46results 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 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.

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.

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.

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.