115 results about "Angular aperture" patented technology

The present invention provides improved angular aperture schemes for generating shaped beam spots having a desired geometric shape from rectangular, elliptical, and semi-elliptical apertures having one sharp edge. A sharper beam edge can be generated by offsetting the rectangular or elliptical aperture in combination with under or over focus. In the spherical aberration limit, under-focused semi-circle apertures provide a sharp, flat edge. The sharp edge can be made resolute enough for precision milling applications, and at the same time, the spot can be made large enough with enough overall current and current density to efficiently mill away material in either a production or laboratory environment. Depending on the particular beam spot that is desired, combinations of techniques including defocusing, aperture offsetting, and stigmation adjustment, can be used in both spherical aberration dominant and chromatic aberration dominant environments to achieve a desired beam for a desired application.

An integrated image sensor capable of determining the distance to objects contained in a scene including at least a set of first pixels and a set of second pixels, the first and second pixels being alternately distributed in an array, the first pixels having a different angular aperture than the second pixels.

Particle-beam apparatus is realized which is equipped with an aberration corrector capable of controlling the angular aperture of a particle beam after performing aberration correction. The corrector comprises four stages of electrostatic quadrupole elements, two stages of magnetic quadrupole elements for superimposing a magnetic potential distribution analogous to the electric potential distribution created by the two central stages of the electrostatic quadrupole elements, and four stages of electrostatic octupole elements for superimposing an octupole electric potential on the electric potential distribution created by the four stages of electrostatic quadrupole elements. An objective lens is located downstream of the corrector. An objective aperture is located upstream of the corrector. An angular aperture control lens is located downstream of the objective aperture to control the angular aperture of the probe hitting a specimen surface.

The invention relates to a refraction and reflection type large aperture and large field of view imaging system. The refraction and reflection type large aperture and large field of view imaging system is characterized in that a refraction type correction plate, a reflection type primary mirror and a refraction type correction mirror group are successively arranged along an optical axis from the outside to the inside; the central area of the second surface of the correction plate is plated with a reflective coating layer, and becomes a reflection type secondary mirror; an incident light beam irradiates to the reflection type primary mirror through the refraction type correction plate; the reflection type primary mirror reflects the incident light beam to the reflection type secondary mirror; and the reflection type secondary mirror reflects the light beam to the refraction type correction mirror group, and then the light beam passing through the refraction type correction mirror group is converged on a focal plane of an optical system. The refraction and reflection type large aperture and large field of view imaging system sets the refraction type correction plate within the focus of a reflection type spherical main mirror and takes the central area of the second surface of the correction plate as the reflection type secondary mirror and the diaphragm, thus having the advantages of ultra-short lens barrel and large field of view, and being able to be widely applied to the astronomy, aviation, security and protection, and other photoelectric imaging fields. The refraction and reflection type large aperture and large field of view imaging system can realize aberration reducing design for a 11DEG-15DEG field of view. However, the field of view for a traditional refraction and reflection type imaging system is only 3DEG-4DEG.

Complex spectral and angular diffractive optical elements in photosensitive materials based on Moiré pattern are proposed and demonstrated. The process is based on the recording of multiple volume Bragg gratings with controlled difference of the periods in the same volume of photosensitive material. Filters with ultra-narrow bandpass in the range of a few picometers to a few tens of picometers or apodized diffractive optical elements across large aperture are demonstrated. Several methods to fabricating such Moiré Bragg gratings are proposed. Experimental demonstration of a Moiré ultra-narrowband diffractive optical element in PTR glass is performed.

