Patent ID: 7857465

Claim:
A light tunnel apparatus of an optical engine, the optical engine comprising a body, the light tunnel apparatus comprising: a light tunnel having a central axis; a housing connecting to the body; a frame, connected to the housing, the light tunnel being disposed in the frame; a positioning device, disposed between the frame and the housing, for providing at least a thrust, substantially perpendicular to the central axis, whereby allowing the frame to be restricted to move along an axial direction substantially parallel to the central axis; and an adjustment fixture comprising: a push block, detachably engaged with the frame; a push block frame for enclosing an outer portion of the push block, the push block frame being detachably engaged with the body; and a screw, disposed parallel to the central axis, the screw being threaded between the push block and the push block frame; wherein when the screw is rotated, the push block is driven to move in the axial direction relative to the push block.