A portable lamp, such as a headlamp, having control of the light power without the need for any manual switch is presented. The lamp comprisesa power module for powering one or more light sources,first proximity detectors for detecting an object such as a finger moving close to the lamp, in one direction or another along a first axis X-X; anda control module receiving information generated by said first proximity detectors, said control module being configured for generating, from the direction of the movement of said object, a control information for switching-on, switching-off or adjusting the level of the intensity of the light power.