Virus identification apparatus and method

Claim 1

An apparatus for the identification of viruses in static fluid suspension which comprises in combination: a. means for generating collimated, high intensity, substantially monochromatic radiation having a chosen wavelength; b. a first polarizer for receiving and substantially linearly polarizing said substantially monochromatic radiation, said polarized radiation being emitted from said first polarizer having a polarization directed along a first axis; c. a first modulator having a first retardance of between 1/4-wavelength and 1/2-wavelength of said emitted polarized radiation for receiving said linearly polarized radiation and generating polarization modulated elliptically polarized radiation therefrom, said modulation having a first frequency; d. means for receiving the virus sample to be identified, for permitting said modulated elliptically polarized radiation to enter and interact therewith, and for permitting the radiation scattered thereby to emerge; e. a second modulator having a second retardance of between 1/4-wavelength and 1/2-wavelength of said emitted polarized radiation for receiving a portion of said emerging scattered radiation at a chosen angle and generating polarization modulated radiation therefrom which has a second modulation frequency simultaneously impressed thereon; f. a second polarizer for receiving said scattered radiation bearing two polarization modulation frequencies and interacting therewith to pass a component of said scattered radiation having its polarization directed along a second axis, said first retardance and said second retardance, and said first axis and said second axis being chosen such that the dc component of the intensity of said scattered radiation is independent of polarization in order that a normalization of said scattered radiation can be achieved; g. means for quantitatively detecting said radiation passed by said second polarizer, said quantitative detection means having sensitivity to each individual frequency of a plurality of frequencies present in said 'radiation passed by said second polarizer, said individual frequencies resulting from the effect of said first polarization modulator and said second polarization modulator on said emitted polarized radiation -and said scattered radiation, respectively: and h. means for identifying and measuring the intensity associated with each individual frequency of said plurality of frequencies present in said quantitatively detected radiation passed by said second polarizer, each of said intensities thereby identified and measured having a definite mathematical relationship substantially to a particular Mueller matrix element, said Mueller matrix elements deriving from the interaction of said virus sample with said polarization modulated elliptically polarized radiation: whereby eight matrix elements can be extracted. said matrix elements, when normalized by said intensity of said scattered radiation, containing information according to the nature of the virus under investigation.

Claim 2

An apparatus for the identification of viruses in static fluid suspension which comprises in combination: a. means for generating collimated, high intensity, substantially monochromatic radiation having a chosen wavelength; b. a first polarizer for receiving and substantially linearly polarizing said substantially monochromatic radiation, said polarized radiation being emitted from said first polarizer having a polarization directed along a first axis; c. a first modulator having a first retardance of between 1/4-wavelength and 1/2-wavelength of said emitted polarized radiation for receiving said linearly polarized radiation and generating polarization modulated elliptically polarized radiation therefrom, said modulation having a first frequency; d. means for receiving the virus sample to be identified, for permitting said modulated elliptically polarized radiation to enter and interact therewith, and for permitting the radiation scattered thereby to emerge; e. a second modulator having a second retardance of between 1/4-wavelength and 1/2-wavelength of said emitted polarized radiation for receiving a portion of said emerging scattered radiation at a chosen angle and generating polarization modulated radiation therefrom which has a second modulation frequency simultaneously impressed thereon; f. a second polarizer for receiving said scattered radiation bearing two polarization modulation frequencies and interacting therewith to pass a component of said scattered radiation having its polarization directed along a second axis, said first retardance and said second retardance, and said first axis and said second axis being chosen such that the dc component of the intensity of said scattered radiation is independent of polarization in order that a normalization of said scattered radiation can be achieved; g. means for quantitatively detecting said radiation passed by said second polarizer, said quantitative detection means having sensitivity to each individual frequency of a plurality of frequencies present in said 'radiation passed by said second polarizer, said individual frequencies resulting from the effect of said first polarization modulator and said second polarization modulator on said emitted polarized radiation -and said scattered radiation, respectively: and h. means for identifying and measuring the intensity associated with each individual frequency of said plurality of frequencies present in said quantitatively detected radiation passed by said second polarizer, each of said intensities thereby identified and measured having a definite mathematical relationship substantially to a particular Mueller matrix element, said Mueller matrix elements deriving from the interaction of said virus sample with said polarization modulated elliptically polarized radiation: whereby eight matrix elements can be extracted. said matrix elements, when normalized by said intensity of said scattered radiation, containing information according to the nature of the virus under investigation.

