398results about How to "Accurate and fast measurement" patented technology

There are provided a measuring device for a biosensor, capable of performing a simple, accurate and short-time measurement of a specific substance in a sample without being affected by physical properties of a sample, and a measuring method. In the measuring device for a biosensor in accordance with the present invention, a biosensor is used which includes: a sample supply port; an electrode system having a measurement electrode and a counter electrode; and a portion where a sample can be irradiated with light in at least part of a sample supply pathway, to detect electrical and optical variations in the sample and determine a physical factor of the sample, so that a measurement value can be corrected.

A system measures reflectance in a scene. A first optical sensor is configured to measure incident energy at a location in a scene. A second optical sensor is configured to measure reflected energy from the location in the scene. The incident energy and the reflected energy are analyzed to determine a photometric property at the location of the scene.

An autocorrelator apparatus and method for economically measuring physical properties of an object where the measurement path is at least semi-translucent to light, such as thicknesses in multilayered optical structures, group index of refraction, and distance to a surface. The apparatus includes a non-coherent light fiber interferometer and an optional coherent light fiber interferometer in association so as to share PZT fiber modulators. Thickness and boundary extent measurements can be made, for example, of solids, liquids, liquids moving along a horizontal plane, or liquids flowing down a plane.

The present invention relates to a condenser microphone assembly comprising an electro-acoustic transducer element comprising a diaphragm and a back plate, signal processing circuitry operatively connected to the transducer element so as to process signals generated by the transducer element, and a mode-setting circuitry for selectively setting the condenser microphone assembly in a test mode or an operational mode. The electro-acoustic sensitivity of the condenser microphone assembly, when operated in the test mode, is at least 40 dB lower than the corresponding electro-acoustic sensitivity of the assembly when operated in the operational mode. The present invention further relates to a method for determining a performance parameter of a signal processing circuitry mounted inside a housing of an assembled condenser microphone assembly.

The invention relates to a multichannel low-stray-light spectrograph based on an area array detector, belonging to the field of spectral analysis instruments. The spectrograph comprises an optical platform and a light signal acquisition device, and is characterized in that the area array detector serves as the optical platform; a plurality of band-rejection filters are processed and formed along the spectrum distribution direction on the window of one channel by using an imaging film-coating method; the condition of the change of the stray light received by each area of the detector is measured in real time; and by using the channel as a reference channel, the stray light of the whole spectral analysis instrument is efficiently corrected in real time. By using the spectrograph provided by the invention, the measured stray light in a full-wave band scope of a spectral analysis system is efficiently corrected. The multichannel low-stray-light spectrograph can be applied to measuring various photo-chromic parameters, such as spectrum characteristics, absorbance value, and the like of a to-be-measured sample.

The invention discloses a measurement device and a measurement method of a torsional vibration modal of a numerical control machine. The measurement device comprises a Hall sensor, a data acquisition card, a high-resolution rotary encoder, a counter, a parametric recognition module and a computer. The measurement method comprises the following steps: generating a series of sinusoidal waves with the same vibration amplitude and the same variable frequency by utilizing a numerical control device; measuring the current signal of a servo motor to obtain the drive torque of the servo motor; measuring the rotational angular velocity of a screw rod through the high-precision rotary encoder; respectively carrying out Fourier transform on a sampled angle velocity signal and the motor torque, and solving the specific value of the sampled angle velocity signal to the motor torque; solving a transfer function between all measuring points on the motor torque and the screw rod; and identifying the torsional vibration modal parameter of a motor rotor-screw rod system by utilizing a weighted least squares method to obtain inherent frequency and a modal shape of each order of torsional vibration. By the measurement device and the measurement method, the torsional vibration modal of a ball screw feeding drive mechanism of the numerical control machine can be rapidly and accurately measured, andthe torsional dynamical characteristics are analyzed; the measurement device and the measurement method provide the scientific basis for the design of the ball-screw feeding drive mechanism and the vibration control, and are applied to the measurement of the torsional vibration modal of the numerical control machine.

The invention discloses a heat-pipe performance comprehensive measurement device and method. One end of the heat-pipe(5) to be measured is mounted on a heating device(3), another end of the heat-pipe is mounted on a cooling device (7); two rotary sliding devices (2) capable of rotating and linearly sliding on the plane surface of a work platform (1) are mounted on the work platform (1), and the work platform (1) is mounted on the bracket (10) capable of rotating on the vertical plane; a temperature measurement instrument is respectively connected with the heating device (3) and the cooling device (7). The two ends of the heat-pipe are clipped on the heating device and the cooling device and the heating and cooling power is adjusted and the starting time, isothermal performance, maximum heat-transmission power and heat resistance of the heat-pipe is measured by the temperature measurement instrument; and the performance of the heat-pipe to be measured of various bending angle and length is measured by adjusting the rotary sliding device; and the performance of the heat-pipe to be measured at different inclination angle is measured by adjusting the work platform.

A system and a method for evaluating a crosstalk of a stereoscopic image display are discussed. The crosstalk evaluation system according to an embodiment includes a display element that alternately display left and right eye images each having an i-gray level and a j-gray level, where “i” and “j” are an integer, a luminance meter sensing luminances of the left and right eye images displayed on the display element, and a computer that calculates a 3D crosstalk at the i-gray level of the left eye image affected by the j-gray level of the right eye image and a 3D crosstalk at the i-gray level of the right eye image affected by the j-gray level of the left eye image based on a luminance information received from the luminance meter while changing the i-gray level and the j-gray level.

