Position adjustment device for integration rod

A position adjustment device for an integration rod, the integration rod being accommodated in an accommodation space defined by at least a part of a housing of an optical engine, the position adjustment device comprising:

• a first resilient member positioned between the part of the housing of the optical engine and the integration rod for exerting an elastic force on the integration rod in a first direction;
• a second resilient member positioned between the part of the housing of the optical engine and the integration rod for exerting an elastic force on the integration rod in a second direction substantially perpendicular to the first direction;
• a first adjusting screw inserted through the part of the housing of the optical engine and comprising a first end surface pressing against one side surface of the integration rod opposite the first resilient member, and
• a second adjusting screw inserted through the part of the housing of the optical engine and comprising a second end surface pressing against one side surface of the integration rod opposite the second resilient member,
• wherein each of the first end surface and the second end surface is a substantially arc surface to provide point contact between each of the first adjusting screw and the second adjusting screw and the integration rod.