204results about How to "Accurate measurement accuracy" patented technology

A height measuring apparatus and a bioinstrumentation apparatus with a height measuring device are provided capable of precise measurement accuracy without being affected by an examinee and being highly convenient to assemble, handle and operate. A height detector (a transceiver and a reflector or a transmitter and a receiver having a communication conformation with a laser or ultra sonic beam) has components arranged in a movable part (a head-contact arm or a movable bar) and in a stationary part (a height measurement unit (base platform) or a fixed bar) of a telescoping height measurement bar such that a communication signal route between the parts is not blocked when an examinee is standing thereon, to obtain a height measurement by detecting the distance between the movable and stationary parts.

The invention relates to a datum point positioning method based on machine vision, which belongs to the field of image processing and aims to solve the problems of poor datum point positioning accuracy and high cost of surface mounting equipment. The method comprises the following steps that a vision obtaining device is adjusted to obtain a datum point regional image; the image is preprocessed, and a threshold is set to establish a binary image; connected region labeling is performed on the binary image, so as to find out the largest connected region as a target region of a datum point; Canny edge detection is performed on an original image, so as to preliminarily determine coarse edge points; Hough transformation processing is performed on the coarse edge points, and an optimal existing circle in the image is found out; the distance between each edge point and the center of the circle is calculated; the position of a sub-pixel level of the edge point is obtained; and circular least-square fit is performed on the edge point in the position of the sub-pixel level, and then an accurate center and radius of the datum point are obtained and sent to a control system. The datum point positioning method can be widely applied to accurate positioning of the datum point.

A height measuring apparatus and a bioinstrumentation apparatus with a height measuring device are provided capable of precise measurement accuracy without being affected by an examinee and being highly convenient to assemble, handle and operate. A height detector (a transceiver and a reflector or a transmitter and a receiver having a communication conformation with a laser or ultra sonic beam) has components arranged in a movable part (a head-contact arm or a movable bar) and in a stationary part (a height measurement unit (base platform) or a fixed bar) of a telescoping height measurement bar such that a communication signal route between the parts is not blocked when an examinee is standing thereon, to obtain a height measurement by detecting the distance between the movable and stationary parts.

The invention relates to a method for adjusting a single stand reversible rolling mill, in particular to a method for adjusting housings outside the single stand reversible rolling mill, which comprises the following steps: a, determining that a housing base reaches assembly accuracy, and suspending the housings to correct positions; b, hanging a steel wire, checking vertical and transverse central lines of the rolling mill; c, connecting earphones to the vertical and transverse central lines of the rolling mill by lead wires; d, moving housings on a transmission side and an operation side towards the housing base direction on a discharge side respectively by a hydraulic jack to ensure that a bracket side of the housings is close to the lateral surface of the base on an outlet side, and moving a rail rest on an inlet side towards the outlet side; e, adjusting sizes of the housing rolling center and the transverse center of the rolling mill, and fastening a foundation bolt by 70 percentof a design torque; and f, hanging steel wires on housing windows and the rolling directions of the housings, and measuring the verticality and the horizontality of the windows and the rolling directions of the housings of the rolling mill. The method uses the steel wires and the earphones to ensure numerical reading, eliminates reading errors caused by visual errors of staff, and improves the assembly accuracy of equipment.

The invention provides an optical system for measuring eyes diopter and cornea curvature radius of a human. The system comprises a positioning monitoring light path, a projection light path, a measuring light path, a scieropia light path, and a cornea curvature measuring light path, which share an optical element. Compared with the prior art, the optical system has the technical effects that 1, a human eyes diopter measuring light path and the cornea curvature measuring light path are effectively combined in an optical system, and therefore, the human eyes diopter and cornea curvature can be accurately measured through an computer optometry unit; 2, the scieropia light path is adopted, by which the optimal cornea curvature testing state can be reached while the optic nerves of eyes to be tested are relaxed; the positioning monitoring light path enables accurate measuring precision after the distance from the eyes to be tested to the cornea curvature measuring light path is fixed; as a result, the eyes diopter and cornea curvature radius of human can be synchronously measured with one optometry unit.

