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Components of Optical Instruments or What’s inside that spectrometer?. Components of Optical Instruments. Signal Processor Readout. Source. Wavelength Selector. Sample. Detector. Emission Flame Photometer Flame Atomic Absorption Spectrometer Absorption Spectrometer
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Components of Optical Instruments or What’s inside that spectrometer?
Components of Optical Instruments Signal Processor Readout Source Wavelength Selector Sample Detector Emission Flame Photometer Flame Atomic Absorption Spectrometer Absorption Spectrometer Fluorescence and/or Scattering Spectrometer
Components ofOptical Instruments Emission Flame Photometer Signal Processor Readout Source Wavelength Selector Detector Sample
Components ofOptical Instruments Flame Atomic Absorption Spectrometer Signal Processor Readout Source Wavelength Selector Detector Sample
Components ofOptical Instruments Absorption Spectrometer Signal Processor Readout Source Sample Wavelength Selector Detector
Components ofOptical Instruments Fluorescence and/or Scattering Spectrometer Signal Processor Readout Sample Wavelength Selector Detector 0-90o Source
Components of Optical Instruments Fig. 7-2, pg. 145 ”(a) Construction materials
Components of Optical Instruments Fig. 7-2, pg. 145 ”(b) wavelength selectors for spectroscopic instruments."
Sources YOU TELL ME!
I l Sources of radiation Blackbody Radiation:
Monochromator – can vary wavelength – scan spectrum Prism – shorter wavelengths dispersed more
Types of gratings – most common – echellette UV-visible 1200 –1400 grooves /mm IR hundreds of grooves/mm Holographic Gratings – made by laser technology – very cheap, easy to make and very reproducible, can produce up too 6000 grooves/mm.
Effective Bandwidth – Dleff = wD-1 reciprocal linear dispersion, the inverse of the linear dispersion (D, mm/nm), which is the spreading of the light by a monochromator grating. d is the distance between blazes on the grating, and F is the focal length of the monochromator. w= slitwidth when Dy = w, Dl is the effective bandwidth
Example: To tell the difference between 589.6 and 589.0 nm light, what slitwidth would be required?