibits a visual axis arranged such that it can be positioned centrically within the ear canal or radially offset within the same semicircle, especially the same quadrant, of the cross section of the ear canal.

Abstract: Controlling a mirror in a MEMS based projector. A method includes iteratively performing various acts. The method includes inputting a time domain target wave array, with target elements, to a system for a MEMS coupled to the mirror of the projector. The time domain target wave array includes a set of n target elements. The method further includes driving the driver to move the mirror using elements in a drive array comprising a set of drive elements. The method further includes sampling a time domain output wave for the movement of the mirror to construct an output wave array with output elements corresponding to the target elements. The method further includes identifying errors between the target elements and the output elements. The method further includes modifying the drive elements in the drive array to attempt to minimize the errors when driving the MEMS on subsequent drive cycles.

Abstract: Embodiments of optical scanners, optical projection systems, and methods of scanning optical waveguides and projecting images are described. The disclosed devices, systems and methods advantageously provide an improvement to the compactness, robustness, simplicity, and reliability of optical scanners and optical projection systems by implementing a thermally driven actuator for inducing oscillations of a cantilever within the optical scanners and optical projection systems. The stability and accuracy of optical scanners and optical projection systems are further enhanced using capacitive sensing, feedback, and phase correction techniques described herein.

Abstract: Examples are disclosed that relate to actuator frames for scanning mirror systems. In one example an actuator frame for a scanning mirror assembly comprises a mounting member comprising a first side and an opposite second side. A first moveable member comprises a first interior side that defines a first gap and a second gap with the first side of the mounting member. A second moveable member comprises a second interior side that defines a third gap and a fourth gap with the second side of the mounting member. A first hinge connects a central portion of the mounting member with the first moveable member, and a second hinge connects the central portion of the mounting member with the second moveable member.

Abstract: A substrate having a plurality of features for use in measuring a parameter of a device manufacturing process and associated methods and apparatus. The measurement is by illumination of the features with measurement radiation from an optical apparatus and detecting a signal arising from interaction between the measurement radiation and the features. The plurality of features include first features distributed in a periodic fashion at a first pitch, and second features distributed in a periodic fashion at a second pitch, wherein the first pitch and second pitch are such that a combined pitch of the first and second features is constant irrespective of the presence of pitch walk in the plurality of features.

Abstract: An actuator device and a method for tilting an actuator device. The method includes the steps: conducting electrical current through an electrical conduction device, which is guided via a tilting device of the actuator device, within a first magnetic field that is generated by a permanent magnet device of the actuator device, so that an actuator element of the tilting device is tilted along a first tilting axis as the result of a Lorentz force; and generating a second magnetic field by an electromagnet device of the actuator device in the area of the permanent magnet device, so that the tilting device is tilted along a second tilting axis as the result of magnetic attraction and repulsion.

Abstract: The present invention is to provide an optical scanner module capable of reducing cross-talk generated between a sensor interconnect and a drive interconnect.

Abstract: A piezo MEMS mirror system that includes a drive system that drives a piezo MEMS mirror that generates an image on a portable device display. The drive system includes a DC-AC converter that operates to convert the DC power provided by the battery to AC power. The DC-AC converter may generate the AC power having a peak voltage that is at an intermediate level—being between the DC voltage of the battery, and the peak AC voltage generated by the drive system. The drive system also includes an output filter that uses a series-coupled inductance system (perhaps inductively coupled inductors in a differential mode circuit) in conjunction with a capacitance of the piezo MEMS mirror (and perhaps tuning capacitors to account for mirror fabrication deviations) to amplify the AC voltage of the AC power at a mechanical resonant frequency of the piezo MEMS mirror.

Abstract: The wiring board includes an insulating substrate having a main surface, an external electrode on the main surface and an outer edge portion of the insulating substrate, and a dissipating metal layer on the main surface of the insulating substrate, the dissipating metal layer having a greater area than the external electrode if viewed in a plan, the dissipating metal layer being adjacent to the external electrode and having a slit. The slit has an opening at an outer periphery of the dissipating metal layer. The external electrode faces the opening.

Abstract: A scanning mirror resonates on a first axis and moves on a second axis at a frequency dictated by a sync signal. The period of movement on the second axis is not necessarily an integer multiple of the period of movement on the first axis. A drive circuit excites movement of the mirror. The drive circuit adds a position offset to the signal that excites movement on the second axis. The position offset is capable of causing the resonant movement on the first axis to scan a substantially identical trajectory for at least a portion of each period on the second axis.

Abstract: An apparatus has a detection unit, a rotating polygonal mirror and a generation unit. The rotating polygonal mirror has reflecting surfaces and configured to deflect light. The detection unit outputs a first signal in accordance with detecting the light. The generation unit, based on the first signal, generates a second signal which is a main scanning synchronization signal for controlling a write start in a main scanning direction. The second signal has a first waveform and a second waveform. The first waveform does not correspond to a reference reflection surface. The second waveform corresponds to the reference reflection surface and is different to the first waveform.