The invention discloses a system for testing the power of a loudspeaker. The system comprises a computer; a plurality of test groups are connected onto the computer; each test group comprises a loudspeaker to be tested, a power tester and a power amplifier, wherein the power tester is used for detecting the loudspeaker; and the power amplifier is used for driving the loudspeaker. In the system for testing the power of the loudspeaker, a loudspeaker testing instrument is simple in structure; the number of required equipment is small; and the cost is low. The invention further provides a method for testing the power and a low-frequency parameter of the loudspeaker. The method for testing the power of the loudspeaker has the advantages of being simple to operate, accurate in low-frequency parameter measurement, rapid in operation speed and short in operation time.

The invention provides a trace dual-tube needle valve and relates to a needle valve for gluing equipment, in particular to a trace dual-tube needle valve for dual-component polyurethane. The trace dual-tube needle valve comprises a needle valve base, a seal plug, a piston A, a spring A, a baffle ring, a valve body, a piston B, an inner sleeve and the like, wherein the valve body is fixedly connected with the needle valve base; the baffle ring and the seal plug are respectively and fixedly arranged in the needle valve base by virtue of threads; a piston part of the piston A is arranged between the baffle ring and the seal plug; the piston A is used for closing or opening a glue passage A; the inner sleeve and a seal head are respectively arranged at the upper part of the valve body by virtue of threads; a washer is arranged at the upper end of the inner sleeve; external threads of an adjusting nut and an adjusting screw are sequentially connected with internal threads of the inner sleeve; a valve needle is used for closing or opening a glue passage B. The trace dual-tube needle valve is relatively accurate in measuring accuracy, applicable to trace dual-component polyurethane gluing, especially applicable to trace foaming dual-component polyurethane gluing and also applicable to other trace dual-component adhesive gluing, and the measuring accuracy of the trace dual-component polyurethane inlet glue can be easily controlled.

The invention discloses a slope measuring device and a measuring method thereof. The device comprises a bottom fixed leveling mechanism, a vertical rotary supporting mechanism and a horizontal measuring mechanism, wherein the lower end of the vertical rotary supporting mechanism is connected with the bottom fixed leveling mechanism, and the vertical rotary supporting mechanism can rotate around the bottom fixed leveling mechanism; the lower end of the vertical rotary supporting mechanism is provided with an angle measuring device which can read the rotating angle of the vertical rotary supporting mechanism; the upper end of the vertical rotary supporting mechanism is connected with the horizontal measuring mechanism, and the vertical rotary supporting mechanism can drive the horizontal measuring mechanism to rotate together; and the horizontal measuring mechanism comprises a horizontal telescopic rod, a laser range finder and a laser distance displayer, wherein the laser range finder is installed at the telescopic end of the horizontal telescopic rod. The slope measuring device has the advantages of being convenient to use and precise in measurement, saving labor cost and the like;and meanwhile, some slopes with large gradients in a severe environment and defects on upper edges and lower edges also can be accurately measured.

The invention discloses a supersonic wave wind-speed and wind-direction measuring apparatus and measuring method. The apparatus comprises an installation base, supersonic wave sensors, a temperature sensor and a wind-speed and wind-direction measuring unit arranged in the installation base. The four supersonic wave sensors are divided into two groups which are disposed on the orthogonal axises of the same horizontal plane with two facing the other two in a horizontal manner. The temperature sensor is arranged on the upper surface of the installation base. The wind-speed and wind-direction measuring unit acquires the forward transmission time and the backward transmission time of the two groups of the supersonic wave sensors as well as the voltage signal inputted by the temperature sensor to obtain the actually measured data about the initial wind-speed, wind-direction and temperature. Then, a BP neural network model is established so as to obtain the corrected wind-speed and wind-direction expression. Based on the initial wind-speed, wind-direction and temperature, the corrected wind-speed and wind-direction are obtained. According to the invention, the BP neural network model is employed to correct the wind-speed and wind-direction, which eliminates the measurement errors caused by the shadow effect and obtains more accurate wind-speed and wind-direction values.

