Electro-optical device encased in mounting case, projection display apparatus, and mounting case

An electro-optical apparatus, comprising:

• an electro-optical panel including:
• an image display region that receives light from an external source,
• a peripheral region at the periphery of the image display region,
• a side surface;
• a plate that opposes a surface of the electro-optical panel, the plate including a side portion extending in parallel and in opposition with the side surface of the electro-optical panel;
• a cover that, in cooperation with the plate, accommodates at least a portion of the peripheral region of the electro-optical panel, the cover including a side wall that opposes the side surface of the electro-optical panel, the side wall of the cover having an inner surface and an outer surface, the inner surface contacting the side portion of the plate and the outer surface including a plurality of fins at positions opposing the side portion of the plate.