Acousto-optic tunable filter-based surface scanning system and process

A system for scanning a rough surface to obtain near real-time data concerning characteristics of the surface, comprising:

• a light source capable of generating an incident beam of light;
• an optical interface configured to receive the incident beam of light from the light source and direct the incident beam onto a discrete location on the surface, the optical interface further configured to gather at least a portion of the beam which is scattered off the surface;
• an acousto-optic tunable filter positioned to receive the incident beam, the filter tuned to pass light corresponding to the absorption band of a predetermined material and at least one reference band outside the absorption band, the acousto-optic tunable filter being inherently configured to linearly polarize the incident beam to produce two orthogonal components of polarized light exiting the filter at different angles, the optical interface further including a partition positioned to block one of the components of polarized light from being directed onto the surface;
• an analyzing polarizer positioned to receive the gathered portion of the scattered beam;
• a detector positioned to receive the gathered portion of the scattered beam from the analyzing polarizer, the detector capable of monitoring the intensity of light at the absorption band of the predetermined material and at the reference band, the detector capable of generating a signal corresponding to the intensity of each wavelength being monitored;
• a signal processor in communication with the detector for processing the signal generated by the detector;
• and
• means for moving the optical interface relative to the surface such that the surface may be scanned with the beam of light.

A system for scanning a surface to obtain near real-time data concerning characteristics of the surface, comprising:

• a light source capable of generating an incident beam of light including wavelengths in the ultraviolet range;
• an optical interface configured to receive the incident beam of light from the light source and direct the incident beam onto a discrete location on the surface, the optical interface further configured to gather at least a portion of the fluorescent beam emitted from the surface;
• a polarizer positioned to polarize the incident beam of light;
• an acousto-optic tunable filter positioned to receive the gathered portion of the fluorescent beam, the filter tuned to pass light corresponding to the fluorescent wavelength of a predetermined material;
• a detector positioned to receive the fluorescent beam emitted from the surface, the detector capable of monitoring the intensity of light at the fluorescent wavelength of the predetermined material, the detector capable of generating a signal corresponding to the intensity of the wavelength being monitored;
• a signal processor in communication with the detector for processing the signal generated by the detector;
• and
• means for moving the optical interface relative to the surface such that the surface may be scanned with the beam of light.

A process for scanning a rough surface to obtain near real-time data concerning characteristics of the surface, comprising the steps of:

• generating an incident beam of light with a light source;
• passing the incident beam of light through an acousto-optic tunable filter tuned to pass light corresponding to the absorption band of a predetermined material and at least one reference band outside the absorption band;
• polarizing the incident beam;
• directing the incident beam of light passed through the acousto-optic tunable filter onto a discrete location on the surface;
• gathering at least a portion of the beam scattered off the surface;
• directing the gathered portion of the scattered beam through an analyzing polarizer;
• introducing the gathered portion of the scattered beam into a detector capable of monitoring the intensity of light at the absorption band of the predetermined material and at the reference band, the detector capable of generating a signal corresponding to the intensity of each wavelength being monitored;
• analyzing the intensity of the gathered portion of the scattered beam at the absorption band of the predetermined material and at the reference band;
• and
• selecting a different discrete location on the surface and repeating the preceding steps.

A process for scanning a surface to obtain near real-time data concerning characteristics of the surface, comprising the steps of:

• generating an incident beam of light including wavelengths in the ultraviolet range;
• passing the incident beam through a polarizer to polarize the incident beam of light;
• directing the incident beam onto a discrete location on the surface;
• gathering at least a portion of the fluorescent beam emitted from the surface;
• passing the gathered portion of the fluorescent beam through an analyzing polarizer;
• passing the gathered portion of the fluorescent beam through an acousto-optic tunable filter tuned to pass light corresponding to the fluorescent wavelength of a predetermined material;
• introducing the light passed through the acousto-optic tunable filter into a detector capable of monitoring the intensity of light at the fluorescent wavelength of the predetermined material, the detector capable of generating a signal corresponding to the intensity of the wavelength being monitored;
• analyzing the intensity of the gathered light at the fluorescent wavelength of the predetermined material;
• and
• selecting a different discrete location on the surface and repeating the preceding steps.