Abstract: An optical system affixed to an electronic apparatus is provided, including a first optical module, a second optical module, and a third optical module. The first optical module is configured to adjust the moving direction of a first light from a first moving direction to a second moving direction, wherein the first moving direction is not parallel to the second moving direction. The second optical module is configured to receive the first light moving in the second moving direction. The first light reaches the third optical module via the first optical module and the second optical module in sequence. The third optical module includes a first photoelectric converter configured to transform the first light into a first image signal.

Abstract: Techniques for color change of Information elements (IEs) are described. In an example, a color of the IE and a color of a region of a virtual environment surrounding the IE may be compared. Based on the comparison, it may be determined whether the IE is distinguishable from the region of the virtual environment. Further, based on the determination, the color of the IE may be changed to facilitate distinguishability of the IE.