Eye safe dermatological phototherapy

Method of aesthetic improvement, comprising:

• a) providing a source for generating intense pulsed light and a light propagation assembly by which said light is directed to a target;
• b) positioning the distal end of said propagation assembly at a first position in close proximity with said target;
• c) causing said source to generate at least one pulse of polychromatic light;
• d) diverging said pulsed light at a location between said source and said target, whereby at said first position the energy density of light exiting from said diverging location is substantially equal to the energy density of the intense pulsed light;
• and
• e) effecting an aesthetic improvement,
• wherein the radiance of the light emitted from said diverging location, at a second position distant from said target, is less than 10*k1*k2*(tˆ⅓) J/cm2/sr, where k2=1 and t is pulse duration of the intense pulsed light in seconds, k1=1 for a wavelength ranging from 400 to 700 nm, k1=1.3 for a wavelength of approximately 570 nm, k1=1.6 for a wavelength of approximately 830 nm, k1=3 for a wavelength of approximately 940 nm, and k1=5 for a wavelength greater than 1050 nm.

An eye safe handpiece, comprising:

• a) a handpiece body for transmitting intense pulsed light through a distal end of said body to a target, said distal end being positionable at a predetermined location substantially in contact with said target;
• b) light delivery means for delivering said light from an intense pulsed light source to said distal end;
• c) means for directing the light which is transmitted through said distal end to said target;
• and
• d) a diffusing unit attachable to said body, said diffusing unit including at least one diffuser that is transparent to said light wherein a diffusing surface of said diffuser is disposed internally to said handpiece body;
• wherein the energy density of the light exiting said distal end at said location ranges from 1 to 100 J/cm2,
• wherein the radiance of the light exiting said distal end at said location is less than 10*k1*k2*(tˆ⅓) J/cm2/sr, where t is a pulse duration of the intense pulsed light in seconds, k2=1, k1=1 for a wavelength ranging from 580 to 700 nm, k1=1.3 for a wavelength of approximately 570 nm, k1=1.6 for a wavelength of approximately 830 nm, k1=3 for a wavelength of approximately 940 nm, and k1=5 for a wavelength greater than 1050.

Method for effecting purpura-free and scar-free treatment of skin, comprising:

• a) attaching a diffusing unit to the distal end of a light propagation assembly of a laser or intense pulsed light source;
• b) positioning the distal end of said light propagation assembly at a predetermined location substantially in contact with a skin target;
• c) setting the wavelength and energy density of the light exiting the distal end at a level which is suitable for effecting a desired treatment of said skin target;
• d) firing the light source at said set wavelength and energy density level for a sufficient period of time to effect said treatment;
• and
• e) allowing said light to be completely scattered by means of said diffusing unit, whereby said treatment is effected without formation of purpura or scarring in the vicinity of said skin target.

Method of preventing the appearance of purpura or scarring during treatment of a desired skin target by a laser or intense pulsed light source, comprising:

• a) attaching a diffusing unit to the distal end of a light propagation assembly of a laser or intense pulsed light source;
• b) positioning the distal end of said light propagation assembly at a predetermined location substantially in contact with a skin target;
• and
• c) firing the light source, while allowing the light exiting said light propagation assembly to be completely scattered by means of said diffusing unit, whereby a desired treatment is effected without formation of purpura or scarring in the vicinity of said skin target.

Apparatus for effecting purpura-free and scar-free treatment of skin, comprising:

• a) a laser or intense pulsed light source;
• b) a light propagation assembly for directing light of said source and which is displaceable to a predetermined location substantially in contact with a skin target;
• c) a diffusing unit attachable to the distal end of said light propagation assembly, light exiting said light propagation assembly capable of being completely scattered by means of said diffusing unit;
• and
• d) means for setting the wavelength and energy density of the light exiting the distal end at a level which is suitable for effecting a desired treatment of said skin target without formation of purpura or scarring in the vicinity of said skin target, said completely scattered light preventing formation of purpura or scarring.