In every country, there are many modern buildings with large, bright windows. For example, the building in our postcard is the pharmaceutical science building in UBC (the University of British Columbia). In our work, we impose the idea of solar windows which transfer UA radiation and infrared into energy (electricity) without the loss of visible light. This is to say, solar windows conserve the functions of windows, and they also make good use of the other components of light through windows. If we can have solar windows, a great amount of energy produced by them is used to energy supply, such as appliances, laptop, and illumination. Therefore, solar windows will have significant contributions to energy supply and sustainability of buildings.