Abstract: An illuminator for photodynamic therapy includes a bulb, a condenser lens assembly and a filter assembly. The filter assembly includes the following components in an optical path: (1) a high-pass filter to filter out light having wavelengths below a first wavelength value; (2) a low-pass dichroic filter to filter out light having wavelengths above a second wavelength value; and (3) a dichroic mirror which reflects light having wavelengths between the first wavelength value and the second wavelength value and which transmits infrared light. An exit lens assembly directs light transmitted through the high-pass filter and the low-pass dichroic filter and reflected by the dichroic mirror onto a patient for photodynamic therapy. The condenser lens assembly and the exit lens assembly scramble the beam to ensure that the patient is illuminated with light which is highly uniform in both intensity and spectral characteristics (color) throughout the illuminated area.

Abstract: An anti-fouling system for producing vibrations in an underwater structure to inhibit the attachment of aquatic life forms to the structure. The system includes a controller which drives one or more transducer. The transducer comprises a housing, one end of which is closed by a resilient diaphragm. An electromagnet with soft magnetic core is contained in the housing spaced from an unsupported portion of the diaphragm. The unsupported portion of the diaphragm is mounted over an underwater structure. In operation, the electromagnet is excited with a current pulse, which deforms the diaphragm so that the housing moves towards the structure. As the current drops off, the diaphragm is restored to its original shape and the housing moves away from the structure imparting a vibrational force to the structure. The transducer includes an elastic membrane to compensate for changes in temperature and pressure commonly found when working under water.

Abstract: An illuminator for photodynamic therapy includes a bulb, a condenser lens assembly and a filter assembly. The filter assembly includes the following components in an optical path: (1) a high-pass filter to filter out light having wavelengths below a first wavelength value; (2) a low-pass dichroic filter to filter out light having wavelengths above a second wavelength value; and (3) a dichroic mirror which reflects light having wavelengths between the first wavelength value and the second wavelength value and which transmits infrared light. An exit lens assembly directs light transmitted through the high-pass filter and the low-pass dichroic filter and reflected by the dichroic mirror onto a patient for photodynamic therapy. The condenser lens assembly and the exit lens assembly scramble the beam to ensure that the patient is illuminated with light which is highly uniform in both intensity and spectral characteristics (color) throughout the illuminated area.