188 results about "Lens thickness" patented technology

A parameter measurement device of optical system comprises a short coherent light module, a focusing lens, a collimation lens, a filtering pinhole, a splitter, a corner reflector, an one-dimension accurate mobile station, an adjustable focus telescope, a micro swivel, a focusing lens and an imaging CCD. And a relative measurement method uses optical interferometry to accurately measure the eccentricity, inclination, lens thickness and lens distances of an object optical system. The invention can improve the eccentricity measurement accuracy of lens to match higher eccentricity demand, realize the final measurement of internal distances in optical system and realize the distance of assembled optical system.

Disclosed is an optical coherence biological measurer. Parameters including corneal thicknesses, anterior chamber depths, lens thicknesses and visual axis lengths of eyes are obtained in once measurement by the aid of optical coherence measurement technology. The optical coherence biological measurer comprises a short coherence interferometry system detecting by the aid of balance, a retina splitimage focusing system, a visual axis aligning system with double fixation lamps, an optical length variable system, an eye positioning system and an auxiliary focusing system. The eye positioning system images the surface of a cornea and positions an eye, a system optical axis matches with an visual axis of the eye by the aid of the visual axis aligning system with the double fixation lamps, detecting light is respectively focused on a retina, a vitreous body and the cornea by an optical length and focus linkage device, simultaneously, optical length compensation of reference light is realized, the optical length variable system is used for realizing scanning measurement for return light signals of the retina, the vitreous body and the cornea, and the visual axis length, the vitreous bodythickness, the anterior chamber depth and the corneal thickness are calculated by the aid of output signals of a balance photoelectric detector.

The invention belongs to the technical field of optical imaging and detecting and relates to a bilateral dislocation differential confocal element parameter measuring method. The method includes the steps that dislocation differential subtracting processing is conducted on the two sides of a confocal axial characteristic data set measured by the starting points and the ending points of all various size parameters including the curvature radius, the lens thickness, the refractive rate, the focal distance and the interval, and therefore the positioning precision of the starting points and the ending points of the size parameters is improved, and the measuring precision of optical elements of the curvature radius, the lens thickness, the refractive rate, the focal distance, the interval and the like is improved. According to the bilateral dislocation differential confocal element parameter measuring method, due to the fact that two sections of data, close to the position of the full width at half maximum and very sensitive to axial displacement, of a confocal characteristic curve are used for conducting the dislocation differential subtracting processing, the position, calculated by the data sections, of the extreme point of the confocal characteristic curve is more sensitive and more accurate than the position, calculated through an existing confocal characteristic curve top fitting method, of the extreme point of the confocal characteristic curve, according to the result of the bilateral dislocation differential confocal element parameter measuring method, under the condition that the confocal element parameter system structure is not changed, the axial focusing capability, the signal-to-noise ratio and the like of the system can be obviously improved.

The present invention relates to a non-contact/non-destructive method and apparatus for measuring the thickness of an ophthalmic lens. The present invention also provides a method for inspecting or measuring the base curve of a lens.

In one aspect of the present invention, a method for manufacturing a prescription lens includes obtaining information of a prescription lens and a frame to accommodate the prescription lens, the information of the prescription lens comprising a lens power, an optical zone and a spherical front base curve, and the information of the frame comprises a frame curve; calculating the maximum lens thickness of the prescription lens at the optical zone according to the information of the prescription lens; selecting a lens according to the calculated maximum lens thickness at the optical zone, the information of the prescription lens and the frame; and processing the selected lens so as to obtain the prescription lens having an intermediate zone surrounding the optical zone and an edge zone surrounding the intermediate zone such that the thickness of the edge zone is substantially thinner than the maximum lens thickness of the optical zone.

A mounting part for mounting spectacle frame components such as lugs can be machined after confirming that a lens thickness at a mounting part-machined portion where the mounting part is machined is equal to or larger than the specified value, and can be installed the spectacle lens components on the spectacle lens with a requested strength. The device, the method for the above, a spectacle lens manufacturing method, and a spectacles manufacturing method are given. The spectacle lens (1) is fed to a lens thickness measuring device (70) by a lens feeder. The fed amount of the spectacle lens in this feeding is based on the measured results of a distance between a frame center forming a block center by a lens holder in an edging for manufacturing the spectacle lens (1) from a raw material lens and the edge face of the spectacle lens (1) where the mounting part is to be machined. The thickness of the lens at the mounting part-machined portion can be accurately measured by the measuring device (70) even if an error produced in the edging is included in the distance.

