Skin optical characterization device

Abstract

The present invention is generally directed to dermatological devices and methods in which one or more skin characteristics, such as the melanin index, are determined by analyzing radiation backscattered from a skin region illuminated by at least one, and preferably, two or more wavelengths, e.g., in a range of about 600 nm to about 900 nm. In many embodiments, the radiation is coupled to the skin via a waveguide, and an optical sensor is employed to ascertain contact between the waveguide (e.g., a waveguide surface adapted for contact with the skin) and the skin.

What is claimed is: 
     
         1 - 45 . (canceled) 
     
     
         46 . A dermatological device, comprising
 at least one radiation source,   a waveguide optically coupled to the radiation source to transmit radiation from the source to the skin, said waveguide having two opposed surfaces and a sidewall extending between said surfaces,   a detector coupled to the waveguide to detect at least a portion of radiation backscattered from a skin region illuminated by the source radiation, and an optical contact sensor optically coupled to said sidewall, said sensor determining whether said waveguide is in contact with the skin based on detection of backscattered radiation leaking through said sidewall.   
     
     
         47 . A dermatological device, comprising:
 a radiation source assembly;   a first waveguide having a proximal end adapted to receive radiation from the radiation source assembly and a distal end adapted to transmit radiation to a tissue;   a second waveguide having a distal end adapted to receive backscattered radiation from said first waveguide and a proximal end adapted to transmit said backscattered radiation;   a detector optically coupled to said second waveguide and configured to measure a physical characteristic of said tissue; and   a processor electrically coupled to the detector and configured to receive a signal from said detector corresponding to said backscattered radiation;   wherein said processor is configured to determine a physical characteristic of said tissue based on the backscattered radiation that is detected.   
     
     
         48 . The device of  claim 47 , wherein the device further comprises a means for coupling said backscattered radiation exiting from said proximal end to the detector. 
     
     
         49 . The device of  claim 48 , wherein said means comprises a beamsplitter. 
     
     
         50 . The device of  claim 47 , wherein the radiation source assembly is capable of generating radiation at two or more wavelengths in a range of about 350 nm to about 1200 nm. 
     
     
         51 . The device of  claim 47 , wherein the radiation source assembly is capable of generating radiation at two or more wavelengths in a range of about 600 nm to about 900 nm. 
     
     
         52 . The device of  claim 47 , wherein the first waveguide is an optical fiber. 
     
     
         53 . The device of  claim 47 , wherein the second waveguide is an optical fiber. 
     
     
         54 . The device of  claim 47 , further comprising additional waveguides. 
     
     
         55 . The device of  claim 54 , wherein said additional waveguides are optical fibers. 
     
     
         56 . A dermatological device, comprising
 at least one source of radiation,   an optical fiber receiving radiation from said source at a proximal end and applying the radiation to a skin region at a distal end,   another optical fiber coupled at a distal end to skin at another region separated from the illuminated region by a skin segment so as to receive at least a portion of the applied radiation after transmission through that segment,   a detector optically coupled to a proximal end of said another optical fiber to detect at least a portion of said transmitted radiation received by that fiber, said detector generating a signal indicative of an intensity of said received radiation, and   a processor operating on said detector signal to determining a skin characteristic.   
     
     
         57 . A method of determining a characteristic of tissue comprising:
 applying radiation of first and second wavelengths from a waveguide to said tissue;   detecting at least a portion of radiation of said first and second wavelengths backscattered from said tissue generating at least one signal indicative of an intensity of the backscattered radiation, and   processing said at least one signal to calculate a characteristic of the skin region.   
     
     
         58 . The method of  claim 57 , wherein the step of applying radiation further comprises applying radiation at a plurality of wavelengths selected from a range of about 350 nm to about 1200 nm. to the skin. 
     
     
         59 . The method of  claim 57 , wherein the step of applying radiation further comprises applying radiation at a plurality of wavelengths selected from a range of about 600 nm to about 900 nm. 
     
     
         60 . The method of  claim 57 , further comprising detecting optical contact between the waveguide and the skin region. 
     
     
         61 . The method of  claim 57 , further comprising sensing contact of said waveguide with said tissue by detecting a level of said backscattered radiation. 
     
     
         62 . The method of  claim 57 , further comprising reducing ambient radiation to prevent its detection by the detector. 
     
     
         63 . The method of  claim 57 , further comprising:
 reducing radiation having a first polarity prior to detection; and   detecting radiation having a second polarity.