47results about How to "Avoid aberrations" patented technology

A bio-compatible corneal ring for myopic correction and accommodation for presbyopia. The corneal ring is made from a bio-compatible material with a lens body having an inner and outer circular edge. The inner circular edge forms an opening in the lens body. The posterior surface of the lens body has a uniform radii of curvature between the inner and outer circular edges. The anterior surface has two radii of curvatures providing for correction of myopia. The first radii of curvature extends from near the outer circular edge to a junction point before the inner circular edge. The second radii of curvature extends from the junction point and continues to the inner circular edge. The inner and outer circular edges have a thickness of less than about 0.020 mm, but preferably are about 0.010 mm or less.

The present invention provides a wide-angle imaging lens assembly comprising, in order from an object side to an image side: a first lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a second lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power; a fourth lens element with negative refractive power having a concave image-side surface; and a fifth lens element with positive refractive power; wherein the two lens elements with refractive power closest to the object side are the first lens element and the second lens element; and wherein the number of lens elements with refractive power does not exceed six.

Disclosed is a lens system installed in a mobile communication terminal, comprising: a first lens including at least one aspherical plane and having a positive refractivity; a perforated iris separated from the first lens by a designated distance for preventing unnecessary incident light from being incident onto an optical system; a second lens separated from the perforated iris by a designated distance, including at least one aspherical plane and having a positive refractivity; and a third lens separated from the second lens by a designated distance, including at least one aspherical plane and having a negative refractivity, wherein the first lens, the perforated iris, the second lens and the third lens are arranged sequentially from a subject, and the perforated iris is located between the first lens and the second lens.

One modified source-conversion unit and one method to reduce the Coulomb Effect in a multi-beam apparatus are proposed. In the modified source-conversion unit, the aberration-compensation function is carried out after the image-forming function has changed each beamlet to be on-axis locally, and therefore avoids undesired aberrations due to the beamlet tilting / shifting. A Coulomb-effect-reduction means with plural Coulomb-effect-reduction openings is placed close to the single electron source of the apparatus and therefore the electrons not in use can be cut off as early as possible.

An arrangement, for light sheet microscopy, including: a sample vessel, for receiving a medium containing a sample, oriented with respect to a plane reference surface; illumination optics with an illumination objective for illuminating the sample with a light sheet; and detection optics with a detection objective. The optical axis of the illumination objective and the light sheet lies in a plane which forms a nonzero illumination angle with the normal of the reference surface. The detection objective has an optical axis that forms a nonzero detection angle with the normal of the reference surface. The arrangement also includes a separating-layer system for separating the sample-containing medium from the illumination and detection objectives. The separating-layer system contacts the medium with an interface parallel to the reference surface. The illumination angle and detection angle are predetermined based on numerical apertures of the detection objective and of the illumination objective, respectively.

The invention relates to an LED visible light communication system and a light receiving antenna. The light receiving antenna comprises a converging and reflecting unit with converging and reflecting functions and a photoelectric detector arranged at a focal point of the converging and reflecting unit, wherein the converging and reflecting unit is used for converging light signals which are transmitted by an LED light source and carry communication information at the focal point, so that the photoelectric detector receives and analyzes the light signals and recovers the communication information. The light receiving antenna has the beneficial effects that convergence and reception of the light signals are achieved by the light receiving antenna, thus recovering the communication information carried in the light signals transmitted by the LED light source and achieving LED visible light communication; the reflective mirror with the reflecting surface being a paraboloid is adopted as the converging and reflecting unit, thus being capable of easily expanding the light receiving area, achieving large-range light receiving, being beneficial to detection of dim light, improving the sensitivity, avoiding impact of surrounding stray light and ensuring good anti-jamming effect; and a Fresnel prism is adopted to achieve reflection and convergence of light and convergence of reflective light with the help of a reflecting plate, thus reducing the volume of the receiving antenna.

An exposure apparatus includes a projection optical system, which projects a pattern of a mask onto a prescribed exposure area on a substrate at a prescribed projection magnification. The optical axis center of the projection optical system is set to a position different from that of the center of the projection area onto which the pattern is projected. The exposure apparatus further includes a magnification modification device, which modifies the projection magnification of the projection optical system; a calculation device, which calculates a shift length of the center of the projection area associated with modification of the projection magnification; and a correction device, which corrects the position information of the exposure area based on the shift length of the center of the projection area.

The invention relates to a bent type zoom optical system comprising a positive first lens group having a reflecting member and remaining fixed upon zooming and a second lens group adapted to move upon zooming, and having a high zoom ratio and a short entire-length, and an imaging apparatus or the like incorporating the same. The zoom optical system comprises the positive first lens group G1 adapted to remain fixed upon zooming and the negative second lens group adapted to move upon zooming. The positive first lens group G1 comprises, in order from the object side, a negative single lens, a reflecting member P and a positive lens unit. The zoom optical system satisfies condition (1) for prevention of fluctuations in the entrance pupil position, condition (2) about the focal length of the first lens group G1, and condition (3) for putting in order the shape of the negative single lens in the first lens group G1.

