Apparatus for caries detection

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.

An apparatus for imaging a tooth comprising:

• at least one light source for providing, along an optical path, an incident light to illuminate the tooth;
• a spectral separator in the optical path to direct light of a first spectral band that is reflected from the tooth toward a first sensor and other light from the tooth toward a second sensor;
• and
• a lens positioned in the optical path to form an image of the tooth, through the spectral separator, onto the first and second sensors for obtaining image data from the tooth.

A method for imaging a tooth comprising:

• providing incident light having a first spectral range for obtaining a reflectance image from the tooth;
• providing incident light having a second spectral range for exciting a fluorescence image from the tooth;
• directing light having a first polarization state toward the tooth and directing 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;
• directing 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
• attenuating light in the second spectral range and transmitting light in the first spectral range.