Fixing mechanism for an optical element comprising first and second fixing rods and projection device

A projection device, comprising a light source, an optical engine module and a projection lens, wherein

• the light source is configured to provide an illumination beam;
• the optical engine module comprises a housing, an optical element, a fixing mechanism, a light-homogenizing element and a light valve, wherein
• the fixing mechanism is arranged in the housing and is configured to fix the optical element, and the fixing mechanism comprises a first fixing rod and a second fixing rod, wherein
• the first fixing rod has a first sidewall and forms a first groove, the first sidewall is connected to a first extending portion protruding outward from the first sidewall and a first abutting portion, the first groove is located beside the first extending portion, and the first extending portion is connected between the first sidewall and the first abutting portion;
• and
• the second fixing rod has a second sidewall and forms a second groove, the second groove faces the first groove, wherein a first end of the optical element is accommodated in the first groove, a second end of the optical element is accommodated in the second groove, and the first abutting portion abuts against the optical element thereby fixing the optical element in the fixing mechanism;
• wherein the first fixing rod further has a first top surface and a first bottom surface, the first sidewall is connected to the first top surface and the first bottom surface, and the first groove extends from the first top surface toward the first bottom surface, wherein the second fixing rod further has a second top surface and a second bottom surface, the second sidewall is connected to the second top surface and the second bottom surface, and the second groove extends from the second top surface toward the second bottom surface;
• the light-homogenizing element is located on a transmission path of the illumination beam and is configured to transmit the illumination beam to the light valve;
• and
• the light valve is arranged in the housing and located on the transmission path of the illumination beam and is configured to convert the illumination beam into an image beam;
• and
• the projection lens is arranged in the housing and located on a transmission path of the image beam and is configured to project the image beam out of the projection device,
• wherein the optical element is arranged on the transmission path of the illumination beam or the transmission path of the image beam.

A fixing mechanism configured to fix an optical element, the fixing mechanism comprising a first fixing rod and a second fixing rod, wherein

• the first fixing rod has a first sidewall and forms a first groove, the first sidewall is connected to a first extending portion protruding outward from the first sidewall and a first abutting portion, the first groove is located beside the first extending portion, and the first extending portion is connected between the first sidewall and the first abutting portion;
• and
• the second fixing rod has a second sidewall and forms a second groove, the second groove faces the first groove, wherein a first end of the optical element is accommodated in the first groove, a second end of the optical element is accommodated in the second groove, and the first abutting portion abuts against the optical element thereby fixing the optical element in the fixing mechanism;
• wherein the first abutting portion comprises a bump structure, and the bump structure protrudes from the first extending portion toward the optical element;
• wherein the first groove has a first side surface and a second side surface opposite to each other, the first extending portion is adjacent to the first side surface, and a shortest distance from a top of the bump structure to a plane extending from the second side surface is smaller than a distance from the first side surface to the second side surface.