Showing papers on "Colorimeter published in 2000"

Comparison of narrow-band reflectance spectroscopy and tristimulus colorimetry for measurements of skin and hair color in persons of different biological ancestry.

Abstract: We have used two modern computerized handheld reflectometers, the Photovolt ColorWalk colorimeter (a tristimulus colorimeter; Photovolt, UMM Electronics, Indianapolis, IN) and the DermaSpectrometer (a specialized narrow-band reflectometer; Cortex Technology, Hadsund, Denmark), to compare two methods for the objective determination of skin and hair color. These instruments both determine color by measuring the intensity of reflected light of particular wavelengths. The Photovolt ColorWalk instrument does so by shining a white light and sensing the intensity of the reflected light with a linear photodiode array. The ColorWalk results can then be expressed in terms of several standard color systems, most importantly, the Commission International d'Eclairage (CIE) Lab system, in which any color can be described by three values: L*, the lightness; a*, the amount of green or red; and b*, the amount of yellow or blue. Instead of a white light and photodiodes, the DermaSpectrometer uses two light-emitting diodes (LEDs), one green and one red, to illuminate a surface, and then it records the intensity of the reflected light. The results of these readings are expressed in terms of erythema (E) and melanin (M) indices. We measured the unexposed skin of the inner upper arm, the exposed skin of the forehead, and the hair, of 80 persons using these two instruments. Since it is important for the application of these measures in anthropology that we understand their relationship across a number of different pigmentation levels, we sampled persons from several different groups, namely, European Americans (n = 55), African Americans (n = 9), South Asians (n = 7), and East Asians (n = 9). In these subjects, there is a very high correlation between L* and the M index for the inner arm (R(2) = 0.928, P < 0.001), the forehead (R(2) = 0.822, P < 0.001), and the hair (R(2) = 0.827, P < 0.001). The relationship between a* and the E index is complex and dependent on the pigmentation level. We conclude that while both types of instruments provide accurate estimates of pigment level in skin and hair, measurements using narrow-band instruments may be less affected by the greater redness of certain body sites due to increased vascularization.

Color correction method

Abstract: PROBLEM TO BE SOLVED: To easily and surely watch a proof color by a proofer with a color of a printed matter by obtaining a difference between a printed color reproduction profile and a printing profile for an entire color space of input image data that depends upon a printing condition and correcting color measurement value data by using the obtained difference. SOLUTION: Each color patch 44 of a printed color chart Cpa is measured by a colorimeter and an original printing profile 26 which becomes an output value T0 for converting CMYK image data into color measurement value data is prepared. Next, a printer profile 36 where a RGB value of this original printing profile 26 output becomes P0 is used and a color chart Cpa' as a proof is outputted from a printer by CMYK image data of the time when the printed color chart Cpa is prepared. Then, this color chart Cpa' is color measured and a printing color reproduction profile 26', in which an output color measurement value becomes T1 when the printed color chart Cpa is reproduced, is prepared.

Apparatus for mounting an electro optical measuring device, especially a colorimeter on a monitor

Abstract: A mounting for a colorimeter enables it to make measurements of light emanating from a color monitor screen without affecting the colors produced by the screen or allowing the entry of ambient light which can affect measurements by the colorimeter (24). Pressure applied against a screen, especially an LCD color monitor, can cause changes in the color of the light emanating from the screen. The mounting apparatus is provided by a plate or pad (10) of compliant material, having an opening to which the colorimeter (24) is attached. The surface of the plate (10) is disposed against the screen (16) of the monitor (18). Since the pad (10) is compliant, it seals the colorimeter (24) from the entry of ambient light. A strap (30) can be expanded, and holds the pad (10) on the monitor (18) and against the screen (16). The strap (30) is attached to the pad (10) and is placed around the back of the monitor (18).

Colorimeter apparatus and related process

Abstract: The disclosure of this invention relates to colorimeters and a process for operating a colorimeter. The colorimeter of the disclosure is controlled by a microprocessor which evaluates a predetermined radiation absorption curve for each sample. This is to be contrasted with the prior art wherein the test on a given sample evaluates only radiation absorption concentration points which are evaluated by the microprocessor. The colorimeter gives more accurate readings as a result of the fact that an absorption curve and its parameters are evaluated for each sample. The colorimeter uses multiple LEDs as a radiation source. The microprocessor further controls other functions of the colorimeter. A separate microprocessor may be used to control these other functions. The colorimeter and process of this invention are also useful in the analysis of samples for turbidity.

Apparatus for and method of measuring body fat

Abstract: A photometer comprises a projecting mechanism irradiating a physical mass with infrared light within a wavelength region of 1.1 to 2.0 μm, a photoreceiving mechanism receiving output light from the physical mass and a spectroscope separating the light applied to the physical mass or the output light from the physical mass into its spectral components, for measuring absorbance by the physical mass at a specific wavelength. A compression mechanism can compress a measured region of the physical mass or a peripheral portion thereof, and difference absorbance calculator obtains difference absorbance from first absorbance obtained by the photometer under a state compressed by the compression mechanism with a first pressure and second absorbance obtained by the photometer under a state compressed with a second pressure lower than the first pressure or a non-compressed state. A storage part stores a relation between body fat and difference absorbance, and an operation part quantitatively determines and outputs body fat from the difference absorbance calculated by the difference absorbance calculator on the basis of the relation stored in the storage part.