The invention discloses an ultra-high-definition zoom lens with a large aperture and an ultra wide angle. The ultra-high-definition zoom lens comprises a compensating lens group with negative total focal power and a zooming lens group with positive total focal power. The compensation lens group comprises a first lens, a second lens, and a third lens which are arranged successively from an object side to an image side. The zooming lens group comprises a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens which are arranged successively from the object side to the image side. The first lens and the sixth lens are both convex-concave lens with negative focal power. The second lens and the ninth lens are both biconcave lenses with negative focal power. The third lens is a convex-concave lens with positive focal power. The fourth lens and the seventh lens are both biconvex lenses with positive focal power. The fifth lens is a biconvex lens with positive focal power. The eighth lens is a concave-convex lens with negative focal power. The focal length magnification ratio of the ultra-high-definition zoom lens is greater than 4, does not generate a out-of-focus phenomenon when used in an environment from -40 to +80 degrees centigrade, can achieve effects that visible light and infrared light are confocal, resolution is more than 4K, and a maximum aperture can reach F1.3.

The invention relates to a device capable of generating uniform linear laser beams based on high-numerical aperture cylindrical lens focusing. The device is composed of a linear polarization laser light source, a spherical lens assembly, a rectangular aperture, a 1/2 wave plate, a discontinuous wave plate and a high-numerical aperture cylindrical lens. Light beams generated by the linear polarization laser light source are subjected to beam expansion and collimation which are performed by the spherical lens assembly, and then, rectangular linearly polarized light which is almost uniform and is arranged at the center of a light spot selectively passes through the rectangular aperture; the rectangular linearly polarized light emitted by the rectangular aperture passes through the 1/2 wave plate, and then, passes through or does not pass through the discontinuous wave plate; and after that, the rectangular linearly polarized light is focused by the high-numerical aperture cylindrical lens, and the uniform linear laser beams are generated at a focal plane. With the device which is of structural simplicity adopted, under the situations that the discontinuous wave plate is used or not used, the uniform linear laser beams of which the center is flat-topped can be obtained at the focal plane through simply rotating the 1/2 wave plate and changing the numerical aperture of the high-numerical aperture cylindrical lens, wherein the uniform linear laser beams can be used for linear scanning microscopic imaging, and micro-nano materials processing and detection.

A device measures, by diffraction, the sizes of substantially spherical particles, in particular opaque drops. This device includes a lens (46) and prisms (49, 50, 51) for receiving the light diffracted by the particles (12), lighted by a light beam, for splitting this diffracted light into annular concentric areas and for concentrating the various parts of the diffracted light, corresponding to these areas, into separated points (24, 26, 28). The light intensifies in these points are detected and the sizes of particles are determined on the basis of these light intensities. The angular aperture of the concentric areas is adjusted according to a pattern which optimizes the discrimination of particle sizes.

The collet is formed by a metal band (10) whose inner contour (11) delimits the recesses (11a, 11b, 11c) for driving the collet onto a balance staff (2) and whose outer contour (12) includes a function point (4) between the collet and the balance spring (9) located at the end of an arm (14) at a distance R from the centre 0 of the staff (2) greater than that of any other point (6, 8, 13, 15, 17) of the outer contour (12). It is characterised in that the inner contour (11) includes a discrete number of points of contact (1, 3, 5, 7) with the staff (2) distributed along identical or different angular apertures α and in that width “I” of the band (10) varies such that the compression forces of the contact points (1, 3, 5, 7) on the staff (2) do not substantially alter the distance R after driving in, leading to a friction torque allowing angular orientation of the collet on the staff (2) and not introducing any unbalance.

Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.

An electron microscope is offered which facilitates aberration correction even during high-magnification imaging. The microscope has a spherical aberration corrector, a transfer lens system mounted between the corrector and an objective lens, an aperture stop mounted in a stage preceding the corrector so as to be movable relative to the optical axis, and an angular aperture stop mounted at or near the principal plane of the transfer lens system movably relative to the optical axis to adjust the angular aperture of the electron beam.

The invention relates to a trifocal artificial lens and a manufacturing method thereof. The front surface and/or the rear surface of an optical part of the trifocal artificial lens are/is designed through an aspheric surface, and are/is of a diffraction ladder structure, the heights of every two adjacent diffraction ladders are alternately changed, and in a standard human eye model, the longitudinal spherical aberrations of the trifocal artificial lens at the retina under the 0-6 mm clear aperture are all negative values; meanwhile, as the clear aperture is increased, the absolute values of the longitudinal spherical aberrations are increased, and the longitudinal spherical aberrations of the trifocal artificial lens at the retina under the 0-6 mm clear aperture are within minus 0.26 mm tominus 0.85 mm. By means of the trifocal artificial lens, far, middle and near full-range vision is provided, and vision loss does not exist within any distance. Compared with multifocal and trifocallenses in the prior art, the contrast sensitivity of the trifocal artificial lens in the middle-range vision is obviously improved.

