Abstract: Two opposing fingers of a robot hand are each provided with an array of optical devices which are capable of being in optical communication with one another through the gap between the fingers. One finger is provided with an array of light emitters and the other is provided with an array of light recepetors. By taking advantage of the motion of the robot hand and the small size of the optical devices, the shape of an object between the fingers can be detected by using at least one linear set, and preferably at least two linear sets, of devices in each array. Illustratively, the linear sets form a T-shaped array or a U-shaped array and are disposed along the edges of the fingers. In one embodiment the emitters are GRIN rod lenses coupled through a fiber cable to a light source, and the receptors are also GRIN rod lenses coupled through a fiber cable to a camera system. A manufacturing method utilizing such a sensor to identify the shape of objects is also described.