An apparatus comprises a first mirror; a second mirror; a modulation layer positioned between the first mirror and the second mirror and comprising a plurality of modulation regions; a diffraction layer positioned between the modulation layer and the second mirror, and an input port admitting a light beam into the apparatus. The light beam passes through the diffraction layer and is modulated by the modulation layer to create a first modulated beam before being reflected by the first mirror, the first mirror reflecting the first modulated beam toward the second mirror, the second mirror reflecting the first modulated beam toward the modulation layer to be modulated for at least a second time.

A colored structure representing a back side-reflection color with metallic luster and high chroma when observed in a substrate incident mode greatly enhances light absorbance at a specific wavelength using a resonance structure in which a light absorbing material is inserted between a transparent substrate and an upper mirror layer. The colored structure controls metallic luster and texture of a high-chroma color from gloss-semi-gloss-matte texture in various aesthetic ways including introducing a haze surface structure in which light scattering occurs on at least one surface of the transparent substrate.

A particle detector includes at least one resonant cavity partially formed at least by a first reflector, a second reflector disposed at a distance from the first reflector and a channel located between the first and second reflectors, the channel being intended to receive at least one fluid comprising particles and to receive at least one light radiation; and at least one detection system having at least one photodetector. The particle detector is configured so that a portion of the light radiation present in the channel escapes from the cavity throughout the second reflector and reaches the detection system, thereby enabling the at least one photodetector to detect leakage of the cavity. The second reflector is a photonic crystal membranes PCM based reflector.

Implementations are described herein for isolating mirrors and/or other potentially-vulnerable components of multi-pass optical systems from samples being analyzed, while mitigating interference and/or reduction in optical power. In one implementation, an apparatus may include: an optical cell with one or more passages, the one or more passages provided for introducing a sample into an interior of the optical cell for analysis and for removing the sample from the interior; a first mirror with a first reflective surface that faces the interior of the optical cell; one or more additional mirrors with one or more corresponding additional reflective surfaces that face the first reflective surface of the first mirror; and a wedge-shaped optical element positioned between the first mirror and the interior of the optical cell.

According to various embodiments, a direct magnetic gradiometer having intrinsic subtraction of rotation signals from two oppositely polarized atomic ensembles within a single multi-pass cell is disclosed. The gradiometer includes three convex spherical mirrors aligned in a V-shape geometry. The three convex spherical mirrors include a front mirror and two back mirrors. The gradiometer further includes a probe laser beam. The laser beam is configured to be initially focused at a near-zero angle into a hole at a center of the front mirror such that the laser beam expands at the back mirrors and nearly overlaps with itself while undergoing multiple reflections between the front and back mirrors. The laser beam is further configured to be refocused to the front mirror at different spots in a number equal to half of total beam passes before exiting.

A telephoto optical imaging system and zoom camera apparatus. The telephoto optical imaging system includes, sequentially from an object side to an image side along an optical axis, a first lens having positive refractive power, a second lens having negative refractive power, an optical path turning prism, and a triangular prism. Distance T from the object-side surface of the first lens to an imaging plane of the telephoto optical imaging system in a normal direction of the imaging plane and the total effective focal length F1 of the telephoto optical imaging system satisfy T/F1<0.6. The zoom camera apparatus includes the telephoto optical imaging system and a short-focus optical imaging system arranged in parallel with the telephoto optical imaging system. A total effective focal length F1 of the telephoto optical imaging system and a total effective focal length F2 of the short-focus optical imaging system satisfy F1/F2>5.

An optical pulse stretcher includes a first delay optical system including a plurality of concave toroidal mirrors; and a beam splitter including a first surface and a second surface, causing a part of pulse laser light incident on the first surface to be transmitted in a first direction and output as a first beam and another part thereof to be reflected in a second direction and enter the first delay optical system, and causing a part of pulse laser light incident on the second surface from the first delay optical system to be reflected in the first direction and output as a second beam.

Optical sensors and particularly gimbaled optical sensors transmit an active signal at a given wavelength(s) and receive passive signals over a range of wavelengths and the active signal in a common aperture. The sensor includes a Tx/Rx Aperture Sharing Element (ASE) configured with an annular region that couples an active signal having a ring-shaped energy distribution to the telescope for transmission and a center region that couples the passive emissions and the returned active signal to the detector. A beam shaping element such as an Axicon lens, LCWG, Risley Prism, Unstable Optical Resonator or MEMS MMA may be used to form or trace the ring-shaped active signal onto the annular region of the ASE. A focusing optic may be used to reduce the divergence of the active signal so that it is collimated or slightly converging when transmitted such that the returned active signal approximates a spot. A filter wheel may be positioned behind the ASE to present separate passive and active images to the detector. These optical sensors may, for example, be used with guided munitions or autonomous vehicles.

Systems and methods providing non-contact confinement and vibration isolation of electromagnetic resonators are provided herein. In certain embodiments, a device includes an electromagnetic resonator body. The device further includes a frame enclosing a volume, wherein the electromagnetic resonator is located within the volume. Additionally, the device includes a plurality of body electrodes mounted on the electromagnetic resonator body. Also, the device includes a plurality of frame electrodes mounted on the frame. Moreover, the device includes an electrode controller, wherein the electrode controller drives the plurality of frame electrodes to isolate the electromagnetic resonator body from vibrations to the frame by allowing a rattle space between external surfaces of the electromagnetic resonator body and internal surfaces of the frame to approach but be greater than zero.

A vapor cell which can increase the S/N ratio of light as a signal and has high accuracy and a vapor cell manufacturing method are provided. The vapor cell includes: a reflection space (14) provided so as to be able to store a gas containing an alkali metal atom; and an incident light reflection surface, an in-plane reflection portion (17), and an emission light reflection surface provided inside the reflection space (14). The incident light reflection surface has an elevation angle of 45° from an optical path plane so that the incident light incident from a predetermined external direction is reflected in the optical path plane that is perpendicular to the incident light. The in-plane reflection portion (17) has a reflection surface that reflects the reflected light from the incident light reflection surface, the reflection surface being substantially perpendicular to the optical path plane so that the reflected light from the incident light reflection surface is reflected in the optical path plane once or multiple times. The emission light reflection surface has an elevation angle 45° from the optical path plane so that the reflected light from the in-plane reflection portion (17) is reflected in a direction substantially perpendicular to the optical path plane and an emission light is emitted to the outside.