Applying colour science in colour design

Although colour science has been widely used in a variety of industries over the years, it has not been fully explored in the field of product design. This paper will initially introduce the three main application fields of colour science: colour specification, colour-difference evaluation and colour appearance modelling. By integrating these advanced colour technologies together with modern colour imaging devices such as display, camera, scanner and printer, some computer systems have been recently developed to assist designers for designing colour palettes through colour selection by means of a number of widely used colour order systems, for creating harmonised colour schemes via a categorical colour system, for generating emotion colours using various colour emotional scales and for facilitating colour naming via a colour-name library. All systems are also capable of providing accurate colour representation on displays and output to different imaging devices such as printers.     

Practical colour management

Spectrophotometers have been successfully used for colour measurement. This paper addresses digital imaging as a complementary and alternative method of colour measurement and appearance and an effective communication tool as part of a practical colour management programme within the supply chain of a textile retailer. The specific needs—to measure and communicate textured dyed material and printed fabric—are discussed, as well as the colour specification and quality control (QC) of currently un-measurable fabrics and accessories. A unique method of using digital imaging for the assessment of colour fastness will also be discussed.     

Detection of coloured tracks of heavy ion particles using photographic colour film

A photographic colour film, which was exposed to heavy ions, reveals a coloured dye image of the ion tracks. Since the colour film consists of several layers and different colours appear on each layer, three-dimensional information on the tracks in the layers can be obtained by the colour image. Previously, we have reported the method for which the tracks in different colours represented differences of track depth and we also discussed the disadvantages of using commercial colour films. Here we present the procedure for a self-made photographic coating and the development formula which can overcome the disadvantages.     

Then and now: James Clerk Maxwell and colour

A survey of the researches of James Clerk Maxwell into the production and perception of colour is presented, and links to a selection of present day applications of colour science are indicated. Although false colour photography was not known in Maxwell's time, aspects of his work, suitably interpreted, have a bearing on the wide applicability of the technique. An outline is given of one application of false colour to visualising and analysing data on fluid motion.     

The colour of domestication and the designer chicken

Colour is an important feature of most living organisms. In the wild, colour has great significance affecting the survival and reproductive success of the species. The environmental constraints which lead to the specific colours of birds and animals are very strong and individuals of novel colours tend not to survive. Under domestication, mankind has transformed all the species involved which have thus been freed from environmental pressures to a large extent. Early colour variants were mostly selected for utility reasons or religious practices. In more recent centuries colour varieties have been created purely for ornament and pleasure, fashion playing a surprisingly large part in their development. A bewildering array of colours and patterns can now be found in all our commensal species, especially the Domestic Fowl (Gallus gallus domesticus).     

Analytical model of phototherapy for neonatal jaundice. Influence of bilirubin kinetics on skin colour during phototherapy

Summary Recent progress in diode-array detector technology and signal processing methods, and in the optical modelling of tissues allow: i) real-time, multispectral analysis of reflected spectra with relatively simple and compact devices; and ii) improved correlations between reflectance spectra and pigment distribution in tissues. Second-generation transcutaneous bilirubinometers relying on the changes in the optical properties of the skin at selected wavelengths due to changes in its optical components are being developed. To extend the use of transcutaneous bilirubinometry to the phototherapy cycle, the modelling of the complex mechanisms of bilirubin photochemistry and metabolism in the various body compartments is required. As a first step toward this aim, the influence of bilirubin photochemistry occurring during the initial stage of phototherapy on the reflectance spectrum of an icteric tissue is analysed. A four-layer model is assumed. The transformation of bilirubin into its configurational isomers is considered in detail, while the role of the structural isomer on bilirubin elimination is taken into account with a loss term in the equation of motion of bilirubin concentration. The phototherapeutic process makes the illumination in the bile pigment layer depend on time. However, in the specific cases here considered, this time variation is negligible, and the differential equations describing the time evolution of bile pigment concentrations can be solved in a closed form. The bilirubin kinetics produces significant changes of the diffuse reflectance spectra during phototherapy, and the difference of the colour after the phototherapeutic treatment of a known duration can be put in close correspondence with the model of the jaundiced skin and permits quantitative estimates of pigment concentrations.     