The invention discloses a method for automatically controlling received power in an FSO system. In a receiving device of a detector of a free-space optics communication system, the received light power is controlled by a method of automatically extending to control a received angular aperture; the control of the received angular aperture is realized by an aperture adjustable diaphragm; a light power sampling system samples the detector regularly, and sample values are input to a microprocessor, compared with a received light power range value stored in the microprocessor, and processed; when the received light power range value is smaller than a fixed value, the aperture of the diaphragm is increased, and when the received light power range value is greater than the fixed value, the aperture of the diaphragm is decreased; and a processing result is used to control a stepping motor to move the position of one end of the diaphragm so as to change the clear aperture of the diaphragm and control the received light power range. By adjusting the detection light intensity, the light power change range of the receiving end is reduced effectively and the stability and reliability of the system are further strengthened.

An electron beam applying apparatus includes: a thermal field emission type electron source emitting an electron beam; an electrostatic lens disposed immediately below the electron source and acting as a condensing electrode for condensing the electron beam in a first angular aperture emitted by the electron source in a second angular aperture smaller than the first angular aperture; a condenser lens disposed on a downstream side of the electrostatic lens and condensing the electron beam condensed in the second aperture angel by the electrostatic lens in a crossover point; and an objective lens disposed on a downstream side of the condenser lens and condensing the electron beam condensed in the crossover point by the condenser lens on the surface of the material.

The invention provides a manufacturing process of an ultra-low carbon X42 steel grade high frequency straight welding tube, which adopts the steps of welding a reel tail of a front reel and a reel head of a back reel of the ultra-low carbon X42 steel grade high frequency straight welding tube with C content of 0.33-0.06% through steel by adopting consumable electrode gas protection protected by carbon dioxide gas; adopting a cage forming method to enable welded strip steel to be formed into a pierced billet; adjusting output power of a radio-frequency induction coil; extruding the pierced billet with the extrusion quantity of 1-4.5% * D, wherein the D is the external diameter of an end product tube, and the angular aperture theta is controlled between 3 degrees and 6 degrees; welding to be the high frequency straight weld tube with the welding speed of 14-20m/min; conducting normalizing heat treatment on welding joints with the normalizing heat treatment temperature of 950+-20 DEG C, slowly cooling the welding joints to 400 DEG C in air after normalizing, and enabling the welding joint temperature to drop to the temperature below 80 DEG C after water cooling. The performance of the welding tube achieves the levels that the tensile strength of the welding joints is no less than 415 MPa, unit value of charpy ballistic work of the welding joints is no less than 40J, and mean value of the welding joints is no less than 40J.

The invention relates to a medium-wave infrared refrigerated lens with long focal length and large aperture. A front unit A and a rear unit B are sequentially arranged in an optical system of the lens along the left-to-right light incidence direction, the front unit A is sequentially provided with a protective sheet, a positive lens A-1, a positive lens A-2 and a negative lens A-3, and the rear unit B is sequentially provided with a positive lens B-1 and a positive lens B-2. The medium-wave infrared refrigerated lens has the characteristics of high imaging quality, high spatial resolution, small volume, vibration and impact resistance, and the like; in an optical structure, the optical focal power of the front unit A and the rear unit B is allocated reasonably; the rear unit B adopts two aspheric faces, so that the lens can reach the performance indexes of long focal length, large aperture and simple and compact structure; in an optical design, the temperature compensation and far-close compensation are realized through the movement of the positive lens B-1, so as to guarantee the use requirements of the lens in high- and low-temperature environments; the lens can be adapted to a medium-wave infrared refrigerated detector (320*256, 30 microns) so as to carry out live recording and tracking tasks.

