Quantitative Measurement of Sensitivity in Peripheral Visual field

当我们仔细观察物体时，我们使用的是中心凹，但当我们看到周围的环境时，我们使用的是周边视野。中心凹和周边视野的视觉特性有很大的不同。因此，为了在大尺寸显示器上呈现的大画面中获得良好的真实感，考虑周边视野的特性是重要且必要的。我们采用心理物理学的方法，在周边视野中测量了1.眼跳和追逐眼动时的视觉空间定位和移位敏感度，2.时间对比敏感度函数，3.范畴颜色知觉，4.视向作为现实知觉的指标，以量化周边视力的敏感度。本文的研究成果总结如下。该装置被构建为在外围视野中呈现大刺激同步眼球运动。结果表明，眼跳前周边视野中目标位置的刺激被较好地区分，眼跳时观察到定位的扭曲，而追踪眼动时观察不到，整个视野内的刺激位移敏感度降低。在较高的时间频率下，黄斑中心凹的时间对比敏感度函数与鼻视野中30°和40°的时间对比敏感度函数基本相等，而在刺激大小和强度相等的情况下，较低的时间频率下的时间对比敏感度函数较低。黄斑中心凹和周边视野的分类色貌基本相同，但不同视野的色泽持续不同。通过幅度估计和潜伏期作为刺激大小的函数来测量向量强度。结果表明，向量强度最大可增加到刺激大小的80°，且向量强度与质心起伏有很好的相关性。

We use the fovea when we look at an object carefully, but we use the peripheral visual field when we see our environmental world surrounding us. The visual properties are very different between the fovea and the peripheral visual field. Therefore it is important and necessary to consider characteristics of the peripheral visual field in order to obtain good reality in a large picture presented in a large-size display. We measured 1. visual space localization and displacement sensitivity during saccade and pursuit eye movements, 2. temporal contrast sensitivity function, 3. categorical color perception, 4. vection as an index of reality sensation, in the peripheral visual field by psychophysical methods in order to quantify sensitivity of the peripheral vision. Our research achievement is summarized as follows.1. Apparatuses were built to present a large stimulus synchronizing eye movement in the peripheral visual filed. The results show that stimulus at the target position in the peripheral visual field was better discriminated before saccade, distortion of localization was observed during saccade, but not observed during pursuit eye movements, and stimulus displacement sensitivity in the entire visual field was degraded.2. Temporal contrast sensitivity function at the fovea was almost equal to that at the 30 and 40 deg in the nasal visual field in higher temporal frequencies, and was lower in the lower temporal frequencies when the stimulus size and intensity were equated by the MF-scaling.3. Categorical color appearance was almost the same between at the fovea and in the peripheral visual field although color appears continuously different across visual field.4. Vection strength was measured with magnitude estimation and latency as a function of the stimulus size. It is shown that vection strength increased up to 80 deg of the stimulus size, and that vection strength was correlated well with barycentric fluctuation.