1. Recognize colors How color is formed has attracted people's attention since ancient times. Since the 1930s, color science that takes color as a research object has become an emerging applied technology, which has been valued by the scientific and technological circles and industry. In the surrounding environment of our life, color surrounds you almost everywhere. Color has a very close relationship with everyone, for example, food, clothing, housing, travel, education, joy, etc .; and color affects everyone's emotions , Emotion, personality also has a profound impact. So what is color? How do colors come about? And how do objects form color after being stimulated by light? What are the basic requirements for forming color? The average person must be quite vague about such problems, because the knowledge of color is relatively poor, and the technical field of color includes mathematics, physics, chemistry, physiology and psychology and other scientific knowledge, so in order to establish the reader's correct color technology basic The concepts will be elaborated one by one in future articles, introducing concepts and knowledge about color technology. The sense of color is an intricate and complex process. According to scientific explanations and definitions-the main factor of color formation is that after the light source illuminates the object, the light that it transmits (or reflects) stimulates the naked eye to produce color. Feeling, so the formation of color is not only related to the stimulation of light, but also to the visual organs of the naked eye. For the above explanations and definitions, we can clearly understand the basic requirements of color formation: 1. light source, 2. object, attenuator, 3. viewer, observer, for color The basic elements of formation. Since color is a phenomenon caused by light stimulation of the retina of the naked eye, light plays a crucial role in the formation of color. But what is light? Light is an electromagnetic wave, because light has the characteristics of reflection, interference, polarization and other waves, and the phenomenon of light absorption between light and objects, it is also a light quantum with energy, so light has both wave and quantum physics characteristic. The physical characteristics of light are determined by the wave and energy of light-the wavelength of light determines the color of light; the energy of light determines the intensity of light. Since the range of electromagnetic waves is quite large, they include cosmic rays, ultraviolet rays, visible light, infrared rays, microwaves, etc., but the electromagnetic waves that can really produce color perception in the visual system of the human eye are visible light waves, with a wavelength range of about 380nm to 780nm In this visible spectrum, electromagnetic waves of different wavelengths produce different color perceptions. A general light source is a compound color light composed of monochromatic light of different wavelengths. The so-called "monochromatic light" refers to white light or sunlight refracted by Mitsubishi mirrors to separate spectral color light-red, orange, yellow, green Seven colors, such as, blue, indigo, and purple, because this decomposed color light will not be decomposed into other color lights even after passing through the Mitsubishi lens again, so this color light that cannot be decomposed is called monochromatic light; and The light mixed by "monochromatic light" is called "multicolor light". The light emitted by the sunlight in the nature and the artificially made fluorescent lamps are polychromatic. After a preliminary understanding of the nature of light, we will further explore the effect and effect of color produced by light shining on objects. Objects in nature can be divided into two categories: 1. Illuminant-refers to an object that can radiate light to the surrounding space, also known as a light source. 2. Non-luminous body-refers to all substances other than luminous body in nature. Non-luminous bodies can only display color when illuminated by a ground light source, so without light, the color of the object cannot be seen, and there is no color feeling. Different objects have different molecular and atomic structures. Therefore, when the incident light irradiates the object, when the incident light of a certain wavelength matches the characteristics of the object itself, the object absorbs the incident light of this wavelength, and the remaining Colored light reflects out, showing the color of the object, so the reason for the color formation on the surface of the object is the result of the selective absorption and reflection of light by the object. The color of the object that people see is the reflected or transmitted color light after the light interacts with the object. In addition, the absorption of incident light with a wavelength that matches the characteristics of the object itself will cause the electron energy level of the object to jump to the orbit of the high energy level. This phenomenon is called light absorption; and because the electron energy level jumps to the high energy level. The orbit is relatively unstable, so the electrons then return to the original stable orbit, and release the absorbed radiation energy in the form of heat, or partly in the form of radiation energy. So what color an object exhibits is related to the object's selective