An in vivo image capturing system includes a capsule, and a camera encased within the capsule and configured to capture through a transparent window of the capsule, a view outside the capsule. The system includes a light source enclosed within the capsule and a reflector configured to reflect a ray of light from the light source, away from the camera. Wherever incoming image rays and outgoing illuminating light rays intersect at a common point on any surface of the transparent window, an angle between an outgoing illuminating light ray and a surface normal exceeds an angle between an incoming image ray and the surface normal such that a reflection of the outgoing illuminating light ray from said any surface is not within a field of view (FOV) of the camera.