An array of blue-emitting LEDs centered at about 460 nm, with a gaussian distribution of plus-or-minus 20 nm. are housed in an elongated housing and powered from a standard USB cable or equivalent DC power source. The user can select between a higher and lower intensity. The blue wavelengths in this range are very effective for cirtopic receptors of the eye, with little impact upon visual receptors (i.e., rod cells and cone cells). This allows optimal therapeutic effect with minimal visual side effects.