absorption of monochromatic light of various wavelengths in visible light, and the selective absorption of an object's monochromatic light of various wavelengths in visible light depends on the physical properties and chemical structure of the object itself. Light is the only reason the human eye perceives color; the color of an object is the characteristic of the object itself to light stimulation. Finally, we can get the following conclusions-"Natural matter itself can be said to be colorless, because the object itself absorbs light of different wavelengths in the light source and produces selective absorption of light waves, which determines the color of the object itself. Therefore, there is no light Colorless, it is the light source endows the nature with colorful and colorful colors; the light source is the first element of color appearance, and the change of the light source has an absolute impact on the color appearance. " Second, the human visual color system The color is mainly generated because the human eye receives the reflection or transmission from the surface or inside of the object to the light source, so the color is covered by three major factors such as light, object characteristics and human eye vision mechanism. In the previous article, the light source is irradiated to The effect of objects has already been explained, and in this article, the reason for how colors can be felt after the light reflected or transmitted by the object enters the human visual system. The eye is the window of the soul, which plays the role of evaluation, viewing and judgment. However, how does the eye accept the reflection (transmission) or light emitted by external objects to make people feel the color? First of all, we must understand that the electromagnetic waves that can produce color perception on the visual system of the human eye are visible light waves, and the wavelength range is about 380nm to 780nm. However, in this visible spectrum, various electromagnetic waves of different wavelengths can produce different colors Feeling, and the colors of natural Shu have hundreds of millions of colors, so how does the human eye's visual system recognize the color stimulation generated by the light reflected or transmitted by the object? The main reason is that the photoreceptor cells in the human eye's visual system? The results of the action of rod-shaped cells and cone-shaped cells will be described below with respect to the visual characteristics of the above-mentioned visual photosensitive cells: Rod-shaped cell Rod-shaped cells only work in darker conditions. Their brightness is below 0.01 nits. They are high-sensitivity and low-resolution cells. They can only recognize changes in light and dark, and have no sensory effect on color. It is said that rod-shaped cells only have a black-white light-dark sensation effect on light. Its sensitivity range is 400 ~ 600nm. 2. Cone cells Since the cone-shaped cells do not work under weak light, they are low-sensitivity cells and are suitable for daytime vision; but when the brightness is up to several nits, the cone-shaped cells can distinguish Colors and details of objects are low-sensitivity, high-resolution cells. Cone cells contain three different types of color-sensing cells, which are for the perception of long-wavelength red colored light-(cone-shaped cells, medium-wavelength green colored light-(cone-shaped cells and short-wavelength blue colored light-( Cone cells, so cone cells can distinguish colors. The sensitivity range is 400 ~ 700nm. The maximum sensitivity points of three different types of color sensitive cells for the spectral wavelength are in the blue color range of the visible spectrum. 420nm, green color light-530nm and yellow-green light-560nm, the ratio of the number of three different types of color-sensing cells on the retina is approximately Ï: γ: β = 40: 20: 1. Therefore, through the above explanation, we can understand that the main reason why the human eye perceives color is due to the overlapping spectrum characteristics of three different types of color-sensing cells on the retina, so that each wavelength in the visible spectrum has The only absorption rate, through the absorption ratio of these three cone cells, the human eye's visual system can distinguish the color of the object. In addition, because the human eye has three different cone-shaped cells, the "color theory of three primary colors of visual color", which has been dominant in color science for many years, has been developed in the theory of color vision- , The "visual color three primary color theory" will be explained in the next color technical article. Third, the three primary colors of visual color The Theory of Color Vision is developed based on the human visual system's color recognition mechanism. Its purpose is to hope that these color vision theories can explain or help researchers understand and master the visual and color produced by the naked eye. Phenomenon and relationship. After years of research, the theory of color vision can be summarized into the following three theories: 1. Three-component or Trichromatic Theory 2. Opponent-colors Theory 3. Zone Theory of Color Vision The "visual color trichromatic theory" is the earliest theory that has been put forward in color science; the "opposite color theory" was later proposed. This theory is another one in addition to the visual