in a film camera, or sensor, in a digital camera. (This diagram shows an image that's out of focus). A large Sensor makes a shallow depth of field You can use a camera with a large sensor to ...

You also have medium format and large format film cameras ... and cannot produce as shallow a depth of field. TLDR: there are many digital cameras and phones that cannot, all things being equal ...

This characteristic makes medium format film highly suitable for portraits, where you can focus on your subject's eyes and use depth of field to make that the focal point of your image.