Apparatus for caries detection
View Patent ↗An apparatus for obtaining an image of a tooth having at least one light source providing incident light having a first spectral range for obtaining a reflectance image from the tooth and a second spectral range for exciting a fluorescence image from the tooth. A polarizing beamsplitter in the path of the incident light from both sources directs light having a first polarization state toward the tooth and directs light from the tooth having a second polarization state along a return path toward a sensor, wherein the second polarization state is orthogonal to the first polarization state. A first lens in the return path directs image-bearing light from the tooth toward the sensor, and obtains image data from the portion of the light having the second polarization state. A long-pass filter in the return path attenuates light in the second spectral range.
1. An apparatus for imaging a tooth comprising:
at least one light source for providing an incident light having a first spectral range for obtaining a reflectance image on the tooth and a second spectral range for exciting a fluorescence image of the tooth;
a polarizer in the path of the incident light and disposed to direct light having a first polarization state toward the tooth;
an analyzer disposed to direct light obtained from the tooth and having a second polarization state along a return path toward a sensor,
wherein the second polarization state is substantially orthogonal to the first polarization state;
a lens positioned in the return path to direct image-bearing light from the tooth toward the sensor for obtaining image data from the portion of the light having the second polarization state; and
a long-pass filter in the return path, to attenuate light in the second spectral range and to transmit light in the first spectral range.
2. The apparatus according to claim 1 further comprising:
a display mounted on the body of the apparatus and in communication with the sensor for displaying the image of the tooth.
3. The apparatus as in claim 1 further comprising:
an interferometer coupled along the optical path for obtaining an image of a portion of the tooth using optical coherence tomography.
4. An apparatus for imaging a tooth comprising:
a handle portion for handling and positioning by an operator;
a probe portion, separable from the handle portion, for placement in the proximity of the tooth; and
an optical subsystem housed within the handle and probe portions comprising:
(i) at least one light source providing incident light having a first spectral range for obtaining a reflectance image on the tooth and a second spectral range for exciting a fluorescence image of the tooth;
(ii) a polarizer in the path of the incident light and disposed to direct light having a first polarization state toward the tooth;
(iii) an analyzer disposed to direct light obtained from the tooth and having a second polarization state along a return path toward a sensor, wherein the second polarization state is substantially orthogonal to the first polarization state;
(iv) a lens positioned in the return path to direct image-bearing light from the tooth toward the sensor for obtaining image data from the portion of the light having the second polarization state; and
(v) a long-pass filter in the return path, to attenuate light in the second spectral range and to transmit light in the first spectral range.