An imaging lens is essentially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens of a biconcave shape; a third lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; a fourth lens having a negative refractive power and a concave surface toward the object side; and a fifth lens having a negative refractive power and a concave surface toward the image side, provided in this order from the object side. The imaging lens satisfies predetermined conditional formulae.

The embodiment of the present application discloses a screen under biometric identification device and an electronic device. The under-screen biometric device includes: a micro hole disposed under thedisplay screen for transmitting reflected light from above the display screen to the aspherical transmission structure; and an aspherical transmission structure disposed under the micro hole An aspherical mirror is provided for transmitting the reflected light to the photosensor array by the aspherical mirror; and a photosensor array for detecting the reflected light. The technical solution of the embodiment of the present application can improve the efficiency of the biometric recognition under the screen.

An exposure apparatus includes a projection optical system, which projects a pattern of a mask onto a prescribed exposure area on a substrate at a prescribed projection magnification. The optical axis center of the projection optical system is set to a position different from that of the center of the projection area onto which the pattern is projected. The exposure apparatus further includes a magnification modification device, which modifies the projection magnification of the projection optical system; a calculation device, which calculates a shift length of the center of the projection area associated with modification of the projection magnification; and a correction device, which corrects the position information of the exposure area based on the shift length of the center of the projection area.

The invention discloses a telecentric optical structure-based transmission-type digital holographic microscopic imaging device. By a telecentric optical structure, two beams of parallel light, namely object light and reference light intervene on an imaging plane of a camera to form an interference pattern, so that aberration in a conventional digital holographic microscopic imaging device can be avoided; the accuracy of a system is greatly improved; other complicated physical or aberration compensation calculation processes are not needed; the imaging speed is improved; and the late calculating and processing complexity is lowered.

A method and system for spectroscopic ellipsometry employing reflective optics to measure a small region of a sample by reflecting radiation (preferably broadband UV, visible, and near infrared radiation) from the region. The system preferably has an autofocus assembly and a processor programmed to determine from the measurements the thickness and / or complex refractive index of a thin film on the sample. Preferably, only reflective optics are employed along the optical path between the polarizer and analyzer, a sample beam reflects with low incidence angle from each component of the reflective optics, the beam is reflectively focused to a small, compact spot on the sample at a range of high incidence angles, and an incidence angle selection element is provided for selecting for measurement only radiation reflected from the sample at a single, selected angle (or narrow range of angles). The focusing mirror preferably has an elliptical shape to reduce off-axis aberrations in the focused beam. Some embodiments include both a spectrophotometer and an ellipsometer integrated together as a single instrument. In such instrument, the spectrophotometer and ellipsometer share a radiation source, and radiation from the source can be focused by either the spectrophotometer or the ellipsometer to the same focal point on a sample. Preferred embodiments of the ellipsometer employ a rotating, minimal-length Rochon prism as a polarizer, and include a spectrometer with an intensified photodiode array to measure reflected radiation from the sample, and a reference channel (in addition to a sample channel which detects radiation reflected from the sample).

The present invention provides a wave of correction devices, which include lens, cooling cavity, driver, water pipe, base, water inlet, outlet, and support;The other end is fixed with the base; one end of the water pipe is connected to the cooling cavity, and the other end is fixed with the base; the base is fixed on the support;The water pores on the seat correspond to one -to -one pores.This scheme can load different loads on the drive according to the application requirements. The mirror movement moves up and down under the action of the driver, so that the mirror surface deforms, thereby correcting the wave surface.The influence, avoid the introduction of unnecessary extra extension.

An anti-shake device for positioning an image-capturing unit in an optical instrument. A base includes a shaft pillar. A clamp unit includes a first clamping arm and a second clamping arm. The first and second clamping arms pivot to the shaft pillar of the base and detachably clamp the image-capturing unit. A drive unit is connected to the base and includes a driven member driving the first and second clamping arms of the clamp unit to rotate and shifting between a first mode and a second mode. The first and second clamping arms are separated from each other and the image-capturing unit when the driven member is in the first mode. The first and second clamping arms close and clamp the image-capturing unit when the driven member is in the second mode.

The invention relates to an LED visible light communication system and a light receiving antenna. The light receiving antenna comprises a photoelectric conversion device and a light convergence device, wherein the photoelectric conversion device and a light source are arranged on the same side of the light convergence device; and the light convergence device is used for converging the incident light emitted by the light source on the photoelectric conversion device. The light receiving antenna has the beneficial effects that as the photoelectric conversion device and the light source are arranged on the same side of the light convergence device, the influence of stray light on a detector can be avoided and the anti-jamming effect is good; the aberration influence in the prior art can be avoided, thus being beneficial to detection of dim light; the inconsistency between the photoelectric conversion device and the response time thereof can be balanced; besides, the light source can be used for illumination, thus achieving multi-functionalization.