The invention discloses an assessment method for geometric errors of a five-axis tool machine, and the assessment method can be applied to a five-axis processing machine. The assessment method includes the steps that an R-test measuring tool with a probe and a standard ball is arranged on the five-axis machining machine, the sphere center of the standard ball serves as the original point of a reference coordinate system, a five-axis synchronous movement path serves as a measuring path to measure the assembly error of the five-axis tool machine, the assembly error obtained through measuring and a known mechanism parameter of the five-axis tool machine are substituted in a geometric error model, and values of 11 items of geometric errors of the five-axis tool machine are obtained through solving by using a method of least square. The assessment method has the advantages of being fast and accurate.

By making combined interferometric and polarimetric measurements on a device under test, the relative phase uncertainty in device characterizations performed with a polarimeter or polarization analyzer alone is removed. This allows determination of the group delay to within a constant offset and the chromatic dispersion of the device under test.

Circuits and methods to sense the current through a coil of an integrated switching converter, applicable to boost and to buck converters, have been achieved. The present invention uses a “replica biasing” technique to avoid a resistor for current measurement. The current through a pass device is mirrored into a replica, having a scale of n and being much smaller in size, of said pass device. The current through the replica is mirrored to another branch of the circuit and back again to achieve a fast stabilization of the current. The current through the replica is mirrored again to an output branch of the circuit, which conducts exactly a fraction 1/n of the current flowing through the pass device. The self-biasing current loop of the invention adapts quickly to the actual current level through the pass device of the switching converter. Accuracies better than 5% are achieved over a wide range of dynamic range.

The invention discloses a low-stray-light fast spectrometer and a measurement method thereof. The spectrometer includes a light signal collection mechanism and an optical platform and is characterized in that the optical platform includes a bandpass color wheel; a group of bandpass color filters and via-holes are arranged on the bandpass color wheel; and an incident light reaches a dispersive element through the bandpass color filters or the via-holes, is split and then received by an array detector. Through rotation of the bandpass color wheel, the incident light scans the bandpass color filters one by one, and the spectrometer accurately detects a sample to be detected segment by segment to correspond to a response function. When a similar sample with similar spectral characteristics is measured, the sample is accurately detected segment by segment and is subjected to full-spectrum fast detection through the via-holes, the stray light correction factor can be calculated according to the two measurement results, and the similar sample is subjected to the full-spectrum fast detection and is corrected by the stray light correction factor to achieve fast accurate detection. The method can effectively reduce the measurement stray light of the fast spectrometer and fast accurately measure the spectrum curves and related spectroradiometric parameters of the sample with similar spectral characteristics.

A door opening and closing device for a refrigerator includes a door coupled to a main body, an opening and closing unit including a drive unit for generating rotational force by means of a motor and a door rotating mechanism for opening or closing the door, a device for measuring a back electromotive force generated from the motor, a power circuit connected for supplying power to the motor, a circuit for transmitting back electromotive force of the motor to the device, a control switch for selectively connecting the motor to the circuit or the power circuit, and a control unit for connecting the control switch to the power circuit when the motor is activated, and connecting the control switch to the circuit and opening or closing the door when the motor is deactivated, wherein the control unit closes the door when a predetermined back electromotive force is input to the device.

A system for measuring chlorophyll concentration in a leaf sample includes a leaf-holding illuminator device with a main body containing a power source, a plurality of switchable light sources emitting light at different spectra (e.g., red and white light from a broadband light source), and a cap detachably secured to the main body using one or more fastening means. The leaf sample is interposed between the main body and the cap and held in place during imaging. The system includes a mobile electronic device having a camera configured to capture an image of the leaf illuminated by the plurality of switchable light sources, the mobile electronic device having wireless connectivity to a network and an application contained therein configured to transfer the images to a remote sever or computer via the network for data processing. A final chlorophyll index value is calculated based on the transferred images.

It is a rapid measurement apparatus for liquid metal and liquid alloy surface tension and it relates to metallurgy and foundry field. The power input end (1-1) is connected with output end of (11) power; the down end of (1-2) is connected with (4) and the upper end of (4-2) is connected with (4-1); the two gas-in end of (5) is separately connected with vent of (6)(6-1); the controlled end of (6) is connected with output end of (11); the controlled end of (5) is connected with output end of (11); the output end of (2) is connected with input end of (11) through (7); the output end of (3) is connected with input end of (11) through (11); the output end of (11)is connected with input end of (9); the output end of (12)is connected with input end of (11).

The invention relates to and discloses a measurement and image processing device applied to the trunk of a back. The measurement and image processing device applied to the trunk of the back mainly consists of the following eight parts: a test frame, a projection apparatus, an imaging device, a digital image recording and acquiring device, a mechanical supporting and regulating device, a computer processing module, an input device and an output device. According to the measurement and image processing device applied to the trunk of the back, which is disclosed by the invention, the precise data acquisition is carried out on an object to be tested under a non-contact condition by utilizing a grating projection measurement technique, the measurement precision is high, the measurement speed is high, and precise position location analysis can be carried out on a position needing to be tested on a computer operating platform.