145 results about "Radius of curvature" patented technology

The invention discloses a method for detecting the curvature radius of an optical spherical surface, relating to a method for measuring the curvature radius of the optical spherical surface and aiming to solve the problems of errors existing in the conventional method for measuring the curvature radius of the optical spherical surface and difficulty in accurately realizing measurement of a spherical mirror with a large curvature radius by adopting the conventional measuring method. The method comprises the following steps of: adjusting relative positions of a target sphere and an interferometer and judging whether the curvature center of the target sphere is overlaid with the front focal point of the emergent waves of the interferometer or not; if so, measuring the curvature center coordinate of the target sphere by using a laser tracking instrument, wherein the curvature center coordinate of the target sphere is the coordinate of the front focal point of the emergent waves of the interferometer; if not, continually adjusting the relative positions of the target sphere and the interferometer until the spherical mirror to be detected reaches a zero stripe interference state; measuring the position coordinates of a plurality of points on the spherical mirror to be detected by using the laser tracking instrument; and averaging, counting and operating a plurality of values to obtain the curvature radius of the optical spherical mirror to be detected. The method is suitable for the technical field of optical measurement.

The invention relates to a detecting device for measuring the difference of relative radius of curvature between sub-lenses of a sphere surface spliced telescope. The device comprises a confocal adjustment system and a spherometer, wherein the confocal adjustment system comprises a laser source arranged on a mounting plate, a pin hole, two collimating lenses, a dispersion prism, a Shack-Hartmann wave-front sensor, a planar reflector, a micrometric displacement translational platform, a controller of the micrometric displacement translational platform and a computer; after passing through the pin hole and a first collimating lens, light beam emitted by the laser source is emitted out through a second collimating lens after reflection through the dispersion prism; the Shack-Hartmann wave-front sensor is arranged on the other side of the dispersion prism, which is coaxial with the reflecting light path of the dispersion prism; the planar reflector is arranged on the optical axis outside the focal surface of the second collimating lens; and the reflecting light path of the planar reflector is provided with the micrometric displacement translational platform carrying the sub-lens to be measured. The device does not require a standard reference lens, is independent from testing environment, and has high measurement accuracy and high efficiency.

A method and test apparatus determines a volume of a droplet of liquid. The test apparatus deposits a drop of liquid to be measured on a surface that provides a known contact angle with the liquid under the deposition conditions used, thereby establishing one of: (i) an advancing, (ii) a receding, and (iii) an intermediate contact angle. The test apparatus images the drop. The test apparatus measures a dimension of height or diameter of the drop. In one embodiment, the test apparatus calculates a volume of the drop of liquid from the relationship of the contact angle to one or more parameters selected from the maximum height, the diameter of the contact patch, the radius of curvature, or the cross sectional area of the drop.

The invention relates to the technical field of measurement methods, in particular to a curvature radius measuring method. The curvature radius measuring method is not influenced by factory environments such as a vibration environment and the like and belongs to non-contact measurement; and by the method, a surface to be detected cannot be damaged, the requirements of quick large-scale on-site measurement can be met, and the surface curvature radiuses of polished and unpolished parts can be measured at the same time. The curvature radius measuring method provided by the invention comprises the following steps of: cutting a sphere by using two planes between which the distance is (D), wherein the (D) is less than the diameter of the sphere, and two circles are formed by intersecting lines between the two planes and the surface of the sphere; and obtaining the sum of the radiuses of the two circles by a non-contact measurement method, wherein the curvature radius of the surface to be detected is shown as a formula in the specification.

A controlled radius of curvature mirror assembly comprising: a distortable mirror having a reflective surface and a rear surface; and in descending order from the rear surface; a counter-distortion plate; a flow diverter having a flow diverter aperture at the center thereof; a flow return plate having a flow return aperture at the center thereof; a thermal isolation plate having a thermal isolation plate aperture at the center thereof and a flexible heater having a rear surface and a flexible heater aperture at the center thereof; a double walled tube defining a coolant feed chamber and a coolant return chamber; said coolant feed chamber extending to and through the flow diverter aperture and terminating at the counter-distortion plate and the coolant return chamber extending to and through the thermal isolation backplate and terminating at the flow diverter; and a coolant feed and a coolant return exit at the rear of said flexible heater.

The invention relates to a method for measuring the radius of curvature of a spherical surface. According to the method, a reference substance (2) of which the size is a is coaxial with a microscope objective (3), and the distance between the reference substance (2) and the vertex of a measured spherical surface (4) is L, wherein L can be changed independently in the axial direction; the reference substance (2) is reflected by the measured spherical surface on an object carrying platform (5) to form an image (6) of which the size is b, the image (6) is subjected to microscopic amplification by a microscope system to form an image (7) of which the size is c, and the image (7) is acquired by a charge coupled device (CCD) camera arranged on a microscope ocular lens (1) and is stored in a computer. The radius of curvature r of the measured spherical surface can be expressed by a function which contains the parameters of a, c and L, wherein a and L are measured directly, and c is measured by utilizing computer software, so that the radius of curvature of the measured spherical surface r can be measured. The reference substances are annular cross hairs or annular illuminants preferably, and can be equipped with multiple groups according to requirements. Preferably, the magnifying power of the microscope objective is continuously adjustable.

