Patent ID: 8323221

Claim:
A system for controlling an ultrasound energy emitter, the system comprising: a temperature indicating element configured to apply topically on skin of a mammalian body in a path between the ultrasound energy emitter and an area on the body to be exposed to the ultrasound waves, the element comprising a layer with a thickness ranging from 100 μm to 5 mm having one or more temperature indicating agents operating by changing an optical property, said layer comprising hydrogel transparent to ultrasound energy; a light source configured to irradiate the temperature indicating element, the irradiation generating a temperature indicating signal when laterally passing through the element; a light detector configured to detect the temperature indicating signal including temperature related information; and a controller connected to the light detector and the ultrasound energy emitter configured to adapt power output of the ultrasound energy emitter in accordance with the temperature related information.