An image pickup lens system has a four-lens configuration which forms an image on a solid-state image pickup device. The image pickup lens system includes, from an object side, a positive first lens, an aperture stop, a positive second lens, a negative third lens whose concave surface is faced toward an image surface side, and a positive fourth lens in the order from an object side. A ratio of an axial lens thickness of the third lens to a focal length of the whole system is optimally set. Therefore, an exit pupil position can be kept far away from the image surface while the image pickup lens system has good optical performance and a compact size.

An eyeglass lens processing apparatus includes: a lens rotation unit rotating a lens; a processing tool rotation unit processing the lens; an axis-to-axis distance changing unit for changing an axis-to-axis distance between the chuck shaft and the processing tool rotation shaft; a lens surface configuration acquiring unit which acquires a front surface curve configuration and a rear surface curve configuration of the lens; a lens outer diameter acquiring unit which acquires an outer diameter of a lens; a calculation unit which calculates a thickness of the lens and calculates a cutting depth of the lens, so that torque applied onto the chuck shaft in rough processing becomes substantially constant, based on the calculated lens thickness and a processing distance from the rotation center of the lens; and a control unit which controls the axis-to-axis distance changing unit in accordance with the calculated cutting depth and for rough processing the lens.

Multifocal lenses are defined by nonconical aspheric optical surfaces. Various alternative surface shapes provide a central distance vision region surrounded by an optical step. The optical step has repidly increasing power in the radial direction which creates an induced aperture through which the cortical elements of the vision system are induced to concentrate. The induced aperture results in increased clarity in distance vision. Nonconical aspheric optical surfaces are defined to produce the desired optical power distributions. These surface functions are also provided in form of polynomial series for simplicity of use in computer driven lathes for shaping contact lenses. To allow increased manipulation of the defining functions additional elements such as conic terms are added. To improve near vision correction in some configurations, an annular near vision region extends radially outward from the optical step. To improve low light distance vision, power is reduced in the lens region outside the mesopic pupillary dimension. In alternative embodiments, the distance vision region and optical step are formed by cyclic functions. These have benefits in ease of manipulation to fit various specific user geometry requirements. In some configurations, an extended near vision region is used outside the optical step to improve near vision correction. The invention includes contact lenses, scleral lenses, intraocular lenses, and lenses impressed or surgically shaped within the corneal tissue as well as methods of designing and fitting these lenses. Although nominally positive power lenses are also within the present invention, negative lenses gain particular benefit due to decreased lens thickness at the lens perimeter and consequent reduced spherical aberration.

The invention discloses an eye ground retina OCT image correction method. The method comprises the steps that scanning beams scan an anterior segment and a posterior segment, and meanwhile a human anterior segment OCT image and an eye ground retina OCT image are obtained, wherein the human anterior segment OCT image contains a corneal OCT image, a crystalline lens anterior surface OCT image and a crystalline lens posterior surface OCT image, and the human anterior segment OCT image and the eye ground retina OCT image are processed by a computer without correction; the OCT images are corrected and restored to images with a true form to obtain the corneal anterior surface curvature radius, the corneal posterior surface curvature radius, the crystalline lens anterior surface curvature radius, the crystalline lens posterior surface curvature radius, the corneal thickness, the anterior chamber depth and the crystalline lens thickness; a rendezvous point (O45) of center lines of the scanning beams which are refracted by the posterior surface of a crystalline lens is determined, and the circle center of the sector scanning region and the scanning angle (uO45) are calculated; the uncorrected eye ground retina OCT image is restored to an image with a true form, and finally a true sectional image of an eye ground retina is obtained through restoration and the curvature of the eye ground retina is measured according to a measured anterior segment OCT image and a measured posterior segment OCT image.

A wide-angle photographic lens system enabling correction of distortion composed of three lenses, in which a first lens, an iris, a second lens and a third lens sequentially arranged along an optical axis from an object, wherein the first lens has weak refractivity, the second lens has strong positive refractivity, and the third lens has negative refractivity, wherein the lens system satisfies relations, |f1/f|>2.8, f2/f<1, and te/tc<0.4, wherein f1 is a focal length of the first lens, f is a total focal length of all the lenses, f2 is a focal length of the second lens, te is a lens thickness on an effective diameter of a rear surface of the second lens, and tc is a center thickness of the second lens.

