1. The concept change of light and space

richard rodgers, a famous British architect, said, "Architecture is a container to capture light, just like how musical instruments capture music, and light needs a building to display it." Indeed, light is the soul of architecture. Without light, vision is impossible. The form, color and texture of architectural formal elements rely on the energy of light, so that we can experience the changes of architecture in the four seasons and the differences between morning, afternoon and evening in a day. The architecture rendered by light and shadow improves the environmental quality, and we naturally dissolve into the artistic conception condensed by the interweaving of light and architecture.

The development of architectural design thinking has promoted people's understanding of light, and the role of light has increasingly shifted from outdoor to indoor and from function to spirit. The change of concept drives the progress of architectural design and makes the architectural level leap into a new level.

The thinking mode of classical architecture established by modeling means represents the ancient people's judgment standard on architecture, which has a profound historical origin and a broad cultural foundation and lasted until the birth of modernism at the beginning of last century. This kind of modeling focuses on the external formal elements of the building, such as reflecting the aesthetic consciousness of the building, such as the sense of volume, concave-convex changes and scale, and the use of light is mostly limited to outdoor modeling to highlight the three-dimensional effect of the building itself and the undulating effect of the building facade. Unfortunately, because outdoor light is natural light, people can't use it at will, which reflects the helplessness of architecture to light. With the rise of modernist architecture, architects have realized that the interior space of a building is the main body of the building, and the external form is the external manifestation of the mechanism of the interior space of the building. The focus of the building has shifted to the treatment of the interior space, and at the same time, the development of artificial light sources has been greatly promoted, and the indoor light environment has been developed unprecedentedly.

The light environment plays an important role in the interior. The definition of the interior space has developed from a closed state surrounded by faces to different levels of semi-opening and opening, in which light plays a unique role in creating space. Light creates space without physical enclosure, and shapes space by using various forms and colors of artificial light in addition to natural light, which opens up a new field of space properties. In the continuous spatial sequence, light also shows its potential. Because the concept of space has added the time factor, people no longer watch the space from a static angle, and architecture is no longer solidified music, but a flowing space sequence that can be experienced. Because light can limit the space and change the nature of the space, when creating a spatial sequence, by controlling the light and dark, big and small, virtual and real, strong and weak, the ups and downs of spatial connection can be achieved, and a composite indoor light spatial sequence can be formed. Light can't be compared with other means in focusing the visual focus and highlighting the core form. Visual focus can break the single visual phenomenon caused by spatial homogenization and prevent visual fatigue. Its means is to use the difference principle of visual perception to create grade deviation to strongly attract the attention of vision, and the light is focused on a certain point, thus reducing the measurement of other areas to achieve the purpose of highlighting, making the primary and secondary importance clear at a glance and strengthening the spatial focus. The use of light is functional at first. Once the light disappears, people lose the ability to understand the surrounding information. Darkness makes people fall into a state of out of control without support, and ignorance of the surrounding things and the unexpected events will lead to fear. People have an instinctive dependence on light. A bright light in the dark increases people's hope of survival, and the sunshine in winter brings warmth to people. In restaurants, offices or homes, people like to stay in front of the window. This is because they are eager for light. At night, people are willing to gather under the lights, which shows the preciousness of light.

due to the improvement and popularization of optical technology, the indoor light environment in modern architecture has a rich vocabulary. It develops to the spiritual level while providing ordinary functional lighting. It embodies the lighting connotation with artistic lighting means, promotes the personality characteristics of different indoor spaces, and makes the indoor space environment set off a distinct space atmosphere appropriately. When the indoor space completes its functional needs, it will eventually solve the emotional communication with people. This emotion is transformed into spatial personality perception through visual and physical experience. Different spaces give people different feelings and form specific spatial personality. Space design is the pursuit of spatial personality differences, the pursuit of specific spiritual needs, and the satisfaction of people's rich spatial psychological perception. Light has a touching charm, arouses free, rich and agile association, and through the unique means of expression such as strengthening, weakening, blurring and materialization of light, it renders a specific space atmosphere, shapes various spatial personalities, and makes the material existence of indoor space rise to the spiritual dimension. Space and light environment have a similar side, and both have the characteristics of embodying spirituality. The integration of space and light environment will enhance its spiritual content. American architect Louis Kahn profoundly revealed the relationship between them: "Design space is design light".

