The tanning devices here may not be perceived as light therapy devices, but the concept of sun bathing morphed from scientific and quasi scientific light treatments at the end of the 19th century, where people would immerse themselves in light baths - hence the term sun bathing.Abuse of sun bathing as recreation has created a backlash, masking its genuine benefits in moderation and how it is perceived has obviously changed over time, as witnessed by my favorite item here which shows four congressmen in suits bathing in the light shower baths of the Turkish baths of the House of Representatives.