A light-recycling light system (LRLS) that, in some embodiments, uses a transparent solid body (also called a lens) with some surfaces having total-internal-reflection (TIR) characteristics, optionally having no reflective coatings, making the system easy to make and low cost. In some embodiments, the lens includes an input face, an output face, and a curved (elliptical or parabolic) side surface that exhibits TIR, wherein the curved side surface defines a first focus at the input face and a second focus at the output face, so recirculating light entering at the first focus and reflecting at one side of the curved surface by TIR toward the second focus, hen reflects at the second focus toward the opposite side of the curved surface, and then reflects at the second side of the curved side surface by TIR toward the first focus. A light source emits light at the first focus.

An electrowetting system is disclosed. The system includes electrodes configured to manipulate droplets of fluid in a microfluidic space. Each electrode is coupled to circuitry operative to selectively apply a driving voltage to the electrode. The system includes a dielectric stack including a first dielectric pair comprising a first layer having a first dielectric constant and a second layer having a second dielectric constant. The second dielectric constant is larger than the first dielectric constant. The dielectric stack includes a second dielectric pair comprising a third layer having a third dielectric constant and a fourth layer having a fourth dielectric constant. The fourth dielectric constant is larger than the third dielectric constant. A ratio of a thickness of the fourth layer to a thickness of the third layer (T.sub.4:T.sub.3) is in the range from about 2:1 to about 8:1. The second dielectric pair is thinner than the first dielectric pair.

A color gamut conversion module, a conversion method thereof, and a projection device are provided. The color gamut conversion module includes a wavelength conversion element and a light filtering element. The wavelength conversion element includes at least two wavelength conversion regions, and the light filtering element includes at least one filtering region. Each filtering region is a single-band light filtering region or a multi-band light filtering region. In a visible light transmittance spectrum, the single-band light filtering region includes a band-pass wave band, and the multi-band light filtering region includes a plurality of first band-pass wave bands and a plurality of first cut-off wave bands. In a first color gamut mode, the wavelength conversion element and the light filtering element rotate at a first relative rate. In a second color gamut mode, the wavelength conversion element and the light filtering element rotate at a second relative rate.

A rotation wheel, comprising a substrate, a driving assembly, a clamping member and a balancing assembly. The driving assembly is connected with the substrate, and is configured to drive the substrate to rotate around an axis of the driving assembly as the central axis. The clamping member is disposed along the axis on the substrate. The balancing assembly includes at least one balancing material, an adhesive material and at least one channel. The adhesive material encapsulates the balancing material and is filled into the channel to fix the balancing assembly onto the clamping member. The rotation wheel and the projection apparatus of the invention exhibit favorable structural reliability.

A wavelength conversion element configured to receive an excitation light beam includes: a substrate configured to rotate about a central axis including a wavelength conversion region and a non-wavelength conversion region; and at least one wavelength conversion layer. When the substrate is rotated about the central axis, the non-wavelength conversion region and the wavelength conversion region alternately enter a transmission path of the excitation light beam. The substrate has a recessed portion located inside or outside of and surrounding the wavelength conversion region. The recessed portion includes an inclined surface. When the excitation light beam is incident on the inclined surface, the inclined surface reflects the excitation light beam to the wavelength conversion layer, and the wavelength conversion layer converts the excitation light beam into a converted beam. When the excitation light beam is incident on the non-wavelength conversion region, the non-wavelength conversion region reflects the excitation light beam.

Control systems for liquid lenses can use feedback control using one or more measured parameters indicative of a position of the fluid interface in the liquid lens. Capacitance between a fluid and an electrode in the liquid lens can vary depending on the position of the fluid interface. Current mirrors can be used for making measurements indicative of the capacitance and/or the fluid interface position. The liquid lens can be calibrated using the measurements indicative of capacitance and/or fluid interface position as the voltage is driven across an operational range. A control system can use pulse width modulation (PWM) for driving a liquid lens, and a carrier frequency for the PWM signals can be varied to control power consumption in the liquid lens. The slew rate can be adjustable to control power consumption in the liquid lens.

Tunable MEMS etalon devices comprising: a front mirror and a back mirror, the front and back mirrors separated in an initial pre-stressed un-actuated etalon state by a gap having a pre-stressed un-actuated gap size determined by a back stopper structure in physical contact with the front mirror and back mirrors, the etalon configured to assume at least one actuated state in which the gap has an actuated gap size gap greater than the pre-stressed un-actuated gap size; an anchor structure, a frame structure fixedly coupled to the front mirror at a first surface thereof that faces incoming light, and a flexure structure attached to the anchor structure and to the frame structure but not attached to the front mirror, and a spacer structure separating the anchor structure from the back mirror, and wherein the front mirror and the spacer structure are formed in a same single glass layer.

An apparatus for high dynamic range (HDR) modulation includes one or more lasers configured to transmit respective beams of laser light with a single color mode and a PLM optically coupled to the one or more lasers. The PLM is configured to modulate the laser light to produce a first modulated light. The apparatus also includes a phosphor optically coupled to the PLM and configured to receive at least a first portion of the first modulated light from the PLM and to emit a phosphor light with multiple color modes. At least one spatial light modulator (SLM) is also optically coupled to the phosphor and configured to modulate the multiple color modes in the phosphor light and the single color mode to project a second modulated light.

A wavelength-tunable interference filter includes: a first substrate where a first mirror and a first electrode are provided; a second substrate where a second mirror corresponding to the first mirror and a second electrode facing the first electrode are provided; and a bonding part bonding the first substrate and the second substrate together. The first substrate includes a moving part where the first mirror is arranged, a diaphragm part holding the moving part in such a way that the moving part is movable in the Z-direction, and an outer circumferential part provided outside of the diaphragm part. The diaphragm part includes a planar part having a uniform thickness, and a first slope part having a thickness in the Z-direction incrementing as it goes from the planar part toward the outer circumferential part. The first electrode is provided over a range from the planar part to the first slope part. An outer edge of the first electrode, which is an edge opposite to the first mirror, is located at the first slope part. The bonding part is provided over a range from a part of the first slope part to the outer circumferential part.

A light control system includes a housing, a controllable power source, a light source, and a plurality of cube-shaped tunable prisms. The controllable power source supplies at least four variable voltages. The light source is operable to emit a light beam. The cube-shaped tunable prisms are arranged in a manner so there are no gaps between adjacent tunable prisms. Each tunable prism receives a portion of the emitted light beam, each has a tunable deflection angle that is variable in two dimensions, and each is configured to optically steer the emitted light beam in the two dimensions based on the tunable deflection angle. Each tunable prism is further coupled to receive the four variable voltages. Each tunable prism comprises a liquid that varies the tunable deflection angle in two dimensions in response to the four variable voltages supplied thereto, to thereby deflect the light beam.