The present invention relates to a method for operating a rotation sensor for detecting a plurality of rates of rotation about orthogonal axes. The plurality of macular-pigment measurement machines include a device for receiving macular pigment data from a patient, at least one data transfer port, and at least one processor that enables the transfer of the macular pigment data from the transfer port. Based on the characteristic, a test string is generated for use as an input into the field defined in the user interface to perform validation on the field. The resonant frequency of the resonant circuit is variable in response to a sensed parameter such as, for example, the position of a head-rest of the seat, the inclination of the back-rest of the seat and such like. The device will be lightweight and extremely portable. The compressible portion of the receiving swab is located inside the casing, wherein by compressing the compressible portion, the transfer path is closable towards the outside of the device.