A foldable lens comprises an outer refractive surface portion comprising a first plurality of convexly curved refractive profile regions having positive optical power to converge light energy with refraction toward a focus on the retina. The convexly curved refractive profile regions of the outer region may correspond to at least about a quarter of the refractive power of the lens, such that the lens thickness is decreased substantially and the folded lens can fit through a small incision. The outer refractive surface portion focuses light with refraction, in focus images viewed through the outer portion of the lens can appear sharp to the patient. The outer refractive surface portion also comprises a second plurality of concavely curved refractive profile regions having negative optical power disposed between the first plurality, so as to diverge the light energy substantially away from the focus on the retina, such that visual artifacts are inhibited.

An imaging optical system a high quality image may be implemented by determining the optimum design conditions for suppressing the generation of ghost while holding uniform and sufficient light using a simulation method. In the imaging optical system having a slit, the requirements for removing the stray light are the inclination of a lens arrangement direction, the slit width, the lens pitch, the view angle, and the height of the light-shielding wall. The slit location, the lens thickness, and the lens row width do not affect the stray light removal, but affect the brightness. In the imaging optical system having no slit, the essential requirements for removing the stray light are the height of the light-shielding wall and the lens pitch. The lens thickness and the lens row width do not affect the stray light removal, but affect the brightness.

A zone phase correcting lens wherein a change in the third-order spherical aberration or the like is small in the case of a change in temperature and an optical head device having the zone phase correcting lens used as an objective lens. A minus sign is appended to the height measurement of a step formed so as to make the lens thickness in the optical axis thinner toward the outer region and a plus sign is appended to a step formed so as to make the lens thickness thicker toward the outer region. Supposing that D is an absolute value of the sum of the height measurements of the steps having the minus sign on the first surface and the second surface and E is an absolute value of the sum of the height measurements of the steps having the plus sign on the first surface and the second surface, a wavelength λ₁ and a refractive index N₁ of the lens for a first laser beam satisfy the following conditions:

10×λ₁<{D×(N₁−1)}<30×λ₁

2×E<D.

A lens element is provided that includes a housing defining a center bore and an optical axis, and a light transmissive cover coupled to the housing. A first elastic solid lens is disposed within the housing adjacent the light transmissive cover, and is characterized by a first thickness and a first durometer hardness. A second elastic solid lens is disposed in the housing adjacent to and substantially conforming to the first elastic solid lens, and is characterized by a second thickness and a second durometer hardness. The second lens thickness is less than the first lens thickness, and the second durometer hardness is greater than the first durometer hardness. In one embodiment, the first durometer hardness is less than OO60 as measured by the Shore method, and the second durometer hardness is in the range of A20 to A60 as measured by the Shore method.

A wide-angle photographic lens system enabling correction of distortion composed of four lenses, in which a first lens, an iris, a second lens, a third lens and a fourth lens sequentially arranged along an optical axis from an object, wherein the first lens has weak refractivity, the second lens has positive refractivity, the third lens has strong positive refractivity, and the fourth lens has negative refractivity, wherein the lens system satisfies relations, |f1/f|>4, f3/f<1.5, and te/tc<0.5, wherein f1 is a focal length of the first lens, f is a total focal length of all the lenses, f3 is a focal length of the third lens, to is a lens thickness on an effective diameter of a rear surface of the third lens, and tc is a center thickness of the third lens.

The invention discloses an automatic focal power packing machine for a lens. The machine is based on automatic control technology and is manufactured by organically combining a plurality of instruments and devices; when the machine is used, a control system controls a lens conveying line for conveying the lens, controls a lens diameter detection device, a lens thickness detection device and a focal power detection device which are arranged along the lens conveying line to detect a lens to be detected, and acquires data of a detection result; meanwhile, the control system controls a paper bag conveying line for conveying a paper bag and controls a printer arranged on the paper bag conveying line to perform lens parameter printing on the paper bag; and finally, the control system controls the two conveying lines to convey the lens and the paper bag to specified positions respectively and controls a lens pushing cylinder and a paper bag opening device to bag the lens. As the measuring and the packing of the lens are automatically completed, the production efficiency can be greatly improved; and the workload of workers and the measurement error of products are reduced.