A mirror unit 2 includes a mirror device 20 including a base 21 and a movable mirror 22, an optical function member 13, and a fixed mirror 16 that is disposed on a side opposite to the mirror device 20 with respect to the optical function member 13. The optical function member 13 is provided with a light transmitting portion 14 that constitutes a part of an optical path between the beam splitter unit 3 and the fixed mirror 16. The light transmitting portion 14 is a portion that corrects an optical path difference that occurs between an optical path between the beam splitter unit 3 and the movable mirror 22 and the optical path between the beam splitter unit 3 and the fixed mirror 16. The second surface 21b of the base 21 and the third surface 13a of the optical function member 13 are joined to each other.

Embodiments of the disclosure provide a micromachined mirror assembly for controlling optical directions in an optical sensing system. The micromachined mirror assembly may include a micro mirror configured to direct an optical signal into a plurality of directions. The micromachined mirror assembly may also include at least one actuator coupled to the micro mirror and configured to drive the micro mirror to tilt around an axis. The micromachined mirror assembly may further include one or more objects attached to the micro mirror. The one or more objects may be asymmetrically disposed with respect to the axis to create an imbalanced state of the micro mirror when the micro mirror is not driven by the at least one actuator.

A MEMS actuator includes: a drive circuit for applying a drive voltage having a time waveform, which periodically repeats rising and falling and includes a period to be a constant voltage after the rising and before the falling, between a fixed comb electrode and a movable comb electrode; and a timing detection circuit that generates a capacitance derivative signal indicating a derivative value of a capacitance between the fixed comb electrode and the movable comb electrode by converting a current signal, which is output from the fixed comb electrode or the movable comb electrode within the period due to a change in the capacitance, into a voltage signal and detects a timing when the capacitance derivative signal reaches a threshold value. The drive circuit controls a relationship between the timing detected by the timing detection circuit and a timing of the falling to be constant.

An optical device includes a support portion a movable unit and a pair of torsion bars disposed on both sides of the movable unit on a first axis. The movable unit includes a main body portion, a ring-shaped portion surrounding the main body portion when viewed from a predetermined direction perpendicular to the first axis, two connection portions connecting the main body portion and the ring-shaped portion to each other, and a rib portion provided to the main body portion. Each of the two connection portions includes two connection regions that are separated from each other by a space and the each of the two connection region connects the main body portion and the ring-shaped portion to each other. The rib portion includes four extending portions radially extending between a center of the main body portion and the four connection regions respectively when viewed from the predetermined direction.

A microelectromechanical device having a first substrate of semiconductor material and a second substrate of semiconductor material having a bonding recess delimited by projecting portions, monolithic therewith. The bonding recess forms a closed cavity with the first substrate. A bonding structure is arranged within the closed cavity and is bonded to the first and second substrates. A microelectromechanical structure is formed in a substrate chosen between the first and second substrates. The device is manufactured by forming the bonding recess in a first wafer; depositing a bonding mass in the bonding recess, the bonding mass having a greater depth than the bonding recess; and bonding the two wafers.

Disclosed herein is a circuit for determining failure of a movable MEMS mirror. The circuit includes an integrator receiving an opening angle signal representing an opening angle of the movable MEMS mirror, and a differentiator receiving the opening angle signal. A summing circuit is configured to sum the integrator output and the differentiator output. A comparison circuit is configured to determine whether the sum of the integrator output and differentiator output is not within a threshold window. An indicator circuit is configured to generate an indicator signal indicating that the movable MEMS mirror has failed based on the comparison circuit indicating that the sum of the integrator output and differentiator output is not within the threshold window.

A MEMS device is obtained by forming a temporary biasing structure on a semiconductor body, and forming an actuation coil on the semiconductor body, the actuation coil having at least one first end turn, one second end turn and an intermediate turn arranged between the first and the second end turns and electrically coupled to the first end turn through the temporary biasing structure. In this way, the intermediate turn is biased at approximately the same potential as the first end turn during galvanic growth, and, at the end of growth, the actuation coil has an approximately uniform thickness. At the end of galvanic growth, portions of the temporary biasing structure are selectively removed to electrically separate the first end turn from the intermediate turn and from a dummy biasing region adjacent to the first end turn.

The present application discloses a deflector including a substrate portion, a movable portion, a reflective portion, a support portion, and a moving mechanism. The movable portion is supported by a first end of the support portion. A second end of the support portion is supported by the substrate portion. An end of the movable portion is capable of coming into contact with the substrate portion. The reflective portion is formed on the movable portion. The moving mechanism is capable of driving the movable portion so as to bring the movable portion into at least any one of a first state, a second state, a third state, and a fourth state.

A micromirror device includes a first support portion that is connected to the mirror portion on a first axis located in a plane including the reflecting surface of the mirror portion in a stationary state, and that swingably supports the mirror portion around the first axis. The first support portion is composed of a main shaft stretched along the first axis and a plurality of sub-shafts symmetrically disposed on both sides of the main shaft across the first axis and stretched along the first axis, the first support portion has a folded structure having three or more folded portions formed by connecting the plurality of sub-shafts, and in a case where inner curvature radii of the folded portions are denoted by R.sub.1, R.sub.2, R.sub.3, ... , in order from the closest to the first axis, a relationship of 0.73 ≤ R.sub.k+1/R.sub.k ≤ 0.9 (k = 1, 2, ...) is satisfied.

A method for making a micro-electro mechanical (MEMS) device includes forming a MEMS mirror stack on a handle layer, and applying a first bonding layer to the MEMS mirror stack. The method continues with disposing a substrate on the first bonding layer such that the MEMS mirror stack is mechanically anchored to the substrate and so as to seal against ingress of environmental contaminants, removing the handle layer, and applying a second bonding layer to the MEMS mirror stack. A cap layer is disposed on the second bonding layer such that the cap layer is mechanically anchored to the MEMS mirror stack and so as to seal against ingress of environmental contaminants.