Monday, April 6, 2009

Colorimeter

I had find many products about adjustable table lamp from some websites such as

Parisian Hand Painted Lamp Shade

The height of this lamp is 22 inches and the width of this lamp is 12 inches. This lamp will be a conversation piece in your home.

Ge Brand HID Xenon Headlight System Conversion Kit

GE Brand HID Xenon headlight system conversion kit2 pcs. Ballast with Connection Cables, WATER PROOF DESIGN; 2 pcs.

And you can see more from LED Recessed Lighting Fluorescent Industrial Light Color Laser Light Strobe Flash Lighting Magic Night Light Xenon Head Light LED Automotive Lighting Digital Studio Lighting Rear LED Light
Not to be confused with calorimeter.
Colorimeter
Other names
Colourimeter
Uses
Concentration measurementDisplay calibration
Inventor
Jan Szczepanik
Related items
Spectrophotometer
A colorimeter, an instrument used in colorimetry, can refer to one of several related devices.
In scientific fields the word generally refers to the device that measures the absorbance of particular wavelengths of light by a specific solution. This device, invented by Jan Szczepanik, is most commonly used to determine the concentration of a known solute in a given solution by the application of the Beer-Lambert law, which states that the concentration of a solute is proportional to the absorbance.
In digital imaging, tristimulus colorimeters, also shortened to colorimeters, are used to profile and calibrate output devices.
Contents
1 Construction
1.1 Filters
1.2 Cuvettes
1.3 Controls
1.4 Output
2 Tristimulus colorimeter
3 References
4 External links
//
Construction
The essential parts of a colorimeter are:
a light source (often an ordinary low-voltage filament lamp)
an adjustable aperture
a set of colored filters
a cuvette to hold the working solution
a detector (usually a photoresistor) to measure the transmitted light
a meter to display the output from the detector
In addition, there may be:
a voltage regulator, to protect the instrument from fluctuations in mains voltage.
a second light path, cuvette and detector. This enables comparison between the working solution and a "blank", consisting of pure solvent, to improve accuracy.
Filters
Changeable optics filters are used in the colorimeter to select the wavelength of light which the solute absorbs the most, in order to maximize accuracy. The usual wavelength range is from 400 to 700 nanometres (nm). If it is necessary to operate in the ultraviolet range (below 400 nm) then some modifications to the colorimeter are needed. In modern colorimeters the filament lamp and filters may be replaced by several light-emitting diodes of different colors.
Cuvettes
Main article: Cuvette
In a manual colorimeter the cuvettes are inserted and removed by hand. An automated colorimeter (as used in an AutoAnalyzer) is fitted with a flowcell through which solution flows continuously.
Controls

(1) Wavelength selection, (2) Printer button, (3) Concentration factor adjustment, (4) UV mode selector (Deuterium lamp), (5) Readout, (6) Sample compartment, (7) Zero control (100% T), (8) Sensitivity switch.
Output
The output from a colorimeter may be displayed by an analogue or digital meter and may be shown as transmittance (a linear scale from 0-100%) or as absorbance (a logarithmic scale from zero to infinity). The useful range of the absorbance scale is from 0-2 but it is desirable to keep within the range 0-1 because, above 1, the results become unreliable due to scattering of light.
In addition, the output may be sent to a chart recorder, data logger, or computer.
Tristimulus colorimeter

The CIE 1931 XYZ color matching functions
A tristimulus colorimeter姊抩lloquially shortened to colorimeter姊゛kes a limited number of wideband spectral energy readings (~3-7[1]) along the visible spectrum by using filtered photodetectors; e.g. silicon photodiodes.[2]
Originally, three glass filters whose transmittance spectra mimicked the CIE color matching functions (shown on the right) were employed.[3] A filter bank may be used to decompose the individual color matching functions if more accuracy is desired.[4]
A camera or colorimeter is said to be colorimetric if it satisfies the Luther condition (also called the "Maxwell-Ives criterion"),[5] reducing observer metamerism color errors, if the product of the spectral responsivity of the photoreceptor and the spectral transmittance of the filters is a linear combination of the CMFs.[6]
A colorimeter or a digital camera with a color filter array can, under certain conditions, be used as an alternative to a spectrophotometer.[7][8]
The illuminant and observer conditions should be specified when citing a measurement (e.g. D65/10).[9]
The quality of a colorimeter may be assessed using the means in CIE publication 179:2007.[10]
References
^ Colorvision Spyder brochure, pg. 2
^ Schanda, J閱s; George Eppeldauer, Georg Sauter (2007). "Tristimulus Color Measurement of Self-Luminous Sources". in J閱s Schanda. Colorimetry: Understanding the CIE System. Wiley Interscience. doi:10.1002/9780470175637.ch6. ISBN 978-0-470-04904-4.
^ Hunter, Richard Sewall (September 1942). "Photoelectric tristimulus colorimetry with three filters". JOSA 32 (9): 509538....(and so on)

LED reading lamp, LED reading light, reading lamp, LED table lamp

Item name: LED table lamp Available casing color: Silver, Dark grey, golden LED quantity: 66 pcs

You can also see some feature products :

Blue Halogen Light Tail Brake Light Floating Ball Light Cell Phone Light LED Picture Light Solar Pool Light Blood Pressure Bulb Amber Strobe Light Candle Hurricane Lamp Car Warning Light Changing LED Light Metal Floor Lamp Color Solar Light Art Table Lamps Traffic LED Light Solar Lamp Light UV C Lamp Waterproof LED Light Colored Light Bulb Halogen Flood Light LED Deck Light

1 comment:

  1. Hey thanks for sharing good information.
    Keep up tha good work.

    We provide Best colorimeter instrument in India at affordable prices and Colorimeter supplier in India, Colorimeter equipments CS-220 Precise Colorimeter, CS-200 Precise Colorimeter, CS-210 Precise Colorimeter, CS-10 Colorimeter, CS-260 Color card Reading Colorimeter and more Colorimeter buy online in India.

    ReplyDelete