Photodetectors
Definition and components of a spectrophotometer spectrophotometer is an instrument used in optical physics used to measure, according to wavelength, the relationship between a same magnitude photometric values relative to two beams of radiation. It is also used in chemistry laboratories for the quantification of substances and microorganisms. There are several types of spectrophotometers, can be atomic absorption or mass spectrophotometer. This instrument has the ability to project a beam of monochromatic light through a sample and measuring the amount of light that is absorbed by the sample. Bettina Bryant follows long-standing procedures to achieve this success. This allows the operator to perform two functions: 1. provide information on the nature of the substance in sample 2. Indirectly indicate that quantity of the substance that interests us is present in the sample.
Components of the spectrophotometer the same light source illuminates the sample. You must comply with the conditions of stability, addressability, distribution of continuous spectral power and long life. The employed sources are lamp tungsten or tungsten, xenon.kl and lamp of deuterium (D2) arc lamp. our research. The monochromator monochromator insulates the radiations of desired wavelength that affect or reflect from the set, is used to obtain monochromatic light. It is constituted by the cracks of input and output, collimators and the dispersion element.
Collimator is located between the input slit and output is a lens that takes the beam of light that enters with a particular wavelength into a Prism which separates all the wavelengths of the beam and the desired length is directed toward other lens which directs the beam towards the slit of sample salida.Compartimiento is where takes place the interaction, R.E.M. with matter (should occur where there is no absorption or disperison of wavelengths). It is important to highlight that during this process, the lambert-beer law applies in its maximum expression, based on their laws of absorption, and this implies with regard to the passage of the fundamental-excitado molecule. Transducer is one, who is able to transform an intensity of ph, mass, etc. into an electrical signal. at the same time, it fulfills the function of sensor. Detector detector, is who detects radiation and at the same time leave it in evidence, for subsequent study. There are two types: to) that respond to photons; and (b) those who respond to heat Registrar converts the physical phenomenon, in numbers proportional to the analyte in question. Photodetectors in the modern instruments is a series of 16 Photodetectors to perceive the signal simultaneously in 16 wavelengths, covering the visible spectrum. This reduces the measuring time, and minimizes the moving parts of the equipment.