Band pass filter set

The spectral irradiance of a typical mercury xenon lamp is shown in Figure 45. There is a characteristic high intensity mercury emission at 313 nm and a low intensity emission at 334 nm The MUV projection printing tools isolate these two lines through insertion of band-pass filter sets into the optical path, such that little or no light to the blue of 300 nm or to the red of 350 nm is transmitted to the resist surface. The transmission of a filter set of this sort for the Perkin Elmer Micralign 500 is shown in Figure 46. 

Multicavity interference band-pass filter sets (Omega Optical, Inc., Brat-tleboro, VT). Wavelengths (center of pass band half band width) Hoechst fluorescence (filter set XF06) ex. = 365 12.5 nm, em. = 450 32.5 nm FITC immunofluorescence, (filter set XF22) ex. = 485 11 nm, em. = 530 15 nm... 

With wide field fluorescence microscope, examine the cultures for fluorescence with a 488 band pass filter set and with a 546 long pass filter set (explanation in Chapter 13, Microscopy and Images). With the CCD camera configure the software and hardware for capturing the images. 

Figure 5-32 is a block diagram of the ANL acoustic cross-correlation test section (Sheen and Raptis, 1986) for monitoring solid/gas flows. Three pairs of wide-band transducers are clamped directly on the pipe. In each pair, one transducer acts as a transmitter and the other as a receiver. To avoid acoustic crosstalk, each pair of transducers is acoustically isolated from the others. The isolation is achieved by using viton gaskets between flanges. During operation, the transmitters delivered a continuous wave with a frequency of 1 MHz. Receivers were conditioned with amplifiers and band-passed filters set at 100-1... 

A hexapole assembly of rods (poles) is built similarly to the quadrupole, but now there are three sets of opposed rods evenly spaced around a central axis. The hexapole cannot act as a mass filter by applying a DC field and is used only in its all-RF mode. It is therefore a wide band-pass filter and is used to collimate an ion beam. (Like-charged particles repel each other, and an electrically charged beam will tend to spread apart because of mutual repulsion of ions unless steps are taken to reduce the effect.)... 

The main problem has been a methodological one. The patch clamp analysis of single channels views the world of channels through a very small analytical window [10]. A single channel event (opening) needs to be sufficiently long-lived and sufficiently large to be picked up within the current noise band under optimized conditions, and with the low-pass filter set to say 2 kHz. The open time needs to be close to a millisecond and the current amplitude close to 0.5 pA to permit detection. 

The same system was used to record temporal data from a H2/air flame using spectral band-pass filters. Fig. 6 shows water flame spectra obtained under two different flame conditions a near stoichiometric flame and a lean flame. The spectral data match the known theoretical spectra of water. The width of the spectral band is an indicator of water temperature. Thus, we can determine the density and temperature of the water vapor within the flame using a set of three spectral bands corresponding to the center and wing of the water band, and a null band outside of the water radiation band. 

For the sake of simplicity, let us now set up the case of a second-order bandpass filter and a comparator with saturation levels This closed-loop system verifies the required premises the system is autonomous, the nonlinearity is both separable and frequency-independent, and the linear transfer function contains enough low-pass filtering to neglect the higher harmonics at the comparator output. Choosing adequately the band-pass filter, it can be forced that the first-order characteristic equation for the closed-loop system of Fig. 4 has an oscillation solution being and the oscillation frequency and... 

A fluorescence detection system is quite similar to aUV-visible absorbance detection system, except that a laser light source or a LED with high output power is used, a set of band-pass filters must be present to select appropriate wavelengths for the excitation and emission light to achieve precise measurements, and fluorescent tags must be attached to the target particles if necessary. 

Elimination of the noises is one of the most concerned aspects in the applications. Usually, it is achieved by simply setting the threshold level over the noise level, or by a band-pass filtering and a post-analysis of the data. In any cases, the averaged amplitude of the noise should be managed to be lower than 10 AV as input. 

A measurement system consists, as given in Fig. 2.8, of AE sensor, amplifier, and filter. Total amplification by the pre-amplifier and the main amplifier is usually set from 60 dB to 90 dB. To decrease the noises, a band-pass filter between several kHz and 1 MHz is mostly desirable. The noises should be lower than 20 pV as input voltage after detected by AE sensors. 

The fluorimeter is set to 340 nm excitation and 420 nm emission wavelengths for monochromator instruments. For filter instruments the corresponding filters are used. In this case the excitation filter should be a narrow band pass filter ( 10 nm), while on the emission side a cut-off filter (>420nm) may be used. The fluorimeter output is fed to a linear mV recorder, a data logger, or any other signal processing system. The peak heights are proportional... 

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