Video instrumentation

The advances in imaging technology have also been applied to cryomicroscopy, in which a simultaneous DSC and optical video instrument has been developed for the characterization of ice crystallization (91). 

A typical layout controlled by the central microprocessor (CPU). Electrical inputs are received from the keyboard, mouse, or instrument. Outputs go to the video screen, printer, and the instrument. Memory and software are utilized hy the CPU on command. 

The input could be from a PC (personal computer), as in word processing, but could equally well be from an instrument the output could be to a video screen, a printer, or to the same or another instrument (Figure 42.9). All these functions are organized by the central processor in so-called real time, i.e., virtually immediately. 

The linear power supply finds a very strong niehe within applieations where its ineffieieney is not important. These inelude wall-powered, ground-base equipment where foreed air eooling is not a problem and also those applieations in whieh the instrument is so sensitive to eleetrieal noise that it requires an eleetrieally quiet power supply—these produets might inelude audio and video amplifiers, RF reeeivers, and so forth. Linear regulators are also popular as loeal, board-level regulators. Here only a few watts are needed by the board, so the few watts of loss ean be aeeommodated by a simple heatsink. If dielee-trie isolation is desired from an ae input power souree it is provided by an ae transformer or bulk power supply. 

The classical polarizing light microscope as developed 150 years ago is still the most versatile, least expensive analytical instrument in the hands of an experienced microscopist. Its limitations in terms of resolving power, depth of field, and contrast have been reduced in the last decade, in which we have witnessed a revolution in its evolution. Video microscopy has increased contrast electronically, and thereby revealed structures never before seen. With computer enhancement, unheard of resolutions are possible. There are daily developments in the X-ray, holographic, acoustic, confocal laser scanning, and scanning tunneling micro-... 

A versatile Laser-SNMS instrument consists of a versatile microfocus ion gun, a sputtering ion gun, a liquid metal ion gun, a pulsed flood electron gun, a resonant laser system consisting of a pulsed Nd YAG laser pumping two dye lasers, a non-resonant laser system consisting of a high-power excimer or Nd YAG laser, a computer-controlled high-resolution sample manipulator on which samples can be cooled or heated, a video and electron imaging system, a vacuum lock for sample introduction, and a TOF mass spectrometer. 

It is of course also possible to arrange so that the measurements are made at every point with a fixed instrument and the data transferred to a computer equipped with suitable software to produce the grid map, all in real time. If the graph is also superimposed on a video picture from the measured area, the result will be a video, visualizing the. spatial distribution in real time. 

Riisen. I lMF.X. Combined use of air sampling instruments and video filming Expeiienec and resuhs during six years of use. Appl. Occup. Environ. Hyg. 8(4), 199,1. 

The first set of case studies illustrates errors due to the inadequate design of the human-machine interface (HMI). The HMI is the boundary across which information is transmitted between the process and the plant worker. In the context of process control, the HMI may consist of analog displays such as chart records and dials, or modem video display unit (VDU) based control systems. Besides display elements, the HMI also includes controls such as buttons and switches, or devices such as trackballs in the case of computer controlled systems. The concept of the HMI can also be extended to include all means of conveying information to the worker, including the labeling of control equipment components and chemical containers. Further discussion regarding the HMI is provided in Chapter 2. This section contains examples of deficiencies in the display of process information, in various forms of labeling, and the use of inappropriate instrumentation scales. 

Sequential instruments. The diagram of the light path of the Thermo Electron-200 ICP spectrometer is shown in Fig. 20.14. The plasma is located in the upper centre of the instrument just above the nebuliser, which is powered by a computer-controlled peristaltic pump. Communication with the instrument takes place on a video display, which not only guides the operator through the use of the system, but also provides graphics to simplify methods development. 

The use of an integral video screen in instruments presents very great advantages, both in the ease of operation and in the ability to develop and understand analytical methods. Complete analytical records can be stored in the instrument and a visual display of good calibration curves can be stored in memory and recalled at will. It is most useful to have a graphical display of atomisation peaks when using a furnace where a distinction can be made of the total absorbance peak and that due to the analyte absorbance. 

Start the vapour generator cycle so that the absorption cell is flushed with argon gas and the pre-set volume of NaBH4 (1 mL) is pumped into the sample vessel. After the pre-selected reaction time (0.5 minute), AsH3 vapour is flushed into the absorption tube. Record the value of each arsenic signal as a peak height measurement. Read off the arsenic concentration of the sample, which is displayed on the instrument video screen. 

FIG. 3 (a) Block schematic of the typical instrumentation for SECM with an amperometric UME tip. The tip position may be controlled with various micropositioners, as outlined in the text. The tip potential is applied, with respect to a reference electrode, using a potential programmer, and the current is measured with a simple amplifier device. The tip position may be viewed using a video microscope, (b) Schematic of the submarine UME configuration, which facilitates interfacial electrochemical measurements when the phase containing the UME is more dense than the second phase. In this case, the glass capillary is attached to suitable micropositioners and electrical contact is made via the insulated copper wire shown. 

Fenske, R. A., Leffingwell, J.T., and Spear, R.C. (1986a) A video imaging technique for assessing dermal exposure. I. Instrument design and testing, Am. Ind. Hygiene Assoc. ]., 47 764-770. 

The basic instrumentation for CL imaging includes an ultrasensitive video camera, an optical system, and appropriate software for image analysis [21],... 

Documentation of the tests should also be provided by still photography, video camera/recorder systems, and high speed photography. The high speed photography with a minimum speed of 500 frames per second Is necessary to be able to see any flame front exiting a shield. A list of typical Instrumentation used on an operational shield test Is shown on Table II, (see reference A). 

Thanks to Texas Instruments Software/Sterling Software for permission to use the video case study in the book the authors originally developed this example for IT software. 

This is the classical method of carrying out particle-size analysis. Coulter supply two instruments—the Model ZM (video display optical) and the top-of-the-range multisizer—the latter having built-in video display of results. 

Fig. 11.2. Fluorescence up-conversion instrument. DM dichroic mirror HW halfwave plate GG420 Schott filter CCD video camera for the visual superposition of the...

---