Abstract:
The invention relates to a method for determining the gloss of a colour standard comprising the following steps: A) experimentally determining reflection spectra R(exp) of the colour standard, comprising a first reflection spectrum and a second reflection spectrum, with an integrating sphere colour measurement instrument, wherein said first reflection spectrum is obtained at (A1) d/8°—geometry with the specular component included, and said second reflection spectrum is obtained at (A2) d/8°—geometry with the specular component excluded, and B) converting reflection spectra data of the experimentally determined reflection spectra R(exp) of the colour standard to gloss values by: B1) acquiring the difference reflection spectrum ΔR of the experimentally determined reflection spectrum R(exp) with the specular component included (A1) and the reflection spectrum R(exp) with the specular component excluded (A2), and B2) determining the gloss values corresponding to said difference reflection spectrum ΔR with the assistance of previously prepared calibration curves, representing the functional relationship between the difference reflection spectrum ΔR and the gloss values measured at one or more gloss angles.
Abstract:
The present disclosure provides methods and apparatus for testing light-emitting diodes (LEDs), for example, measuring the optical radiation of an LED. In a method, a pulse-width modulated signal is provided to the LED. One or more characteristics of the PWM signal are varied so as to provide a forward voltage, Vf, corresponding to a target junction temperature, Tj, of the LED. The optical radiation of the LED is measured when the LED obtains the target junction temperature.
Abstract:
Systems for applying pigment to a substrate has a spectrophotometer integral to the system and supplies light to the substrate and receives light from the substrate. One or more pigment dischargers integral to the system apply one or more pigments to the substrate. A spectrometer spectrally analyzes the one or more pigments applied to the substrate. The spectrometer includes an optical sensing circuit having plurality of optical sensors and one or more processing elements and a plurality of filter elements fixedly positioned with respect to at least a first group of the optical sensors. An optical implement is fixedly positioned with respect to the plurality of filter elements and has a plurality of outputs and at least one entrance. The spectrometer is fabricated in a unitary manner.
Abstract:
An optical property evaluation apparatus includes: a light conversion filter converting light emitted from an LED chip or a bare LED package, which is to be evaluated, into a different wavelength of light, and emitting a specific color of light; and an optical property measurement unit receiving the specific color of light emitted from the light conversion filter and measuring the optical properties of the received light.
Abstract:
Optical characteristic measuring systems and methods such as for determining the color or other optical characteristics of teeth are disclosed. Perimeter receiver fiber optics preferably are spaced apart from a source fiber optic and receive light from the surface of the object/tooth being measured. Light from the perimeter fiber optics pass to a variety of filters. The system utilizes the perimeter receiver fiber optics to determine information regarding the height and angle of the probe with respect to the object/tooth being measured. Under processor control, the optical characteristics measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence, gloss and/or surface texture data also may be obtained. Audio feedback may be provided to guide operator use of the system. The probe may have a removable or shielded tip for contamination prevention. A method of producing dental prostheses based on measured data also is disclosed. Measured data also may be stored and/or organized as part of a patient data base. Such methods and implements may be desirably utilized for purposes of detecting and preventing counterfeiting or the like.
Abstract:
A method for determining spectral characteristics of an object is disclosed. A probe is positioned in proximity relative to the object. The probe provides light from at least first and second light sources positioned first and second distances from a central light receiver. The first light source and the central light receiver define a first critical height from the surface below which no specularly reflected light from the first light source is received by the central light receiver, and the second light source and the central light receiver define a second critical height from the surface below which no specularly reflected light from the second light source is received by the central light receiver. The first critical height is different from the second critical height.
Abstract:
A spectroscopy system comprises a tunable semiconductor laser, such as an external cavity laser, that generates a tunable signal. A detector is provided for detecting the tunable signal after interaction with a sample. In this way, the system is able to determine the spectroscopic response of the sample by tuning the laser of the scan band and monitoring the detector's response. An integrating device, such as an integrating sphere, is interposed optically between the tunable semiconductor laser and the detector. This integrating device is used to mitigate the effects of parasitic spectral noise, such as noise that is generated by speckle or the combination of single-and multi-mode optical fibers in the transmission link between the tunable semiconductor laser and the detector.
Abstract:
An illumination device including an integrating sphere and at least one light source. The integrating sphere is hollow and houses the at least one light source in it. The light source can be manipulated between a first configuration and a second configuration. The illumination device emits a first spectrum of light when the light source is in the first configuration, and a second spectrum of light when the light source is in the second configuration.
Abstract:
A color measurement apparatus is adapted as an attachment for a personal computing system. An interface integral to the color measurement apparatus couples the color measurement apparatus to the personal computing system. A computer pointing device integral to the color measurement apparatus provides a pointer input for the personal computing system. A spectral sensing device integral to the color measurement apparatus measures light received via an input port in a plurality of spectral bands. A light source integral to the color measurement apparatus emits light external to the color measurement apparatus. The color measurement apparatus is operable in first, second and third modes of operation. In the first mode of operation, the computer pointing device provides pointer input of a user to the personal computing system. In the second mode of operation, the spectral sensing device measures light generated by a display of the personal computing system. In the third mode of operation, the light source provides light to a printed object printed by a printer coupled to the personal computing system and the spectral sensing device is adapted to receive and measure light that is returned from the printed object.
Abstract:
A process for color matching a metallic paint by taking a color measurement reading at a single angle using a regular spectrophotometer or colorimeter is provided. The preferred type of metallic pigment to be utilized in preparing the matching color can be selected by microscopic evaluation of the metallic pigment in the target metallic paint to identify its size, shape and probable composition.