Method for measuring internal information in scattering medium and apparatus for the same

Claim 1

A method of measuring a scattering medium comprising: emitting light having a single predetermined wavelength; causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points being different from each other, to obtain at least three detected signals; and extracting internal information of the scattering medium with respect to said wavelength of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU7## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU8## a is a constant determined in accordance with a type of the scattering medium, μ a represents an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 2

A method of measuring a scattering medium comprising: emitting light having a single predetermined wavelength; causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points being different from each other, to obtain at least three detected signals; and extracting internal information of the scattering medium with respect to said wavelength of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU7## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU8## a is a constant determined in accordance with a type of the scattering medium, μ a represents an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 6

A method of measuring a scattering medium comprising: emitting light having at least two predetermined wavelengths of which absorption coefficients to specified absorptive constituents in said scattering medium differ from one another; causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points differing from one another, to obtain at least three detected signals with respect to each of said wavelengths of said light; and extracting internal information of the scattering medium with respect to each of said wavelengths of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU9## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU10## a is a constant determined in accordance with a type of the scattering medium, μ a is an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 7

A method of measuring a scattering medium comprising: emitting light having at least two predetermined wavelengths of which absorption coefficients to specified absorptive constituents in said scattering medium differ from one another; causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points differing from one another, to obtain at least three detected signals with respect to each of said wavelengths of said light; and extracting internal information of the scattering medium with respect to each of said wavelengths of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU9## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU10## a is a constant determined in accordance with a type of the scattering medium, μ a is an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 14

An apparatus for measuring a scattering medium comprising: light-emitting means for emitting light having a single predetermined wavelength; light-incident means for causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; photodetecting means for detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points differing from one another, to obtain at least three detected signals; and arithmetic processing means for extracting internal information of the scattering medium with respect to said wavelength of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said three or more measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU11## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU12## a is a constant determined in accordance with a type of the scattering medium, μ a is an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 15

An apparatus for measuring a scattering medium comprising: light-emitting means for emitting light having a single predetermined wavelength; light-incident means for causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; photodetecting means for detecting said light which has propagated through the scattering medium at at least three photodetection points, with distances, ρ i , between the light incidence position and each of the photodetection points differing from one another, to obtain at least three detected signals; and arithmetic processing means for extracting internal information of the scattering medium with respect to said wavelength of said light, by converting said at least three detected signals to at least three measured values, Q(ρ i ), and then performing arithmetic processing to said three or more measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU11## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η is a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU12## a is a constant determined in accordance with a type of the scattering medium, μ a is an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 19

An apparatus for measuring a scattering medium comprising: light-emitting means for emitting light having at least two predetermined wavelengths of which absorption coefficients to a specified absorptive constituent in said scattering medium differ from one another; light-emitting means for causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; photodetecting means for detecting said light which has been propagated through the scattering medium at at least three photodetection points, with distances, μ i , between the light incidence position and each of the photodetection points being different from each other, to obtain at least three detected signals with respect to each of said wavelengths of said light; and first arithmetic processing means for extracting internal information of the scattering medium with respect to each of said wavelengths of said light, by converting said at least three detected signals to at least three measured values, Q(P i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU13## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η represents a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU14## a is a constant determined in accordance with a type of the scattering medium, μ a designates an absorption coefficient, and μ s ' is a transport scattering coefficient.

Claim 20

An apparatus for measuring a scattering medium comprising: light-emitting means for emitting light having at least two predetermined wavelengths of which absorption coefficients to a specified absorptive constituent in said scattering medium differ from one another; light-emitting means for causing said light to be incident on the scattering medium at a light incidence position to allow said light to propagate through the scattering medium; photodetecting means for detecting said light which has been propagated through the scattering medium at at least three photodetection points, with distances, μ i , between the light incidence position and each of the photodetection points being different from each other, to obtain at least three detected signals with respect to each of said wavelengths of said light; and first arithmetic processing means for extracting internal information of the scattering medium with respect to each of said wavelengths of said light, by converting said at least three detected signals to at least three measured values, Q(P i ), and then performing arithmetic processing to said at least three measured values, Q(ρ i ), based on a simultaneous relation of the following equation: ##EQU13## for z 0 =a/(μ a +μ s ') where i is an integer running from one to at least three, η represents a light attenuation factor, μ eff is an effective attenuation coefficient ##EQU14## a is a constant determined in accordance with a type of the scattering medium, μ a designates an absorption coefficient, and μ s ' is a transport scattering coefficient.