A therapeutic light source, for example for photodynamic therapy, comprises an air-cooled array of LED’s, the air being vented in the vicinity of the array. One digital photography system of the present invention includes a first computing environment for initiating digital photography order requests. The input and output valves are selectively opened and closed to cause metered amounts of fluid to be dispensed from the metering device through the output valves. The present invention provides a water-insoluble xanthene coloring compound having a specific structure. A loosening amount of the hanging strap and the tether becomes largest when an occupant contacts the center portion of the front panel to retreat, and an opening amount of the open-and-close venthole also becomes largest.