A miniature three-dimension electric field sensor based on a flexible substrate comprises a flexible substrate, wherein a plurality of sensitive units are formed on the flexible substrate, and the flexible substrate can be folded to realize a three-dimension structure of the electric field sensor. The miniature three-dimension electric field sensor can be used for measuring the three-dimension vector of an electric field, is higher in measurement precision and has the advantages of light weight and small size. In addition, a preparation method of the three-dimension electric field sensor is simple, low in cost and favorable for mass production.

The invention relates to an air measurement type antenna device, which comprises a first signal receiving unit, a second signal receiving unit, a circuit board and a tuning unit, wherein the first signal receiving unit comprises a substrate and a microstrip patch layer, the second signal receiving unit comprises a metal piece and a grounding piece, the metal piece is connected with the circuit board through the grounding piece, the substrate is arranged on the metal piece, and the microstrip patch layer is arranged on the substrate and shares an air radiation medium layer with the metal piece; and the tuning unit comprises a fixed plate, first tuning sawteeth and a plurality of second tuning sawteeth; the fixed plate is arranged on the circuit board, the first tuning sawteeth are uniformly arranged on the metal piece, and the second tuning sawteeth are in one-to-one correspondence relation with the first tuning sawteeth. According to the invention, the first tuning sawteeth and the second tuning sawteeth are arranged in a one-to-one correspondence mode, so that the first tuning sawteeth and the second tuning sawteeth are arranged as many as possible in the limited area, thereby well improving performance parameters such as the axis ratio bandwidth, the beam bandwidth, low-elevation radiation gain and the like while realizing a miniaturized structure.

An apparatus for testing mechanical properties of a superconducting material in multiple environmental fields comprises an electronic tester unit, a multi-physical field loading control platform unit and a data collection and processing unit. The electronic tester unit comprises a base, a vacuum low-temperature box and a refrigerator, the vacuum low-temperature box comprises a view window, a transverse beam, a fixture and a sensing measuring component as well as a magnet, and the multi-physical field loading control platform unit comprises a temperature control module, a magnetic field control module, a current control module, a vacuum control module and a loading and measuring module and is used for loading and controlling the modules to operate. The apparatus is directly specific to experimental instruments and characterization for basic scientific advanced issues of functional materials and structures (for example, electromagnetic intelligent materials such as superconducting materials) in complex extreme multiple environmental fields, such as multidisciplinary and multi-field coupling issues; meanwhile, the apparatus developing at present is also a multifunctional testing appliance for mechanical properties of multi-environmental field superconducting materials, which presently has advancement and lead significance in terms of design concept and relevant functional indexes at home and abroad.

The invention discloses a device for monitoring an abnormal working state of a numerical control milling cutter and a monitoring method of the device, relates to the field of machining, and solves the problem that wear and damage of an existing cutter are hard to monitor and control in real time on line. The monitoring device comprises a measuring head, an observing cover, a collecting and emitting mechanism, a permanent magnet suction disk and a control panel, wherein the observing cover is arranged at the lower end of the measuring head; the permanent magnet suction disk is arranged at the upper end of the measuring head; the collecting and emitting mechanism is arranged between the measuring head and the permanent magnet suction disk; a positioning through hole is formed in the lower end face of the observing cover; the measuring head comprises an outer shell, a positioning mechanism and an adjustment mechanism; the positioning mechanism and the adjustment mechanism are respectively arranged in the outer shell; an eddy current vibration sensor is arranged on the adjustment mechanism. The monitoring method comprises the following steps: mounting the cutter; determining the position of the eddy current vibration sensor; starting a machine tool; constructing a signal model; performing real-time monitoring. The monitoring device and the monitoring method are used for monitoring and controlling the milling cutter in real time.