The variable-power optical system is provided and includes a first lens group having a negative refractive power, a stop, and a second lens group having a positive refractive power, in order from an object side. The first lens group includes a first sub lens group having three negative meniscus lenses and a second sub lens group having a biconcave lens and a positive lens, in order from the object side. The second lens group includes a first positive lens arranged closest to the object side and having at least one aspheric surface and a second positive lens arranged immediately after the image side of the first positive lens. When the absolute value of the focal length of the first lens group is |f1| and the focal length of the entire system at a wide angle end is fw, the Conditional expression: 1.9<|f1| / fw<3.6 is satisfied.

The invention discloses a reflective digital holographic microscopic imaging device based on a telecentric optical structure. The reflective digital holographic microscopic imaging device adopts the telecentric optical structure, so that two parallel beams of object light and reference light interfere with each other to form an interferogram on an imaging plane of a camera, thereby avoiding aberration in the traditional digital holographic microscopic imaging device, greatly increasing system accuracy degree, and reducing complexity of later calculation and processing since other complicated physical or computing aberration compensation processes are not needed.

The present invention is directed to an inner focusing macro lens that has a large aperture ratio as expressed by 2.5 or even smaller in F-number and still remains compact, and that is adapted to compensate for spherical aberration, astigmatism, and comatic aberration during photographing throughout the entire object distance ranging from infinity to proximity for an up to 1:1-magnification image. The inner focusing macro lens has the leading or first lens group of positive refractivity, the second lens group of negative refractivity, the third lens group of positive refractivity, and the trailing lens set succeeding to the third lens group in sequence from a position closest to an object being photographed. During focusing from a point infinitely far to that as proximal as desired, the first lens group is static while the second lens group is moved toward the imaging plane, and the third lens group is moved toward the object. The first lens group has at least four lens pieces of comprehensively positive refractivity and at least one lens piece of negative refractivity, and three of the lens pieces closest to the object in the first lens group are of positive refractivity.

The invention discloses a human eye laser interference fringe visual perception learning and training instrument which comprises a light source, an optical system, an interference fringe frequency regulating device, an interference fringe contrast regulating device, an interactive device and a computer, wherein coherent light emitted by the light source passes through the optical system to obtaintwo beams of coherent light and one beam of non-coherent background light, the two beams of coherent light converges at the pupil, and two generated point light sources are in interference, thereby generating interference fringes at the eye ground; the interference fringe frequency regulating device is used for regulating the interval between the two beams of coherent light converging at the pupil, thereby regulating the frequency of the interference fringes; and the interference fringe contrast regulating device is used for regulating the overall contrast of the interference fringes. The instrument disclosed by the invention can directly avoid the influence of aberration and diffraction of a human eye optical system, has no need of complicated aberration measuring and correcting devices,and can project more refined visual stimulation to human eyes so that a subject can more effectively carry out visual perception learning to improve the visual function.

A binoculus laser interference fringe visual perception study training instrument comprises a light source, an optical system, an interference fringe frequency control device, an interference fringe contrast control device, an interactive device and a computer. Two paths of the same light are obtained after coherent lights sent out by the light source pass the optical system, and are respectivelysent to the left and the right eyes of a human test subject, wherein each path of light respectively comprises two beams of coherent light and one beam of non-coherent back light, both the two beams of coherent light of each path are converged at the pupil, the produced two light points are interfered with each other, and the same interference fringes are generated at the left and the right eye grounds. The interference fringe frequency control device adjusts the converged space of the two beams of coherent light of each path at the pupil, and accordingly, the frequency of the interference fringes is adjusted; and the interference fringe contrast control device is used for adjusting the overall contrast of the interference fringe of each path. The binoculus laser interference fringe visual perception study training instrument can directly avoid the influence of human eye optical system aberration and diffraction functions, and does not need complicated aberration measurement and correction devices; and the binoculus laser interference fringe visual perception study training instrument is more approximate to the daily eye using state of human beings; and the visual function is moreeffectively improved.

A nearly 180-degree water body three-dimensional volume scattering function measuring system comprises a laser transmitter, an off-axis parabolic mirror, a scatterer, an aspherical lens group, a small-hole diaphragm, a CMOS (complementary metal oxide semiconductor) polarization sensitive camera and a computer, wherein the scatterer is positioned at the focus of the off-axis parabolic mirror. Incident laser passes through a small hole in the back face of the off-axis parabolic mirror, penetrates through the reflecting face and enters the scatterer, nearly 180-degree backward scattered light of the scatterer is reflected by the off-axis parabolic mirror and converted into parallel light beams, and the parallel light beams are collimated through the aspherical lens group and then received by the CMOS polarization sensitive camera. According to the corresponding relation between the backward scattering angle and the CMOS pixel point position, the nearly 180-degree volume scattering function of the water body on different azimuth angle scattering planes can be obtained. The measuring system provided by the invention can be used for measuring the nearly 180-degree water body three-dimensional volume scattering function.