Horizontally polarized light

Describe the angular dependence of the vertically and horizontally polarized light scattered by a molecule and their resultant by considering the intensity as a vector anchored at the origin whose length in various directions is given by the trigonometric terms in Eqs. (10.25), (10.26), and (10.30),... 

Fig. 19. Hypothetical orientation of the SO - SI transition dipoles (blue band) of the bluelight photoreceptor in the Phycomyces sporangiophore as concluded from polarized light experiments96). Horizontally polarized light is about 20% more effective than vertically polarized light, as sketched...

When using horizontally polarized light, Eq. (B.10) is multiplied by the polarization factor cos20, while with the use of unpolarized light the polarization factor is (1 + cos2 8)12... 

The attenuated total reflection (ATR) method measures the reflection coefficients of vertically and horizontally polarized light reflected from a polymer layer adsorbed on a transparent surface63. These coefficients allow the thickness of the adsorbed layer and the polymer concentration in it to be determined. 

Such a crystal is double refracting since the two values of the refractive index will cause the two polarizations to propagate along different paths. Separation of the two polarizations occurs at the interface where the horizontally polarized light is totally internally reflected. The vertically polarized light, on the other hand, is transmitted across the interface where the second half of the polarizing cube returns this polarized beam to its... 

Such a device has the property to convert unpolarized light into horizontally polarized light, eliminating all vertical components of the unpolarized radiation. Therefore, the overall beam intensity of the polarized beam would be half of that of the unpolarized one, i.e. 

FIG. 16.23 Writing and reading with various polarization directions (a) Readout results of data that were recorded with the polarization angles from 0° to i80° with a pitch of 15°. The data were read out with four polarization states, (b) Polar plot of readout intensity of data with the (unction of the polarization direction of the readout beam. Data were recorded with the horizontally polarized light in this figure,... 

The intensity of unpolarized portion of scattered light, 7U, is twice the intensity of horizontally polarized light, i.e. ... 

In a practical experiment, a correction factor is introduced to take into account the sensitivity of the fluorescence spectrometer to anisotropy. The factor G = /hv//hh is used, where the subscript v and h correspond to the vertically polarized light (z direction) and the horizontally polarized light (x- and -axes), respectively, with the incident light polarized in the.v direction. Taking this correction factor into account, the value of the fluorescence anisotropy ratio is... 

To calculate the actual intensity ratio (Mix), we need to determine the G-factor, which is the ratio of the sensitivities of the detection syston for vertically and horizontally polarized light. 

In the n) nmasureinents, one chedas for a sensitivity to polarization by excitation with horizontally polarized light The measured values of the differential polarized phase angle (AJ should be zero. Also, the measured value of the modulation ratio (A,) should be 1.0. If needed, FD anisolropy decays can be measured m a T-format to avoid rotating the emission polarizer."... 

Both excitation and emission polarizers could be adjusted to transmit either vertically (0°) or horizontally (90°) polarized light. The two monochromators had different transmission eflSciencies for the vertically and horizontally polarized light that modified the actual measured intensities. This difference in sensitivity is commonly referred to as the G factor and must be determined in order to obtain polarization measurements. We employed the method of Lakowicz to obtain the G factor and to calculate polarization values. 

Figure 2.2. Schematic illustration of scattering of horizontally polarized light...

Let the particle be illuminated by linearly polarized light from negative x values with its plane of polarization matching the plane of scattering (horizontally polarized light) with the electric field strength vector... 

A A/2-plate with its fast axis in the x-direction is rotated by an angle 9 around the z-axis (direction of light propagation). If linear horizontal polarized light passes through the device the output light is... 

Linearly polarized light provides another instructive illustration of superposition states in quantum optics. As discussed in Sect. 3.3, unpolarized light can be viewed as a mixture of photons with all possible linear polarizations. Light that is polarized at an angle 6 with respect to an arbitrary vertical axis can be viewed as a coherent superposition of vertically and horizontally polarized light with coefficients Cy=cos(0) and Ch = sin(0) ... 

Fluorescence anisotropy can also be calculated by the quotient between the fluorescence intensities obtained at the four different combinations of the excitation and emission polarizer positions, as shown by Equation (12.3), Iw and Ihh account for the fluorescence intensity obtained with both polarizers at the vertical and horizontal position, respectively. Ihv corresponds to the fluorescence emission obtained with excitation polarizer horizontally and emission polarizer vertically oriented. In contrast, lyn corresponds to the fluorescence emission obtained with excitation polarizer verticahy and emission polarizer horizontally oriented. The G factor (Equation 12.4) is a parameter that accounts for the sensitivity of the detection system for verticahy and horizontally polarized lights [3]. 

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