Two international colour meetings

Two international Colour meetings held in May 1961 have given an opportunity or scientists working in this field to meet and compare notes. The first was the Maxwell Colour Centenary in London, organized by the Colour Group, with the Institute of Physics and Physical Society, and the Jnter–Society Colour Council (of the U.S.A.), to celebrate the first demonstration of colour photography; it was deliberately kept informal as its primary purpose was an Anglo–American get-together, and its twenty–odd invited papers consisted mostly of reviews of progress in the field over the last hundred years. The second meeting was on a larger scale, held in Dusseldorf, and organized jointly by the Fachnormenausschuss Farbe im Deutschen Normenausschuss (FNF) and the Centre d'Jnformation de la Couleur (C.I.C.) of France, being the fifth in a series of JournCes Jnternationales de la Couleur. More than eighty papers covered a range of topics from colorimetry and colour vision to problems of education and the use of colour in fashion, decoration, and advertising.     

Scanning of skin gloss by a diffractive optical element-based handheld glossmeter

Skin specular gloss (referred to as “gloss’’) determination is important in dermatology and cosmetic industry as it gives an indication of the skin health and beauty. Its accurate determination is, therefore, necessary. Commercially available glossmeters typically employ large incidence angle geometry, large illumination area, and fixed point measurements making them impractical regarding measurement of curved and complex non-planar objects or surfaces as well as low gloss regime such as the skin. In this study, we have demonstrated the novel application of a diffractive optical element-based handheld glossmeter with scanning capability, overcoming the disadvantages of conventional glossmeters, in the accurate determination of skin gloss and gloss profile for different skin types under different measurement conditions. Different parts of the body (back of the hands, the inner part of the arm and the forehead) of four volunteers with light, dark and intermediate skin types were scanned (also in different directions) to obtain the skin gloss profile and the statistical average skin gloss. Additionally, the skin surface was modified by arm extension and scanned as well. Our preliminary results showed that the statistical average skin gloss reading increased with the increasing lightness of skin. Areas with higher sebaceous glands (forehead) showed higher gloss reading than the other body parts (inner arm and back of the hand). However, the roughness of the skin surface decreased the statistical average skin gloss reading. The handheld scanning skin glossmeter allows for the accurate determination of skin gloss with sensitivity to small variation in the skin surface roughness with high repeatability.     

Seeing in colour

Understanding perception of colour is challenging because what we see is not always what is there, which is a phenomenon we call illusions. Here we review the nature of colour vision, and the problems facing most current models and explanations. Focusing on our recent research on humans, bees and computers, we describe a new, more ecologically based explanation that provides a clear framework for why we see what we do.     

The physics of colour vision

Investigation of human colour vision relies primarily upon psycho-physical methods which require active observer participation in the experiments. The principal results of such experiments are stated and discussed in relation to the functional organisation of human colour vision. Generally, objective techniques, such as electro-physiology, are employed in the study of colour vision responses in non-human vertebrate species. The structural and functional organisation of vertebrate colour vision as revealed by these objective methods is described and the relationship between objective and psycho-physical results examined. Other sections of the article are concerned with defective colour vision and with parametric variations in normal colour vision. It is concluded that a reasonably consistent scheme for the organization of human colour vision emerges from the various types of experimental investigation, and that this scheme is adequate for the interpretation of a variety of colour vision phenomena.     

二维彩色彩虹像面全息图记录的一种新方法

本文提出了利用液晶光阀和单色激光进行彩色全息图记录的方法.借助于液晶光阀非相干-相干转换的功能,采用新的彩虹全息术,获得了记录于同一块干版上的原彩色目标由红、绿、篮三色所成的三个基色彩虹全息像.用白光透射再现,得到原彩色图的真彩色全息像.这种方法是液晶光阀、条形散斑屏在图像处理中的一种特殊应用.     

On a predictive scheme for colour image quantization

In this paper we proposed an improved colour image quantization scheme based on predictive coding. Since the neighbouring colour pixels are quite similar in most colour images, the similarity among the encoded pixels is exploited. In the proposed scheme the encoded distinct neighbouring colours are collected to form a smaller state-palette. If the closest colour in the state-palette is quite similar to the current encoding colour pixel, the index of the closest colour in the state-palette is recorded. Otherwise, the closest colour in original colour palette for the current encoding colour pixel is searched and the corresponding index is recorded. The experimental results show that the proposed method achieves good image qualities while requiring much lower bit rates for colour image compression.     

The colour wheels of art, perception, science and physiology

Colour is not the domain of any one discipline be it art, philosophy, psychology or science. Each discipline has its own colour wheel and this presentation examines the origins and philosophies behind the colour circles of Art, Perception, Science and Physiology (after image) with reference to Aristotle, Robert Boyle, Leonardo da Vinci, Goethe, Ewald Hering and Albert Munsell.The paper analyses and discusses the differences between the four colour wheels using the Natural Colour System® notation as the reference for hue (the position of colours within each of the colour wheels). Examination of the colour wheels shows the dominance of blue in the wheels of art, science and physiology particularly at the expense of green.This paper does not consider the three-dimensionality of colour space its goal was to review the hue of a colour with regard to its position on the respective colour wheels.     

