Improved color sensor

Claim 1

In a color sensor of the type having at least one light detector for detecting light reflected or emitted by a sample containing a fluorescent agent (FA), the improvement comprising: a first source of light positioned to illuminate the sample; a second source of light positioned to illuminate the sample wherein at least a portion of the light emitted by the second source is in the excitation band of the FA; means for modulating the intensity of the second source independently of the first; and means for measuring the energy received from the object in phase synchronism with the modulation of the second source.

Claim 3

An apparatus for measuring the fluorescent properties of an object comprising: a first light source for illuminating the object: a second light source for illuminating the object wherein the second source emits a predetermined intensity of light in the excitation range of the object; means for alternately turning the second source on and off while the first source is on; means for sensing the light received from the object in a first period in which the first source is on and the second source is off and in a second period in which both the first and second sources are on. means for computing the fluorescence based on the difference in light sensed during the two periods and on the predetermined intensity of the light of the second source.

Claim 4

An apparatus for measuring the fluorescent properties of an object comprising: a first light source for illuminating the object: a second light source for illuminating the object wherein the second source emits a predetermined intensity of light in the excitation range of the object; means for alternately turning the second source on and off while the first source is on; means for sensing the light received from the object in a first period in which the first source is on and the second source is off and in a second period in which both the first and second sources are on. means for computing the fluorescence based on the difference in light sensed during the two periods and on the predetermined intensity of the light of the second source.

Claim 5

A method of measuring the effective fluorescence of an object containing a fluorescent agent (FA), comprising the steps of: illuminating the object with a first source of light; sensing the intensity of the light received from the object at one or more wavelengths while the object is illuminated by the first source to provide a first intensity measurement; illuminating the object with a second source of light while the first source also illuminates the object, said second source emitting a predetermined intensity of energy in the excitation range of the FA; sensing the intensity of the light received from the object while the object is illuminated by both sources to provide a second intensity measurement: and determining the effective fluorescence of the object from the difference in the two intensity measurements and said predetermined excitation intensity of the second source.

Claim 6

A method of measuring the effective fluorescence of an object containing a fluorescent agent (FA), comprising the steps of: illuminating the object with a first source of light; sensing the intensity of the light received from the object at one or more wavelengths while the object is illuminated by the first source to provide a first intensity measurement; illuminating the object with a second source of light while the first source also illuminates the object, said second source emitting a predetermined intensity of energy in the excitation range of the FA; sensing the intensity of the light received from the object while the object is illuminated by both sources to provide a second intensity measurement: and determining the effective fluorescence of the object from the difference in the two intensity measurements and said predetermined excitation intensity of the second source.

Claim 7

A method of determining the effective spectrum of a fluorescent object as if illuminated by a defined source, comprising the steps of: illuminating the object at a first known level of fluorescent excitation energy: sensing the intensity of the light received from the object at a plurality of wavelengths while the object is illuminated with the first level of intensity to provide a first spectrum measurement; illuminating the object with fluorescent excitation energy of a second level of intensity which is different from the first level by a known amount; sensing the intensity of the energy received from the object at said plurality of wavelengths while the object is illuminated by energy of the second level to provide a second color spectrum measurement; determining the fluorescent coefficient of the object from the difference in the two spectra measurements and the difference in the fluorescent excitation energy; determining the fluorescence suppressed spectrum of the object from the first known level of excitation energy and the determined fluorescent coefficient; and determining the correct color spectrum of the object as if it had been illuminated by a defined source from the determined fluorescent coefficient and the defined level of excitation energy of the defined source and the determined fluorescence suppressed . spectrum.

Claim 8

A method of determining the effective spectrum of a fluorescent object as if illuminated by a defined source, comprising the steps of: illuminating the object at a first known level of fluorescent excitation energy: sensing the intensity of the light received from the object at a plurality of wavelengths while the object is illuminated with the first level of intensity to provide a first spectrum measurement; illuminating the object with fluorescent excitation energy of a second level of intensity which is different from the first level by a known amount; sensing the intensity of the energy received from the object at said plurality of wavelengths while the object is illuminated by energy of the second level to provide a second color spectrum measurement; determining the fluorescent coefficient of the object from the difference in the two spectra measurements and the difference in the fluorescent excitation energy; determining the fluorescence suppressed spectrum of the object from the first known level of excitation energy and the determined fluorescent coefficient; and determining the correct color spectrum of the object as if it had been illuminated by a defined source from the determined fluorescent coefficient and the defined level of excitation energy of the defined source and the determined fluorescence suppressed . spectrum.