The invention discloses a quadraphonic ultrasonic heat meter. The meter comprises a pipe body, wherein the wall of the pipe body is provided with eight mounting ports, each mounting port is respectively provided with an ultrasonic transducer, four sound tracks are formed by the eight ultrasonic transducers which are opposite in pairs, the axes of every two sound tracks in the four tracks are parallel to each other, are equal in length and are symmetrically distributed at the two sides of the axis of the pipe body, and the distances between the axes of the two sound tracks and the axis of the pipe body are equal. The transducers are distributed on a section according with the velocity distribution rule of a flow field, so that the correction difficulty of measuring errors caused by a computing instrument matched with a flowmeter can be greatly reduced, and a final measuring result is more accurate; the adaptability and the stability of the ultrasonic heat meter on different incoming flows can be improved, and the installation requirements can be reduced.

The invention discloses a method and a device for detecting an oil mixing interface in sequential oil transportation, belonging to the technical field of oil-gas storage and transportation engineering. A detection device of the invention comprises a V-cone flow sensor, a temperature sensor, a data acquisition module and a computer. The V-cone flow sensor and the temperature sensor are used for obtaining pressure, pressure difference and a temperature signal of a sequential oil transportation section, and concrete position of the oil mixing interface is determined according to pressure difference of one kind of oil having certain density under certain pressure and at temperature, so that accurate cutting of the sequential oil transportation section can be implemented. In the method and thedevice of the invention, the simple V-cone flow sensor, the temperature sensor and the data acquisition module are used for properly solving the problem of mixing oil cutting in the sequential oil transportation through a program set by the computer; simultaneously, the device has the advantages of high measurement accuracy, high degree of automation, low cost, small volume and the like, and can be used for detection of oil mixing interfaces in the sequential oil transportation of industries, such as oil industry, petrochemicals industry, oil field industry and the like.

The invention relates to an object displacement measurement method based on image recognition, and the method comprises the following steps: obtaining first detection image data of an object at a first position and second detection image data of the object at a second position; carrying out the edge detection of the first and second detection image data, obtaining first edge image data corresponding to a first detection image and second edge image data corresponding to a second detection image; carrying out the positioning according to the first edge image data corresponding to the first detection image, the second edge image data corresponding to the second detection image and a centroid method, and obtaining a feature point set corresponding to the first detection image and a feature point set corresponding to the second detection image; obtaining an optimal projection relation matrix of the first and second detection images according to the feature point set corresponding to the first detection image and the feature point set corresponding to the second detection image; obtaining the relative distance of the object between the first and second positions according to a preset focal length, a preset object distance and the optimal projection relation matrix of the first and second detection images.

The invention discloses an intelligent control double-meshing automobile gear precision detection system which is mainly composed of a power source, a master control computer, a touch screen, an automatic workpiece conveying device and a double-tooth meshing instrument. The master control computer is respectively connected with the touch screen, the conveying device and the double-tooth meshing instrument. The double-tooth meshing instrument further comprises a device used for testing and building a tight meshing position between a standard gear and a workpiece to be tested through a spring type approaching device, and the device is provided with a displacement sensor and a high-precision standard test wheel. According to the intelligent control double-meshing automobile gear precision detection system, the accurate control over double-tooth measurement can be achieved by means of gear meshing between the high-precision standard test wheel and the workpiece to be tested through the master control computer and the high-precision sensor, manual interference and errors are reduced, detection accuracy is improved greatly and good applicability is achieved.

The invention discloses a rotary label, which refers to a plurality of strip-shaped transparent zones with an equal width on a non-transparent projection mask plate, wherein one non-transparent zone with an equal width is arranged between each two transparent zones; after the rotary label forms a pattern, the boundary which is a coincident part of the pattern of the rotary label and the pattern of an adjacent rotary label is called as a splicing boundary; in the rotary labels, the sum of the widths of the two transparent zones closest to the splicing boundary is equal to the width of the non-transparent zone between each two transparent zones; and each transparent zone has equal length or the length of the transparent zone closest to the splicing boundary is different from the lengths of other transparent zones. The invention also discloses a method for monitoring the photolithographic quality using the rotary label. The rotary label in the invention is suitable for a windmill-shaped cutting street, and the width of the windmill-shaped cutting street can be reduced to below 50mu m, thus being capable of reducing the ratio of the cutting street on a silicon wafer substantially.

