Polarized imaging apparatus for use with a mobile device

Abstract

Apparatus for obtaining polarized imagery using a portable device, comprising a light source, a first polarizing filter configured to cover the light source, a second polarizing filter configured to cover the lens of a mobile device's built-in camera, one or more housing to contain the light source and filters, and couplers attached to the housings for coupling the housings to the mobile device. When the housing is coupled to the mobile device and the camera is operated, light from the light source passes through the first polarizing filter, then passes as polarized light through an illuminating path to illuminate an object being imaged. Then light from the illuminated object passes through an optical path, through the second polarizing filter to the camera lens. In embodiments, the axis of polarization of at least one of the polarizing filters can be modified to allow for cross, parallel and variable polarized imaging.

1 . (canceled) 
     
     
         2 . An apparatus for obtaining polarized imagery of an object, the apparatus comprising:
 one or more first polarizing filters;   a second polarizing filter; and   a housing containing (i) a first polarizing filter of the one or more first polarizing filters and/or (ii) the second polarizing filter,   wherein:
 the apparatus is configured to be coupled to a mobile device separate from the apparatus, and 
 when the apparatus is coupled to the mobile device
 the first polarizing filter is positioned between a light source and the object such that first light emitted from the light source passes through the first polarizing filter and thereafter propagates as polarized light towards the object; and 
 the second polarizing filter is positioned over a lens of a camera built into the mobile device such that (a) second light from the object passes through the second polarizing filter to the lens and (b) the camera can capture a polarized image of a region of the object. 
 
   
     
     
         3 . The apparatus of  claim 2 , further comprising the light source. 
     
     
         4 . The apparatus of  claim 3  wherein the light source includes a plurality of illuminating elements. 
     
     
         5 . The apparatus of  claim 4  wherein:
 the plurality of illuminating elements includes a first illuminating element and a second illuminating element; and 
 the first illuminating element can be independently controlled from the second illuminating element. 
 
     
     
         6 . The apparatus of  claim 4  wherein:
 the plurality of illuminating elements includes a first illuminating element and a second illuminating element; 
 the first polarizing filter is positioned between the first illuminating element and the object when the apparatus is coupled to the mobile device; and 
 another first polarizing filter of the one or more first polarizing filters is positioned between the second illuminating element and the object when the apparatus is coupled to the mobile device. 
 
     
     
         7 . The apparatus of  claim 6  wherein:
 the first polarizing filter has a first axis of polarization; and 
 the other first polarizing filter has a second axis of polarization different from the first axis of polarization. 
 
     
     
         8 . The apparatus of  claim 4  wherein:
 the plurality of illuminating elements include a first illuminating element and a second illuminating element; 
 the first illuminating element is configured to emit light of a first spectrum; 
 the second illuminating element is configured to emit light of a second spectrum different from the first spectrum; 
 the first spectrum is a visible light spectrum, an ultraviolet light spectrum, or an infrared light spectrum; and 
 the second spectrum is the visible light spectrum, the ultraviolet light spectrum, or the infrared light spectrum. 
 
     
     
         9 . The apparatus of  claim 3  wherein an intensity or wavelength of the first light emitted from the light source is based, at least in part, on a measurement captured by a sensor. 
     
     
         10 . The apparatus of  claim 9  wherein the sensor is an optical photodiode. 
     
     
         11 . The apparatus of  claim 2  wherein the light source is built into the mobile device. 
     
     
         12 . The apparatus of  claim 2  wherein:
 an axis of polarization of at least one polarizing filter of the apparatus is fixed; and 
 the at least one polarizing filter includes one first polarizing filter of the one or more first polarizing filters or the second polarizing filter. 
 
     
     
         13 . The apparatus of  claim 2  wherein, when the apparatus is coupled to the mobile device, the second polarizing filter is adhered to the camera. 
     
     
         14 . The apparatus of  claim 2  wherein, when the apparatus is coupled to the mobile device, the first polarizing filter is adhered to the light source. 
     
     
         15 . The apparatus of  claim 2  wherein:
 the housing is a first housing containing the first polarizing filter; 
 the apparatus includes a second housing separate from the first housing; and 
 the second housing contains the second polarizing filter. 
 
     
     
         16 . The apparatus of  claim 2  wherein:
 an axis of polarization of at least one polarizing filter of the apparatus is arranged in the housing such that the axis of polarization can be altered; and 
 the at least one polarizing filter includes one first polarizing filter of the one or more first polarizing filters or the second polarizing filter. 
 
     
     
         17 . The apparatus of  claim 2  wherein:
 the camera is a first camera and the lens is a first lens; 
 the apparatus further includes a third polarizing filter; and 
 when the apparatus is coupled to the mobile device, the third polarizing filter is positioned over a second lens of a second camera built into the mobile device such that third light from the object passes through the third polarizing filter. 
 
     
     
         18 . A system for obtaining polarized imagery of an object, the system comprising:
 a mobile device including a camera;   a light source;   an apparatus removably coupled to the mobile device, the apparatus including a first polarizing filter; and   a second polarizing filter,   wherein:
 the first polarizing filter is positioned between the light source and the object such that first light emitted from the light source passes through the first polarizing filter and thereafter propagates as polarized light towards the object, and 
 the second polarizing filter is positioned over a lens of the camera such that (i) second light from the object passes through the second polarizing filter to the lens and (ii) the camera can capture a polarized image of a region of the object. 
   
     
     
         19 . The system of  claim 18  wherein the mobile device further includes the second polarizing filter. 
     
     
         20 . The system of  claim 18  wherein:
 the mobile device further includes a third polarizing filter built into the mobile device; and 
 the third polarizing filter is separate from the second polarizing filter. 
 
     
     
         21 . The system of  claim 18  wherein:
 the camera is a first camera, the lens is a first lens, and the polarized image is a first polarized image; 
 the mobile device further includes a second camera; 
 the system further includes a third polarizing filter positioned over a second lens of the second camera such that (a) third light from the object passes through the third polarizing filter to the second lens and (b) the second camera can capture a second polarized image of the region of the object; and 
 an axis of polarization of the second polarizing filter is different from an axis of polarization of the third polarizing filter.