A gadget for retroreflected signal measurement is disclosed. The gadget for measuring the retroreflected signal includes a partitioning wall; a portable terminal receiving portion disposed on one surface of the partitioning wall; a biosensor receiving portion disposed on the other surface of the partitioning wall and constructed to receive a biosensor therein; a light exit channel defined in the partitioning wall and at one side thereof; and a light-receiving channel adjacent to the light exit channel and defined in the partitioning wall, wherein light passes through the light exit channel and then is reflected from the biosensor, and then is incident into the light-receiving channel.

This invention relates to an apparatus for retro-reflection measurement. By using the one or more sampling devices each consists of a holed mirror and an circular aperture, and corresponding one or more measuring devices, it realize the retro-reflection measurement in one or more observation angles at one time. By flexibly selecting the size of the circular apertures and holed mirrors, it can accurately adjust the measuring annular bands and corresponding observation angles. Without any other intermediate devices, it can realize complete annular band of light measurement which ensures the measurement accuracy. At the same time, filters and monitor device can be set flexibly to realize various measurement functions. It has the advantages of speed measurement, high accuracy, small volume, wide application, comprehensive functions, and can be widely applied in laboratory, industrial production line and field measurement etc.

Disclosed is a retroreflector-based sensor system for optical characterization of a sample, having a transmitter for irradiating the sample, a retroflector positioned behind the sample, the transmitter, the sample, and the retroreflector being positioned such that radiation reflected back from the retroreflector is again incident on the sample and is reflected back from the latter in the direction towards the transmitter, and a receiver which is positioned in the receiving beam path such that it detects radiation reflected back from the retroreflector, incident again on the sample and reflected back from the latter, in the direction towards the transmitter.

A retroreflectivity measurement system comprises a light source arranged to project light across a traffic lane during a measurement run, the light being limited to a particular portion of the visible light spectrum. A camera is selectively sensitive to this light to provide first filtered images and separately selectively sensitive to light at a portion of the spectrum not including the particular portion to provide second filtered images. A controller obtains sequences of first and second filtered images during the measurement run, and identifies within the sequences of images an illuminated road marking; determines a first intensity of the marking from a first filtered image, and a further intensity of the marking from the second filtered images; estimates an ambient intensity of the marking, by applying a scaling factor to the further intensity; and determines a retroreflectivity of the marking as a function of the first and estimated ambient intensities.

A system, method and assembly for performing traffic sign inspections is provided. In one embodiment, the assembly includes a first plurality of sheetings that each have a combination of retroreflectivity and color that is different from the combination of retroreflectivity and color of each of the other first plurality of sheetings; a first clamp and second clamp for clamping one of said first plurality of sheetings to a traffic sign; a first handheld light source; and a first enclosure for removably housing the first plurality of sheetings, said first and second clamps, and said first handheld light source. The assembly may further include a second enclosure for removably housing a second plurality of sheetings that each has a combination of retroreflectivity and color that is different from the combination of retroreflectivity and color of each of the other second plurality of sheetings.

A method of airfield markings assessment and scheduling predictive maintenance periodically measures characteristics of individual portions of an airport's runways, and identifies the measured locations. The periodic individual portion measurements the airfield's runways and such measurements at similar airfields' runways are used to determine projections of how long the runway's individual marking portions will separately comply with FAA's marking requirements and the results used to schedule a predictive maintenance program which periodically removes and replaces less than all of the runway's markings.

An optical probe for a bio-sensor selectively conjugated to a target analyte and configured to retro-reflect incident light thereto is disclosed. The optical probe for the bio-sensor includes: a transparent core particle; a total-reflection inducing layer covering a portion of a surface of the core particle, the inducing layer is made of a material having a refractive index lower than a refractive index of the core; a modifying layer formed on the total-reflection inducing layer; and an analyte-sensing substance bound to the modifying layer, the sensing substance is selectively conjugated to the target analyte. This optical probe may serve as an excellent optical probe for both a non-spectral light source and a spectral light source.

A method for detecting a characteristic of a forming material and a three-dimensional printing apparatus are provided. The three-dimensional printing apparatus includes a tank filled with a liquid forming material, and the method includes the following. The tank is controlled to swing to cause a wave motion on a liquid surface of the liquid forming material. The wave motion of the liquid forming material is detected to obtain detection waveform information. The detection waveform information and sample waveform information are compared with each other to obtain a characteristic comparison result. A predefined operation is executed according to the characteristic comparison result.

A growth-rate measuring apparatus has a refractometer to irradiate light of a plurality of different wavelengths to a surface of a substrate to measure a reflectivity of the surface of the substrate per different wavelengths, a fitter to fit a reflectivity calculated by a model function, the model function being obtained in advance, to a measured value of the reflectivity, for at least one layer of thin films laminated one by one on the substrate, with at least one of a refractive index and a growth rate as a fitting parameter, a parameter extractor to extract sets of fitting parameters for each wavelength in the different wavelengths, respectively, for which an error between the calculated reflectivity and the measured value of the reflectivity is minimum, and a parameter selector to select an optimum set of values of the fitting parameter, among the fitting parameters extracted for the different wavelengths.

The method of the invention comprises: obtaining a sequence of at least two images, with different levels of illumination; extracting the region containing the sign in the image; calculating the luminance values of the signs; and obtaining the difference in luminance of the sign corresponding to the two levels of illumination. The value obtained is the luminance of the sign (11) corresponding to an illumination equal to the difference between the illuminations, or additional illumination. This result is based on the additive property of luminance, according to which the luminance of a sign is the sum of the luminance produced by each source of illumination. A basic illumination device (5), an additional illumination device (7), at least one camera for taking images, and image recording, positioning and synchronism systems are required to implement the method.