color trichromatic theory Important theories are also valued by the color science community; although these two color vision theories can explain most of the visual color phenomenon, there are also "stage visual color theories" proposed in recent years and accepted by everyone. And this-the doctrine is a combination of the basic concepts of "the theory of three primary colors of visual color" and "the theory of color of opposing colors", which are unified and complemented with each other. As for the detailed contents of the three color vision theories, they will be explained in the color technology monographs. In this article, we will first discuss the "visual color three primary color theory". In 1802, British Tomas Young discovered that the use of red, green, and blue colors can produce a variety of colors, so he published and proposed the theory of the three primary colors of color; and in 1861, the British Maxwell used the mixing method of three primary colors The first color photo; this theory reached the end of the 19th century? In 1892, Helmholtz in Germany verified and elaborated on his theory, so the theory of the three primary colors of visual color was also called "Young-helmholtz theory of three primary colors of color". According to his doctrine, the three visual cells on the human retina are named after being connected to three different nerve cells in the cerebral cortex. The stimulation of each cell will cause a primary color sensation? There are three colors of red, green, and blue. This argument has detailed information in the previous article, and readers should have some impressions. When the light reflected (or transmitted) by the light irradiation object enters the human visual system, it will simultaneously cause stimulation of three different types of cells, and the wavelength characteristics of the light make the three cells each have a different ratio of the total intensity of stimulation. Produce a variety of different colors. This theory was put forward by Tomas Young in Britain. When a certain color sensation occurs, there will be one of the three types of cells that has the strongest stimulation, but the other two types of cells will also have some stimulation, that is, all three types of cells will be stimulated, so for each A color will have a white light component, that is, a sense of lightness. The brightness sensation is the sum of the brightness sensations provided by each of the three cells. Later, German helmholtz supplemented Tomas Young ’s theory that different parts of the spectrum can cause stimulation of different strength ratios of three different cells. The color seen in the mixed shade is the result of the stimulation of three different cells, and this argument is proposed. The monochromatic light other than red, green and blue colors can be more reasonably explained by the eyes. In short, any color seen by the eye is the result of the total stimulation after the three visual cells are stimulated by light. The biggest advantage of Young-Helmholtz's theory of three primary colors is that it can fully explain the mixing phenomenon of various colors and solve the problem of color reproduction. For example, the color reproduction of color movies and color TVs is developed based on this theoretical basis; The hypothesis of the three photoreceptor cells has also been proved in the experimental results, laying the basic concept of spectral tristimulus value. This theory can be said to be the root of the development of modern "colorimetry". But the disadvantage of this color vision theory is that it cannot explain the phenomenon of color blindness (Color Blindness) satisfactorily. As far as the phenomenon of color blindness is concerned, Helmholtz believes that color blindness is caused by the lack of one type (monochromatic blindness) or two or even three types (full color blindness) of cone cells. Color blindness and blue blindness can exist separately, but in fact all red blind people are also green blind people at the same time, that is to say, red blind people generally cannot distinguish between red and green, called red-green blindness; at the same time according to their theory Inferred that red-green blind people should not have a yellow feeling-because red-green blindness lacks red and green cone cells, and the yellow color feeling is formed by the induction of red and green cone cells, but in fact red-green Blind people have the same yellow feeling; in addition, according to their theory, only three kinds of photoreceptor cells can have a neutral color at the same time-white or gray feeling. Color blind people lack at least one of the cone cells. Should they not have a neutral color? It feels white or gray, but even a person who is completely color-blind has the feeling of lightness or white. So as far as the "primary color theory of visual color" is concerned, there are contradictions and unexplainable phenomena. Therefore, there is another school of color vision theory-Hering's "opposite color theory". As for the "opposite color theory" will be discussed and explained in the next article. 