The technology provides a camera module cover that prevents infrared light from leaking into the lens of an adjacent camera. The camera module cover can be used with in-vehicle environments, such as the passenger area and truck, as well as other indoor locations and places where infrared illumination is co-located with an optical camera system. An infrared illuminator unit is positioned adjacent to the camera, for instance in such a way that infrared light is evenly distributed or diffused around the camera lens. The camera module cover has a surface that includes an infrared-transparent material to promote even distribution of the infrared light. To avoid leakage into the camera lens, an infrared-opaque or otherwise blocking material is disposed within the cover so as to be between the infrared illuminator unit and the camera lens. The infrared-transparent and infrared-blocking materials may be formed as a single part via double injection molding.