A system and method for contactless power transfer in a portable image detector for charging rechargeable batteries disposed within the portable image detector is provided. The system includes a first coil couplable to a power source, wherein the first coil is configured to produce a magnetic field. The system further includes a second coil coupled to the rechargeable battery disposed within the portable image detector and configured to receive power from the first coil via the magnetic field and to transfer the power to the rechargeable battery. The system also includes a field focusing element disposed between the first coil and the second coil and configured as a self resonant coil having a standing wave current distribution to focus the magnetic field onto the second coil and enhance the coupling between the first coil and the second coil.