Ikeda M
J Opt Soc Am. 1983 Aug;73(8):1055-61. doi: 10.1364/josa.73.001055.
The summation-index technique was applied to flicker photometry to investigate the linearity law. Two test stimuli of different wavelengths were mixed, and the luminous efficiency of the mixture was measured under three different adapting conditions: no adaptation, 507-nm adaptation, and 650-nm adaptation. Most of the wavelength combinations and adapting conditions gave a summation index of 0.30, which is the linearity in the visual system that is responsible for the flicker perception, namely, the achromatic channel. An exception was the red and green combination under the no-adaptation condition, which gave a slightly smaller summation index than 0.30, indicating that these two stimuli do not add linearly. The subsummation was interpreted as cancellation of red and green responses in the red-versus-green opponent channel. The subsummation disappeared when the flicker frequency was increased from 5 to 12 Hz, confirming the interpretation.
求和指数技术被应用于闪烁光度法以研究线性定律。将两种不同波长的测试刺激混合，并在三种不同的适应条件下测量混合物的发光效率：无适应、507纳米适应和650纳米适应。大多数波长组合和适应条件给出的求和指数为0.30，这是视觉系统中负责闪烁感知的线性度，即消色差通道。一个例外是无适应条件下的红色和绿色组合，其给出的求和指数略小于0.30，表明这两种刺激并非线性相加。这种次求和被解释为红-绿拮抗通道中红色和绿色反应的抵消。当闪烁频率从5赫兹增加到12赫兹时，次求和消失，证实了这一解释。
