Apparatus is provided, including an external device, including a mount, which is placed in front of an eye of a subject. A laser is coupled to the mount and configured to emit toward the eye radiation that is outside of 380-750 nm. A partially-transparent mirror is coupled to the mount. An intraocular device is implanted entirely in the subjects eye, and includes a plurality of stimulating electrodes, and an energy receiver, which receives the radiation from the laser and generates a voltage drop in response thereto. A plurality of photosensors detect photons and generate a signal in response thereto. Driving circuitry is coupled to the energy receiver and to the photosensors, and receives the signals from the photosensors and utilizes the voltage drop to drive the electrodes to apply currents to the retina in response to the signals from the photosensors. Other embodiments are also described.