Abstract: Techniques are described herein that are capable of adjusting a notch frequency of an adaptive notch filter (“filter”) to track a resonant frequency of a slow scan MEMS mirror (“mirror”). For instance, an adaptive feedback may be configured to determine one or more resonant frequencies of the mirror based at least in part on a frequency response of an output signal that is proportional to movement of the mirror. The adaptive feedback may be further configured to adjust at least one notch frequency of the filter to track at least one respective resonant frequency of the mirror. The filter may be configured to modify a magnitude of a frequency response of a combination of the filter and the mirror to be substantially constant by suppressing the at least one notch frequency in a frequency response of the mirror.

Abstract: Holographic energy directing systems may include a waveguide array and a relay element. Disclosed calibration approaches allows for mapping of energy locations and mapping of energy locations to angular direction of energy as defined in a four-dimensional plenopic system. Distortions due to the waveguide array and relay element may also be compensated.

Abstract: An electronic device includes at least one optical lens assembly. The optical lens assembly includes four lens elements, and the four lens elements are, in order from an outside to an inside, a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element has an outside surface being convex in a paraxial region thereof. The second lens element has an inside surface being convex in a paraxial region thereof. The fourth lens element has an inside surface being concave in a paraxial region thereof, wherein at least one of an outside surface and the inside surface of the fourth lens element includes at least one critical point in an off-axis region thereof.

Abstract: A sample observation device includes a light source, an illumination optical system, an observation optical system, a detector, a processor, and a drive controller. The illumination optical system includes a condenser lens and an aperture, and the observation optical system includes an objective lens and a light attenuation member. The light attenuation member and the aperture are conjugate. The aperture includes an aperture region, and the light attenuation member includes a light attenuation region. A size of the aperture region, a position of the aperture region, a size of the light attenuation region, and a position of the light attenuation region are set such that a predetermined state is generated. The processor determines light quantity of light received with the detector. The drive controller changes an interval between a sample and the objective lens on the basis of the light quantity such that the light quantity becomes minimum.

Abstract: A display device may comprise a transmittance control structure having a variable transmittance and a mirror type display panel disposed on a rear surface of the transmittance control structure. The mirror type display panel may comprise a substrate, a display member disposed on the substrate, the display member including a light emission region, a first transmission region, and a peripheral region surrounding the light emission region and the first transmission region, and a reflective member facing the substrate with respect to the display member, the reflective member including an opening region corresponding to the light emission region, a second transmission region corresponding to the first transmission region, and a reflective region surrounding the opening region and the second transmission region.

Abstract: An imaging optical system consists of, in order from a magnification side: a first optical system that forms an intermediate image on a position conjugate to a magnification side imaging surface; and a second optical system that re-forms the intermediate image on a reduction side imaging surface. The first optical system includes at least two focusing lens groups that move with different loci during focusing. The imaging optical system satisfies predetermined conditional expressions relating to the focusing lens groups.

Abstract: An optical lens assembly includes five lens elements and provides a TTL/EFL<1.0. In an embodiment, the focal length of the first lens element f1<TTL/2, an air gap between first and second lens elements is smaller than half the second lens element thickness, an air gap between the third and fourth lens elements is greater than TTL/5 and an air gap between the fourth and fifth lens elements is smaller than about 1.5 times the fifth lens element thickness. All lens elements may be aspheric.

Abstract: An imaging optical lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has an object-side surface being convex in a paraxial region. The second lens element with negative refractive power has an object-side surface being concave in a paraxial region. The third lens element has an object-side surface and an image-side surface being aspheric. The fourth lens element with negative refractive power has an object-side surface being concave and an image-side surface being concave in a paraxial region, wherein the image-side surface has convex shape in an off-axis region, and the two surfaces thereof are aspheric. The fifth lens element with positive refractive power has an object-side surface and an image-side surface being both aspheric.

Abstract: The invention relates to a metasurface lens using a planar array of elementary resonators, each elementary resonator being the shape of a cross the arms of which are of unequal length. The phase shift applied by an elementary resonator is dependent on its orientation in the plane of the lens, the orientation of the various elementary resonators being determined depending on the shape of the desired wavefront. Such a lens has a substantially uniform transmission-coefficient distribution and a low chromatic aberration. Furthermore, it has a very good spectral selectivity.

Abstract: A folded telephoto lens system may include multiple lenses with refractive power and a light path folding element. Light entering the camera through lens(es) on a first path is refracted to the folding element, which changes direction of the light on to a second path with lens(es) that refract the light to form an image plane at a photosensor. At least one of the object side and image side surfaces of at least one of the lens elements may be aspheric. Total track length (TTL) of the lens system may be 14.0 mm or less. The lens system may be configured so that the telephoto ratio (TTL/f) is less than or equal to 1.0. Materials, radii of curvature, shapes, sizes, spacing, and aspheric coefficients of the optical elements may be selected to achieve quality optical performance and high image resolution in a small form factor camera.

