Optical diagram

Figure 5.8 Scheaatic optical diagram of a variable wavelength dual beam absorption detector. A, and a photodiode array detector with reverse optics, B.

The optical diagrams, components used and their modes of operation shall be discussed briefly in this context under different heads. 

Figure 22.2. Optical Diagram of a Single-Monochromator Infrared Spectrophotometer.

The schematic optical diagram of a double-beam infrared spectrophotometer has been shown in Figure 22.3 as per Beckman Model IR-9. 

Figure 22.3 Optical Diagram of a Double-Monochromator Infrared Spectrophotometer (Beckman Model IR-9)...

Describe any ONE of them with a neat-labeled optical diagram and its modus operandi. 

Figure 2.29 Optical diagram of a double-beam spectrophotometer. Interchangeable lamps are available for work in the visible and ultraviolet regions and monochrornation...

For clarity and precision in the following discussion, the 5-m Littrow spectrometer at the University of Tennessee at Knoxville will serve as the prototype (Jennings, 1974). The optical diagram is presented in Fig. 1. The system is used as an absorption spectrometer most of the discussion also applies to acquisition of emission spectra. 

Fig. 1 Optical diagram of the prototype system model. The drawing is not to scale and is not to be considered an optical ray diagram. The principal dispersing element is a coarse echelle ruled grating 20 x 40 cm wide. Theoretical double-pass resolution at four normal slits is approximately 0.095 cm-1 actual achievable resolution is approximately 0.009 cm-1.

Figure 10.11—Optical arrangement of a Fourier transform IR spectrometer, a) A 90c Michelson interferometer including the details of the beam splitter (expanded view) b) optical diagram of a single beam spectrometer (based on a Nicolet model). A weak intensity HeNe laser (632.8 nm) is used as an internal standard to measure precisely the position of the moving mirror using an interference method (a simple sinusoidal interferogram caused by the laser is produced within the device). According to the Nyquist theorem, at least two points per period are needed to calculate the wavelength within the given spectrum.

Figure 15.7—Optical diagrams for a spectrophotometer with an echelle grating. Model PU 7000 optical system (reproduced by permission of Philips). All spectral lines are captured, which allows a more complete study of the sample. The dynamic range of these instruments is still lower than that of a PMT.

An optical diagram of a Johansson curved-crystal spectrometer is given in Fig 9. F.ach spectrometer of an x-ray qnantometer may be equipped with optimum crystal-detector combinations for specific determinations in a wide variety of matrixes, including steel, aluminum, copper-base materials, ores, cement, and slags—in both liquid and solid states. 

Fig. 9. Optical diagram of Johansson curved-crystal spectrometer...

An optical diagram of the Farrand instrument is shown in Figure 4. The excitation light goes successively through the optical system, the first raono-... 

Figure 2-9 Optical diagram of an FT-Raman spectrometer. The heart of the instrument is the interferometer head, consisting of the beam splitter and fixed and moving mirrors.

Figure 2-32 Optical diagram for fiber optic probe used with the spectrometer in Fig. 2-31. (Reproduced with permission from Raman Systems, Inc.)...

Figure 9.28. Optical diagrams for refractive index detectors for LC (a) Fresnel type by permission of LDC/Milton Roy (h) deflection type by permission of Millipore Corporation, Waters Chromatography Division.

Cary 14 diagram (ca. 1953) The arrows on the optical diagram trace the path of the UV and vis radiation through the instrument. Radiation from the D2 or W lamp is directed to the monochromator entrance slit D by appropriate lenses and mirrors. From mirror E it travels to prism F where it is refracted, then to mirror G which reflects it to variable-width intermediate slit H. Mirror I reflects the radiation to grating J and from there the monochromatic beam is directed to mirror K and exits the monochromator through slit L. Semicircular mirror O, driven by motor Q, chops the beam at 30 Hz and alternately sends half the beam to the reference and half to the sample. Elements V, V1, W, and W1 pass the separated beams to the phototube. The light pulses of the two beams are out of phase with each other so that the phototube receives light from only one beam at a time. The photomultiplier for UV-vis work is shown at X and the NIR detector for 700-2600 nm is shown at Y. 