The invention provides a method for measuring curvature radiuses of different points on a spherical surface by using a phase measurement deflection technology. According to the method, an LCD displayis adopted to display sine stripes, the stripes are reflected by a spherical element to be measured and then captured by a pinhole camera, and in known pinhole coordinates of a CCD camera, light rayswhich correspond to CCD camera pixels and pass through pinholes are reflected by a reference plane and the spherical element to be measured to intersect at the coordinates on the LCD display in the Z-direction position of the reference plane; parameters such as the spatial position of the spherical surface and the coordinate of the measured surface are obtained by using minimum angle condition optimization and an iterative method, and then the curvature radius distribution of the spherical surface is obtained by using a differential geometry method. According to the method, the curvature radius of each point on the spherical surface can be rapidly and accurately measured.

The invention relates to a system and a method for accurately positioning a center of a curvature radius of an off-axis spherical reflector. The system comprises a high-precision flat plate, a rotating shaft, a reticle with a cross wire and a high-precision microscope, wherein an inner hole is arranged on the high-precision flat plate, the rotating shaft is arranged inside the inner hole of the high-precision flat plate, the reticle with the cross wire is vertically arranged on the rotating shaft and can rotate freely inside the inner hole of the high-precision flat plate along with the rotating shaft, and the high-precision microscope and the reticle with the cross wire are arranged on the same optical axis. The system and the method for accurately positioning the center of the curvature radius of the off-axis spherical reflector is high in positioning precision, easy to adjust and convenient to operate.

The invention provides a method for acquiring human corneal topography by using a trigonometric function, recursion and other mathematical methods. According to the method, concentric rings need to bedisplayed by an LCD display device, a cornea performs reflection and a camera performs receiving; and the x, y coordinates Xs, Ys of pixels on the LCD display device, the x, y coordinates Xc, Yc of the CCD, the x, y coordinates Xm, Ym of the human cornea as well as a distance from the midpoint of the display device and the pinhole of the camera to the vertex of the human cornea are known. According to a geometrical relationship of all the elements and assumption of forming of the cornea by a plurality of adjacent arcs, a curvature radius and a z coordinate of a first circular ring are obtained and then recursion is conducted in sequence to calculate the curvature radius and the z coordinate of the whole cornea, so that the terrain of the human cornea is obtained. According to the method,the accuracy of the human corneal topography is improved.

The invention discloses a quantitative analysis method of tunnel vault lining void, which comprises the following steps of: arranging a longitudinal geological radar measuring line on a tunnel centerline so as to determine two-dimensional data of a longitudinal section of a tunnel vault lining void area, and calculating the volume of the void area by utilizing a lining void quantitative analysisformula, wherein V is the volume of the void area, R is the curvature radius of the vault, a and b are the lengths of vertical line segments from the midpoints of the vaults at the head end and the tail end of the void area to the bottom surface of the void area respectively, and L is the longitudinal length of the void area. By the adoption of the technical scheme, the quantitative analysis method for tunnel vault lining void can determine quantitative information of tunnel vault lining void, including three-dimensional model space attributes such as the space form, position distribution andsize of quality defects.

The invention relates to a method for controlling the conformity of a profile of a section of a curved surface of a turbomachine element, comprising the following step: —(100) acquiring coordinates of a plurality of measurement points of the section in a frame of reference defined for said section; characterised in that the method comprises the following steps: —(200) calculating, based on the coordinates of these measurement points, the radius of curvature of the section at each of these points, in order to obtain a measured evolution curve of the radius of curvature according to the position of the measurement points along said section; —(300) comparing the measured evolution curve of the radius of curvature, obtained in the preceding step, with a theoretical evolution curve of the radius of curvature of the predetermined section; —(400) evaluating the conformity of the section based on the comparison carried out in the preceding step.

The invention discloses a biggest superelevation calculation method for a debris flow curve and application and belongs to the technical field of debris flow preventing and treating projects. The biggest superelevation calculation method for the debris flow curve is characterized by comprising the following steps that a, the average flow speed V of debris flow at the debris flow occurring place is acquired; b, the channel width B of the debris flow at the debris flow occurring place is measured on site; c, the center curvature radius R of the debris flow curve is measured on site; d, the yielding stress tau of the debris flow is measured and calculated; e, the density Rho of the debris flow is measured and calculated; and f, a biggest superelevation value delta H of the debris flow curve is acquired by means of calculation of formula 1. The biggest superelevation calculation method for the debris flow curve is applicable to actual large-scale calculation on the field, the influences of the nature of the debris flow on the superelevation are considered, superelevation may be produced by the debris flow with different yielding stresses at the same curve position under different speed conditions can be accurately calculated, better theoretical data reference is provided for defensive measures of the debris flow, and higher disaster preventing applicability and universality are achieved for debris flow disaster reducing.

The present invention discloses a system and method for nondestructively measuring the refractive index and the central thickness of a lens. The system comprises a radius measurement module arranged for measuring the curvature radius of the first surface of the lens; a focus measurement module arranged for measuring the best focus distance of the first surface of the lens; and a calculation module arranged for performing the first or the second calculation process according to the lensmaker's formula. Wherein, when the central thickness is given, the calculation module performs the first calculation process according to the curvature radius, the best focus distance and the central thickness to calculate the refractive index. On the contrary, when the refractive index is given, the calculation module performs the second calculation process according to the curvature radius, the best focus distance and the refractive index to calculate the central thickness.

In a magneto optical device is which a laser beam is shone in operation through a coil (5), the coil holder (6) comprises a concavely curved exit surface with a radius of curvature R lying between 0.5 D and 15 D (0.5 D≦R≦15 D) where D is the diameter of the concavely shaped exit surface.