The invention provides a parameter calibration system of an acousto-optic tunable filter, comprising a controlling and processing computer, an optical grating monochrometer, a mercury argon gas light source, an optical path section, a precision electronic control rotary table, a high-precision radio frequency driver, a photomultiplier, a CCD light distribution detector and a precision electronic control translation guide rail; and the optical path section is mainly composed of a reflecting mirror, a semi-transparent semi-reflective lens, a Glan-Taylor prism, a collimating lens, an aperture and a focusing lens. The invention has complete calibrating system and high calibrating precision, can carry out automatic calibration on parameters like AOTF light beam incident angle, the off-axis angle theta alpha, the angular aperture delta, wavelength response function, wavelength frequency tuning relation, deflection angle beta and the like, is applicable to the index inspection of the AOTF product, the research of AOTF light spectrum and imaging characteristics, and provides technical parameters for the integration of AOTF spectrometer.

Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.

A glass composition suitable for producing a graded-refractive-index rod lens having an angular aperture of 16-20° without containing lead or thallium and a graded-refractive-index rod lens produced from the composition are provided.

The composition is a base glass composition for graded-refractive-index rod lenses, characterized by comprising, in terms of % by mole, 20≦SiO₂≦52, 1≦B₂O₃≦30, 12≦Li₂O≦18, 8≦Na₂O≦15, 0≦MgO≦15, 0≦SrO≦10, 0≦BaO≦10, 0≦ZnO≦15, 0≦TiO₂≦15, 0≦Nb₂O₅≦5, 0≦Ta₂O₅≦5, and 3<Bi₂O₃≦13, provided that 45≦SiO₂+B₂O₃≦65, 9≦MgO+ZnO+TiO₂≦25, and 0≦Nb₂O₅+Ta₂O₅≦5, and by containing substantially no lead and substantially no thallium.

The invention provides an infrared optical system and an optical device. By adoption of a coaxial catadioptric optical structure, the long focal length and large relative aperture imaging of medium wave or long wave infrared band can be realized, and the detection capability of the infrared optical system is remarkably improved. In addition, the miniaturization of the large aperture and long focallength infrared optical system is realized by utilizing a high gradient and large numerical aperture primary mirror, a high magnification afocal light path, and a 'hair bun type' light path layout; the thickness of the optical system in the optical axis direction is only 0.20~0.60 of the focal length.

The invention discloses a plasma filter with an embedded rectangular cavity based on an MIM waveguide. The plasma filter belongs to the field of micro-nano optoelectronics. The filter of a metal-dielectric-metal rectangular waveguide is constructed by adopting an aperture coupling method. According to the plasma filter, a metal thin film is made of a metal silver material, the overall prepared metal thin film is square, and an incident waveguide, a rectangular aperture and a rectangular resonant cavity are formed in the metal thin film in a hollowed manner. The plasma filter adopts the rectangular resonant cavity to realize resonance coupling of surface plasmon polaritons SPP and the resonant cavity through connection of the rectangular aperture and the optical waveguide. The plasma filterhas the advantage of being capable of realizing frequency selection property of the filter through adjusting the length and width of the rectangular resonant cavity, the width of the rectangular aperture and the like.

The invention relates to sonar transmission means and in particular to transmission means for achieving omnidirectional acoustic transmission. The invention relates to a method for achieving omnidirectional transmission using of a towed linear antenna of length L greater than the wavelength λ of the signal transmitted. The antenna has a plurality of P projectors. The spacing between projectors is substantially less than λ/2. The method according to the invention includes applying, to each projector, a transmit signal coming from a common transmit signal. The common signal is assigned a delay, the expression for which follows a law containing a non-linear term as a function of the position of the projector in the antenna. Application of this law allows the angular aperture of the transmission pattern to be modulated. The invention makes it possible in particular to produce sonar detection systems comprising transmit and receive antennas having substantially identical diameters, which can be reeled onto the same winch without it being necessary to separate them.