Briefly describe Weber's law.
Only the perceptible difference is not fixed, but varies with the original stimulus intensity. However, the ratio of the just obvious difference to the original stimulus intensity is a constant. That is, δ I/I = K. Weber's law is only applicable to moderate stimulus intensity, and Weber's score increases near the lower limit; Weber's score dropped near the upper limit.
Brief introduction of Fechner's law.
There is not a one-to-one correspondence between psychological quantity and physical quantity of stimulus. It does not mean that the physical quantity of stimulation increases by one unit, and the psychological intensity caused by it also increases by one unit. Fechner thinks that just perceptible difference can be used as the unit of feeling, and the psychological intensity caused by a stimulus can be expressed by the difference threshold contained in this stimulus. S=KlgR .s stands for psychological quantity, r stands for physical quantity, and k is a constant. The intensity of sensation is directly proportional to the logarithm of stimulus intensity, which increases in logarithmic series, but the psychological intensity it causes only increases in arithmetic series, which is Fechner's law. It is only suitable for moderate intensity stimulation.
Introduction to visual adaptation.
The suitable visual stimulus is visible light with a wavelength of 380~780nm. The most typical visual adaptation is dark adaptation. The so-called dark adaptation refers to the phenomenon that visual sensitivity changes due to working in a dark environment for a long time. Dark adaptation usually takes 30 to 40 minutes, while light adaptation only takes one or two minutes to complete. After dark adaptation, I was accidentally stimulated by light, and the dark adaptation was destroyed. The process of light adaptation is the process of rhodopsin decomposition on retina under the action of light; Dark adaptation is a process of rhodopsin biosynthesis.
Briefly describe the abnormal color vision and its causes.
Some people have difficulty in distinguishing colors, or even can't tell them apart. This is called abnormal color vision. Divided into: weak color, partial color blindness and color blindness. Color vision abnormalities are mostly caused by genetic reasons. Genetic approach: the boy's grandfather passed it on to himself through his mother. Only when both parents are color blind can a daughter be color blind. So male color blindness is far more than female color blindness.