The invention provides a detection method for ground surface settlement. The detection method comprises the steps that firstly, the position of a rear-view point is arranged outside a region to be detected; secondly, a plurality of settlement marks are arranged in the region to be detected; thirdly, an automatic tracking total station is arranged outside the region to be detected, and the data output end of the automatic tracking total station is connected with a computer center; fourthly, the automatic tracking total station is used for carrying out first-time artificial observation and aiming reading one by one; fifthly, the automatic tracking total station is started and carries out detection after being centered through a forced centering device; sixthly, the computer center carries out data processing, and a settlement value is obtained through a two-time superposition subtraction method. By means of the detection method for ground surface settlement, personnel do not need to enter water for work, measuring conditions are greatly improved, the working efficiency is improved, and engineering cost is saved.

The invention provides a manufacture method of a high temperature resistant fiber grating. The manufacture method comprises the steps that hydrogen-carrying treatment is carried out on an ordinary single-mode quartz optical fiber coated with polyimide in a high-pressure environment; the optical fiber is placed into a high-temperature oven for annealing; a grating to be written area of the optical fiber is soaked by concentrated sulfuric acid at high temperature; an ultraviolet laser is used for fiber grating writing; the grating bandwidth growth rate is between 2 pm / s and 4pm / s; after the grating spectral line bandwidth stops growing, exposure is continued for a period of time; polyimide is used to re-coat bare positions of the optical fiber; the fiber grating is placed into the oven at the temperature of 400+ / -10 DEG C for high-temperature heat treatment; and the center wavelength and the reflectivity of the grating spectral line are detected on-line. According to the invention, a sensor manufactured by the high temperature resistant fiber grating can be directly used in a working environment of 400 DEG C; and the sensor designed by the grating has the advantages of simple and direct use and accurate data.

The invention discloses a real-time monitoring system for structural micro-deformation based on a laser range finder, and particularly relates to the field of building monitoring. The system comprisesa cloud platform, wherein the input end of the cloud platform is provided with a monitoring system, the output end of the cloud platform is provided with a monitoring terminal, the connection end ofthe monitoring system is provided with a GPRS module, the monitoring system comprises a laser range finder and a level measuring instrument, and the level measuring instrument is disposed on one sideof the laser range finder. The real-time monitoring system cooperates with the laser range finder and the level measuring instrument by marking points A, B, C and D to remotely monitor the micro-deformation of the building, is convenient to install without contacting the object to be measured to avoid the phenomenon that the building is damaged, real-time monitors the measured object, considers the influence of the laser range finder on the measurement result, reduces the measurement error, makes the value obtained by the electronic level measuring instrument more accurate, improves the measurement precision accurately, and calculates the deformation amount to make the data visual.

The present invention provides an ultrasonic bone evaluation device, which performs bone evaluation by sending and receiving ultrasonic waves to the heel. The cam (1) is rotated to change the position. The profile of the rotary cam (1) has a shape with a plurality of R-curved surfaces, wherein the shape is such that the distance between the R-curved surfaces (f1)-(f8) and the center of rotation increases continuously from one side to the other in the direction of the outer circumference. shape. In addition, the rotary cam (1) is arranged to support a substantially central portion in the width direction of the foot resting platform (8) from the lower side. Therefore, the present invention provides a compact configuration that can easily and finely adjust the position of the foot resting table according to the size of the foot.