Claim 9

A method of measuring the fluorescent efficiency spectrum F' in an unknown sample, comprising the steps of: a) illuminating a standard sample of known fluorescent coefficient F s with a first level X s of excitation energy from a first source and detecting the level B λ of energy received from the sample at one or more wavelengths; b) illuminating the standard sample with a second source having a level X u of excitation energy and determining the intensity A λ of energy received from the sample at said one or more wavelengths; c) computing the level X u of excitation energy from the second source as follows: d) illuminating a sample of unknown fluorescence with said first level of illumination and determining the intensity B' of light received from the sample: e) illuminating the unknown sample with both said first and second sources of illumination energy and determining the level A λ of energy received from the sample: and computing the fluorescence efficiency spectrum F λ in the unknown sample as follows:

Claim 10

A method of measuring the fluorescent efficiency spectrum F' in an unknown sample, comprising the steps of: a) illuminating a standard sample of known fluorescent coefficient F s with a first level X s of excitation energy from a first source and detecting the level B λ of energy received from the sample at one or more wavelengths; b) illuminating the standard sample with a second source having a level X u of excitation energy and determining the intensity A λ of energy received from the sample at said one or more wavelengths; c) computing the level X u of excitation energy from the second source as follows: d) illuminating a sample of unknown fluorescence with said first level of illumination and determining the intensity B' of light received from the sample: e) illuminating the unknown sample with both said first and second sources of illumination energy and determining the level A λ of energy received from the sample: and computing the fluorescence efficiency spectrum F λ in the unknown sample as follows:

Claim 13

A method of computing the corrected spectrum of light energy received from a sample containing a fluorescent agent (FA) if illuminated by a defined source, comprising the steps of: a) illuminating a standard sample of known fluorescent efficiency Fs λ with a first level of illumination and detecting the spectrum B of light energy received from the sample at a plurality of wavelengths λ; b) illuminating the standard sample with a second level of energy and determining the spectrum A λ of light received from the sample at said plurality of wavelengths; c) computing the level X u of increased excitation energy between the two levels as follows: d) computing the level X s of excitation energy of said first level of illumination as follows: where the suppressed fluorescent spectrum C of the standard sample is known; and e) illuminating a sample of unknown fluorescence with said first level of energy and determining the spectrum B' λ of light energy received from the sample at said plurality of wavelengths; f) illuminating the unknown sample with said second level of energy and determining the color spectrum A' λ of light received from the sample at said plurality of wavelengths; g) computing the fluorescent efficiency F' λ in the unknown sample as follows: h) computing the fluorescent suppressed color spectrum Ci of the unknown sample as follows: i) computing the correct spectrum D' λ of the unknown sample as if it had been illuminated by a defined source as follows: where the level X D of excitation energy of the defined source is known.

Claim 14

A method of computing the corrected spectrum of light energy received from a sample containing a fluorescent agent (FA) if illuminated by a defined source, comprising the steps of: a) illuminating a standard sample of known fluorescent efficiency Fs λ with a first level of illumination and detecting the spectrum B of light energy received from the sample at a plurality of wavelengths λ; b) illuminating the standard sample with a second level of energy and determining the spectrum A λ of light received from the sample at said plurality of wavelengths; c) computing the level X u of increased excitation energy between the two levels as follows: d) computing the level X s of excitation energy of said first level of illumination as follows: where the suppressed fluorescent spectrum C of the standard sample is known; and e) illuminating a sample of unknown fluorescence with said first level of energy and determining the spectrum B' λ of light energy received from the sample at said plurality of wavelengths; f) illuminating the unknown sample with said second level of energy and determining the color spectrum A' λ of light received from the sample at said plurality of wavelengths; g) computing the fluorescent efficiency F' λ in the unknown sample as follows: h) computing the fluorescent suppressed color spectrum Ci of the unknown sample as follows: i) computing the correct spectrum D' λ of the unknown sample as if it had been illuminated by a defined source as follows: where the level X D of excitation energy of the defined source is known.