This wikipedia article concerning focal-plane shutters opens with the following statement (bold emphasis added by myself):
In camera design, a focal-plane shutter (FPS) is a type of photographic shutter that is positioned immediately in front of the focal plane of the camera, that is, right in front of the photographic film or image sensor.
Other references concerned with photography almost universally seem to equate focal plane and film plane. This statement is from the wikipedia article concerning focal length (bold emphasis added by myself):
When a photographic lens is set to "infinity", its rear nodal point is separated from the sensor or film, at the focal plane, by the lens's focal length. Objects far away from the camera then produce sharp images on the sensor or film, which is also at the image plane.
In both of these references the meaning of focal plane and image plane appear to be interchangeable when the distance from the lens' rear nodal point to the film/sensor plane is equal to the lens' focal length.
Yet in physics references that discuss the field of optics (such as this wikipedia article linked from the article cited above) the focal plane is defined differently. It seems the front focus plane is defined as what photography refers to as the plane of focus. The back focus plane seems to be defined as the point behind the lens where the aperture is ideally situated. Yet the charts and diagrams on the same page seem at times to use the terms rear focal plane, back focal plane, and image plane interchangeably. Sometimes it seems they are referring to the plane where the image is brought into focus (such as this diagram and the text beneath it in the article). At other times it seems to be referring to the crossover point between the lens and the image plane (such as this diagram and the text next to it in the article).
When speaking in the context of Photography that uses film or a digital sensor to record an image projected onto that film or image sensor is it legitimate to refer to the film or sensor as occupying the Focal Plane? Is there a nomenclature that allows one to distinguish between the plane occupied by the objects depicted as in focus in the image (plane of focus?, front focal plane?) and the plane the in-focus image is projected on (rear focal plane)?