The light emitted by a computer screen is typically linearly polarized. LCD (liquid crystal display) screens, which are commonly used in computers and other electronic devices, produce linearly polarized light. The orientation of the polarization may depend on the specific design and construction of the screen.
LCD screens consist of layers of liquid crystals sandwiched between two polarizing filters. These filters allow light waves that are polarized in a specific direction to pass through while blocking light waves polarized in other directions. By manipulating the alignment of the liquid crystals, the intensity and color of light passing through the filters can be controlled to produce the desired display.
However, it's important to note that the light emitted from a computer screen can interact with the surrounding environment and undergo various changes. Reflections, refractions, and scattering of light can alter its polarization state. Additionally, specialized screens or applications may use different technologies that can introduce circular polarization effects. However, for standard LCD computer screens, linear polarization is the typical mode of light emission.