System and method for continuous monitoring of a human foot

A device for monitoring feet of a human patient, said device comprising:

• a transmissive sheet configured to accommodate soles of said feet and to bear a load of at least 90 kg;
• a first optical sensor positioned no more than 23 cm below said transmissive sheet;
• a first diffuse optical light source;
• a second light source, wherein light emitted from said second light source is totally internally reflected within said transmissive sheet without contact by said feet and wherein contact of said feet on said transmissive sheet causes said light from said second light source to be reflected out of said transmissive sheet toward said first optical image sensor, wherein said second light source is coupled to a prism that is coupled to said transmissive sheet, wherein light emitted by said second light source is directed onto one side of said prism and wherein said prism directs said light from said second light source into said transmissive sheet;
• a central reflective element positioned under said transmissive sheet directly above said optical sensor;
• a first outer mirror below the transmissive sheet configured to reflect a first field of view of at least 250 cm2 from said transmissive sheet toward a first side of said central reflective element and onto one-half of said optical sensor;
• a second outer mirror below the transmissive sheet configured to reflect a second field of view of at least 250 cm2 from said transmissive sheet toward a second side of said central reflective element and onto the other half of said optical sensor so that said optical sensor simultaneously acquires said first field of view and said second field of view as a single image;
• a first lens coupled to said optical sensor configured to focus said first field of view and said second field of view reflected from said central reflective element onto said optical sensor;
• a third near infrared light source configured to emit light with a wavelength between 750 nm and 900 nm;
• and
• a second lens configured to focus light of at least two unique wavelengths, of which a first wavelength is between 390 nm and 710 nm and a second wavelength is between 750 nm and 900 nm, to a single focal plane.

A method for monitoring feet of a human patient, said method comprising:

• automatically capturing visible-light images of soles of said feet upon said patient standing on a transmissive sheet with an optical sensor located no more than 20 cm below said transmissive sheet, wherein said optical sensor is shielded against light that has undergone specular reflection due to reflection by said transmissive sheet rather than diffuse reflection due to reflection by said feet;
• automatically capturing total internal reflection (TIR) images of said soles upon patient standing on said transmissive sheet using TIR imaging;
• transmitting said visible-light images and said TIR images to a database accessible by a medical professional;
• comparing flat regions of said visible-light images and bright regions of said TIR images to identify pressure points on said feet and an error in capturing said visible-light images and said TIR images;
• associating said images of said soles with said patient in said database according to a predetermined characteristic;
• automatically capturing additional images with near-infrared light of said soles upon said patient standing on said transmissive sheet and
• transmitting said additional images to said database.

A device for monitoring a foot of a human patient, said device comprising:

• a transmissive sheet configured to bear a load of at least 90 kg with at least 250 cm2 of surface;
• a housing configured to support said transmissive sheet at a height of no more than 23 cm above a bottom of the housing and to bear said load of at least 90 kg;
• a foot image capture system positioned below said transmissive sheet and within said housing, having a first diffuse optical light source and a first optical image sensor and configured to capture a field of view including at least 250 cm2 of surface of said transmissive sheet;
• a second light source, wherein light emitted from said second light source is totally internally reflected within said transmissive sheet without contact by said foot and wherein contact of said foot on said transmissive sheet causes said light from said second light source to be reflected out of said transmissive sheet toward said first optical image sensor;
• a first polarizer positioned to polarize light emitted from said first diffuse optical light source;
• a second polarizer positioned in front of said first optical image sensor, wherein said first polarizer creates a first type of polarization and said second polarizer creates a second type of polarization that cancels light that has undergone specular reflection due to reflection by said transmissive sheet rather than diffuse reflection due to reflection by said foot and
• an air flow system configured to generate a flow of air across said transmissive sheet and remove moisture from said transmissive sheet.