用模糊算子法对用通俗语言描述的颜色标志的定量评价

本文在确定颜色模糊性的基础上,用模糊算子的方法分析了用通俗语言描述的颜色标志,提出了一种颜色标志的定量方法。     

Plants and colour: Flowers and pollination

While there is a range of colours found in plants the predominant colour is green. Pigments in plants have several roles e.g. photosynthesis and signalling. If colour is to be used as a signal then it must stand out from green. However, one should be aware that there are also coloured compounds where we have not yet fully investigated the role of colour in their functions—they may have roles in, for example, defence or heat exchange.In this paper, we will describe the basic chemistry of the major pigments found in plants and especially floral pigments. We will then discuss their locations in parts of the flower (such as sepals, petals, pollen and nectar), the cells in which they are found and their sub-cellular locations.Floral pigments have a large role to play in pollination of flowers by animals. They can and are modified in many ways during the development of flowers in nature, for example, at emergence and post-pollination. There are a range of biochemical mechanisms of colour change both within flowers and in isolated pigments. Some of the factors influencing colour are temperature, co-pigments, pH, metals, sugars, anthocyanin stacking and cell shape.There is a renewed interest in analysing floral pigments and how they are modified partly because of advances in recombinant DNA technologies, but also because of pollinators and their significance to biodiversity and for evolutionary studies. There is continued strong interest from the horticultural industry for the introduction of new colours e.g. the blue rose and for the exploitation of natural dyes. Funding in this area may impact future research in a potentially beneficial way but it must not deflect us from science-based conservation.     

植物油颜色的谱识别方法

本文提出一种植物油色的谱识别新方法.该方法突破了传统的三刺激值测色模式,提出了用光谱特征及非固定的场景模式,替代三刺激值及其固定的CIE测量模式,建立了良好的判别函数,适于植物油色的客观检验与定级.结果令人满意.     

Spectral imaging system for non-contact colour measurement

This paper describes the development of a non-contact system for measuring colour of printed material at web speeds. The system proposed uses a non-contact spectrophotometer based on a holographic grating, in conjunction with a conventional monochrome area scan camera, from which colour spectral data is extracted, whilst a xenon flash is used to illuminate colour samples. Software and hardware details of the system are given, along with the underlying mathematics for colour space conversion and measurement. Conversion equations from X, Y, Z chromaticity co-ordinates to the RGB system are presented, and also equations to convert from the L^*a^*b^* colour space to X, Y, Z chromaticity co-ordinates. Experimental results are presented whereby the non-contact spectral system is shown to perform to a colour tolerance exceeding that of conventional colour video systems.     

Evaluation of temporal scales of migration of cosmetic ingredients into the human skin by two-dimensional dynamic speckle analysis

A variety of biomedical and food quality assessment tasks have been solved by statistical processing of speckle patterns formed on the surface of diffusely reflecting objects. The output of pointwise processing of a temporal sequence of correlated speckle images is a two-dimensional spatial contour map which characterizes the time scales of the ongoing physical or biological activity within the studied objects. In this work, we check efficiency of the dynamic speckle analysis for temporal characterization of migration of cosmetic ingredients from the skin surface to the lower skin layers. At illumination with a He–Ne laser, formation of speckle patterns on the skin surface is governed by the diffusely reflected photons which have undergone a lot of scattering events in the bulk of the tissue. This entails low time-correlation of the formed speckle patterns. Activity maps have been built for sections of treated and non-treated skin on the arm of a volunteer. We found out that a bare skin exhibited high activity which decreased for a skin treated by a cream or cosmetic oil. We proved that the observed difference between the activity maps for a bare skin and a treated skin would allow for monitoring of the time scales of penetration of various cosmetic products into the skin to perform their quality assessment.     

The nature of sound and vision in relation to colour

The increasing role of sound within the visual arts context and the trend in postmodernism towards interdisciplinary artworks has demanded a heightened awareness of the audio-visual. This paper explores some of the fundamental physical properties of both sound and colour, their similarities and differences and how the audio and visual senses are related. Ways in which soundscapes have been combined with paintings in exhibitions by the author will be used to illustrate how the two media can be combined to enhance the overall artistic experience.