It is expected that the properties of human visual receptive field change due to the state of adaptation. The receptive field properties may be described by the line spread function l (χ). However we have no easy direct psychophysical method to measure l (χ). Instead of the autocorrelation function of l (χ) can be decided directry if we utilize the two stimuli method. In this method the additivity of two narrow line stimuli is measured and then the auto-correlation function of l (χ) is calculated from the degree of additivity for various stimuli separations. The auto-correlation function of l (χ) were investigated for three kinds of adapting field. Then it was found that on high adapting field luminance the auto-correlation functions of l (χ) had positive and negative phases which represented the excitatory and inhibitory property of receptive field. On the contrary the auto-correlation function of l (χ) on low luminance adapting field had no negative phase. Therefore it was suggested that the excitatory area enlarged and the inhibitory response decreased when the adapting field luminance lowered.

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The spatial double stimuli method is used to measure the receptive field properties. However the methodology of this method has not been investigated enough, and it is difficult to compare the results which were obtained with different experimental conditions. In measuring the receptive field properties it is necessary to avoid the influence of non-linearity at the other portion of the visual system. In this report we counted up four kinds of non-linearity which affected the measurement of receptive field properties. And then it was clarified that the spatial double stimuli method was superior than MTF method and one stimulus method. We showed that line spread function could be calculated from the experimental results of spatial double stimuli method by introducing the generally acceptable threshold determination process. The line spread functions were actually obtained from three different experimental results and they were compared each other.

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A new ellipsometric technique which is realized by a stabilized transverse Zeeman laser (STZL) which emits light composed of two orthogonally polarized components with different frequency is proposed and analyzed by the Mueller matrices calculus. The small in-plane anisotropy of multilayer dielectric laser mirrors has been determined with the new technique. It has been demonstrated that the birefringent anisotropy dominates the dichroic anisotropy, and even the dominant birefringence is of the order of 0.03 degree.

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The light of stabilized 633 nm He-Ne transverse Zeeman laser (STZL) is composed of two linearly polarized components in orthogonal relation and with different frequencies. Using an STZL the optical phase of the two-beam optical interference is converted to the phase of the photo-electric signal. A technique to determine the fractional order of the interference by multiplying the frequency of the photo-electric signal is proposed and demonstrated.

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