A method of measuring the color of a surface may include a device positioned above the surface. The device may include an optical sensor and a display screen. The optical sensor measures visible light level reflected from the surface in a plurality of spectral channels. A plurality of patterns are sequentially displayed on the display screen. The optical sensor is used to measure light reflected by the surface during display of each pattern. A value is determined for the distance from the optical sensor to the illuminated region for a first local maximum of intensity of the measured light reflected by the surface. A location in a color space corresponding to a color of the surface or a reflectance spectrum of the surface is determined based on the visible light level in each spectral channel for the value of the distance corresponding to the first local maximum.

Gloss of a surface having a concave-convex structure is measured, and R/V, which is a ratio of a diffuse specular reflection intensity R to a sum total V of diffuse reflection intensities (in formula, the diffuse specular reflection intensity R represents a diffuse reflection intensity measured at an aperture angle of 1 degree by a variable-angle photometer in a diffuse specular reflection direction when visible light is radiated, at an angle of 45 degrees from a normal line, to the surface having the concave-convex structure of the anti-glare film, and the sum total V of diffuse reflection intensities represents a sum total of diffuse reflection intensities measured at an aperture angle of 1 degree by a variable-angle photometer for every 1 degree from −45 degrees up to 45 degrees, including 0 degrees, with respect to the diffuse specular reflection direction when visible light is radiated, at an angle of 45 degrees from a normal line, to the surface having the concave-convex structure of the anti-glare film), is evaluated to manufacture an anti-glare film. The above-described method enables an anti-glare film having high anti-glare properties and high contrast to be manufactured at high productivity.

A housing includes a first opening and a second opening, and encloses a light-emitting element and a first light receiving unit. The first opening is provided in a first light guide path, and is arranged so that light output from the light-emitting element travels toward a target surface. The second opening is provided in a second light guide path arranged between the target surface and the first light receiving unit. The first opening is an exit opening of a through-hole provided penetrating through the housing, and a shape of the through-hole is a shape in which diffracted light of the +1st order and higher orders and diffracted light of the −1st order and higher orders produced at the target surface to be irradiated are not incident on the first light receiving unit.

A medium identification device identifies a type of a recording medium used for image formation. The medium identification device includes: a two-dimensional image sensor that captures an image of the recording medium; and an identifying unit that obtains a glossiness evaluation value indicating glossiness of the recording medium, a surface roughness evaluation value indicating surface roughness of the recording medium, and a coloring evaluation value indicating coloring of the recording medium, using image data of a specular reflection region reflecting specular reflection light from the recording medium and image data of a diffused reflection region reflecting diffused reflection light from the recording medium, the regions being in the image of the recording medium, and identifies the type of the recording medium by combining determination using the glossiness evaluation value, determination using the surface roughness evaluation value, and determination using the coloring evaluation value.

A method for sorting products and sorting apparatus with a flow of granular products moving in an inspection zone, in which a light beam is moved over the product flow to generate a reflected stream of light. At least one detector unit is provided to detect light reflected by the products to generate detection signals. This detector unit cooperates with a control unit to sort the products by these detection signals. The detector unit contains at least two sensors that are provided one after the other in the reflected stream of light so that a sensor is placed upstream of a downstream sensor. Each sensor detects a different part of the reflected stream of light.

Systems for measuring optical properties of a specimen are disclosed. The systems are configured to sample signals related to the measurement of the properties of a specimen, and perform software-based coherent detection of the signals to generate resulting measurements are based on the signals acquired at substantially the same time instance. This facilitates the displaying or generating of the desired measurements in real time. In one configuration, the system is configured to direct a modulated light signal at a selected wavelength incident upon a specimen. In another configuration, the system is configured to direct a combined light signal, derived from a plurality of light signals at different wavelengths and modulated with different frequencies, incident upon a specimen. In yet another configuration, the system is configured to direct a plurality of light signals modulated with different frequencies incident upon different regions of a specimen.

3D shape reconstruction of glossy objects includes separation of diffuse and specular components of reflection from the object. Multiple layers of E-glass arranged in spaced-apart relation with each other, together with a camera for capturing images of reflected light. A first polarizer is positioned to polarize incident light before it reaches the object and a second polarizer is configured as an analyzer to analyze the light reflected from the object. The degree of polarization is varied. Images are captured of a structured light pattern as reflected in both diffuse and specular reflection the surface of the glossy object. A diffuse component of reflection is extracted by using the captured images of the deformed patterns, and a specular component of reflection is extracted by using the diffuse component of reflection and the captured images under polarized illumination. Depth of the surface of the object is estimated by fusing the diffuse component and the specular component.

A combination surface type sensor may include a housing including a first receptacle, a second receptacle, a third receptacle, and a fourth receptacle, a first surface type detector disposed within the first receptacle, a second surface type detector disposed within the fourth receptacle, an emitter disposed within the second receptacle, and a drop-off detector disposed within the third receptacle.

A measurement arrangement for measuring diffusely reflected light and specularly includes a measurement light source for generating measurement light, an optical receiver for receiving measurement light, and a first mirror for reflecting the measurement light emerging from the measurement light source. The measurement arrangement additionally comprises a second mirror for reflecting diffusely reflected measurement light to the optical receiver. A settable third mirror is also provided, which in a first position is aligned for directing the measurement light that was directed onto a sample by the first mirror and specularly reflected by the sample to the optical receiver. The third mirror in a second position releases a beam path between the second mirror and the optical receiver, so that the measurement light directed onto the sample by the first mirror and diffusely reflected by the sample to the second mirror is directed to the optical receiver by the second mirror.

The present invention is intended to make it easier to perform positioning of a detection device when detecting surface characteristics of a sensing object. The invention includes a detection device, a processing part, a guidance information generation part and an informing part. The detection device detects reflection light from a sensing object by irradiating light onto the sensing object. The processing part calculates surface characteristics of the sensing object by processing data from the detection device. The guidance information generation part generates information about a distance and/or an attitude of the detection device relative to the sensing object. The informing part informs the information about the distance and/or the attitude generated by the guidance information generation part.