English: Internal components of an old 1998 InFocus LP425z single-chip DLP projector, with a 4-segment color wheel.

Front section shows high-pressure metal halide lamp, color wheel (under round shroud), rear optics assembly containing the DMD, and zoom/focus lens.

In the rear, the bottom portion is the power supply for the lamp and electronics, the large circuit board is the video signal input and processing, the small board on top-left is the user interface for the menu buttons, and the small board on the top-right is the interface to the DMD and color wheel. Off to the left is the lamp cage and temperature sensor.