Optical system for real-time time-resolved simultaneous measurements of both VH and HH static light scattering. L: Laser; ND: Neutral density filter; HW: Half wave plate; BE: Beam expander; M: Mirror; SF: Spatial filter; AL1: Aspheric lens f = 6.5 mm; BS: Beam splitter; CH: Optical chopper; GL: Glan-laser prism; PD: Photodiode; HS: Hot stage; SC: Sample cell; OL: Microscope objective lens for polarizing observation; AL2: Aspheric lens f = 90.8 mm; GT: Glan-Thompson prism; CL: commercial lens f = 35 mm; CCD: charge coupled device camera; VM: digital volt meter; CC: optical chopper controller; PC: personal computer with frame grabber board. CH and CCD were synchronized with a control signal from the frame grabber board in PC.
Glan-laser prism for coupling the two laser lines with different polarization directions. The intensity of a light signal V from laser line 1 reflected by the air gap of the prism was monitored by a photodiode (PD in Fig. 1) during light scattering measurements to monitor the incident laser power.
VH scattering images captured by two different optical systems. (a) An image captured by the system shown in Fig. 1. A fourfold pattern is clearly captured. (b) An image captured by the optical system shown in (c). A ring-like pattern of HH scattering is superimposed on the fourfold VH pattern. (c) Laser lines coupled by an ordinary beam splitter with two polarizers; FP: film polarizer; GT, M3, M4: the same as Fig. 1.
Time evolution of the light scattering pattern in the process of phase separation of the OS/OB mixture. These images are observed on the back focal plane of the OL in Fig. 1, which has a circular image boundary (its radius ∼5.3 μm, see text). (a) VH scattering patterns, I VH. (b) HH scattering patterns, I HH. The directions of the polarizer and the analyzer are the horizontal (H) and vertical (V) directions in the image plane, respectively. These images were shown after the background subtraction. To avoid the saturation of signals, the absolute intensity is suitably modified with time. The white bar corresponds to 5 μm−1.
Temporal change of the HH scattering function S HH(q) during the spinodal-decomposition process of OS/OB.
Temporal change of the VH scattering function S VH(q) in the spinodal-decomposition process of the OS/OB mixture. The inset shows the azimuthal angle dependence of I VH at q = 4 μm−1. The distortion of the fourfold symmetry is due to some non-ideality of our optical system. The intensity of S VH(q) is divided by (see text).
Time evolution of q m and estimated from Fig. 5, during the spinodal-decomposition process of OS/OB.
Temporal change of the ratio of S VH(q) to S HH(q), R(q), for the OS/OB mixture undergoing phase separation and its comparison with the theoretical prediction. The measurement was made by using the objective lens for polarizing microscopy.
Temporal change of the ratio of S VH(q) and S HH(q), R(q), in OS/OB using a usual objective lens (not for polarizing observation). The other experimental conditions are the same as in Fig. 8.
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