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If the instrument is designed to measure the spectrum on an absolute scale rather than a relative one, then it is typically called a spectrophotometer. The majority of spectrophotometers are used in spectral regions near the visible spectrum. A spectrometer that is calibrated for measurement of the incident optical power is called a ...
Developed by Bausch & Lomb and launched in 1953, the Spectronic 20 was the first low-cost spectrophotometer. [5] It rapidly became an industry standard [7] due to its low cost, durability and ease of use, [8] and has been referred to as an "iconic lab spectrophotometer". [9] Approximately 600,000 units were sold over its nearly 60 year ...
GFAA spectrometry instruments have the following basic features: 1. a source of light (lamp) that emits resonance line radiation; 2. an atomization chamber (graphite tube) in which the sample is vaporized; 3. a monochromator for selecting only one of the characteristic wavelengths (visible or ultraviolet) of the element of interest; 4. a detector, generally a photomultiplier tube (light ...
Diode-array spectrophotometers differed from the original spectrophotometer created by Beckman because it was the first single-beam microprocessor-controlled spectrophotometer that scanned multiple wavelengths at a time in seconds. It irradiates the sample with polychromatic light which the sample absorbs depending on its properties.
Infrared spectrophotometer used to analyze the diethyltoluamide insect repellent, 1960 US Food and Drug Administration scientist uses portable near infrared spectroscopy device to detect potentially illegal substances. Infrared spectroscopy is a simple and reliable technique widely used in both organic and inorganic chemistry, in research and ...
Stopped-flow spectrophotometers may function as stand-alone instruments, but they are often integrated into systems for circular dichroism (CD), absorbance, and/or fluorescence measurements, or equipped with various accessories to support specialized applications. Common stopped-flow accessories include:
The DU was developed at National Technical Laboratories (later Beckman Instruments) under the direction of Arnold Orville Beckman, an American chemist and inventor. [13] [14] Beginning in 1940, National Technical Laboratories developed three in-house prototype models (A, B, C) and one limited distribution model (D) before moving to full commercial production with the DU in 1941.
For example, with one point per wavelength of a HeNe reference laser at 0.633 μm (15 800 cm −1) the shortest wavelength would be 1.266 μm (7900 cm −1). Because of aliasing , any energy at shorter wavelengths would be interpreted as coming from longer wavelengths and so has to be minimized optically or electronically.