The invention discloses an automatic CCD product detecting device. The automatic CCD product detecting device comprises an electric control cabinet, rollers, supporting legs, an outer equipment cover, an X-axis component, a Y-axis component, a Z-axis component, a CCD intelligent visual system, a fixture and an R rotation shaft, wherein the CCD intelligent visual system comprises a camera, a signal transmission device and a central processing unit; the camera is used for transmitting a grabbed light signal to the central processing unit through the signal transmission device; the central processing unit is used for converting the light signal into a measurement dimension and displaying the measurement dimension through a touch screen. The automatic CCD product detecting device has the advantages that through the adoption of the CCD intelligent visual system, the measurement accuracy reaches 0.001mm, the operation is simple, the time is shortened, the measurement is of a non-contact type, the surface damage to a workpiece during the measurement is reduced, and the product quality is guaranteed. The automatic CCD product detecting device has the characteristics that scanning is automated, the resolution is high, the sensitivity is high, the structure is reasonable and the pixel grabbing position is accurate, and can be widely applied to online detection of workpiece dimensions and reduction of the source of system errors.

The invention relates to the technical field of measuring devices, especially a device and method for measuring the precision of an elevator guide rail. The device comprises a substrate, wherein one end of the substrate is fixedly provided with an infrared signal transmitter, and the other end of the substrate is fixedly provided with an L-shaped angle steel. The L-shaped angle steel comprises a horizontal plane for placing the elevator guide rail, and also comprises a vertical plane. The vertical plane is provided with an infrared signal receiver opposite to the infrared signal transmitter. A part, located at the rear side of the infrared signal transmitter, of the substrate is provided with a vertical column which is perpendicular to the substrate. The vertical column is provided with a horizontal rod which can slide up and down along the vertical column and is perpendicular to the vertical column. The horizontal rod is provided with a marker which can slide back and force along the horizontal rod and can carry out marking on the elevator guide rail. The device and method enables the measurement precision of the elevator guide rail to be higher through the additional arrangement of the infrared signal and automatic marker, can mark a warped part automatically, so as to facilitate the timely repair of the warped part.

The invention relates to a non-invasive multi-segment peripheral artery blood vessel elastic function detection method and an instrument thereof. The method is characterized in that an I-th lead electrocardiogram and multi-segment peripheral artery blood vessel photoelectric volume pulse waves are synchronously collected, the multi-segment pulse wave conduction speed (PWV) is calculated and analyzed, and the peripheral artery blood vessel elastic function is evaluated. The method comprises the following steps: A, detecting an I-th lead electrocardiogram waveform by adopting an electrocardiogram information acquisition module of an instrument; B, detecting the waveform of the peripheral multi-section pulse wave by adopting a pulse wave acquisition module of the instrument; and C, calculating and analyzing pulse wave conduction velocity (PWV) parameters by adopting a pulse wave velocity measurement module of the instrument. The detection instrument comprises an acquisition box module, anelectrocardio lead wire, a plurality of photoelectric volume pulse wave sensors and a computer (PC). The vascular elasticity function measurement with the electrocardiosignal as the pulse wave starting point and the multi-segment pulse wave as the terminal point is achieved, and the measurement accuracy and convenience are improved.

The invention belongs to the field of measuring instruments, in particular to a large mechanical force measuring machine. The novel mechanical force measuring machine mainly consists of a machine body, a frame, a weighing sensor set, a power mechanism, a pressurizing mechanism, a compression displacement multiplication mechanism and an operating instrument, wherein the power mechanism is composed of a stepper motor and a cycloidal-pin wheel decelerator and fixed above a base of the machine body; the pressurizing mechanism is composed of a pressurizing screw rod and a screw nut, and a forced direction of the pressurizing mechanism is changed by a force transmission lever; for bringing convenience to calibration work of the force measuring machine, an integrated package-type frame is composed of a frame with four upright posts and the compression displacement multiplication mechanism on a surface of a bearing table; and the displacement of the frame is increased by ten times in comparison with the deformation of a sensor per se by compressing a disc spring in the compression displacement multiplication mechanism to shrink under pressure. In an embodiment of the invention, a measurement precision value can easily reach 1 / 640,000.