Apparatus for analyzing the characteristics of ground products

Abstract: Apparatus for analyzing the characteristics of ground products, which comprises at least one vibrating chute (9) suitable for transporting particles (2) of ground product, wherein the bottom (11) of said chute (9) is transparent and means (16, 17, 18, 19) suitable for supplying to at least one colorimeter (15) the images from the bottom of the particles (2) laying on this transparent bottom (11) are arranged under the latter. This apparatus can analyze the colorimetry of the particles of ground product and also their size and purity, if desired.

Gradation characteristic data preparation system and recording medium recording gradation characteristic data preparation processing program

Abstract: PROBLEM TO BE SOLVED: To prepare gradation characteristic data by a work for a short time by measuring a density level from a common patch by plural colors regarding a patch corresponding to a lower limit value at an input level SOLUTION: A color patch necessary for measurement of a density level is printed and outputted by a printer 2 First of all, when the density level of the patch is measured by a colorimeter 3, the density level (an actual output level) is fetched in a personal computer 1 Subsequently, an output level (a predicted output level) corresponding to an input level of the measured patch is read from reference calibration data Then, if a difference between the actual output level and the predicted output level is within a specified range, the actual output level is stored as valid calibration data Interpolation is performed between the measured output levels and the density level to be actually given to the printer 2 at the time of printing is obtained

Determination of the concentrations of interferents in blood serum by use of a novel solid-state colorimeter

Abstract: The quality of the clinical-chemistry analysis of blood serum is greatly affected by interfering substances contained in the sample. At present, skilled laboratory personnel select specimens which can be processed by the analyser. Selection is performed by visual inspection of the serum colour. To reduce laboratory labour costs and risk of infections, we developed an inexpensive, simple and compact solid-state colorimeter to determine concentrations of interferents. This sensor can be integrated into modern clinical-chemistry analysers. The determination of concentrations of interferents is based on the measurement of the extinction coefficients of the serum sample at four different wavelengths. In this paper, this instrument and its performance are presented.

Information processor, profile data preparing method, display device and storage medium

Abstract: PROBLEM TO BE SOLVED: To prepare the profile of a display device from the measured result of display even in the case of display device, with which a user to perform power control or the like can not set the same condition, by simultaneously displaying a reference color and at least one measure color on the display device. SOLUTION: A colorimeter 115 can be vertically and horizontally moved and measures colors displayed on respective parts on a display picture 102a. In this case, the reference color and at least one measured color are simultaneously displayed on the display picture 102a. The reference color displayed on the display picture 102a is measured by the colorimeter 115, a measured value is stored in a memory part, the measured color displayed on the display picture 102a by the colorimeter 115 is measured and the measured value is stored in the memory part. Based on the measured reference color and measured color, the profile of a display device 102 is generated. In this case, based on the ratio of measured reference color and measured value of measured color, the profile of the display device 102 can be generated as well.

Colorimeter based on acousto-optic tunable filter

Abstract: The novel colorimeter based on acousto-optic tunable filter (AOTF) is discussed in this paper. The proposed colorimeter is based on spectrometric method of color coordinate measurements. Colorimeters of this type are known as spectrocolorimeters. The accuracy of color coordinate measurements is dependent on the accuracy of radiation spectrum measurements namely on AOTF resolution power. The results of experimental testing are provided, the structural scheme of proposed spectrocolorimeter is described. This colorimeter allows to measure the color coordinates in any colorimetric system (XYZ, Lab, Luv, etc.) and also to measure the light and color values.

System for setting conversion characteristic of image processor

Abstract: PROBLEM TO BE SOLVED: To accurately set a conversion characteristic that is used by an image processor to convert image data into data corresponding to an image forming device in response to an image forming condition of the image forming device and to employ an optional colorimeter, at setting of the characteristic. SOLUTION: A conversion characteristic setting device stores a colorimeter list, to generate a test chart corresponding to various colorimeters and basic characteristic data corresponding to various image forming conditions, allows a user to designate a colorimeter in use, image forming conditions and number of patches of a test chart on the basis of the data in the setting the conversion characteristic (S100-S150) and to allow the image forming device to generate a test chart corresponding to each designated condition (S160-S180). Furthermore, when receiving color measurement data, the setting device calculates the conversion characteristic by using the color measurement data and stores the result as conversion characteristic data used for converting image data after that (S190-S230). As a result, the setting device can set the conversion characteristic, corresponding to the image forming condition by using a desired colorimeter.