Abstract: A micromechanical component includes a mount; a drive body on which at least one coil device is disposed and which is connected to the mount by way of at least one spring such that the drive body can be set into a driving motion by an interaction of a current conducted through the at least one coil device and a magnetic field present at the at least one coil device; and a control element connected to the drive body such a manner that a setting of the drive body into a driving motion causes the control element to be set into a deflection motion with at least one motion component directed about a rotation axis. At least one connecting element disposes the drive body and control element relative to each other such that the rotation axis extends at a spacing from a center of gravity of the drive body.

Abstract: An optical deflector includes a mirror rotatable around a rotating shaft of the optical deflector, the mirror including a base made of metal and a reflective surface, the reflective surface being parallel to an axial direction of the rotating shaft of the mirror. The mirror has a length that is twice a length from a center of the rotating shaft to the reflective surface, which is shorter than a length of the reflective surface in the direction of the rotating shaft.

Abstract: The underlying invention presents a device which connects a vibratably suspended optical element to at least two actuators mounted fixedly on one side via curved spring elements, wherein the actuators are implemented to cause the vibratably suspended optical element to vibrate via the curved spring elements. Both the actuators and the entire system may be implemented to be more robust and be operated more reliably due to the curved shaping of the spring elements.

Abstract: A micromechanical mirror includes a mobile mass carrying a mirror element and provided in a body including semiconductor material. A driving structure is coupled to the mobile mass to cause a scanning movement thereof. The driving structure is configured to generate a combination of a two or more sinusoidal resonant modes in the micromechanical mirror at respective resonant frequencies. This combination approximates a scanning pattern of the mobile mass defined by a linear function which may, in particular, be a triangular shaped function.

Abstract: An optical scanning device includes an optical fiber, a holding member cantilevering the optical fiber, a first driving device placed on the distal end of the optical fiber and making the optical fiber vibrate in a first direction, and a second driving device placed between the holding member for the optical fiber and the first driving device and making the optical fiber vibrate in a second direction which crosses the first direction.

Abstract: A resonance locking system for a pico-projector, the system comprising a resonance frequency sensor operative for sensing change in resonance frequency of a miniature mechanical device (10) including a moving mirror assembly having a driving frequency, by comparing a current resonance frequency to a reference; and a feedback loop changing at least one aspect of use of the miniature moving mirror assembly responsive to a current value of the resonance frequency measured by the sensor.

Abstract: An optical deflector includes a mirror, an inner frame surrounding the mirror, first and second torsion bars coupled between the mirror and the inner frame, first and second inner piezoelectric actuators coupled between the first and second torsion bars supported by first and second inner coupling portions to the inner frame, and an outer frame surrounding the inner frame. The inner frame is supported by first and second outer coupling portions to the outer frame. A circumferential rib is provided on a rear surface of the inner frame. A first branch rib is provided on a rear surface of the first outer coupling portion, and a second branch rib is provided on a rear surface of the second outer coupling portion.

Abstract: A metal elastic member to be used for beams 4 for supporting a movable unit 3 at respective ends with respect to a fixed unit 2 in a miniature machine including at least one movable unit 3, the fixed unit 2 and the beams 4 , and capable of swinging the movable unit about an axis P with the beams 4 serving as torsional rotation axes, includes a metal bar 4a having a predetermined length, a fixed unit pad 4b that is provided at a first end of the metal bar 4a and is fixed to the fixed unit 2, and a movable unit pad 4c formed on the other end side of the metal bar 4a and fixed to the movable unit 3. At least the metal bar 4a is molded to have a sectional area of 1 mm2 or less by using a physical or chemical processing method excluding a mechanical processing method and swings the movable unit 3 within a frequency of 150 Hz to 500 Hz.

Abstract: Disclosed are a method and an apparatus for selecting a wavelength by a wavelength tunable optical receiver. The method of selecting a wavelength of a wavelength tunable optical receiver includes: receiving, by the wavelength tunable optical receiver, an optical signal from a wavelength tunable optical transmitter; filtering, by the wavelength tunable optical receiver, the optical signal through a low frequency band electrical signal filter, and obtaining a low frequency signal; determining, by the wavelength tunable optical receiver, whether the low frequency signal is a valid signal based on a current value of the low frequency signal; and when the low frequency signal is the valid signal, obtaining, by the wavelength tunable optical receiver, an enable condition of a wavelength tunable optical filter through which the low frequency signal is selected, in which the low frequency signal includes a control/monitoring signal.