Claim 4

The apparatus as described in Claims 1 or 2, wherein said first modulator and said second modulator include photoelastic modulators, said photoelastic modulators having sinusoidally varying retardance amplitudes at said first frequency and said second frequency, respectively.

Claim 10

The apparatus as described in Claims 6 or 7, wherein a first polarizer is inserted between said laser and said first modulator for receiving and polarizing said substantially monochromatic laser radiation, said polarized radiation being emitted, from said second polarizer having a polarization directed along a third axis; whereby said first retardance and said second retardance, and said second axis and said third axis are chosen such that the dc component of the intensity of said scattered radiation is independent of polarization in order that a normalization of said scattered radiation is independent of polarization in order that a normalization of said scattered radiation can be achieved.

Claim 14

A method for the characterization and identification of virus samples in static suspension, said method comprising the steps of: a. generating substantially monochromatic electromagnetic radiation having a chosen wavelength; b. linearly polarizing said generated monochromatic radiation along a first axis; c. generating a first modulated elliptically polarized radiation from said polarized monochromatic radiation, said first modulated elliptically polarized radiation being a superposition of waves having a phase lag of between 1/4-wavelength and 1/2-wavelength of said substantially monochromatic radiation, and having a first modulation frequency; d. directing said first modulated elliptically polarized radiatioi through the static virus suspension to be analyzed; e. allowing said first modulated elliptically polarized radiation to interact with the static virus suspension, thereby producing scattered radiation containing polarization information related to the suspended virus; f. generating a second modulated elliptically polarized radiation from a portion of said scattered radiation emitted from the static virus suspension at a chosen scattering angle, said second modulated elliptically polarized radiation being a superposition of · waves having a phase lag of between 1/4-wavelength and 1/2-wavelength of said substantially monochromatic radiation, and having a second modulation frequency; g. extracting a linearly polarized component from said second modulated elliptically polarized radiation along a second axis: h. detecting the intensity of said linearly polarized component along said second axis, said intensity bearing amplitude modulation at certain frequencies which are linear combinations of said first modulation frequency and said second modulation frequency: and i. extracting the magnitude of said intensity at said certain frequencies, whereby eight Mueller matrix elements are measured substantially independent of each other, said M ueller matrix elements bearing information according to the nature of the virus suspension under investigation.

Claim 15

A method for the characterization and identification of virus samples in static suspension, said method comprising the steps of: a. generating substantially monochromatic electromagnetic radiation having a chosen wavelength; b. linearly polarizing said generated monochromatic radiation along a first axis; c. generating a first modulated elliptically polarized radiation from said polarized monochromatic radiation, said first modulated elliptically polarized radiation being a superposition of waves having a phase lag of between 1/4-wavelength and 1/2-wavelength of said substantially monochromatic radiation, and having a first modulation frequency; d. directing said first modulated elliptically polarized radiatioi through the static virus suspension to be analyzed; e. allowing said first modulated elliptically polarized radiation to interact with the static virus suspension, thereby producing scattered radiation containing polarization information related to the suspended virus; f. generating a second modulated elliptically polarized radiation from a portion of said scattered radiation emitted from the static virus suspension at a chosen scattering angle, said second modulated elliptically polarized radiation being a superposition of · waves having a phase lag of between 1/4-wavelength and 1/2-wavelength of said substantially monochromatic radiation, and having a second modulation frequency; g. extracting a linearly polarized component from said second modulated elliptically polarized radiation along a second axis: h. detecting the intensity of said linearly polarized component along said second axis, said intensity bearing amplitude modulation at certain frequencies which are linear combinations of said first modulation frequency and said second modulation frequency: and i. extracting the magnitude of said intensity at said certain frequencies, whereby eight Mueller matrix elements are measured substantially independent of each other, said M ueller matrix elements bearing information according to the nature of the virus suspension under investigation.

Claim 17

The method as described in claims 12 or 13, wherein said steps a. to i. are repeated for a plurality of wavelengths.