Abstract: A dual-mode stereoscopic three-dimensional (3D) projection display with two micro-display panels is provided. In a passive 3D mode, the 3D projection display simultaneously projects left-eye and right-eye images with first and second polarizations on the screen. The first and second polarizations are orthogonal to each other. In a first passive mode, a polarization-preserving screen is used and passive polarizing glasses can be worn to see the 3D images. In a second passive mode, an ordinary screen is used and 3D color filter glasses can be worn to see the 3D images. In an active mode, the display projects left-eye and right-eye images, with both first and second polarizations, time-sequentially and liquid crystal shutter glasses synchronized with the image sources can be worn to see 3D images. The dual-mode 3D projection display can be switched electronically to project 2D images when the same 2D image signals are fed to both micro-display panels.