The invention relates to a portable temperature measuring recorder applied to the geotechnical engineering field. In the temperature measuring recorder applied to the geotechnical engineering field, the top of a temperature probe main body (10) is connected with a temperature probe power supply signal wire (8) through a temperature probe tail sealing cover (9); the temperature probe main body (10) is provided with a temperature probe (11) at the head part and a depth sensor (24) at the middle part; an electric cable winch truck wire winch (3) is arranged inside an electric cable winch truck (1), and an electric cable winch hand wheel (2) is arranged on a center shaft (4) of the electric cable winch hand wheel of the electric cable winch truck wire winch (3). The invention effectively solves the problem that no effective measurement instrument is used for measuring the earth surface or underground temperature in the field of geotechnical engineering; and the recorder has the advantages of accurate measurement precision and high efficiency.

The invention discloses a method for testing sensitivity of a non-coherent FMCW autodyne receiver. Firstly, a power stepping value covering initial power of a minimum signal which can be received by a receiver in practical working and satisfies a precision requirement in practical working is set in a standard signal-generator; the signal-generator is arranged to be of an internal pulse modulation mode so as to generate test signals of the non-coherent FMCW autodyne receiver; test signals generated by the signal-generator are feed into the non-coherent FMCW autodyne receiver via a test antenna, and are subjected to detection in a detector in the non-coherent FMCW autodyne receiver; a direct current demodulation voltage signal Vd is output in real time to be displayed on an oscilloscope; the Vd is read out on the oscilloscope to be compared with a preset threshold magnitude of voltage VG; if the Vd=VG, a test person records the present signal source output power Prf; and the sensitivity of the non-coherent FMCW autodyne receiver is calculated according to the Prf. According to the invention, problems that the sensitivity of the autodyne receiver can not be accurately tested due to frequency temperature drift of frequency temperatures of a built-in VCO of the non-coherent FMCW autodyne receiver are solved.

The invention provides an optical system for measuring eyes diopter and cornea curvature radius of a human. The system comprises a positioning monitoring light path, a projection light path, a measuring light path, a scieropia light path, and a cornea curvature measuring light path, which share an optical element. Compared with the prior art, the optical system has the technical effects that 1, a human eyes diopter measuring light path and the cornea curvature measuring light path are effectively combined in an optical system, and therefore, the human eyes diopter and cornea curvature can be accurately measured through an computer optometry unit; 2, the scieropia light path is adopted, by which the optimal cornea curvature testing state can be reached while the optic nerves of eyes to be tested are relaxed; the positioning monitoring light path enables accurate measuring precision after the distance from the eyes to be tested to the cornea curvature measuring light path is fixed; as a result, the eyes diopter and cornea curvature radius of human can be synchronously measured with one optometry unit.

The invention discloses a vertical rolling bearing equivalent friction coefficient measuring device. The vertical rolling bearing equivalent friction coefficient measuring device comprises a machine body, a sliding seat, a mandrel, two bearing pedestals, an annular counterweight part, a rotating speed sensor and a data acquisition / processing / calculation / display device; one bearing pedestal is fixedly connected with the machine body, and the other one is fixedly connected with the sliding seat; the two bearing pedestals are provided with inner cylindrical surfaces matched with the outer rings of tested rolling bearings respectively; the two inner cylindrical surfaces are coaxial; the two ends of the mandrel are provided with shaft shoulders used for mounting the inner rings of the tested rolling bearings respectively; the mandrel is provided with the annular counterweight part; the sliding seat axially and horizontally moves along the inner cylindrical surfaces of the two bearing pedestals under external force driving; the data acquisition / processing / calculation / display device is used for collecting and processing the angular speed signal, monitored by the rotating speed sensor, ofthe mandrel, and calculating the equivalent friction torque and equivalent friction coefficient of an tested rolling bearing and a B tested rolling bearing. The measuring device has the capability ofrapidly and precisely measuring the equivalent friction torque and equivalent friction coefficient of the rolling bearing.