We recommend starting at one hour, and after a couple of weeks, when the beneficial effects of the light therapy are fully realized, reducing the daily exposure time. Most people find they can shorten the time to 30 - 45 minutes, without a reduction in effect. The time when light therapy is most effective can vary with the individual.
Some people respond to either morning or evening exposure.
It is not necessary to look directly at the lamps as the photoreceptors for the non-visual pathway are spread throughout the retina. It is important, however, to look periodically in the direction of the lamp while reading in order to ensure that there is sufficient exposure of the retina to the light.