Abstract: A color wheel with a balancing groove comprises a carrier, having a central axis, a external surface, and a periphery, and rotates along the central axis; a set of filter plate sharing the same central axis with the carrier, wherein one or more annular groove is disposed on the external surface of the loading element, and a balancing substance is added into the annular groove to balance the color wheel.

Abstract: A color wheel with a balancing groove comprises a carrier, having a central axis, a external surface, and a periphery, and rotates along the central axis; a set of filter plate sharing the same central axis with the carrier, wherein one or more annular groove is disposed on the external surface of the loading element, and a balancing substance is added into the annular groove to balance the color wheel.

Abstract: A heat source shielding device for a hollow integration rod of a projecting apparatus wherein the hollow integration rod has an incident light end and an outgoing light end. The heat source shielding device has a heat source shielding mask that is an integrally formed metal sheet structure used for slipping onto the incident light end of the hollow integration rod. And the heat source shielding mask consists of a first end, a second end. an end cover, a heat shielding plate, a first side plate, a second side plate, and a top plate. Heat accumulated by the heat shielding plate on the heat source shielding mask is dissipated by the use of the ventilation system in the projecting apparatus due to convection.