The present disclosure relates to hair readers, dispenser devices, and related systems and methods. For example the present application relates to a method of optically acquiring data from keratinous fibers, the method comprising: a. illuminating the keratinous fibers such that light reflected and/or deflected and/or transmitted by the fibers is incident upon a detector and converted into electrical signals by the detector; and b. computing, from electrical signals, a plurality of spectra of the keratinous fibers such that each spectrum of the plurality of spectra respectively corresponds to (i) a different respective portion of the keratinous fibers and/or (ii) material within a different sub-region of space within which at least a portion of the keratinous fibers are disposed.