Illumination variable colorimetric method and colorimeter

Abstract: A method and apparatus allows mutual comparison of a mode of appearance of a color by the visual sense with a mode of appearance of the color from a calorimetric value from a calorimeters, and establishes a corresponding relationship between both evaluations. In the illumination variable calorimetric method and colorimeter, an illumination adjustment mechanism and an illumination measurement light receiver are disposed in a measurement optical path of an optical portion. After an illumination is adjusted to a predetermined illumination while a standard plate is placed on the surface of a sample table, standard adjustment is effected. Thereafter, measurement is started by placing a sample on the sample table, and the illumination of the sample table is varied by the light quantity adjustment mechanism so that changes in hue, saturation and lightness of a surface color of the sample and each color difference value with respect to the change of illumination of the same sample can be measured and displayed.

Method and device for reproducing color and recording medium with program executing this method recorded therein

Abstract: PROBLEM TO BE SOLVED: To obtain color reproduction method and device for an output device which do not need special colorimeter, and also reduce the time needed for colorimetry and learning. SOLUTION: A learning device fetches a Munsell color chip, etc., as an image from an input device for colorimetry, and an inverse model preparing part 201 of an input device for colroimetry prepares an inverse model for the input device for colorimetry from the color and color chip value of the image. Meanwhile, the input device for colorimetry fetches a printed matter or the like printing an electronic color chip by an output device, and corrected images are prepared by using an inverse model of the input device for colorimetry, and a color chip value measuring part 202 measures the colorimetric value of each color chip from the image. A learning part 203 prepares a sequential model of the output device and a sequential model of the input device for colorimetry, by using the colorimetric value and the color chip value. A learning part 204 prepares an inverse model of the output device. A color correcting device reads an arbitrary image, performs correction of color slurring processing, etc., by using learned results of the part 204 and reproduces colors.

Picture adjusting structure for color liquid crystal module for color television intercom

Abstract: PROBLEM TO BE SOLVED: To attain miniaturization and space saving by setting and adjusting the picture of a color liquid crystal module in a state of shielding external light while using a black box in which a colorimeter is arranged. SOLUTION: Inside a black box 1, a colorimeter 11 is fixed on a surface 14I parallel facing a screen 13 of a color liquid crystal module 12. On the other hand, the color liquid crystal module 12 can be inserted while being fitted at the central part of a lid 15 of the black box 1, positioned by a stopper 17 of the black box 1 through a hinge 16 fixed at the terminal portion of the lid 15, and arranged at a fixed distance L parallel with a light receiving part 18 of the colorimeter 11. Thus, external light is shielded and only light from the screen 13 of the color liquid crystal module 12 is made incident to the light receiving part 18 of the colorimeter 11. Thus, the setting and adjustment of luminance value or white balance chromaticity coordinate value on the screen 13 of the color liquid crystal module 12 can be performed.

Computer-aided color matching apparatus and color matching method for coating using the apparatus

Abstract: PROBLEM TO BE SOLVED: To provide a computer-aided color matching method, in which coating can be color- matched with high accuracy even with reference to the coating having a light brilliant feeling. SOLUTION: The computer-aided color matching apparatus is constituted of (A) a colorimeter. The apparatus is constituted of (B) a microscopic light-brilliant sense measuring device. The apparatus is constituted of (C) a plurality of coating mixtures, the apparatus is constituted of a computer, in which color data and microscopic light-brilliant sense data corresponding to the respective coating mixture as well as color characteristic data and microscopic light- brilliant sense data on a plurality of primary-color coatings are registered and by which a color matching calculation logic is operated. The computer-aided color matching method for the coating, having light brilliant sense performs (1) a process, in which a paint film or a reference color is measured by the colorimeter and which obtains color data on the reference color. The method performs (2) a process, in which the paint film in the reference color, is measured by the microscopic light-brilliant sense measuring device and which obtains the microscopic light brilliant feeling data on the reference color. The method performs (3) a process, in which the color data and the microscopic light-brilliant sense data on the reference color are compared with the color data and the microscopic light-brilliant sense data registered in advance and which selects a candidate coating mixture. COPYRIGHT: (C)2001,JPO

Skin-color simulation implement, skin-color simulation method and method for predicting change in skin-color

Abstract: PROBLEM TO BE SOLVED: To easily provide an implement for simulating a skin-color, method therefor and a method for predicting a change in the skin-color by using these method and implement by familiar materials, without preparing a colorimeter and many color charts. SOLUTION: By combining and overlapping each one sheet or two sheets or more of one kind or two kinds or more of transparent sheets selected among red, brown and yellow on a white body, a skin-color simulation implement is made. In this tool, a skin-color is easily simulated and a change in the skin- color is predicted by changing the combinations of the transparent sheets overlapped on the white body and increasing and decreasing the number of sheets.

Camera with light meter has colorimeter which detects color of object, and corrects exposure value accordingly

Abstract: A controller determines an exposure value based on the output of a light meter. The exposure value is corrected by the controller based on the color of the object detected by a colorimeter. The controller has a memory containing several correction values assigned to colors. A distance meter (8) is also provided. An exposure control system for a camera is also claimed.