Abstract: Aspects of this disclosure concern controllers and control methods for applying a drive voltage to bus bars of optically switchable devices such as electrochromic devices. Such devices are often provided on windows such as architectural glass. In certain embodiments, the applied drive voltage is controlled in a manner that efficiently drives an optical transition over the entire surface of the electrochromic device. The drive voltage is controlled to account for differences in effective voltage experienced in regions between the bus bars and regions proximate the bus bars. Regions near the bus bars experience the highest effective voltage. In some cases, feedback may be used to monitor an optical transition. In these or other cases, a group of optically switchable devices may transition together over a particular duration to achieve approximately uniform tint states over time during the transition.

Abstract: An optical system for overlaying a first image of a scene and a second image includes a first imaging device providing the first image, a second imaging device with an image display and collimation optics providing the second image, and a waveguide. The waveguide has a first diffraction grating configured to receive the first image, a second diffraction grating configured to receive the second image, and a guide portion disposed between the first diffraction grating and the second diffraction grating configured to convey the second image to the first grating. The first diffraction grating is configured to overlay the first image and the second image.

Abstract: A related-art optical element using an antireflection film having a layer having an uneven structure or a porous layer has involved a problem in that the performance of the antireflection film is degraded by SO2 in an exhaust gas. In view of the problem, provided are an optical element in which a positive ion spectrum of a surface of an antireflection film measured by TOF-SIMS has a peak of CmHnN+, where m represents an integer of 1 or more to 8 or less, and n represents an integer of 2 or more to 16 or less, and a method of producing the element.

Abstract: Laser or narrow band light sources (e.g., red, green, and blue) are utilized to form left (e.g., R1, G1, B1) and right (e.g., R2, G2, B2) images of a 3D projection. Off-axis viewing of the projections which has the potential to cause crosstalk and/or loss of energy/brightness in any channel or color, is eliminated (or reduced to only highly oblique viewing angles) via the combined use of any of guard bands between light bands of adjacent channels, curvature of viewing filters, and selection of passband wavelengths that maximize usability of the passband as it “shifts” due to varying or increasing angles of off-axis viewing. Implemented with any number of light sources, the light sources selected may also be converted to showing 2D images where the additional light sources are utilized to affect a desirable increase in color gamut.

Abstract: The apparatus and design method of a subzonal multifocal diffractive (SMUD) lens is described herein. The apparatus includes a plurality of annular concentric zones. Each zone are further divided into at least two subzones, where the division of the subzones is arbitrary, but the division is consistent with respect to radius squared r2 across all zones. The subzone phase profile is independent with each other within the same zone, and can be optimized to achieve a desired splitting ratio among all foci.

Abstract: A freeform surface off-axial three-mirror imaging system comprising a primary mirror, a secondary mirror, a tertiary mirror, and a detector. The secondary mirror comprises a first freeform surface and a second freeform surface. Each reflective surface of the primary mirror, the first freeform surface, the second freeform surface and the tertiary mirror is an xy polynomial freeform surface. The freeform surface off-axial three-mirror imaging system comprises a first effective focal length and a second effective focal length different from the first effective focal length.

Abstract: Variable transmission covering systems that can be used, for example, to control the amount of light passing through a window in a building. Using transmissive electrophoretic media that can switch between a first and second optical state, the invention can be used to change the color and/or transmissivity of a structure (or structures) that is placed in front of an object. In some embodiments, the variable transmission system can change transmission and color on command.

Abstract: A camera module includes a housing accommodating a lens module, a driving unit including a magnet disposed on the lens module and a coil disposed to face the magnet, a yoke generating attractive force with the magnet, a first ball member accommodated in a first receiving space disposed between the lens module and the housing, and pressed by the attractive force, and a second ball member accommodated in a second receiving space disposed between the lens module and the housing, and pressed by the attractive force. A length of the first receiving space in an optical axis direction is different from a length of the second receiving space in the optical axis direction.

Abstract: An optical filter may include a substrate made of a material including an optically transparent matrix material and nano-photonic material with icosahedral or dodecahedral symmetry dispersed in the matrix material.

Abstract: A laser pointer may include a laser beam emission unit to emit a laser beam; a housing; a shake detection sensor; a shake correction mechanism to change a direction of the laser beam, and a movable member including an accommodation portion arranged to face a window formed in one surface of the fixed body. The shake detection sensor is housed in the movable member, the fixed body, or the housing. The shake correction mechanism may include an attachment adjusting member housed together with the laser beam emission unit in the accommodation portion while surrounding a side periphery of the laser beam emission unit; a movable member support mechanism; and a movable member drive mechanism.