Device for optical imaging of features of a hand

Abstract

The present disclosure relates to a device for contactless optical imaging of features of a hand, wherein the device comprises an illumination arrangement for illuminating a measuring site with light of substantially a first wavelength and with light of at least substantially a second wavelength. The device further comprising a camera comprising a detector and imaging optics configured for imaging the measuring site on the detector. Within the measuring site a region of depth of field of the imaging optics with respect to the first wavelength overlaps with a region of depth of field of the imaging optics with respect to the second wavelength.

1 . A device for contactless optical imaging of features of a hand, wherein the device comprises:
 an illumination arrangement for illuminating a measuring site by emitting light of a substantially first wavelength and by emitting light of a substantially second wavelength;   a first camera comprising a first detector and first imaging optics configured for imaging the measuring site on the first detector, which is configured for acquiring that image, within the measuring site a region of depth of field of the first imaging optics with respect to the first wavelength overlapping with a region of depth of field of the first imaging optics with respect to the second wavelength;   at least a second camera comprising a second detector and second imaging optics configured for imaging the measuring site on the second detector, which is configured for acquiring that image, within the measuring site a region of depth of field of the second imaging optics with respect to the first wavelength overlapping with a region of depth of field of second imaging optics with respect to the second wavelength; and   an image editing module configured for generating a three-dimensional image of a surface of an object within the measuring site by combining the image acquired by the first detector together with the image acquired by the second detector.   
     
     
         2 . The device of  claim 1 , wherein the device does not comprise a contact window having a contact surface within the measuring site. 
     
     
         3 . The device of  claim 2 , wherein the first wavelength is not less than 400 nm. 
     
     
         4 . The device of  claim 3 , wherein the second wavelength is not less than 450 nm. 
     
     
         5 . The device of  claim 4 , wherein first camera and the second camera are arranged in a Scheimpflug layout. 
     
     
         6 . The device of  claim 1 , wherein first camera and the second camera are arranged in a Scheimpflug layout. 
     
     
         7 . The device of  claim 1 , wherein the first detector and the second detector are arranged so as to be tilted, with respect to a plane in the measuring site such that they meet the Scheimpflug conditions. 
     
     
         8 . The device of  claim 1 , wherein the first detector and the second detector are arranged so as to be tilted, with respect to a measuring plane such that they meet the Scheimpflug conditions. 
     
     
         9 . The device of  claim 1 , wherein the measuring site comprises a region of depth of field of the first imaging optics at a third wavelength which overlaps with the region of depth of field of the first imaging optics at the first wavelength. 
     
     
         10 . The device of  claim 9 , wherein the measuring site comprises a region of depth of field of the second imaging optics at a third wavelength which overlaps with the region of depth of field of the second imaging optics at the first wavelength. 
     
     
         11 . The device of  claim 2 , wherein the measuring site comprises a region of depth of field of the first imaging optics at a third wavelength which overlaps with the region of depth of field of the first imaging optics at the first wavelength, and wherein the measuring site comprises a region of depth of field of the second imaging optics at the third wavelength which overlaps with the region of depth of field of the second imaging optics at the first wavelength. 
     
     
         12 . The device of  claim 1 , wherein the distance between the first imaging optics and the measuring site is at least 150 mm. 
     
     
         13 . The device of  claim 12 , wherein the distance between the second imaging optics and the measuring site is at least 150 mm. 
     
     
         14 . A device for contactless optical imaging of features of a hand, wherein the device comprises:
 an illumination arrangement for illuminating a measuring site, the illumination arrangement comprising a first lamp for emitting light of substantially a first wavelength, and at least a second lamp for emitting light of substantially a second wavelength; and   a camera comprising a detector and imaging optics configured for imaging the measuring site on the detector, which is configured for acquiring that image; wherein within the measuring site a region of depth of field of the first imaging optics with respect to the first wavelength overlaps with a region of depth of field of the first imaging optics with respect to the second wavelength.   
     
     
         15 . The device of  claim 14 , wherein the device does not comprise a contact window having a contact surface within the measuring site. 
     
     
         16 . The device of  claim 15 , wherein the first wavelength is not less than 400 nm. 
     
     
         17 . The device of  claim 16 , wherein the second wavelength is not less than 450 nm. 
     
     
         18 . The device of  claim 15 , wherein the measuring site comprises a region of depth of field of the imaging optics at a third wavelength which overlaps with the region of depth of field of the imaging optics at the first wavelength. 
     
     
         19 . The device of  claim 18 , wherein the distance between the imaging optics and the measuring site is at least 150 mm. 
     
     
         20 . A device for contactless optical imaging of features of a hand, wherein the device comprises:
 an illumination arrangement for illuminating a measuring site by emitting light of a wavelength substantially corresponding to a first wavelength and by emitting light of a wavelength substantially corresponding to a second wavelength, the first wavelength being no less than 400 nm, the first wavelength being no greater than 650 nm, the second wavelength being no less than 450 nm, and the second wavelength being no greater than 670 nm;   a first camera comprising a first detector and first imaging optics configured for imaging the measuring site on the first detector, which is configured for acquiring that image, within the measuring site a region of depth of field of the first imaging optics with respect to the first wavelength overlapping with a region of depth of field of the first imaging optics with respect to the second wavelength;   at least a second camera comprising a second detector and second imaging optics configured for imaging the measuring site on the second detector, which is configured for acquiring that image, within the measuring site a region of depth of field of the second imaging optics with respect to the first wavelength overlapping with a region of depth of field of the second imaging optics with respect to the second wavelength; and   an image editing module configured for generating a three-dimensional image of a surface of an object within the measuring site by processing the image acquired by the first detector together with the image acquired by the second detector.   
     
     
         21 . The device of  claim 20 , wherein the device does not comprise a contact window having a contact surface within the measuring site. 
     
     
         22 . The device of  claim 21 , wherein first camera and the second camera are arranged in a Scheimpflug layout. 
     
     
         23 . The device of  claim 22 , wherein the measuring site comprises a region of depth of field of the first imaging optics at a third wavelength which overlaps with the region of depth of field of the first imaging optics at the first wavelength, and wherein the measuring site comprises a region of depth of field of the first imaging optics at a third wavelength which overlaps with the region of depth of field of the first imaging optics at the first wavelength. 
     
     
         24 . The device of  claim 23 , wherein the length of optical path between the first imaging optics and the measuring site is at least 150 mm, and wherein the length of optical path between the second imaging optics and the measuring site is at least 150 mm.