Fig. 8.2.1. Low angle laser light scattering photometer (Chromatix KMX-6) simplified optical diagram. 1 Flelium-neon laser 2 prism system 3,4,5 measuring attenuators 6 calibrating/ shutter attenuator 7 condensing lens 8 sample compartment 9 annuli 10 safety attenuator 11 relay lens 12 field stops 13 interference filter 14 analyzing polarizer 15 microscope objective 16 photomultiplier...

Optical diagram of Varian-Cary models 219 and 2000 series double-beam spectrophotometers (available as models 400 and 500 from Varian). 

Typical optical diagram of the Mattson series of FTIR instruments. Courtesy of Mattson Instruments, Inc. 

As an example of a modern commercial interferometer, the optical diagram of a Bruker IFS 66, is shown in Fig, 3.4-1. It allows working in the optical range from 40000 to 20 cm (250 nm to 500 im), to exchange different internal and external radiation sources and detectors, and to connect various accessories, such as a Raman module or an infrared or Raman microscope. 

Figure 3.4-1 Optical diagram of a commercial Michelson interferometer for infrared and Raman spectroscopy (Bruker IFS 66 with Raman module FRA 106). CE control electronics, D1/D2 IR detectors, BS beamsplitter, MS mirror scanner, IP input port, S IR source, AC aperture changer, XI — X3 external beams, A aperture for Raman spectroscopy, D detector for Raman spectroscopy, FM Rayleigh filter module, SC sample compartment with illumination optics, L Nd.YAG laser, SP sample position.

Optical Diagram of a Low Angle Laser Light Scattering Detector Courtesy of LDC Abalytical, Thermo Instruments Corporation. 

Figure 25-1 9 The Spectronic 20 spectrophotometer. A photograph of the instrument is shown in (a), while the optical diagram is seen in (b). Radiation from the tungsten filament source passes through an entrance slit into the monochromator. A reflection grating diffracts the radiation, and the selected wavelength band passes through the exit slit into the sample chamber. A solid-state detector converts the light intensity into a related electrical signal that is amplified and displayed on a digital readout. (Courtesy of Thermo Electron Corp., Madison, WI.)...

Figure 9.23 Optical diagram of a simple specular reflectance accessory for FTIR instrument.

Figure 9.24 Optical diagram of a diffuse reflectance accessory for an FTIR instrument.

Figure 9.29 Optical diagram of a Raman microscope. A pinhole spatial filter consists of a pinhole confocal diaphragm (Dj and D2). (Reproduced with permission from G. Turrell and J. Corset, Raman Microscopy, Developments and Applications, Academic Press, Harcourt Brace Company, London. 1996 Elsevier B.V.)...

Figure 9.8 Schematic optical diagram of the ATR accessory FastIR, demonstrating the different angles of incidence on the interface of the sample and the ATR reflection element. Adapted from http //www.harricksci. com/accessories/H fastir.cfm. The variably...

Figure 2. PMS LAS-X Optics Diagram. (Reproduced with permission. Copyright Particle Measuring Systems Inc.)...

Fig. 44, Optical diagram of the Digilab FTS 14 Fourier spectrometer (No. 4 b in Tables 2, 3, 4)...

The optical layouts of the instruments are very similar, especially those of the instruments for the middle- and near-infrared. For comparison, the optical diagrams of three such instruments are reproduced in Figs. 44 (No. 4 b, Digilab FTS 14), 45 (No. 2b, Bruker IFS 115), and 46 (No. 5b, Pol5dec MIR 160). Clearly, the essential part of the optical layout is the Michelson interforometer with the... 

Fig. 46. Optical diagram of the Polytec MIR 160 Fourier spectrometer (No. 5b in Tables 2, 3, 4). M 1, M 2, M 5, M 6, M 7 plane mirrors M 3, M 4 paraboloid mirrors MS spherical mirror MT toroid mirrors G Globar source S high pressure Hg-lamp L He-Ne-laser IS Interferometer scanner BS beampslitter PC photo-cell D pyroelectric detector WL white light source...

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