2. Means of expression of light environment and spatial character

Creating different spaces should have different expressions, which is determined by people's physiological and psychological needs. People should have the space support of corresponding atmosphere when engaging in various activities. If the space atmosphere and the nature of activities are misplaced, there will be various discomforts, which will hinder the smooth progress of activities. People's activities are multifaceted, and their spatial personality should be rich and colorful, so as to meet people's spatial positioning needs based on people. Indoor light environment and spatial character are so closely related, we should consciously experience the relationship between them when designing, accurately grasp the sense of proportion, make full use of light language and give full play to the expressive force of light elements, and create beautiful and pleasant indoor space.

2.1.1 Cheerful and enthusiastic spatial personality

In festivals, people get together to hold various celebrations or relax after work, providing a cheerful and cheerful space environment is an ideal place to solve people's problems in adjusting their emotions. In space design, dining space, entertainment space and commercial space have the potential to create a cheerful atmosphere, because in these spaces people can gather together to enjoy eating fun, or entertain emotionally and shop easily. In order to meet the needs of this theme, corresponding measures should be adopted in the design to obtain the required personality space. When dealing with light environment, the design idea is effectively expressed from the aspects of light source layout, shape and color. The layout of the light source should adopt a random way, naturally combine the light positions so as not to fall into rigidity, and deliberately achieve flexible and light visual effects. The shape of light source should be interspersed with irregular and arbitrary shapes to activate the space atmosphere. In terms of the color of the light source, bright warm colors should be given priority to, because warm colors remind people of sunshine and flames, which can easily cause emotional fluctuations and produce warm and cheerful emotions. Figure 1 is the design of the corridor light environment of a club. The ceiling adopts irregular lighting layout, which is ups and downs, scattered and scattered, in contrast to the lighting layout of the wall and the ground, showing a bit of leisure and serenity. The chandelier wrapped in fabric not only adds an active temperament to the shape, but also fills the whole space with moving warmth, which is coordinated with the orange lighting on the ground to make the up and down echoes. The blue-purple light from the wall is in contrast with the overall red, yellow and warm tones, which sets off a vivid and jumping color expression. When people walk into the corridor and are wrapped in the blazing atmosphere, they are bound to be full of infinite reverie and longing for the space sequence that is about to enter.

2.1.2. Serious and cold spatial personality

When people enter the working state, they hope to have a suitable environment. In interior design, scientific research, study, meetings and other activities with high thinking or research exchange nature, people are in a state of tension. This nature of work determines that the space must have a quiet and serious space atmosphere to avoid disorder, which should be visually rigorous and standardized, so that people can think carefully and deeply in such an environment. Good spatial environment plays a role in boosting work efficiency, and lighting design lays a solid foundation for realizing this spatial significance. From the analysis of light source situation, we should use the combination of natural light and artificial light to fully absorb natural light source. Artificial light is mainly direct lighting, and decorative lighting is reduced to avoid the visual burden of light source and enhance the visual realism on the premise of ensuring spatial brightness. The size and shape of the light source are as consistent as possible, forming a strict and uniform pattern.

the shape of the light source itself should not be changeable, and it is mainly regular linear and planar. The window surface is the source of natural light, so it is necessary to deliberately open large windows, whole windows and panes to form a planar light source. The artificial light is mainly linear to obtain uniform visual effect. The color of light source should simplify the vocabulary, control the five-color or slightly cool color as the main tone of space lighting, and bring the wall, ceiling, floor and furnishings into a unified color range, so as to obtain a clear and uniform visual space character. 1) Font design (2) Logo design (3) Illustration design (4) Arrangement design (5) Advertisement design (6) Packaging design