Abstract: A flexible scan element for a laser scanner is disclosed. The flexible can element may be made from a non-linear elastomeric material that twists sufficiently for scan operation but resists unwanted motion from shock/vibration through the use of a rigid motion-limiting member encapsulated, at least partially, within the body of the flexible scan element. In this way, no external components are required for limiting excess motion.

Abstract: An optical scanner includes: a base portion; a light reflecting portion that reflects light; a connection portion that connects the base portion and the light reflecting portion; and a shaft portion that supports the base portion in a swingable manner, wherein the light reflecting portion is disposed so that a geometrical center of the light reflecting portion is separated from a geometrical center of the base portion in a plan view, and wherein the light reflecting portion includes a center of gravity adjusting portion that performs adjustment so that a distance between the geometrical center of the base portion and a center of gravity of the light reflecting portion in the plan view becomes smaller than a distance between the geometrical center of the light reflecting portion and the geometrical center of the base portion in the plan view.

Abstract: An apparatus (10) for deflecting and for widening a visible range of a camera (24) is provided, wherein the apparatus (10) has a first mirror element (12) which is tilted with respect to the optical axis of the camera (24) in a longitudinal direction in order to supply light to the camera (24) from a visible range lying laterally with respect to the optical axis. In this connection the first mirror element (12) is additionally tilted in a transverse direction perpendicular to the longitudinal direction and the apparatus has a second mirror element (14) besides the first mirror element (12) which is tilted in the longitudinal direction and in the transverse direction with respect to the first mirror element (12).

Abstract: There are provided a video projection device and a video projection method which can realize both a guarantee of safety and an increase in luminance of a screen. The video projection device includes: a laser light source unit which emits a laser; a laser scanning unit which is provided with one or more scanning directions and project video by performing a reciprocating scan of the laser with respect to a scanning direction with the highest scanning frequency; and a control unit which controls operations of the laser light source unit and the laser scanning unit depending on a video signal so that a scanning angle when emission of the laser in an outgoing path is stopped is different from a scanning angle when emission of the laser in a return path is started with respect to the scanning direction along which the reciprocating scan is performed.

Abstract: A method and apparatus for resonant rotational oscillator have been disclosed. In one version a moving coil is mounted on a rotating member. By using a magnetic assembly and the moving coil the rotating member is made to rotate.

Abstract: An optical switch includes: a semiconductor substrate, including a first rotation part and a first torsion beam disposed at two ends of the first rotation part, where the first torsion beam is configured to drive the first rotation part to rotate; a microreflector, disposed on a surface of the first rotation part of the semiconductor substrate; a first latching structure, disposed on a surface of the first torsion beam, the first latching structure including a form self remolding (FSR) material layer and a thermal field source, where the thermal field source is configured to provide a thermal field for the FSR material layer and the FSR material layer is configured to undergo form remolding under the thermal field, so as to latch the first rotation part and the microreflector in a position after rotation.

Abstract: An optical reflecting device includes a fixed frame, a pair of first oscillation parts, a movable frame, a pair of second oscillation parts, and a mirror part. One-side ends of the first oscillation parts are connected to the inside of the fixed frame. The movable frame is connected to and held by the other-side ends of the pair of first oscillation parts to be pivotable. One-side ends of the pair of second oscillation parts are connected to the inside of the movable frame and the pair of second oscillation parts are disposed to be substantially perpendicular to the pair of first oscillation parts. The mirror part is connected to and held by the other-side ends of the pair of second oscillation parts to be pivotable. The first oscillation parts have a meandering shape in which a plurality of straight portions and a plurality of folded portions are formed, and a stepped structure portion is provided in part of the folded portion.

Abstract: A projection controlling method for controlling a MEMS scanning mirror to repeatedly scan an image light on a surface and form a projection image is provided. A resonance frequency of the MEMS scanning mirror which swings around a first swing axis is detected and provided to a filter unit as a parameter of a filtering process. A first periodic control signal with a first frequency and a plurality of harmonic components is generated. The harmonic component with the resonance frequency is filtered from the first periodic control signal by the filter unit. The filtered first periodic control signal is provided to the MEMS scanning mirror to control the MEMS scanning mirror to swing around the first swing axis according to the first frequency and to scan the image light on the surface back and forth along a first direction. A MEMS projection apparatus is also provided.

Abstract: An optical scanning device includes a mirror part including a mirror reflecting surface to reflect incident light, a pair of torsion bars configured to support the mirror part from both sides and configured to form a first axis around which to swing the mirror part by a torsional motion thereof so as to deflect the reflected light, and at least one stress alleviation area configured to alleviate a stress generated by the torsional motion of the torsion bars. The alleviation area is provided between an intersection of a second axis perpendicular to the first axis and passing through the center of the mirror reflecting surface and an edge of the mirror reflecting surface, and at least one of the torsion bars.