4. Opposite color theory In the previous article, we made a detailed discussion on the color vision theory of "the three primary colors of visual color", and then we will continue to study the "opposition color color theory". In 1878, the German physiologist Ewald observed that according to psychophysical research, red-green, yellow-blue, and black-white always exhibited a color phenomenon of opposite relationship; that is to say, red and green Blue, black and white cannot exist in any color sense at the same time. Therefore, Hering proposed the "Opponent Colors Theory" (Opponent Colors Theory or Opponenyt Process Theory). He assumes that the photoreceptor cells in the visual mechanism have the above three kinds of reactions of opposite colors. According to the above assumptions, it can be known that the Hering theory claims: "The color space belongs to the three-dimensional space, which are three bipolar coordinate axes of red-green, yellow-blue, black-white, etc. The combination of reaction effects produces various color perceptions and various color mixing phenomena. " Therefore, Hering's "opposite color theory" is also called "four primary colors theory" because he believes that various color perception phenomena are formed by four colors of red, green, yellow, and blue. Hering's "opposing color theory" put forward the following facts and phenomena: 1. Complementary color afterimage: This phenomenon is because when a color thorn stops, the opposite color related to the color will start to act, thus producing the opposite color of the color-complementary color. 2. Simultaneous contrast: When the retinal is undergoing a stimulus response to a pair of opposing colors, its adjacent parts will produce simultaneous contrast. 3. Color blindness: Because color blindness is caused by a certain pair of human eyes (red-green or yellow-blue) or two pairs of opposite color reaction processes, color blindness often occurs in pairs, that is, color blindness is usually It is red-green blindness or yellow-blue blindness, and when the reaction process of the two pairs of opposite color reaction cannot proceed, the phenomenon of total color blindness occurs. Color blindness. Nevertheless, Hering's doctrine has its shortcomings, that is, the phenomenon that the three primary colors of red, green, and blue can produce all spectral colors cannot be satisfactorily explained. But in any case, the opposite color theory mentioned by Hering is a very important theory in the chromatic theory in recent years. The most obvious example is that CIE Lab, Luv and other color space coordinates are all the opposite colors proposed by Hering. , Red-green, yellow-blue, black-white three coordinates, so Hering's color vision theory is also a very important basic theory for modern colorimetry. V. Stage visual color theory The stage vision color theory was first proposed by GE Muller (1930) and Judd (1949). They believe that for a long time, the color vision theory (Color Vision Theory) has been in a state of opposition to the three primary color theory and the opposite color color theory. Experimental studies have confirmed that the two can be integrated and coordinated, and a more complete explanation and explanation of the phenomenon of human color vision. But how does the stage visual color theory integrate the four opposite color metabolic reaction processes of the "opposite color theory" with the "primary color theory of visual colors"? Let me discuss it below. When light enters the retina of the human eye, the photo pigments in the cone cells selectively absorb radiation of different wavelength spectrum, and each cone cell can independently produce lightness according to the amount of light stimulation ( Black or white) and color (red, green, blue). In this stage, Young-Helmholtz's theory of three primary colors of visual color and color-light mixing experiment can be used to explain the phenomenon of visual color. Since the cone cells are connected to the optic nerve cells, the nerve impulses caused by the cone cells after being stimulated by light will form visual color signals again. (1) Neutral color signal (achromatic signal)-responsible for the integration of the lightness signal, receiving the photopic achromatic signal formed by three cone cells. (2) Color signal (chromatic signal) —— Responsible for the integration of color signal, receiving three cone cells. The formed red, green, and blue color signals; at this stage, the color signals are represented by the following three color difference signals: C1 = RG; C2 = GB; C3 = BR (R, G, and B represent three types respectively) Signals produced by cone cells). When these three color-difference signals C1, C2, and C3 are transmitted to the nerve center through nerve fibers, two color signals are generated and integrated, which are C1 and C3-C2. So at this stage, three pairs of opposite-colored nerve impulse responses are formed, and their signals are as follows: (1) Brightness signal ...... The opposite of black and white (2) Color signal C1 ............ The opposite colors of red and green (3) Color signals C3-C2 ............ The opposite colors of yellow and blue While the cone-shaped cells receive light stimulus and transmit it to the nerve center, the three pairs of opposite-colored nerve impulses respond exactly to Hering's opposite-colored color theory. If we put the above text description in the following figure, we can clearly understand how the order visual color theory integrates two visual color theories to produce color vision phenomena. Dining Chair,Dining Room Chairs,Dining Room Table Sets,Leather Dining Chairs Foshan Poesy Furniture Co., LTD. , https://www.poesy-furniture.com